Geomatica Focus. User Guide. Version 10.1

Transcription

1 User Guide Version 10.1

2 2007 Enterprises Inc.. All rights reserved. COPYRIGHT NOTICE Software copyrighted by, 50 West Wilmot St., Suite 200, Richmond Hill, ON CANADA L4B 1M5 Telephone number: (905) RESTRICTED RIGHTS Canadian Government Use, duplication, or disclosure by the Government is subject to restrictions as set forth in DSS "General Conditions - Short Form - Licensed Software". U.S. Government Use, duplication, or disclosure by the Government is subject to restrictions set forth in subparagraph (b)(3) of the Rights in Technical Data and Computer Software clause of DFARS or subparagraph (c)(1) and (2) of the Commercial Computer Software-Restricted Rights clause at 48 CFR as amended, or any successor regulations thereto. PCI,, PCI and design (logo), Geomatica, Committed to GeoIntelligence Solutions, GeoGateway, FLY!, OrthoEngine, RADARSOFT, EASI/PACE, ImageWorks, GCPWorks, PCI Author, PCI Visual Modeler, and SPANS are registered trademarks of PCI Geomatics Enterprises, Inc. Sentinel is a registered trademark of SafeNet, Inc. All other trademarks and registered trademarks are the property of their respective owners.

3 Table of Contents Using the Focus online help Using technical references Using the GDB formats reference Working with Focus Opening a file Adding data to a project Using the Add Layer wizard Understanding the Focus control pane Using the Maps and Files trees Changing the layer priority Viewing layer properties Viewing auxiliary data Adding image channels Combining layers...30 About the Combined Layer dialog box About the Select Layer dialog box Working with project files Saving a project Using the Layer Manager Changing layer properties Using the Zoom Scale Active feature About rotated rasters...34 Managing data properties About the Map Properties dialog box General tab Page Setup tab Default RST tab About the Area Properties dialog box...37 General tab Layout tab...38 Projection/Extents tab Using a math model with images Using the math model for georeferencing...41 i

4 About the Math Model Area Properties dialog box...42 General tab Layout tab Projection/Extents tab About the RGB Layer Properties dialog box General tab Source Images tab Source LUTs tab Display tab Display within Zoom Scale tab About the Grayscale Layer Properties dialog box General tab Source Images tab Source LUTs tab Display tab Display within Zoom Scale tab Labels tab About the PCT Layer Properties dialog box...50 General tab Source Image tab Display tab Display within Zoom Scale tab Labels tab About the Bitmap Layer Properties dialog box...52 General tab Source Images tab Display tab Display within Zoom Scale tab About the Vector Layer Properties dialog box...53 General tab Display within Zoom Scale tab Labels tab About the Thematic Layer Properties dialog box General tab Display tab Display within Zoom Scale tab Labels tab About the RST Properties dialog box About the Modify dialog box About the Symbol Properties dialog box...56 Using the File Properties dialog box...57 ii

5 About the Bitmap Properties dialog box General tab History tab MetaData tab About the File Properties dialog box General tab History tab MetaData tab Projection tab About the Ground Control Points dialog box...61 General tab History tab MetaData tab About the Look-up Table Properties dialog box General tab History tab MetaData tab About the Orbit Properties dialog box General tab History tab MetaData tab About the Pseudo-color table properties General tab History tab MetaData tab About the Raster Properties dialog box General tab History tab MetaData tab About the Signatures Properties dialog box General tab History tab MetaData tab About the Text Properties dialog box General tab History tab MetaData tab About the Vector Properties dialog box General tab History tab MetaData tab iii

6 Projection tab About the Other Projections dialog box Color mapping and image profiles About the RGB Mapping dialog box Creating an image profile About the Profile Table dialog box About the Profile Options dialog box About the Profile Graph dialog box About the Graph Controls dialog box Using the graph controls Exporting profiles Printing your graph without showing the mensuration bars Using the View tools Using the Zoom window Using a Clone view Chaining clone views Zooming using the Overview window Creating named regions Removing named regions Creating named regions using coordinates Panning an image Zooming an image with zoom tools Viewing a 1:1 image resolution Using a layout grid...81 Grid spacing Index spacing Visualizing your data Enhancing images Using the Attribute Manager Importing XML metadata using the METAIN algorithm Opening an image data set Viewing global metadata Viewing band-specific metadata...85 Enabling and disabling panes Changing the units for the cursor position Using the Visualization tools About the Visualization Tools dialog box...86 Using the Flicker tool Using the Swipe tool Using the Blend tool Using the Loop tool iv

7 Using the Cycle tool Using the Band Cycling tool Opening the Thumbnails viewer...92 About the Thumbnails viewer Using the Thumbnails viewer Selecting grayscale and RGB layers...95 Visualizing data with the 3-D data cube...95 About the 3-D data cube controls About the Select PCT Layer dialog box Selecting colors Color palettes Color models Setting options and preferences General interface Warnings Layers Default representation Vector editing Memory cache Optimizing the Undo/Redo options Optimizing the tiling cache Setting the total cache limit Setting the vector read cache Overview window Zoom window Layer Manager Open GL settings Setting shape and color preferences Modifying a selected line Modifying a selected polygon Applying preferences to selected text Changing the style for hatches Changing the raster color Changing the raster size Setting up a digitizing tablet using Wintab Setting up a digitizing tablet using a driver Testing the digitizing tablet connection Assigning text actions and modifiers Setting up a GPS receiver Testing the GPS connection Measurement tools v

8 Changing display options About the Display Options dialog box Customizing the Focus toolbars About the Toolbar Configuration dialog box Supported layer types Focus and raster layers Metadata Segment organization Topological layers Arc layers Node layers: Area layers Representation Style Tables (RST) Importing, linking, and translating data Importing files to the PCIDSK format Building raster overviews Deleting raster overviews Linking PCIDSK and other databases Translating file formats Importing and converting ASCII files Using the Import ASCII Table/Points wizard Formating fixed width files Opening data from a remote data source Using undefined image data Image metadata support Working with projections Understanding PCIDSK projection definition Supported projections Defining a new projection Defining datums and ellipsoids Reprojecting files About the Reproject dialog box Reprojection bounds Selectable layers and reprojection Setting reprojection bounds Specifying a coordinate system Selecting an ellipsoidal earth model Selecting the earth model Selecting the SPCS coordinate system Selecting a different coordinate system Maximum bounds and resampling methods vi

9 Selecting database layers for reprojection Organizing and editing layers Adding and removing imagery Creating a new raster layer Creating a new bitmap layer Creating a new vector layer Setting vector layer attributes Setting vector layer properties Transferring layers Working with data tools Changing data formats About the Bitmap Save As dialog box About the Vector Save As dialog box Selecting GDB format options About the Grayscale Save As dialog box About the Output Layer Properties dialog box About the PCT Output Layer Properties dialog box About the RST Save As dialog box About the RGB Save As dialog box About the PCT Save As dialog box About the LUT Save As dialog box Opening the Clipping/Subsetting panel Clipping and subsetting images Defining the clip region with user-entered coordinates Defining the clip region by selecting a file Defining the clip region by selecting a layer Defining the clip region by selecting a named region Defining the clip region by selecting a script subset file Creating the text file for the Script Subset File method Defining the clip region using the Zoom tools Creating multiple subset tiles Selecting a clip region Opening the Data Merge wizard Choosing an input layer Naming the output file Setting up output layers Data Merge wizard - Set Bitmap Parameters dialog box Data Merge wizard - Set Image Parameters dialog box Opening the Algorithm Librarian About the Algorithm Librarian dialog box Algorithm licensing vii

10 Algorithm categories Algorithm sub-categories Finding an algorithm Using the Find Algorithm utility Searching for an algorithm by category Creating user-defined categories Adding algorithms to the user defined folder Using an algorithm About module control panels Finding help topics for all algorithms Finding help from the Algorithm Librarian dialog box Finding help from a Module Control Panel Working with an algorithm MCP Working with an example Using the ASP algorithm Setting up the input port Setting up output ports Setting up input parameters Running the ASP algorithm Viewing the results Understanding the results Adding functions to the algorithm library Starting a classification session Unsupervised classification Configuring a new classification session Initializing unsupervised classification Reading a classification report Supervised classification The supervised classification process Initializing a supervised classification Specifying the reference image Specifying the input channels Training sites and ground cover Drawing a class training site Making corrections About the Erase Settings dialog box Changing training site colors Importing training sites Importing vectors Opening the Import Bitmaps dialog box About the Import Bitmaps dialog box viii

11 Importing a specified bitmap as its training site Importing signatures from the training site editor Filling polygons using the Raster Seeding function About the Raster Seeding dialog box Filling a polygon Merging classes Analyzing training sites Testing signature separability Testing separability with a scatter plot Creating a scatter plot Adjusting scatter plot threshold values Altering the view range for the X and Y axes Exporting the scatter plot file Displaying the color scale legend Printing the scatter plot Previewing the classification Setting the Maximum Likelihood classification preview Removing the preview classification from the metalayer Creating a separability report Saving the separability report to an existing file Running a supervised classification Testing accuracy with signature statistics Viewing signature statistics Viewing a matrix report Comparing signature statistics Saving the signature statistics report Post-classification editing Improving classification results Initialize post-classification editing Setting up a bitmap mask Opening a bitmap mask Saving a bitmap mask Masking an image area Opening an aggregation session Opening the Aggregate dialog box in an unsupervised session Setting up an aggregation Setting up a new aggregate class Creating an aggregate from a set of input classes Changing the input and output channel assignments Assigning a new PCT to the current session Generating a PCT ix

12 Importing a PCT Saving the aggregate session Starting an aggregate session Importing other classes Setting up for class labelling About the Class Labelling dialog box Initializing classes from a classification channel Initializing classes from a text file Launching the Accuracy Assessment dialog box Using the Accuracy Assessment dialog box Selecting a classified image Selecting a reference image Generating a random sample Assigning a reference class to a sample Opening samples from a vector segment Launching the Accuracy Report dialog box Producing a random sample report Producing an error report Producing an accuracy statistics report Saving an accuracy report Information tools Opening the Information report Viewing information for a selected vector Viewing information for vectors under the cursor Showing information for raster data Displaying the attributes from a chart Specifying the units of measurement Selecting a Measure tool Measuring a line Measuring a polygon Measuring a rectangle or ellipse Reading the Measure tool report Viewing histograms and statistics Viewing a histogram Viewing histogram statistics Viewing Mask contents Viewing histograms under a bitmap mask Zooming into and out of a histogram Printing a histogram Exporting a histogram Working with numeric values x

13 Opening the Numeric Values dialog box Exporting the numeric values to a text file Change a color channel DN value Interpreting the values Making an image profile Using the mensuration bars Selecting vector profiles Using the spectra extraction tools Extracting spectra from a region of interest About the Spectra Extraction Configuration dialog box Configuring a hyperspectral metalayer About the Spectra Extraction dialog box Region menu Edit menu Tools menu Spectra extraction table About the Import Vectors dialog box About the Import Bitmaps dialog box Merging a spectra channel Saving a spectral extraction Plotting spectra About the Spectra Plotting dialog box Radiometric quantity vs. wavelength graph Displayed spectra Graph options Plotting ranges Report Selecting a spectra library Changing the graph options Saving a spectra plot Opening the DEM Editing dialog box Editing a DEM Opening an existing mask Creating a mask Replacing the elevation values under a mask Filtering and interpolating DEM values Applying tool strategies for common situations in digital elevation models Adjusting pixel values for a lake Adjusting the pixel values for multiple lakes Compensating for forests and urban areas Neutralizing cloud-covered areas xi

14 Removing noise from a DEM Selecting the DEM layer Viewing the scatter plot for a layer Changing the input channel for the X and Y axes: Using the Scatter Plot dialog box Zooming into and out of a scatter plot Using the graph controls Changing the x and y view ranges Exporting a profile Working with legend and color controls Interpreting a profile table Changing the color of a channel Changing the profile vector color About the Change Color dialog box Printing without the mensuration bars showing Using the profile statistics Controlling the cursor Opening the GPS tool Using the GPS tool Updating the cursor position using the GPS receiver Inputting vector point data using the GPS receiver Inputting vector line or polygon data using the GPS receiver Using the ADAPT algorithm Converting RGB to pseudo-color Converting RGB to pseudo-color Opening the PCT Editing dialog box Adjusting the pseudo-color for single values Editing a value Selecting a basic color value Customizing range-based pseudo-color tables Using standard mode Keeping the original color values Selecting colors within the range Applying pseudo colors to pixel values in a raster Opening the Raster Editing dialog box Specifying a value Changing a default enhancement Applying a linear enhancement Zooming an image feature with an enhancement Adjusting toolbar enhancements Applying the Tail Trim option xii

15 Adjusting the amount of Tail Trim Decreasing the image contrast Decreasing the image brightness Enhancing images from the shortcut menu Opening the LUT editor Displaying a histogram in the LUT Editor Moving an entire histogram Using the LUT tools Using the LUT enhancement options Trace-editing a LUT histogram Comparing custom enhancements Applying a new look-up table to the corresponding image plane Working with spatial filters Opening the Filter dialog box Filtering under a mask Using low-pass filters Applying a gamma filter Using high-pass filters Creating custom filters Saving a filtered image to a new file Scaling images Scaling output data using Save As Available scaling methods Scaling output data Fusing image data Running the FUSE algorithm Running IHS and RGB Using the PANSHARP algorithm Using the raster calculator About the raster calculator Expression Edit View Raster Calculator toolbar Expression Calculator keys Output parameters Using the Raster Calculator to set output parameters Opening the EASI Modeling dialog box About the EASI Modeling dialog box Adding image and bitmap layers to a.pix file xiii

16 Using simple image models Understanding the basic modeling logic Adding a bitmap layer to irvine.pix Image layer variables Creating an EASI bitmap mask Understanding atmospheric correction Preparing data Transfer data to PCIDSK Reprojecting data Assembling data into a file Opening the Atmospheric Correction Configuration dialog box Setting up atmospheric correction parameters About aerosol types About standard atmospheres Opening the elevation information setup dialog box Calculating slope, aspect, sky view, and shadow Opening the band setup dialog box Matching band numbers to channel numbers Opening the Solar Calculations dialog box About Solar Zenith and Azimuth Calculating the solar zenith and azimuth About visibility About adjacency Determining the offset to surface temperature value Editing an existing calibration file to create a new file Opening the Define Haze and Cloud dialog box Automatically creating a mask Importing the masks from a file Editing the Cloud mask Editing the Haze mask Editing the Visibility layer Opening the Run Atmospheric Correction dialog box Running the correction Deriving additional data from the corrected imagery Opening the Leaf Area Index Model dialog box Selecting the equation for calculating the Leaf Area Index Changing the values for the fraction of photosynthetically active radiation (FPAR) equation Opening the Advanced Option dialog box Setting the parameters Setting the thresholds for the reference pixels Opening the Empirical BRDF Correction dialog box xiv

17 Selecting the BRDF equation Understanding vector layer types Unstructured vector layers About topological layers Thematic rasters Understanding vector editing in a math model area Adding a new vector layer Adding points to an active layer Adding a line or a polygon to an active layer Adding a rectangle or ellipse to an active layer Tracing a line on an active layer Digitizing 3-D vectors Performing tasks in the Attribute Manager About the Preferences dialog box Controlling the Attribute Manager cursor Setting a selected record statistics display Creating an unconnected table Restricting the layer so you cannot add shapes to it Viewing records Opening a file saved as an attribute Selecting and clearing records and fields Understanding vector layer type default fields Adding records to the Attribute Manager Adding new fields Setting the field definitions Changing an existing field to a geometry field Adding all appropriate geometry fields Updating the geometry Using find and replace in the Attribute Manager Creating a relational database Selecting all records that match a value in the current cell Selecting all records that do not match a value in a selected field Making a query by example Limiting the query to selected records Using the compute function Opening the Aggregate Attributes dialog box Performing a calculation Opening the Area Neighbors dialog box Reporting bordering areas Creating a chart from the Attribute Manager Opening the Z-value Transfer dialog box xv

18 Transferring Z-values from the vertices to a field Transferring Z-values from a field to the vertices Exporting layer attributes to a file Exporting the attributes to a text file Opening GeoRasters from the Attribute Manager Dissolving a boundary Adding function fields to output layers Working with shapes Selecting a single shape Selecting shapes within or partially within a circle Selecting shapes within or partially within a polygon Grouping shapes Ungrouping shapes Attaching shapes Separating shapes Creating buffers Creating buffers - step Creating buffers - step Editing vectors using the vector editing tools About the Vector Editing tool bar Selecting a shape Moving a vertex Moving several vertices together while maintaining their form Reversing vector direction Adding vertices Connecting lines Connecting polygons Cutting a line Cutting a polygon Extending a line Merging segmented lines Changing a line into a polygon Flipping a shape to its mirror image Spinning a shape free hand Spinning the shape precisely Separating overlapping shapes Moving the cursor to the start vertex Moving the cursor to the end vertex: Moving the cursor along vertices Moving the cursor to a vertex Displaying vertices xvi

19 Adding and removing: vertices Switching between coordinate systems Selecting vectors using spatial query tools Including an original selection in a spatial query Selecting fully contained shapes Selecting partially contained shapes Selecting all shapes within a specified distance Selecting all shapes fully within a distance Selecting intersecting shapes About the Overlay wizard Combining layers with a spatial overlay Using a statistical overlay Adding attributes to the statistical overlay output Using a suitability overlay Understanding weights in the suitability overlay Viewing data as a chart About chart types Creating a chart from the layer Defining the data to chart About Series In Designing the chart surround About the category field Resetting the chart to defaults Using the Chart Viewer Designing the chart legend Opening the X-axis or Y-axis Properties dialog box Customizing the axis heading Customizing the axis tick labels Opening the X-axis or Y-axis Properties dialog box Displaying grid lines along the axis Displaying ticks Opening the Title or Subtitle Properties dialog box Customizing the title or subtitle of the chart Opening the data labels properties Customizing the data labels Saving a chart Opening and deleting a chart Digitizing vectors with peripheral devices Registering a digitizing tablet Importing and exporting tablet registration Using a digitizing tablet xvii

20 Using the GPS tool Inputting vector point data using a GPS receiver Inputting vector line or polygon data using the GPS receiver Understanding representation Types of representation style tables Generating an indirect representation style table Editing the representation styles Selecting a style Changing style appearance Changing style parts Using an attribute as part of the style Opening the Set Style Attribute dialog box Setting the style attribute Selecting a symbol Labelling shapes Managing the labels Adding labels to a layer Setting label representation Changing labels Defining the design and layout for labels Defining which attribute to use for the label Setting the position for point layer labels Setting the position for line layer labels Setting the position for polygon and raster layer labels Designing a symbol Understanding the symbol working area Creating a symbol Creating a multi-part symbol Selecting a symbol from the symbol file Setting symbol representation Editing the symbol RST About the symbol file Save As dialog box Saving a project file Renaming a map Starting a new map Working with map properties Changing the paper size by dragging a resize handle Changing the paper size from the Map Properties dialog box Working with areas Scaling an area Rescaling an area xviii

21 Setting area properties Setting area properties Opening the Math Model Area Properties dialog box Setting Math Model Area properties Working with surrounds Creating a surround Setting a default surround element Setting a default quick style Setting surround element properties About neatlines Setting the position of a neatline in relation to an area Setting specific extents for a neatline About borders Changing border style and proximity to neatline About grids Changing grid pacing and proximity to neatline Changing the style and layout of the grid Changing the location and style of the grid headings Changing the location and style of the grid labels About legends Setting the number of columns and designing a border for a legend Adding a title to the legend Adding styles to a legend Organizing sections in a legend Creating a design for sections in a legend Customizing a section layout Organizing legend columns Adding a picture to a map About north arrows Setting the angle and style for a true North arrow Adjusting the position of a north arrow label Setting the angle and style for the magnetic north arrow Setting the angle and style for the grid north arrow About scale bars Determining the style and position of the title for the scale bar Selecting a scale bar type Setting the divisions for the scale bar Labeling a scale bar with a unit of measurement and setting a zero tick Setting subdivisions for a scale bar Specifying which divisions to subdivide Designing a Line and Tick scale bar xix

22 Designing a single, double, or triple scale bar Adding a map title to an area Adding text to a surround Setting the updating behavior Setting the offset (not available for neatline, border, and grid) Setting a grid starting point Selecting an existing quick style Removing a custom quick style from the list Creating a custom quick style Creating an index for a project, you must provide Adding a default index to a map Indexation properties Setting general parameters for an index Adding or change the index title Opening an indexation parameter file Setting up an index Setting the spacing for rows and columns Setting the count for rows and columns Setting headings for rows and columns Setting a RepCode for a grid heading Setting a RepCode for grid lines Filtering an index Making a word exclusion list Generating an index list Using the Verification Mode option Setting advanced indexation properties The prefixes list follows a set of rules Creating or editing a prefixes list Using the Swap Prefixes option Saving an indexation file Adding text to an index Setting the text color Setting the text style Using the New Text tool Printing a map Selecting printer options Selecting page layout options Printing color separations Opening the Export Map dialog box Exporting a map or chart as an Adobe Illustrator file Exporting a map or chart as a JPEG xx

23 Exporting a map or chart to a JPEG 2000 file Exporting a map or chart to PCIDSK Exporting a map or chart to TIFF Exporting a map or chart to BMP Exporting a map or chart to an HP RTL file Exporting a map or chart to EMF Viewing overlapping layers from a Web mapping service xxi

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25 Focus and the other Geomatica applications. Chapter 1 Using the Focus online help The Focus HTML online Help system provides basic Help topics for using Focus and online references for the Focus tools and processes you will need to use when you do your work. Geomatica Help includes a technical reference library for background information and extensive online list of data formats you can use with the many PCI GeoGateway features in Focus. You can also contact PCI or visit the Corporate Web site for more specific help and support. Using technical references The Geomatica online Help system includes Technical References you can access from Focus online Help. Technical references are available for: GeoGateway formats: Provides information on working with large files, the PCIDSK file structure, and supported file formats. Projection Reference: Provides a complete list of projections supported by Advanced Hyperspectral: Contains detailed technical information on hyperspectral data and how you can use it with Focus and the other Geomatica applications. For information on using the Focus hyperspectral visualization tools, see the Focus Online Help and the Focus User Guide. Using the GDB formats reference GeoGateway (GDB) is a technology allowing programs to uniformly access data in many different geomatics file formats without having to translate them before you use an application. GeoGateway lets you access imagery, vectors, attributes, projections and auxiliary information. All important data types, and access approaches from the generic GeoGateway Data Model are implemented within the GeoGateway library. Not all file formats support all data types, or access approaches. Only PCIDSK, the format on which the GeoGateway Data was modelled, supports all possible data types. Many formats have limitations that may effect your productivity when using Focus and other Geomatica applications. The GDB Formats reference topics describe each format, including any limitations. The complete list of DGB formats is included in the Geomatica online Help system under the Supported File Formats topic. You can open a Help screen for a specific format from the main 23

26 Supported File Formats screen by clicking the name of the format in the supported formats list. 24

27 Chapter 2 Working with Focus Like all products, Focus is designed to work with dozens of data formats through GeoGateway and to take advantage of the PCIDSK file format. There are several instances when you should change your data to PCIDSK so you can take advantage of all of the features offered in Geomatica. under both the Files tab and the Maps tab. You can choose files from the File Selector dialog box, which is a standard Windows panel that also allows you to choose from data types in the GeoGateway file list (GDB formats). For more information on the File Selector dialog box, see "Common Utilities" in the Geomatica online Help. The following image shows the main Focus interface: You should convert your data files to PCIDSK format when: The original format does not support auxiliary information, such as georeferencing, look-up tables, pseudo-colour tables, and vectors. The original format cannot be updated. You want to use your files in PACE or XPACE programs. Geomatica also contains a certified implementation of the NITF standard enabling you to view, to format, and to export digital imagery and imagery-related products; Geomatica is, however, not NITF certified. Opening a file You can open files in Focus from the File menu, from the toolbar, or from shortcut menus in the Focus control pane When you open data files, they are listed in the Files tree in the control pane and all files and layers are available. For more information about elements in the Focus 25

28 interface, see Understanding the Focus control pane on page From the File menu, click Open. You can also right-click in the Maps control pane and click Open. 2. In the File Selector dialog box, locate and select your data files. 3. Click Open. The image data opens in the view pane. The first three image channels are automatically selected. The file components are listed in the Maps and Files control panes. If the file you opened does not have raster data, the first vector layer opens in a new map. Note: For colour images, TM Bands 1, 2, and 3 representing the red, green, and blue (RGB) image channels, are listed in the Maps tree under New Area. When you open an image containing a math model segment, you can choose to use the a georeferencing or math model. For more information, see Using a math model with images on page 40. Adding data to a project You can add data to a project in several ways. The method you use may depend on your objectives. You can use the Files menu to add as many new files to a project as you want in the same way as you would any other Windows-based application. Focus also provides an Add Layer Wizard to make adding data easier, see Using the Add Layer wizard on page 26. You can also add files to open data. For example, you can add new vectors to an Area already in use or you can create a new empty layer and add new data to it by dragging data from another Area or from a different database using the Add Layer Wizard. When you add more data to a project, it is automatically added to the Focus Maps tree in an active Area. 1. In the Maps tree, right-click a Map and click New Area. 2. Drag the data you want to move into the new Area. 3. Save the project. You can also add files from the Files tree to the Maps tree from an open database. Using the Add Layer wizard When you want to add layers from other GeoGateway-supported data sets, you can add vector, RGB, grayscale, pseudo-color, and bitmap layers to a project with the Add Layer Wizard. The Add Layer Wizard helps you locate the exact layers you want and guides you through the process of adding the layer types you specify. When you move to the next step in the wizard, the commands shown in the lower part of the dialog box change according to the data type you are adding. When 26

29 you use the Add Layer Wizard, you do not need to have an active Area in the Maps tree; the Wizard creates a new layer automatically. 1. In the Maps tree, right-click the area where you want to add a layer and click Add. You can also click Add from the Layer menu. 2. From the Add Layer Wizard, choose a layer type option and click Next. 3. From the Files available list, select the data file containing the raster channels you want to use. If the raster file you want to use is not listed, click Browse, navigate to the file you want, and click OK. When you have selected a file in the Files available list, only channels of the specified type are listed in the The following vector segments are available list. For example, only bitmap channels are listed if you have selected bitmaps as the layer type you want to add. 4. From the The following vector segments are available list, select the channel you want to use in your layer. 5. Click Finish. Understanding the Focus control pane When you begin a work session, a Map, Area, and layer are automatically listed in the Maps tree using default file names and paths. By default, new Map layers are labelled Unnamed Map. Both the Map and layer levels show the name and path of the file you have opened. The Area level is named New Area by default. You can rename each level and each layer as needed. You can include files of almost any format in your project. In some cases, you may need to convert your file formats to the PCIDSK. Maps Are the element at the top of the hierarchy. This is the workspace that holds all of the data for your work, such as the image, surrounds, and indexes. You can have more than one map in a project. The Map represents the extents of the print page for your project. You can adjust the map size to control the size of your printed output or adjust the size and position of the image relative to the canvas. Areas Hold the file boundaries for either image or vector layers. You can include several layers and segments for a geographical region and you can have many areas in a Map. Each Area has a unique georeference system. When an image or vector layer is added to an area, it is automatically scaled and georeferenced to that Area. Layers Hold the data displayed in the view pane. Layers are composed of segments and can be rearranged in the Maps tree to change the image in the view pane. You can change the order of layers by dragging them up or down the Maps tree. When you move a layer, you also move 27

30 the segments within it. Segments Are all of the components that make up a layer, such as rasters, vectors, bitmaps, and look-up tables (LUT). The files, listed in the Maps tree, are a hierarchy of elements that make up a project. Maps tree elements have common properties that you can control from the Maps and Files tree, menu bars, and shortcut menus. Using the Maps and Files trees You can create, select, read, and write both image and auxiliary information to the items listed in the Maps and Files trees. The control pane uses the GeoGateway library to access both image and auxiliary information within your data files. GeoGateway makes it possible for you to interchange different file types, including third-party file formats. To access a file, select it in the Files tree. Changing the layer priority The Maps tree lists the areas, layers, channels, and segments that make up the image in the view pane. The Maps tree components are stored in your system memory. You can hide an item in the Maps tree by disabling the check box to the left of the item. You can also change the priority of a layer by dragging it up or down the Maps tree. Layer priority can cause one layer to mask another in the view pane. If you cannot see a layer that should be visible, check the layer priority. 1. In the Maps tree, click an Area layer. 2. Drag the layer up or down the Maps tree. A black line shows the layer position. You can move an entire area, including associated components, in the same way. Viewing layer properties You can view the properties for any Map, Area, or layer. For more information about properties, see the following: Managing data properties on page 35 Using the File Properties dialog box on page In the Maps tree, click a Map icon. 2. From the View menu, click Properties. For information on working with layers, see Using the Layer Manager on page 31. Viewing auxiliary data The figure below shows some of the contents of a.pix file, grouped by data type, in the Files tree. You can show or hide the vector and bitmap segments, listed in the Files tree, in the view pane. 28

31 The Add Image Channels dialog box opens when you right-click an unlocked file in the Files tree and lets you set the following attributes: The Files tree lists data saved to your hard disk Like the PCIDSK format, Focus keeps image channels and auxiliary data segments in the same place. The data listed in the Files tree is stored in the source file on your system hard disk. Some of the data types, listed in the Files tree, are not viewable as image components. The same list can contain other auxiliary data types such as LUTs, pseudo-color tables (PCT), and signatures. You can use the Focus software tools and dialog boxes to work with these data types. Adding image channels You can add 8-bit, 16-bit signed, 16-bit unsigned, or 32-bit real image channels to a selected PCIDSK file. Bit depth (also called pixel depth) refers to the range of numeric values stored in image layer data. The range of numbers each pixel can store increases with bit depth. About the Add Image Channels dialog box Supported bit depths are: 8-bit: 0 to bit signed; -32,768 to + 32, bit unsigned: 0 to 65, bit real: approximately +/-1.2E-38 to 3.4E+38 Channel Types: Lists the supported image pixel depths. Existing: Displays the number of image channels for each pixel depth in the selected file. Channels to Add: Lets you specify the number of image channels of each type that you want to add to the source file. When your source PCIDSK file channels are arranged as either band sequential or file interleaved, new channels are added to the end of the file. When your files are pixel interleaved, the new channels are added in groups of pixel depth. Pixel depth groups are ordered by size. For example, when you add 8-bit channels to an existing pixel interleaved file with 16-bit unsigned channels, the 8-bit channels are listed first. Existing 16-bit unsigned channels are renumbered as subsequent channels. 29

32 Combining layers A combined vector layer amalgamates several vector layers into one. For example, one vector layer covering the eastern US can be combined with another layer covering the western US to produce a virtual single layer for all of the US. When you combine layers, data is not duplicated, it is linked. The combined layer does not store data but acts as a pointer to the source data. You can combine vector layers from your current data files and from other source files with a two-part process to locate and choose the data you want to combine. 1. With at least two PCIDSK files open in the control pane, click the Files tab. 2. In the Files tree, right-click the file folder icon and click New and then click Combined Vector Layer. 3. In the Combined Layer dialog box, click Browse. 4. From the Select Layer dialog box, select a file from the File list box. 5. Select an available layer from the Layers available list. 6. Click OK. The layers and common columns are listed in the Combined Layer dialog box. The Layer list shows two or more entries that you can combine. The Common attributes list identifies the columns (fields/attributes) that will make up the combined layer doesn't require any action. Only columns that are present in all layers of your inputs are listed. 7. In the Combined Layer dialog box, select a layer and click OK. A new layer is added under the files listed in the Files tree. You can view the new layer and see the combined data in the view pane. You can also open the Attribute Manager to see all of the combined shapes. Layers common to both input layers are listed twice. For more information, see the following: About the Combined Layer dialog box on page 30 About the Select Layer dialog box on page 31 About the Combined Layer dialog box The Combined Layer dialog box provides a list of layers and common columns in separate windows that allow you to combine layers. Layer List: Shows the layers you have chosen from the Select Layer dialog box. Browse: Opens the Select Layer dialog box, allowing you to choose layers and source files. (See About the Select Layer dialog box on page 31 ) Remove: 30

33 Removes a selected layer from the Layer list. Common Columns List: Shows columns that are common to layers in the Layer list. About the Select Layer dialog box The Select Layer dialog box lets you choose the files containing the layers you want to combine. File List: Shows the files currently in a project from which you can select layers. Layer List: Shows the layers within selected files in the Files list. Working with project files Focus project files (.gpr files) provide a way for you to organize data for complex projects in one large file. A.gpr file not only stores Maps, Areas, and layers, but also includes all path information to data, viewing preferences, such as the last zoom level you worked at, and all associated Map elements. A.gpr file can also include multiple Maps, Areas, and all associated layers. Files included in a project are listed in the Files tree in the control pane. All files and layers are available for use in a project at any time. You can use any of the Focus viewing and editing options when working with.gpr files. You can also manage RGB and grayscale layers within project files with shortcut menus in the Maps and Files panes. When you right-click an object in the Files tree, a shortcut menu lists the available commands for working with that data type. For example, right-clicking a file folder icon opens a shortcut menu listing several commands for managing files. Right-clicking an RGB or grayscale layer opens a shortcut menu listing commands for managing the layers as a data file and for adjusting attributes, statistical properties, and overviews for that layer. Saving a project When you work with multiple files, you can save your work as a project using the file name of your original data files or save your project under a new file name. 1. From the File menu, click Save Project or Save Project As. 2. In the File Selector dialog box, navigate to the folder where you want to store the project file. 3. Type a name for the project in the File name box. 4. Click Save. To save your project while you are working on it, click File and then click Save Project. Using the Layer Manager 31

34 The Layer Manager lists layer properties in a table format that shows properties for each object in the map and the hierarchical structure of Maps, Areas, and layers. For surrounds, the Layer Manager only displays the surround elements. This tool is useful when you are trying to manage a large combination of data layers, rasters, and vectors when making a map. Using the Layer Manger, you can control the vector layer hierarchy to ensure that one project layer does not cover another. In the Layers menu, click Layer Manager. Changing layer properties In the Layer Manager table, object names are listed in rows. Object properties are listed in the table columns. Like the Maps and Files trees, icons are shown beside each object in the Name column. Properties in the Layer Manager show the state of layers in the current project. They can be changed according to the editable items for the specific layers you are using. Changes in the Layer Manager are automatically shown in the Maps tree. A layer must be open and the Map must be active to make changes. The check box indicates active layers and maps. The following lists the Layer Manager table columns and explains the property cells you use to show, edit, open, and active properties for layers. Name: You can edit this column and change the names of your layers. Layer Visible: Checked cells are visible layers. When the check box is disabled, the layer is not visible. Legend Items Visible: Checked cells are Legend items that are visible. They are similar to the Layer Visible column but only apply to layers in the legend. Read Only: Checked layers are read-only. When a layer is read-only, a red x will appear beside the layer under the Maps tab. Layer Priority: Cell numbers show the layer priority. A layer that is assigned a higher priority will be displayed on top of a layer with a lower priority. (See Changing the layer priority on page 28 ) Zoom Scale Active: Checked layers can be assigned zoom scale values. Min Zoom Scale: Minimum zoom scale value. As map scales go, this parameter, X, is considered to be 1: X. Max Zoom Scale: 32

35 Maximum scale zoom value. As map scales go, this parameter, X, is considered to be1: X. Selectable: Objects are selectable Transparency Active: Checked cells can be assigned a transparency value. When this check box is enabled, the values in the Transparency Value columns are active and the results are shown in Focus. Transparency Value: The pixel value entered here will become transparent, allowing you to see imagery under it. To properly assign transparent values to a three-channel RGB image, use the following format: R10G20B100. In this example, pixel value 10 will become transparent for the red band, 20 for the green band, and 100 for the blue band. For grayscale images, you need only specify a singe value. For example: 10. The pixel value of 10 would become transparent in your grayscale image. Opacity Active: When this check box is enabled, the values in the Opacity% column become active and the results are shown in Focus. Opacity%: Sets the opacity level. For example, 100% opacity shows the entire image. Layers beneath cannot be seen. With a setting of 0%, none of the image is shown. You can see all of an image beneath the layer. View No Data Value: Shows Null values. No Data Color: When there are #No Data# values in your working file, The No Data Color column lets you assign a color for viewing your No-Data pixels. Using the Zoom Scale Active feature When image data is opened, it is viewed at a specific scale (for example, 1:150000). The Zoom Scale function lets you specify the resolution for activating specific layers of imagery. When the current viewing resolution is in between the minimum and maximum values that you have set for a layer, the image becomes visible. When the current viewing resolution is outside the minimum and maximum range you have set, the layer is not visible. The Zoom Scale tool is useful when looking at both high-resolution and low-resolution imagery of the same area. For example, if you have a 30m Landsat image, a 10m SPOT image and 1m aerial photo, all covering the same area, you can view the Landsat image in Focus, but the aerial photo cannot be used because its pixels are too small to render an accurate image. When you are zoomed into a ground feature using the aerial photo, the 33

36 Landsat and SPOT scenes cannot be used because their pixels are too large. Using the Zoom Scale function you can set the zoom scale to deactivate the Landsat image when you are zoomed into the aerial photo, or deactivate the aerial photo when you zoomed out looking at the Landsat scene. The following table shows the settings to use for the example above. Table 1. When you open a raster that contains a rotation, you will be prompted to choose whether you want the raster to display as a rectangular grid (Raster Up) aligned with the Area or with the rotation from the file (North Up). With the North Up option, the rotated raster opens as any other raster. In the Focus view pane the raster may appear turned in the Area since it has been corrected so North is at the top of the viewer. A rotated raster as North Up Image Min Zoom Scale Landsat (30m) 1: : Spot (10m) 1: : Max Zoom Scale Aerial Photo (1m) 1: : About rotated rasters Most raster (image) formats consist of a rectangular grid of pixels. However, some formats support raster rotation, which can display the raster as spun in a particular position, usually so North is at the top of the viewer. Currently, PIX, GeoTIFF, MrSID and JPEG2000 can store rotations internally. TIFF (with.tfw), JPEG (with.jpw), BIP (with.biw), BIL (with.blw) and NITF (with.niw) support rotations via their associated world file. Other formats may support rotations via a.pox file. With the Raster Up option, the Area is rotated to counteract the effect of the rotation in the file so the first pixel in the data is in the top left corner of the Area. In the Focus view pane the raster appears squared to the Area. A rotated raster as Raster Up 34

37 When you create a map with a rotated Area (Raster Up), two surround elements are affected: Grid and North Arrow. You cannot create a grid in a rotated Area. When you create a North Arrow in a rotated Area, the North Arrow will be rotated by the amount set in the Area properties. Managing data properties Properties are applied to data elements you have added to your work and file elements that are saved to your hard disk. New and saved elements are listed under the Maps tree. Files, saved to disk, are listed under the Files tree. (See Using the File Properties dialog box on page 57 ) Properties are also applied to metadata files such as look-up tables, pseudo-color tables, ground control points, and signatures. When you are working with either project files or.pix files, you can use the properties to carry out basic operations like renaming and removing data. Properties dialog boxes have tabs with layer-specific settings that you can adjust for the data type you are working with. Properties dialog boxes always show information specific to the file and the file type you have chosen. Information and inputs vary depending on the type of layer you have chosen. 1. In the control pane, click the Maps tab and select a layer. 2. From the View menu, click Properties. You can also right-click a layer and click Properties, or you can double-click a layer. About the Map Properties dialog box The Map properties dialog box allows you to change several attributes for your Map. You can re-name maps, review file information, and a select paper size and orientation for your map. You can also choose a Representation Style Table (RST). (See General tab on page 35 ) General tab Under the General tab, you can change generic information about your Map and read other file information. (See Working with map properties on page 365 ) Description: Lets you change the file name or description appearing in 35

38 the Maps tree. File Name: Reports the name of the Map file for the properties you are viewing. Created: Reports the date the file was created. (See Page Setup tab on page 36 ) Page Setup tab Under the Page Setup tab you can make page selections that change the Map page orientation and size. You can see your changes in the view pane from the Map view mode. Your changes also affect the way your page is printed. For more information, see the following: Changing the paper size by dragging a resize handle on page 365 Printing a map on page 404 Orientation: Lets you select the way your Map appears on paper. Choose either the Portrait or the Landscape option. Portrait: Orients the map vertically Landscape: Orients the map horizontally Paper Size: Allows you to choose from a list of standard paper sizes or lets you create a custom size. You can choose from the following paper size options: US Letter US Legal A0 A1 A2 A3 Tabloid A4 Tabloid A4 Letter A5 Letter B1 (ISO) B4 (ISO) B5 Letter B 11" X 17" C 17" X 22" D 22" X 34" E 34" X 44" Custom Width: The Width box shows the dimensions of the standard paper size you have chosen or allows you to enter a custom paper width of your own. Height: 36

39 The Height box shows the dimensions of the standard paper size you have chosen, or allows you to enter a custom paper height of your own. (See Default RST tab on page 37 ) Default RST tab Under the Default RST tab you can select a Representation Style Table to use as the default for your map. RSTs that are associated with the map are listed in the window. You can browse to locate and add an RST to your map. (See Understanding representation on page 352 ) About the Area Properties dialog box The Area properties dialog box allows you to change several attributes for an Area. You can re-name maps, review file information, and change the Area scale, layout, and projection. You can also choose a new earth model for the Area projection. (See Setting Math Model Area properties on page 370 ) Changing the values on the Area properties dialog box does not change the data in the file on disk, it changes the properties of the Area only. (See General tab on page 37 ) General tab Under the General tab you can change generic information about your Area and preview the position of your area in relation to your map. Description: The Description box lets you change the Area name or description appearing in the Maps tree. Show Outline: The Show Outline option outlines the Area in the view pane. Scale: The Scale box allows you to change the scale of your Area to several standard scales or to a custom scale. You can choose from the following scale options: 1: : : : Custom When you choose Custom from the scale list, you enter your custom scale in the scale box. Preview: The Preview area allows you to see the scale and orientation of your Area relative to your map. (See Layout tab on page 38 ) 37

40 Layout tab The Layout tab lets you change the Area representation, position, and size. You can also view position and size changes in a preview window. Representation: Lets you change the Area scale factor and the Area priority. Scale Factor: Changes the Area scale factor. (See Scaling an area on page 367 ) Priority: Changes the Area priority relative to other Areas in your project or file. (See Changing the layer priority on page 28 ) Position: Allows you to move your Area relative to the Map and to select a unit of measure for your Area. Left: Allows you to change the Area position left or right. Bottom: Allows you to change the Area position up or down. Size: Allows you to control the width and height of your Area. Width: Changes the width of the Area. Height: Changes the height of the Area. Automatic resize: Resizes your Area automatically. Preview: Allows you to see the position and width and height changes for your Area relative to your map. (See Projection/Extents tab on page 38 ) Projection/Extents tab The Projection/Extents tab allows you to change the definition of the Area#s projection, change the bounds of the Area, and rotate the Area. Changing the projection's definition does not change the projection of the Area. To change the projection, see Reprojecting files on page

41 Coordinate System: The Coordinate Systems list displays the coordinate system for your area. Other This Projection Opens this panel Set the Projection Definition The available coordinate systems are Pixel UTM Long/Lat Meter Foot SPCS Other Earth Model: The Earth Model button opens the Earth Model dialog box, where you can choose from a list of data and ellipsoids to define a coordinate system for an area. More: The More button opens projection definition dialog boxes, where you can select a projection definition for the Area. The More button is active if you select UTM, SPCS, or Other from the Coordinate System box. A different projection panel opens under different conditions. Table 2. Bounds: The Bounds box allows you to show the bounding coordinates of you file in either geocoded (Eastings and Northings) or geographic (latitude and longitude) units for UTM, SPCS and Other coordinate systems. Bounding coordinates are not shown with the Pixel option. Long/Lat displays the bounding coordinates in geographic units only. Meter and Foot displays the bounding coordinates in geocoded units only. Upper left: The Upper Left boxes show the X, Y coordinates for the upper left corner of the Area. Values are in the units of the selected coordinate system. Lower Right: The Lower Right boxes indicate the X, Y coordinates for the lower right corner of the Area. Values are in the units of selected coordinate system. Rotation: This Projection UTM SPCS Opens this panel Zone and Row State Plane Zone The Rotation boxes indicate the amount the Area is rotated to display a rotated raster so the first pixel in the data is in the top left corner. For more information, see About rotated rasters on page

42 Visual Clipping: The visual clipping section lets you choose a clip region from a list of clips that fall within your Area. Define Clip Region: The Define Clip Region button opens the Define Clip Region dialog box. Enable: The Enable option is available after you have chosen a clip region from the Define Clip Region dialog box. The Define Clip Region Panel: Allows you to choose a clip region from a list of data that falls within the area.(see Opening the Clipping/Subsetting panel on page 151 ) 1. Right-click New Area and click Properties. 2. In the Area Properties dialog box, click the Projection/Extents tab. 3. Click Define Clip Region. 4. From the Define Clip Region dialog box, choose the layer that you want to use to define the extents of the clip region from the Clipping Layer list box. 5. Click OK. 6. From the Visual Clipping area of the Area Properties dialog box, enable the Enable check box. 7. Click OK. Using a math model with images A math model is a mathematical relationship used to correlate the pixels of an image to correct locations on the ground accounting for known distortions. Different sensors require different math models to correct the distortions. Math models can come from a number of sources. QuickBird, Ikonos, and OrbView imagery can come with a text file that contains rational function coefficients called Image Geometry Model (IGM) or Rapid Positioning Capability (RPC), which Focus uses to define a Rational Functions math model. You can build a math model in OrthoEngine and export it as a segment in the file containing a raw image. Geomatica also contains algorithms that can build math models. These algorithms can be run in Modeler, EASI, or in the Algorithm Librarian: SATMODEL: to compute Toutin's Model, which is a rigorous satellite math model. RSMODEL: to compute the ASAR and RADARSAT-specific math model. RFMODEL to compute the Rational Functions math model. AVMODEL: to compute the math model for AVHRR imagery. OEMODEL: to compute any model from an OrthoEngine project file. When you open an image containing a math model segment, you can choose to use the file georeferencing or math model. When you choose file georeferencing, the 40

43 image opens in a layer in an Area using the georeferencing saved in the file or pixel-based georeferencing if no georeferencing is available. When you choose the math model, the image is displayed as a layer and the Area is changed to a Math Model Area. In the Math Model Area the image is displayed without correction in the viewer, but accurate ground coordinates are calculated for each pixel using the pixel and line coordinates, the math model, and the digital elevation model (DEM), or an approximate elevation value that you provide. The advantage of using the math model is that you can display geocoded coordinates, overlay geocoded vectors, and digitize geocoded three-dimensional vectors on the raw image instead of going through the potentially time-consuming, labor-intensive process of orthorectifying or geometrically correcting the imagery. This process is also known as mono-restitution. 1. Open an image, see Opening a file on page If you want to use the georeferencing saved in the file, click File. 3. If you want to display the image using the math model associated to the file, click Math Model. 4. Click OK. Using the math model for georeferencing When a math model is used to set the georeferencing, the Area becomes a Math Model Area. In a Math Model Area, the image is displayed without correction in the viewer; accurate ground coordinates are calculated for each pixel using the pixel and line coordinates, the math model, and the digital elevation model (DEM), or an approximate elevation value that you provide. For more information, see Using a math model with images on page In the Source of georeferencing list, select the segment containing the math model that you want to use in the Area. The projection, bounds, upper-left coordinate, lower-right coordinate, and pixel sizes are displayed under Georeferencing Information 2. To use a DEM as the source for your elevation values, click DEM. In the File box, type the path and file name of the DEM or click Browse to select the file. In the Layer list, select the layer that contains the DEM. In the NoData (background) value box, type the value that represents the pixels that lie outside the DEM area so they are not mistaken for elevation values. 3. To use an estimate of the elevation instead of the DEM, click Approximate elevation. In the Elevation value box, type the elevation value that you want to use. If you do not enter an elevation value, a value of 0 meters (Mean Sea Level) is used by default. 4. In the Elevation reference box, select Mean Sea 41

44 Level (MSL) if the elevation values were calculated based on the geoid; select Ellipsoid (ELL) if the elevation values were calculated based on an ellipsoidal model of the Earth. 5. In the Elevation units box, select a measurement unit for the elevation values. 6. Click OK. About the Math Model Area Properties dialog box The Math Model Area properties dialog box allows you to review file information and change the scale and layout of a Math Model Area. The georeferencing of the Math Model Area is based on a math model segment associated with a raw image rather than remaining pixel-based. For more information, see Setting Math Model Area properties on page 370 ). (See General tab on page 37 ) General tab Under the General tab, you can change generic information about your Math Model Area and preview the position of your area in relation to your map. Name: The Name box lets you change the Math Model Area name or description appearing in the Maps tree. Show Outline: The Show Outline option outlines the Math Model Area in the view pane. Scale: The Scale box allows you to change the scale of a Math Model Area to several standard scales or to a custom scale. You can choose from the following scale options: 1: : : : Custom When you choose Custom from the scale list, you enter your custom scale in the scale box. Preview: The Preview area allows you to see the scale and orientation of your Math Model Area relative to your map. (See Layout tab on page 38 ) Layout tab The Layout tab lets you change the Math Model Area representation and position. You can also view position changes in a preview area. Representation: 42

45 Lets you change the Math Model Area scale factor and the Math Model Area priority. Scale Factor: Changes the Math Model Area scale factor. (See Scaling an area on page 367 ) Priority: Changes the Math Model Area priority relative to other Math Model Areas in your project or file. (See Changing the layer priority on page 28 ) Position: Allows you to move your Math Model Area relative to the Map and to select a unit of measure for your Math Model Area. Left: Allows you to change the Math Model Area position to the left or right. Bottom: Allows you to change the Math Model Area position up or down. Size: The Size section is always disabled in a Math Model Area. The width and height of your Math Model Area are determined by the file. Automatic Resize: Automatically enlarges the extents of the Area to accommodate the extents of the data. Preview: The Preview area allows you to see the position and width and height changes for your Math Model Area relative to your map. (See Projection/Extents tab on page 38 ) Projection/Extents tab The Projection/Extents tab allows you to view the Math Model Area projection and select a clip of image data that falls within the area. It lists the file that contained the math model segment, the name of the segment, and the source for the elevation values. Projection The coordinate system used in your Math Model Area is displayed. Bounds The Bounds list allows you to show the bounding coordinates of your file in either geocoded (Eastings and 43

46 Northings) or geographic (latitude and longitude) units for UTM, SPCS, and other coordinate systems. Upper left The Upper Left boxes show the X, Y coordinates for the upper-left corner of the file. Values are in the units of the selected coordinate system. Lower Right The Lower Right boxes indicate the X, Y coordinates for the lower-right corner of the file. Values are in the units of selected coordinate system. Visual Clipping The Visual Clipping section lets you choose a clip region from a list of clips that fall within your Math Model Area. Define Clip Region The Define Clip Region button opens the Define Clip Region dialog box, which allows you to choose a clip region from a list of data that falls within the Math Model Area. (See Selecting a clip region on page 158 ) Enable: The Enable option is available after you have chosen a clip region from the Define Clip Region dialog box. About the RGB Layer Properties dialog box The RGB Layer Properties dialog box allows you to change general properties, switch source images and lookup tables, adjust display properties, and set a zoom scale for your RGB layers. (See General tab on page 44 ) General tab Under the General tab, you can change general information about your file and read other file information. Description: The Description box lets you change the file name or description appearing in the Maps tree. Read Only: The Read Only option lets you change the Read/Write properties of the RGB layer. Visible: The Visible option makes the RGB layer visible in the view pane. Priority: The Priority box changes the priority of the RGB layer in your project or file. (See Changing the layer priority on 44

47 page 28 ) Resample Method: Allows you to select a resampling method for displaying the raster in the Focus view pane. The resampling does not change the data itself, it is only used to determine how to display the raster on your screen. You can choose from the following resample methods: Nearest Neighbor Bilinear Interpolation Cubic Convolution Layer Enhancement: Reports enhancements associated with the RGB layer. (See Changing a default enhancement on page 244 ) (See Source Images tab on page 45 ) Source Images tab Under the Source Images tab, you can select a new file and a new image for the red, green, and blue channels. RedImage: Lets you select a new file and layer for the red image channel. File: Allows you to choose a different file from a list of files you have open in Focus. Layer: Lets you to choose a layer from the file you chose from the RedImage File box. GreenImage: Lets you select a new file and layer for the green image channel. File: Allows you to choose a different file from a list of files you have open. Layer: Lets you to choose a layer from the file you chose from the GreenImage File box. BlueImage: Lets you select a new file and layer for the blue image channel. File: Allows you to choose a different file from a list of files you have open. 45

48 Layer: The layer list lets you to choose a layer from the file you chose from the BlueImage File box. (See Source LUTs tab on page 46 ) Source LUTs tab Under the Source LUTs tab, you can select a new file and a new look up table for the red, green, and blue channels. RedLut: Lets you select a new file and look up table for the red image channel. File: Allows you to choose a different file from a list of open files. Layer: Lets you to choose a LUT from the file you chose from the RedLut File box. GreenLut: Lets you select a new file and look up table for the green image channel. File: The File list allows you to choose a different file from a list of files you have open in Focus. Layer: Lets you to choose a layer from the file you chose from the GreenLut File box. BlueLut: Lets you select a new file and look up table for the blue image channel. File: Allows you to choose a different file from a list of files you have open. Layer: Lets you to choose a layer from the file you chose from the BlueLut File box. (See Display tab on page 46 ) Display tab The Display tab has controls for changing the transparency and opacity of the RGB layer and for viewing #No data# values when they are included in an RGB layer. 46

49 Vector layers placed below a raster transparency in the Maps tree appear in the view pane but are not supported for printing. Transparency: Makes the Value boxes available. Red Values: Lets you enter a value or a range of values for red channel transparency. Green Values: Lets you enter a value or a range of values for green channel transparency. Blue Values: Lets you enter a value or a range of values for blue channel transparency. Opacity: Makes the Opacity slide control available for changing the opacity of the RGB layer. View 'No Data Value': When an RGB layer contains 'no data' values, the View 'No Data Value' option is available. When you choose the View 'No Data Value' option, you can select a color from the color list for displaying them in the view pane. (See Display within Zoom Scale tab on page 47 ) Display within Zoom Scale tab The Display within Zoom Scale tab allows you to set independent zoom limits for your RGB layer. When you zoom the view pane above the maximum scale or below the minimum scale, your RGB layer is no longer visible in the view pane. Minimum Scale: Lets you enter a minimum zoom scale. Maximum Scale: Lets you enter a maximum zoom scale. Current Zoom Scale: Reports the current zoom scale for the RGB layer. About the Grayscale Layer Properties dialog box The Grayscale Layer Properties dialog box allows you to change general properties, switch source images and lookup tables, adjust display properties, and set a zoom scale for a grayscale layer. (See General tab on page 48 ) 47

50 General tab Under the General tab, you can change generic information about your file and read other file information. Description: Lets you change the file name or description for the grayscale layer appearing in the Maps tree. Read Only: Lets you change the Read/Write properties of the grayscale layer. Visible: Makes the grayscale layer visible in the view pane. Priority: Changes the priority of the grayscale layer in your project or file. (See Changing the layer priority on page 28 ) Resample Method: Allows you to select a resampling method for displaying the raster in the Focus view pane. The resampling does not change the data itself, it is only used to determine how to display the raster on your screen. You can choose from the following resample methods: Nearest Neighbor Bilinear Interpolation Cubic Convolution Layer Enhancement: Reports the enhancements associated with the grayscale layer. (See Changing a default enhancement on page 244 ) (See Source Images tab on page 48 ) Source Images tab Under the Source Images tab, you can select a new file and a new image for the grayscale channels. File: Allows you to choose a different file from a list of files you have open. Layer: Lets you to choose a layer from the file you chose from the grayscale file box. (See Source LUTs tab on page 48 ) Source LUTs tab Under the Source LUTs tab, you can select a new file and a new look up table for the grayscale channel. LUT: 48

51 Lets you select a new file and look up table for the grayscale layer. File: Allows you to choose a different file from a list of open files. Layer: Lets you to choose a LUT from the file you chose from the LUT file box. (See Display tab on page 49 ) Display tab The Display tab has controls for changing the Transparency and Opacity of the grayscale layer and for viewing #No data# values when they are included in a grayscale layer. Vector layers placed below a raster transparency in the Maps tree appear in the view pane but are not supported for printing. Transparency: Makes the Value box available. Values: Lets you enter a value or a range of values for grayscale channel transparency. Opacity: Makes the Opacity slide control available for changing the opacity of the grayscale layer. View 'No Data Value': When a grayscale layer contains 'no data' values, the View 'No Data Value' option is available. When you choose the View 'No Data Value' option, you can select a color from the color list for displaying them in the view pane. (See Display within Zoom Scale tab on page 49 ) Display within Zoom Scale tab The Display within Zoom Scale tab allows you to set independent zoom limits for your grayscale layer. When you zoom the view pane above the maximum scale or below the minimum scale, the grayscale layer is no longer visible. Minimum Scale: Lets you enter a minimum zoom scale. Maximum Scale: Lets you enter a maximum zoom scale. 49

52 Current Zoom Scale: Reports the current zoom scale for the RGB layer. Labels tab The Label tab on the Properties dialog box for the layer contains the label files associated with the project. For more information about labels see Managing the labels on page 356. About the PCT Layer Properties dialog box The PCT Layer Properties dialog box allows you to change general properties, switch source images and pseudo-color tables, adjust display properties, and set a zoom scale for the PCT layers. (See General tab on page 50 ) General tab Under the General tab, you can change generic information about your PCT layer and read other file information. Description: Lets you change the file name or description for the PCT layer appearing in the Maps tree. Read Only: Lets you change the Read/Write properties of the PCT layer. Visible: Makes the PCT layer visible in the view pane. Priority: Changes the priority of the PCT layer in your project or file. (See Changing the layer priority on page 28 ) (See Source Image tab on page 50 ) Source Image tab The Source Image tab allows you to select a new PCT image file and layer and a new pseudo-color table file and layer. PCTImage: Lets you select a new file, layer, and PCT. File: Allows you to choose a different file from a list of files you have open. Layer: 50

53 Lets you to choose a layer from the file you chose from the PCTImage file box. PCT: Lets you select a new pseudo-color table file and layer. File: Allows you to choose a different file from a list of files you have open. Layer: Lets you choose a new pseudo-color table from the file you chose In the PCT file box. (See Display tab on page 51 ) Display tab The Display tab has controls for changing the Opacity of the PCT image layer and for viewing #No data# values when they are included in a PCT image layer. Opacity: Makes the Opacity slide control available for changing the opacity of the PCT image layer. View 'No Data Value': When a PCT image layer contains 'no data' values, the View 'No Data Value' option is available. When you choose the View 'No Data Value' option, you can select a color from the color list for displaying them in the view pane. (See Display within Zoom Scale tab on page 51 ) Display within Zoom Scale tab The Display within Zoom Scale tab allows you to set independent zoom limits for your PCT layer. When you zoom the view pane above the maximum scale or below the minimum scale, your PCT layer is no longer visible in the view pane. Minimum Scale: Lets you enter a minimum zoom scale. Maximum Scale: Lets you enter a maximum zoom scale. Current Zoom Scale: Reports the current zoom scale for the RGB layer. Labels tab The Label tab on the Properties dialog box for the layer contains the Label files associated with the project. For more information about labels see Managing the labels on page

54 About the Bitmap Layer Properties dialog box The Bitmap Layer Properties dialog box allows you to change general properties, switch source files segment numbers and colors, adjust display properties, and set a zoom scale for your bitmap layers. (See General tab on page 52 ) General tab Under the General tab, you can change generic information and read other file information about a bitmap layer. Description: Lets you change the file name or description for the bitmap layer appearing in the Maps tree. Read Only: Lets you change the Read/Write properties of the bitmap layer. Visible: Makes the bitmap layer visible in the view pane. Priority: Changes the priority of the bitmap layer in your project or file. (See Changing the layer priority on page 28 ) (See Source Images tab on page 52 ) Source Images tab Under the Source Images tab you can change your bitmap layer source file and change your bitmap segment and colors. File: Lets you choose a file from the list of open files. Segment Number: Lets you choose from the list of bitmap segments available in your open files. Color: Lets you change the color of the bitmap segment. You can choose from the following color options: Red Blue Cyan Yellow White Black More The More option opens the Change Color dialog box, 52

55 which lets you create a custom color. (See Display tab on page 53 ) Display tab The Display tab has controls for changing the Opacity of the bitmap segment. Opacity: Makes the opacity slide control available. You can change the opacity of a bitmap segment when you want to see data from another layer through the bitmap in the view pane. (See Display within Zoom Scale tab on page 53 ) Display within Zoom Scale tab The Display within Zoom Scale tab allows you to set independent zoom limits for your bitmap segment. When you zoom the view pane above the maximum scale or below the minimum scale, your bitmap segment is no longer visible. Minimum Scale: Lets you enter a minimum zoom scale. Maximum Scale: Lets you enter a maximum zoom scale. Current Zoom Scale: Reports the current zoom scale for the bitmap segment. About the Vector Layer Properties dialog box The Vector Layer Properties dialog box allows you to change general properties, adjust display properties, set a zoom scale, and label vector layers. You can also add and remove metadata. (See General tab on page 53 ) General tab Under the General tab, you can change generic and display information and read other file information about a vector layer. Generic: Lets you change generic attributes of your vector layer. Description: Lets you change the layer file name or description of the vector layer shown in the Maps tree. Read Only: Makes the file read only. When you select this option you 53

56 cannot save changes to the vector layer. Visible: Makes the vector layer visible in the view pane. Selectable: Allows you to select a vector in the view pane using the selection tools. (See Display within Zoom Scale tab on page 54 ) Display within Zoom Scale tab The Display within Zoom Scale tab allows you to set independent zoom limits for your vector layer. When you zoom the view pane above the maximum scale or below the minimum scale, your vector layer is no longer visible. Minimum Scale: Lets you enter a minimum zoom scale. Maximum Scale: Lets you enter a maximum zoom scale. Current Zoom Scale: Reports the current zoom scale for the bitmap segment. (See Labels tab on page 54 ) Labels tab The Label tab on the Properties dialog box for the layer contains the label files associated with the project. For more information about labels see Managing the labels on page 356. About the Thematic Layer Properties dialog box The Thematic Layer Properties dialog box allows you to change general properties, adjust display properties, and set a zoom scale for the layers containing rasters with an RST. (See General tab on page 50 ) General tab Under the General tab, you can change generic information about your thematic layer and read other file information. Description: Lets you change the file name or description for the thematic layer appearing in the Maps tree. Read Only: Lets you change the Read/Write properties of the thematic layer. 54

57 Visible: Makes the thematic layer visible in the view pane. Selectable: Allows you to select a thematic in the view pane using the selection tools. Priority: Changes the priority of the thematic layer in your project or file. (See Changing the layer priority on page 28 ) (See Display tab on page 51 ) Display tab The Display tab has controls for changing the Opacity of the thematic image layer and for viewing #No data# values when they are included in a thematic image layer. Opacity: Makes the Opacity slide control available for changing the opacity of the thematic image layer. View 'No Data Value': When a thematic image layer contains 'no data' values, the View 'No Data Value' option is available. When you choose the View 'No Data Value' option, you can select a color from the color list for displaying them in the view pane. (See Display within Zoom Scale tab on page 51 ) Display within Zoom Scale tab The Display within Zoom Scale tab allows you to set independent zoom limits for your thematic layer. When you zoom the view pane above the maximum scale or below the minimum scale, your thematic layer is no longer visible in the view pane. Minimum Scale: Lets you enter a minimum zoom scale. Maximum Scale: Lets you enter a maximum zoom scale. Current Zoom Scale: Reports the current zoom scale for the thematic layer. Labels tab The Label tab on the Properties dialog box for the layer contains the Label files associated with the project. For more information about labels see Managing the labels on page 356. About the RST Properties dialog box 55

58 The RST Properties dialog box lets you change several aspect of an RST. General Tab Under the General tab, you can change the name of the RST file and change the current units of measure used by the RST. Description: Lets you change the name of the RST. Units: Reports the units of measure used by the RST. Modify: Opens the Modify dialog box. (See About the Modify dialog box on page 56 ) File Information The File information section shows the current path of the RST file and reports last date the file was modified. File Name: Reports the name and path of the RST. About the Modify dialog box From Ground To: Lets you choose a different unit of measure, select a standard scale from a list, or create a custom scale. Scale 1: Lets you enter a custom scale when you choose Custom from the From Ground To list. About the Symbol Properties dialog box The Symbol Properties dialog box lets you change the description of a symbol file and view the symbol file information. General Tab Under the General tab, you can change the name of the symbol file and view the file information. Description: Lets you change the description of the symbol file. File Information The File information section shows the current path of the symbol file and reports last date the file was modified. File Name: 56

59 Reports the name and path of the RST. Using the File Properties dialog box Characteristics of the data files that are saved to a hard disk are listed under the Files tab in the control pane. You can access the file information through a file Properties dialog box, which shows similar information for all file properties. The available information may differ depending on the file type you are viewing. You open a Properties dialog box for data items under the Files tree the same way as items under the Maps tree. (See Managing data properties on page 35 ) About the Bitmap Properties dialog box The bitmap Properties dialog box allows you to view and change several of the attributes for you bitmap files. You can review the file history, and add or remove metadata. (See General tab on page 57 ) General tab Description: Lets you change the file name or description appearing in the Files tree. Type: Reports the layer type. Size on Disk: Reports the size of the file on disk. Creation Date: Indicates when the layer was created. Last Update: Shows the last time the raster file was changed. Raster Size: Reports the size of the bitmap layer in pixels and lines. (See History tab on page 57 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 57 ) MetaData tab The MetaData tab provides a table for working with metadata names and values associated with the Raster file. 57

60 Name: Shows the name of the metadata file. Value: Lets you enter a new value for the metadata file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. About the File Properties dialog box The Files Properties dialog box allows you to review general file attributes, review the file processing history, manage file metadata, and view and change the file projection. (See General tab on page 58 ) General tab Description: Allows you to enter detailed information about a file. The description is shown in the Properties dialog box for the file. Type: Reports the file format. Size on disk: Reports the disk size of the file. Creation date: Indicates when the file was first created. Last updated: Shows when the last edit was made to the file. Raster Size: If applicable, reports the size of the raster in pixels and lines. Interleaving type: Reports the type of interleaving used in the file. The following interleave methods are reported: BAND interleaved: 58

61 Stores all data for one band together. Gives superior performance when bands are not accessed continuously. Not supported for files larger than 2 GB. PIXEL interleaved: Stores data for all bands at a particular pixel. May give better performance when all bands are accessed at the same time. FILE interleaved: Similar to BAND interleaved, but image channel data is stored in external files, one file per band. Tiled: Files have image data organized in many square sub images. Tiling provides faster access when a sub-area is extracted for file viewing, and supports compression formats. Pathname: Reports the full path and name of the file. (See History tab on page 59 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 59 ) MetaData tab The MetaData tab has a table that displays metadata associated with the file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. (See Projection tab on page 59 ) Projection tab The Projection tab allows you to view and change the projection of your files. Coordinate System: Allows you to select a coordinate system for a file. The available systems are: 59

62 Pixel UTM Long/Lat Meter Foot SPCS Other Earth Model: Opens the Earth Model dialog box, where you can choose from a list of datum and ellipsoids to define your coordinate system. More: Opens the UTM, State Plane Zones, or the Projection definition panel if you chose UTM, SPCS, or Other from the Coordinate System box. UTM panel: Lists the following choices depending on the type of coordinate system you chose: Table 3. UTM SPCS Other This Projection Opens this panel Zone and Row State Plane Zone Set the Projection Definition Bounds: Allows you to show the bounding coordinates of your file in either geocoded (Eastings and Northings) or geographic (latitude and longitude) units for UTM, SPCS, and other coordinate systems. Bounding coordinates are not shown for the Pixel option. Long/Lat displays the bounding coordinates in geographic units only. Meter and foot displays the bounding coordinates in geocoded units only. Upper left: The Upper Left boxes show the X, Y coordinates for the upper left corner of the file unless the file contains a rotated raster. If the file contains a rotated raster, the Upper Left boxes indicate the coordinates of the first pixel in the file, which is not necessarily the upper left corner. For more information, see About rotated rasters on page 34. Values are in the units of the selected coordinate system. Lower Right: The Lower Right boxes show the X, Y coordinates for the lower right corner of the file unless the file contains a rotated raster. If the file contains a rotated raster, the Lower Right boxes indicate the coordinates of the last pixel in the file, which is not necessarily the lower right corner. For more information, see About rotated rasters on page 34. Values are in the units of the selected coordinate system. 60

63 Rotation: The Rotation boxes indicate the amount the data is rotated. For more information, see About rotated rasters on page 34. Pixel Size X: Reports the horizontal pixel size in the units of the selected coordinate system. Pixel Size Y: Reports the vertical pixel size in the units of the selected coordinate system. About the Ground Control Points dialog box The Vector Properties dialog box allows you to view the properties and history of vector files. You can also change read/write attributes of the vector file, and add or remove metadata. (See General tab on page 61 ) General tab You can change information about your Ground Control Point (GCP) file and read other file information. Description: Lets you change the file name or description appearing in the Files tree. Type: Reports layer type. Size on disk: Reports the disk size of the layer. Creation date: Reports when the layer was created. Last updated: Reports the last time the GCP file was changed. Number of GCPs: Reports the number of GCPs in the layer. (See History tab on page 61 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 62 ) 61

64 MetaData tab The MetaData tab provides a table for working with metadata names and values associated with the pseudo-color table file. Name: The name column shows the name of the metadata file. Value: The value column lets you enter a new value for the metadata file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. About the Look-up Table Properties dialog box The Look-up Table Properties dialog box allows you to change several of the attributes for look-up table (LUT) files. You can review the file history, and add or remove metadata. (See General tab on page 62 ) General tab The General tab allows you to change generic information about your file and read other file information. Description: Lets you change the file name or description appearing in the Files tree. Type: Reports layer type. Size on disk: Reports the disk size of the layer. Creation date: Reports when the layer was created. Last updated: Reports the last time the LUT file was changed. (See History tab on page 63 ) 62

65 History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the table. (See MetaData tab on page 63 ) MetaData tab The MetaData tab provides a table for working with metadata names and values associated with the Look-up Table (LUT) file. Name: The name column shows the name of the metadata file. Value: The value column lets you enter a new value for the metadata file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. About the Orbit Properties dialog box The Orbit Properties dialog box allows you to change several orbit file attributes. You can change the name of the file, review the file history, and add or remove metadata. (See General tab on page 63 ) General tab Under the General tab, you can change the description of an orbit file layer and read other file information. Description: Lets you change the file name or description appearing in the Files tree. Type: Reports layer type. Size on Disk: Reports the size of the layer in bytes. Creation date: Reports the layer creation date. 63

66 Last updated: Reports the last date the file was changed. (See History tab on page 64 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 64 ) MetaData tab The MetaData tab provides a table for working with metadata names and values associated with an orbit file. Name: The name column shows the name of the metadata file. Value: The value column lets you enter a new value for the metadata file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. About the Pseudo-color table properties The Pseudo-color Table Properties dialog box allows you to change several of the attributes for you pseudo-color table files. You can review the file history, and add or remove metadata. (See General tab on page 64 ) General tab You can change information about your file and read other file information. Description: Lets you change the file name or description appearing in the Files tree. Type: Reports layer type. Size on disk: 64

67 Reports the disk size of the layer. Creation date: Reports when the layer was created. Last updated: Reports the last time the pseudo-color table file was changed. (See History tab on page 65 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 65 ) MetaData tab The MetaData tab provides a table for working with metadata names and values associated with the pseudo-color table file. Name: Shows the name of the metadata file. Value: Lets you enter a new value for the metadata file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. About the Raster Properties dialog box The Raster Properties dialog box allows you to change several of the attributes for your Raster files. You can give a raster file read-only status, review the file history, and add or remove metadata. (See General tab on page 65 ) General tab You can change generic information about your file and read other file information. Description: 65

68 Lets you change the file name or description appearing in the Files tree. Type: Reports layer type. Size on disk: Reports the size of the layer in bytes. Creation date: Reports when the layer was created. Last updated: Reports the last time the raster file was changed. Locking Status: Gives the raster layer read only status. Read-only Raster layers appear in the Files Tree with a red #X# next to the raster icon. Raster Size: Reports the size of the raster layer in pixels and lines. Data Type: Reports the bit depth of the of the raster layer as one of the following data types: 8-bit unsigned 16-bit signed 16-bit unsigned 32-bit real Overviews: Reports available overviews in the raster file. (See History tab on page 66 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 66 ) MetaData tab The MetaData tab provides a table for working with metadata names and values associated with the Raster file. Name: Shows the name of the metadata file. Value: Lets you enter a new value for the metadata file. Add: 66

69 Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. About the Signatures Properties dialog box The Signatures Properties dialog box allows you to change several of the attributes for the pseudo-color table files. You can review the file history, and add or remove metadata. (See General tab on page 67 ) General tab Under the General tab you can change information about your file and read other file information. Description: Lets you change the file name or description appearing in the Files tree. Type: Reports layer type. Size on disk: Reports the disk size of the layer. Creation date: Reports when the layer was created. Last updated: Reports the last time the Signatures file was changed. (See History tab on page 67 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 67 ) MetaData tab The MetaData tab provides a table for working with metadata names and values associated with the pseudo-color table file. Name: Shows the name of the metadata file. 67

70 Value: Lets you enter a new value for the metadata file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. About the Text Properties dialog box The Text Properties dialog box allows you to change several text file attributes. You can change the name of the file, review the file history, and add or remove metadata. (See General tab on page 68 ) General tab You can change the description of your file and read other file information. Description: Lets you change the file name or description appearing in the Files tree. Type: Reports layer type. Size on Disk: Reports the size of the layer in bytes. Creation date: Reports the layer creation date. Last updated: Reports the last date the file was changed. (See History tab on page 68 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 68 ) MetaData tab The MetaData tab provides a table for working with metadata names and values associated with a text file. 68

71 Name: Shows the name of the metadata file. Value: Lets you enter a new value for the metadata file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. About the Vector Properties dialog box The Vector Properties dialog box allows you to view the properties and history of vector files. You can also change read/write attributes of the vector file, and add or remove metadata. (See General tab on page 69 ) General tab Description: Lets you change the file description appearing in the Files tree. Name: Lets you change the name of the vector layer appearing in the Files tree. Type: Reports layer type. Size on disk: Reports the disk size of the layer. Creation date: Indicates when the vector file layer was created. Last updated: Shows the last time the vector file layer was changed. Data Type: Reports the type of vector data. Shape Count: Reports the number of shapes in the vector file layer. 69

72 (See History tab on page 70 ) History tab The History tab allows you to review the processing history of the data as a list of algorithms that have been applied to the data contained in the image channel. (See MetaData tab on page 70 ) MetaData tab The MetaData tab provides a table for working with metadata names and values associated with the vector file. Name: Shows the name of the metadata file. Value: Lets you enter a new value for the metadata file. Add: Lets you add records to the MetaData table. Delete: Lets you remove records from the MetaData table. Delete All: Lets you delete all of the MetaData records from the table. (See Projection tab on page 70 ) Projection tab The Projection tab allows you to change the vector projection and select an Earth model and a UTM zone for the vector layer. Projection: Allows you to choose a different projection for the vector file layer. You can choose the following projections from the list box: Pixel UTM - Opens the UTM Zones dialog box. Lat/Long - Makes the Earth Model button available and reports the current Datum and Ellipsoid. Meter - Makes the Earth Model button available and reports the current Datum and Ellipsoid. Foot - Makes the Earth Model button available and reports the current Datum and Ellipsoid. SPCS - Makes the Earth Model button available, reports the current Datum and Ellipsoid, and opens the State Plane Zones dialog box. Other - Makes the Earth Model button available, reports the current Datum and Ellipsoid, and opens the Other Projections dialog box. (See About the Other Projections dialog box on page 71 ). 70

73 Earth Model: Opens the Earth Model dialog box. More: Opens the State Plane dialog box. About the Other Projections dialog box The Other Projections dialog box lets you choose a projection other than Pixel, UTM, Lat/Long, Meter, Foot, and SPCS. The Other Projections dialog box is available when you choose Other from the projections list under the Projection tab in any Properties dialog box. (See Reprojecting files on page 134 ) Color mapping and image profiles Focus lets you map individual color elements and combinations of red, green, and blue (RGB) color elements to the channels in data with the RGB Mapping dialog box. You can also generate an image profile graph and a numeric table of profile values for your active images. The Profile Table and Profile Graph dialog boxes are used together when working with profiles and they allow you to print and save information. About the RGB Mapping dialog box The RGB Mapping dialog box shows the color content of red, green, and blue data in a multi-spectral data file table. The RGB Mapping dialog box lets you change or map the channel data to a color element and show the changes in the view pane. Target Map Layer: Reports the source file that contains the image layers listed in the RGB Mapping dialog box. Red: Lists the channels available for red mapping. Green: Lists the channels available for green mapping. Blue: Lists the channels available for blue mapping. Image Layers: Lists the data layers in the target Map layer that can be mapped to red, green, and blue color elements. 1. Select an image layer in the Maps tree. 2. From the Layer menu, click RGB Mapper. 3. Click in the Red, Green, and Blue columns next to the image channel to which you want to apply that filter. You can assign only one color to a channel. The image in the view pane changes according to the new mapping. 71

74 4. Click Close. Note: Changing band combinations cancels enhancements you have applied. To maintain an enhancement, you must enhance the image again. Remove an applied enhancement and then re-apply it. Creating an image profile Focus lets you generate a spectral plot and a table of numeric values across an overlaid vector that shows image information related to the RGB input channels. The resulting image profile gives a cross section of the pixel values under the vector. Focus automatically generates a table of pixel values for the vector. Pixel values in the profile table are across three image planes. You can save the table values as a text file and you can save and print the profile graph. Vector Profiles: If a vector is not open, a line is automatically generated and used to calculate the profile. You may want to create a vector profile under a specific area of your image or select an existing vector for the profile. You can modify the profile or draw a new one. To create an automatic image profile: 1. With a raster file open, do one of the following: Click Layer and then click Profile. Right-click a raster layer in the Maps tree and click Profile. Focus automatically adds a new vector layer to the Maps tree and a new vector to the view pane to calculate the vector profile. The Profile graph and table also appear. To create a new image profile: 1. With a raster file open, open a vector segment or add a new vector layer and draw a vector using the Vector Editing tools. 2. Select the image layer and click Layer and then click Profile. You can also right-click a raster layer in the Maps tree and click Profile. Focus automatically adds a new vector layer to the Maps tree and a new vector to the view pane to calculate the vector profile. The Profile graph and table also open. To display the image profile of the vector from the vector layer, select the vector layer in the Map tree. 3. Click the Vector Editing button. 4. Click the vector for which you want to make a profile. About the Profile Table dialog box The Profile Table dialog box lists the RGB values, X/Y positions, and scaled distances for each pixel included in the overlaid vector segment. Pixels are incremented automatically and several statistical and graphical 72

75 adjustments can be made. Sample: Reports an automatic increment for each pixel along the vector. Pixel 1 is the first pixel at the vector point of origin. Channel 1: Lists all of the pixel values for the color you have mapped to channel 1. Channel 2: Lists all of the pixel values for the color you have mapped to channel 2. Channel 3: Lists all of the pixel values for the color you have mapped to channel 3. Pixel/Line: Lists a pixel and line coordinate location for each pixel along the vector. X position: Lists the X coordinate for each pixel along the vector. Y position: Lists the Y coordinate for each pixel along the vector. Distance: Lists the scale distance for each pixel relative to the image scale. Distances are expressed in units of measure corresponding to the image in the view pane. Close: Closes the Profile Table dialog box. Graph: Brings the Profile Graph dialog box to the front of your desktop. Statistics: Opens the Profile Statistics dialog box. (See below) Save: Opens the Save Table dialog box. Options: Opens the Profile Options dialog box. (See About the Profile Options dialog box on page 74 ) About the Profile Statistics Dialog Box: The Profile Statistics dialog box is opened from the 73

76 Profile Table dialog box and shows the statistics for each channel in a selected layer. The following statistics are calculated automatically: Sample Min Sample Max Sample Avg Weighted Avg Statistics are a summary for the sample gray values along the profile. The weighted average is the most accurate measure of central tendency among the sample points. The weight of a sample gray value is the ratio of the length of a sample interval over the total distance of all the sample intervals. About the Profile Options dialog box The Profile options dialog box allows you to make changes to the profile graph and the profile table. You can simultaneously change information reported in the Profile Table and Profile Graph dialog boxes. You open the Profile Options dialog box with the Options button in the Profile Table dialog box. Color: Reports the colors used to plot the channels in the Profile Graph. Clicking in a Color column cell opens the Line Color dialog box. Visible: Reports the channels shown as plot lines in the Profile Graph and as channel columns in the Profile Table. Enabling a Visible column cell shows the corresponding line and column in the Profile Graph and the Profile Table dialog boxes. Current Channel: Lets you change the focus of the Profile Graph to the channel you want. Profile View: Lets you choose between a graph showing grayscale values along either a georeferenced or a sample point scale. Georeferenced: Switches the X axis of the graph to the linear scale view of your image. Sample Points: Switches the X axis of the graph to the pixel number view of the vector profile. 1. In the Profile Options dialog box, click a color chip for the corresponding channel. 2. In the Color Panel dialog box, make any changes to the basic color, color continuum, or intensity. 3. Click OK. About the Profile Graph dialog box 74

77 The Profile Graph dialog box lets you view the graph plotted from the information corresponding to the overlaid vector and the values listed in the Profile Table dialog box. You can zoom in the graph to look at a segment of the plot. Sample Profile of Selected Channels: Contains the graph with a profile of the channels you have chosen in the Visible column of the Profile Options dialog box. (See About the Profile Options dialog box on page 74 ) The vector profile is interpreted from left to right; however, if the end points of the vector occupy the same X position, the profile is interpreted from the top down. With closed shapes, the profile is interpreted in a clockwise direction from the start/end node. Gray-value changes are shown as a function of distance along the vector. The graph gives a profile of the image layer and the distance along the vector on the X axis. Gray Values: green, and blue input channels. Both 16-bit and 32-bit real raster data can be graphed showing the 16-bit and 32-bit range of values. Distance: When you choose the Georeferenced option in the Profile Options dialog box, the X axis is measured in meters and represents the distance between the end points of the vector. The range of the X axis depends on the length of the vector and the scale of the area or the ground distance covered by the image. Mensuration Bars: Reports the position of the measuration bars in pixels or in scale distance along the vector, depending on the Profile View option, selected in the Profile Options dialog box. You can move the measuration bars on the graph by dragging the left side of the graph to the right. Left Bar X: Shows the input channels plotted with the gray values along the Y axis of the graph. Sample Points: When you choose the Sample Points option in the Profile Options panel, an 8-bit RGB image layer shows a range along the X axis of 0 to 255 and represents the 256 possible gray-level values for each pixel of the red, Reports the X position of the left measuration bar. Left Bar Y: Reports the Y position of the left measuration bar. Right Bar X: Reports the X position of the right measuration bar. 75

78 Right Bar Y: Reports the Y position of the right measuration bar. Difference X: Reports the difference between the left and right measuration bars along the X axis of the graph. Difference Y: Reports the difference between the left and right measuration bars along the Y axis of the graph. Close: Closes the Profile Graph dialog box. Show All: Restores the graph to a full view after the graph has been zoomed. Graph Controls: Opens the Graph Controls dialog box. About the Graph Controls dialog box The Graph Controls dialog box allows you to change the viewable range for both the X and Y axes, export the plot to a graphic file, change the background color for the plot, and print the plot. X View Range: Allows you to set the minimum and maximum ranges of the X axis of the profile graph. Min: Allows you to enter a minimum range for the X axis of the profile graph. Max: Allows you to enter a maximum range for the X axis of the profile graph. Y View Range: Allows you to set the minimum and maximum ranges of the Y axis of the profile graph. Min: Allows you to enter a minimum range for the Y axis of the profile graph. Max: Allows you to enter a maximum range for the Y axis of the profile graph. Export: Allows you to choose a file and a format for exporting 76

79 your graph. File: Opens a File Selector dialog box, where you can choose a target file for exporting your graph. File Format: Lets you choose a file format for exporting your graph. Options: Lets you show a legend on your graph, lock the aspect ratio of the X and Y axes, and change the background color of the graph. Show Legend: Shows or hides the legend on the Profile Graph dialog box. The legend is printed with the graph when this option is checked. Fix Aspect Ratio: Locks the aspect ratio of the X and Y axes of the graph. Background: Lets you change the background color of the graph. Using the graph controls The Graph Controls allow you to edit the X and Y axis of a profile. You can also change the graph colors. You can control the range with the Min. and Max arrows. The Fix Aspect Ratio option holds the X and Y axis to the original relationship. The range varies depending on the ground distance covered by the image and the length of the vector. The range default value depends on the image bit depth (for example, 8-bit, 16-bit, and so on). At the bottom of the Profile Graph dialog box, click Graph Controls. You can also right-click in the profile and click Graph Controls. Range Controls: The range of the graph is controlled with the Min. and Max arrows. The Fix Aspect Ratio option holds the X and Y-axis to the original relationship. To adjust the X and Y axis independently, make sure this option is disabled. You can return to the original values by clicking Show All at the bottom of the Profile Graph dialog box. The range varies depending on the ground distance covered by the image and the length of the vector. You can also interactively draw a box on your vector profile graph to zoom into an area of interest on the graph by dragging a box around the area of the graph into which you want to zoom. You can zoom back out to the original X and Y range by clicking Show All. 77

80 Legend and Color Controls: You can show he legend for the color channels by enabling the Show Legend check box. Select a color from the Background list. Exporting profiles To export your profile information, you can: Save your graph as a PCIDSK (.pix), TIFF (.tif), bitmap (.bmp), or PostScript (.ps) file through the Graph Controls dialog box. Print the profile graph by clicking Print at the bottom of the Graph Controls dialog box. Save your profile table to a text file through the Profile Table dialog box. This text file can be imported to any spreadsheet for editing or analysis. You can change the file format before selecting the output file. 1. In the Export area of the Profile Graph dialog box, select a format from the Format list box. 2. Click File. 3. In the File Selector dialog box, navigate to and select a file. 4. Click Save. 5. In the Profile Graph dialog box, click Export. Printing your graph without showing the mensuration bars 1. From the Profile Table dialog box, click Options. 2. In the Profile Options dialog box, click the field with an X in the Current Channel column. 3. Click Close. 4. In the Profile Table dialog box, click Graph. 5. In the Profile Graph dialog box, click Graph Controls. 6. In the Graph Controls dialog box, click Print. 7. In the Print dialog box, click OK. Using the View tools Focus offers several tools to view, create, and save custom views of specific regions in your image data. This section covers the methods and tools for focusing on specific parts of an image. Using the Zoom window The Zoom Window lets you see a linked copy of your image data in a separate viewer. You can zoom the images independently, using one image to locate features and the other to zoom in for a closer look. You open the Zoom Window from the View menu. When you click the Lock command, you can move the cursor in the view pane without changing the image in the Zoom Window. Using a Clone view You can use the Clone View feature for several tasks. For example, if you want to compare classified images with reference images or if you want to analyse multi-temporal imagery, you can use Clone View to open several independently enhanced versions of the same 78

81 image to help discriminate certain features. The clone view command opens a second window for the current project. A copy of the project opens in the Maps and Files trees in the view pane. Clone views are independent of the source view showing in the original project window. Changes made to the project are not reflected in the cloned window. Once a Clone View is open, a new image can be opened in the project window with no effect on the cloned view. Chaining clone views When you have an open Clone View, you can use the Chained Window command to have the cursor position in the Focus view pane automatically control the cursor position in the Clone view, vice versa, or have both cursors affect each other. 1. From the View menu of the project window, click Clone View. 2. If you want the cursor in the Focus view pane to follow the cursor in the Clone view, click the Chained Window button on the Focus toolbar. 3. If you want the cursor in the Clone view to follow the cursor in the Focus view pane, click the Chained Window button on the Clone view toolbar. Zooming using the Overview window If you have a very large image file open or if your image is zoomed in, you can pan around the image in the view pane. There are two ways to pan around images: you can click the Pan button in the Focus toolbar or you can use the bounding outline in the overview window. The extents for the overview window are based on the extents of all data loaded in the main viewer regardless of what data types you set to be shown. When you open image data in Focus, the overview window shows a smaller version of the image in the view pane. The overview window has a bounding outline that you can use to control the view in the view pane. You can click the bounding outline to pan around the image in the view pane and you can resize the bounding outline to zoom the image in the view pane. 1. In the overview window, pointer to a corner of the bounding box. 2. Drag the bounding box to a new size. Dragging the box in the overview window moves the image in the view pane without changing the zoom level. Creating named regions You can create a custom view of your map or image with the Named Regions tool. When you create a named region, the viewer can move to it in the view pane. New named regions are defined by upper-left and lower-right corner coordinates. You can define the boundaries of a new region by using either the zoom tools on the Focus toolbar or by using the advanced features of the Named Regions dialog box. You can save 79

82 your named regions when you save the current project. If you add, remove, or edit the name of a Map or Area in the Maps tree, the information is updated in the Named Regions tree. The Named Regions dialog box has a tree similar to the one in the control pane. In the Named Regions tree, only the named regions are listed. New named regions are shown by either an Area-named regions icon or a Map-named regions icon. 1. In the Maps tree, choose an Area or a Map for defining your named region. 2. Use any of the zoom tools, including the bounding outline in the overview window, to define your region. 3. From the View menu, click Named Regions. 4. In the Named Regions dialog box, click the + button. 5. Type a name of the selected region in the Named Region 1 box. 6. Click OK. Removing named regions 1. From the View menu, click Named Regions. 2. In the Named Regions dialog box, select a region. 3. Click the - button. You can also right-click a named region in the Named Regions tree and click Remove. You can define a named region using coordinate information and you can edit your coordinates. By default, the advanced features show raster coordinates for the image data open in the view pane. You can describe the bounds of your named region in Raster, Geocoded, Geographic, or MGRS units. Creating named regions using coordinates 1. In the Named Regions dialog box, click Advanced. 2. Select a reference system from the Bounds list box. 3. Type the coordinates of your named region in the appropriate boxes, based on the selected reference system. 4. Click the + button. 5. Type a name of the selected region in the Named Region 1 box. 6. Click OK. Panning an image There are many ways to visualize image data in the view pane. This section covers all of the various methods and tools for looking at the parts of your image data that you want. Panning When you have a very large image file open or when your image is zoomed in, you can pan around the image in the view pane. There are two ways to pan around images: you can click the Pan tool in the Focus toolbar or you can use the bounding outline in the overview window. 80

83 1. On the Focus toolbar, click the Pan button. 2. Drag the image where you want to go. You can also scroll an image using the standard scroll bars along the horizontal and vertical edges of the view pane. Zooming You can zoom in or out to a particular location even when you have multiple images opened. Zooming an image with zoom tools 1. In the view pane, click a location or feature in the image. 2. On the Focus toolbar, click the Zoom In button. The image is enlarged by a factor of 2. To zoom out, click the Zoom Out button. Viewing a 1:1 image resolution 1. In the view pane, click the image. 2. On the Zoom toolbar, click the Zoom to 1:1 Image Resolution button. Note: When more than one image is open, the zoom tools apply to all images in the view pane. Using a layout grid The Layout Grid can use dots or lines to help you draw and lay out items in the view pane. You can align or position any map element relative to the grid. There are grid properties for Show Grid and Snap to Grid that can be turned on or off. You cannot print a Layout Grid. There are two options for displaying the grid: the first option shows the grid as dots; the second option shows the grid as lines. The index for the grid is displayed as a cross or wider line. All map objects can snap to the grid. For areas, the handles of the bounding box are used for snapping. The closest handle to the cursor click position snaps to a grid point. For Points, either text or symbols, the insertion point snaps to the grid point. For shapes, snapping is the same as snapping an area. A grid point is the intersection of a horizontal and a vertical grid line. When the grid is displayed as dots, each dot is placed at a grid line intersection point. Grid spacing The Grid Spacing section sets the spacing for both the dots and lines. Horizontal: The default spacing is 1.00 Millimetre 81

84 Vertical: The default spacing is 1.00 Millimetre. The unit options for spacing are in standard paper units: millimetre, inch, point, and pica. The Keep Equal option forces the grid spacing to be equal in both directions. You can disable the option if you want different horizontal and vertical spacing. This option is checked by default. Index spacing Index spacing is based on your grid spacing. Horizontal: Spacing for the index is in grid units. The default is 10. Every tenth dot or line is an index dot or line. Vertical: Spacing for the index grid is also in grid units. The default is 10. Every tenth dot or line is an index dot or line. The Keep Equal option forces the index spacing to be equal in both directions. You can disable this option if you want different horizontal and vertical spacing. Show Grid: Switches the grid off or on in the view pane. Enable this option to show the grid. Snap to Grid: Switches the grid snapping behavior off or on. Enable the check box to make map elements snap to the grid. 1. From the View menu, click Layout Grid Setup. 2. In the Layout Grid Setup dialog box, click either the Dots or the Lines option. 3. Select a color for your grid from the Color list. 4. Select grid and index spacing by entering values in the Grid Spacing and Index Spacing spin boxes. If you want to display the grid in the view pane, enable the Show grid check box. If you want new objects in the view pane to snap to your grid, enable the Snap to grid check box. 5. Click OK. Visualizing your data Focus provides a set of active visualization tools that can automate your work. The visualization tools are ideal for work requiring change detection between images recorded at different times. You can also use the visualization tools to ensure accuracy in your cartographic projects when you use imagery as a background layer to update vector or bitmap data. Enhancing images Images can be processed at several levels, from 82

85 standard enhancements that filter images to fully customized enhancements using look-up tables and histograms. Unenhanced image files are often impossible to understand visually when they are opened in an image viewer. Enhancements make imagery clearer and easier to interpret. When you open an image file, it is automatically enhanced in the view pane. You can change the default enhancement. (See Changing a default enhancement on page 244 ) Using the Attribute Manager The Attribute Manager produces a table showing all pixel values for raster attributes. You can select vectors, search for segments, and locate records. You can also edit vector attribute records and fields. (See Performing tasks in the Attribute Manager on page 304 ) From the Maps or Files tree, right-click a layer and click Attribute Manager. Importing XML metadata using the METAIN algorithm When you import data, you can also import image metadata from an XML-format text file and examine both global and band-specific metadata during the operation. Importing metadata is important when working with hyperspectral data. Many hyperspectral data sets include additional information about the mission and the sensor used to acquire the data. The first step in a project is to import data. If the data files are not in.pix format, you must obtain the data format. If the data is partitioned into different files, importing it in.pix format may require separate imports, transferring layers from one file into the final output file, or a single import. Mission and sensor metadata must be attached to the image data to make processing and analyzing it more efficient. The metadata must be formatted as an XML document in a text file. Metadata is read into the.pix file containing the image data as a metadata segment using the METAIN program. This can be opened through EASI or the Algorithm Librarian in Focus. Conversely, the METAOUT program will read the information in the metadata segment and export it as an XML document. The algorithm METAIN reads image metadata from an XML document that is stored in a text file, reformat the data, and stores them in a GDB file. The required format for an XML file can be found in the document PCIImageMetadata.xsd in the $PCIHOME\etc folder. The XML document file must be in the same folder and have the same base name as the GDB file. The XML document file must have an.xml file name extension. Global Metadata Many global metadata items are optional and can be absent from the data files you are working with. The following table is a list of both required and optional metadata items. 83

86 Table 4. Required Text data set descriptions Number of image bands Number and sequence of radiometric transformations stored as band-specific metadata. Band-specific Metadata Optional Name of the sensor model Name of the sensor type Location of image acquisition Time of image acquisition Heading of the platform Fore-aft sensor tilt relative to gravity vector Total sensor field-of-view Some band-specific metadata is also optional. The following table shows a list of both required and optional band-specific metadata items Table 5. Required Band-Specific Metadata Items Band ID number The number of the file channel that stores the band Optional Band-Specific Metadata Items Band quality Radiometric transformation sequence Required Band-Specific Metadata Items Optional Band-Specific Metadata Items Response profile The METAIN is in the Algorithm Librarian. The Algorithm Librarian lists algorithms in a tree of file folders. The folders are organized by algorithm category. Some category folders contain a sub-category of algorithms. 1. From the Tools menu, click Algorithm Librarian. 2. In the Select Algorithm dialog box, expand the Analysis folder. 3. Expand the Hyperspectral Analysis folder. 4. Double-click the METAIN algorithm. 5. In the METAIN Module Control Panel, click the Input Params 1 tab and click Browse. 6. Navigate to the file you want, select it, and click Open. 7. In the METAIN Module Control Panel, click Run. Opening an image data set 1. In the Files tree, right-click anywhere in the white area and click Add. 2. In the File Selector dialog box, locate and select a data file, and click Open. Viewing global metadata 1. In the Files tree, right-click the file you want to view and click Properties. 84

87 2. In the Properties dialog box, click the MetaData tab. The global metadata is listed. Viewing band-specific metadata 1. In the Files tree, expand the list of raster layers in your file. 2. Right-click a raster layer and click Properties. 3. In the Properties dialog box, click the MetaData tab. The band-specific Metadata is listed. Enabling and disabling panes The status bar contains several panes that communicate information from the viewer. Panes identified by a check mark are enabled. 1. On the status bar, click the down arrow on the left. 2. Select the pane of your choice: Messages: displays brief text messages to communicate ScreenTips, explanations, and instructions. Progress: displays a progress indicator that shows how much of a process is completed. ZoomScale: displays the scale at the zoom level used in the viewer. ZoomImagePixel: displays the magnification factor used in the viewer. CursorPosition: displays the coordinate of the cursor in the viewer. You can also select the unit for the coordinate#s display. SelectionValue: displays the pixel value at the cursor. Changing the units for the cursor position 1. On the status bar, click the down arrow on the CursorPosition bar. 2. Select the unit of your choice: Paper: displays the coordinates in millimeters. Raster: displays the coordinates in image pixels and lines measured from the upper left corner of the image. Geocoded: displays the coordinates in Easting and Northing values. Geographic: displays the coordinates in Longitude and Latitude values. MGRS: displays the coordinates using the Military Grid Reference System. Screen: displays the coordinates in screen pixels measured from the upper left corner of the viewer. Using the Visualization tools The visualization tools let you view and compare multiple image layers simultaneously. You can automatically browse a set of image layers or blend different images to see specific parts of one image through another. The tools can also be used with any of the enhancements or filters. Some visualization modes have different data requirements. For example, the Flicker, Blend, and Swipe 85

88 tools require files with more than one image layer to be visible. The Loop tool requires a minimum of three layers to be open and the Cycle tool requires either an RGB or a hyperspectral file. The following screens provide information for using each of the visualization modes that are available. (See About the Visualization Tools dialog box on page 86 ) About the Visualization Tools dialog box The Visualization Tools dialog box provides controls for the Flicker, Swipe, Blend, Loop, and Cycle tools. The controls for each visualization mode are separated by a tab at the top of the panel. You can set frame rates, image positions, mode orientation, and you can start and stop each visualization operation with the controls under the corresponding panel tab. For more information, see the following: Using the Flicker tool on page 86 Using the Swipe tool on page 86 Using the Blend tool on page 87 Using the Loop tool on page 88 Using the Cycle tool on page 89 Using the Band Cycling tool on page 90 Using the Flicker tool The Flicker tab controls the flicker visualization mode. Speed [frame/sec]: Allows you to change the frame rate of the flicker action. Actual: Reports the actual frame rate of the flicker when it is running. Control: Allows you to start and stop automatic flicker and to manually cycle through the flicker visualization mode. Current Top Layer: Reports the name of the active layer in the view pane. Using Flicker: Switches your view between two layers within the same Map. When you select any two layers in the Maps tree, the associated images flicker from the front to the back of the view pane, making it easier to see subtle differences between them. 1. From the View menu, click Visualization Tools. 2. In the Visualization Tools dialog box, click the Flicker tab. 3. In the Maps tree, select two layers by holding the Ctrl key while clicking the layers you want to view. 4. Type a value for the flicker rate in the Speed [frame/sec] box. 5. Click the Start Automatic Flicker button. Using the Swipe tool 86

89 The Swipe tab controls the swipe visualization mode. Horizontal: Changes the swipe to a horizontal direction. Vertical: Changes the swipe to a vertical direction. Position [%]: Allows you to step through a swipe cycle while reporting the portion of the cycle as a percentage of the swiped images. Auto Mode The Auto Mode area lets you set and operate the automatic swipe features. Speed [frame/second]: Sets the frame rate of the image swipe. Actual: Reports the actual frame rate for the swipe operation. Control: Allows you to start and stop the automatic image swiping. Step Size [%]: Lets you adjust the size of the swiped portion of the image in each step. Using Swipe: Displays a file in increments across another; at any point during the process, you can look at a specific percentage of the swiped file. 1. In the Visualization Tools dialog box, click the Swipe tab. 2. Click one of the following options: Horizontal: changes the swipe to a horizontal direction. Vertical: changes the swipe to a vertical direction. 3. Type a value for the size of the swipe percentage in the Position box. 4. Type a value for the flicker rate in the Speed [frame/sec] box. 5. Type a value for the step size in the Step size box. 6. Click the Start Automatic Swipe button. The swipe operation continues until you click the Stop Automatic swipe button. Using the Blend tool The Blend tab controls the blend visualization mode. Position [%]: 87

90 Allows you to step through a blend cycle while reporting the portion of the cycle as a percentage of the blended images. Auto Mode The Auto Mode area lets you set and operate the automatic blend features. Speed [frame/second]: Sets the frame rate of the image blend. Actual: Reports the actual frame rate for the blend operation. Control: Allows you to start and stop the automatic image blending. Step Size [%]: Lets you adjust the size of the blended portion of the image in each step. Using Blend: Merges two layers together at a specified rate. The transition from one view to another helps you see changes between layers. 1. In the Visualization Tools dialog box, click the Blend tab. 2. Type a value for the position of the blend in the Position box. 3. Type a value for the flicker rate in the Speed [frame/sec] box. 4. Type a value for the step size in the Step size box. 5. Click the Start Automatic Blend button. The blend operation continues until you click the Stop Automatic Blend button. Using the Loop tool The Loop tab controls the loop visualization mode. Forward: Cycles the data forward from the lowest to the highest priority. Backward: Cycles the data backward from the highest to the lowest priority. Continuous Loop: Cycles the data continuously according to the direction option you choose. Speed [frame/second]: Sets the frame rate of the image blend. 88

91 Actual: Reports the actual frame rate for the blend operation. Control: Allows you to start and stop the automatic image blending. Current Top Layer: Reports the name of the active layer in the view pane. Using Loop: Loop mode is a multi-view tool that extends automatic file comparison capabilities to include three or more files. You must have at least three layers open to enable the Loop tab. To use the Loop tool, click the Loop tab. Specify the desired flicker speed (frames/sec) and click the Start Automatic Loop button. You can specify a forward (starting with the first file and ending with the last file in the maps tree) or backward loop by clicking in the Forward or Backward options. If the Continuous Loop option is enabled the files will continually flicker. If the Continuous Loop option is disabled the files will loop only once. Using the Cycle tool The Cycle tab controls the cycle visualization mode. Color Channel The Color Channel section provides options for viewing channels and channel combinations you want to cycle. Red: Lets you cycle only the red channels in your data file. Green: Lets you cycle only the green channels in your data file. Blue: Lets you cycle only the blue channels in your data file. File: Reports the color channel source data file. Cycle Through All Files: Lets you cycle through all of the color channels in your image data. Channel: Changes the file report to show the channel currently being cycled. Display Ranges: 89

92 Lets you enter a range or series of channel ranges to be cycled in the view pane. Forward: Cycles your data forward from the lowest to the highest priority. Backward: Cycles your data backward from the highest to the lowest priority. Speed [frame/second]: Sets the frame rate of the image cycle. Actual: Reports the actual frame rate for the cycle operation Control: Allows you to start and stop the automatic image cycling. Current Top Layer: Reports the name of the active layer in the view pane. Using Cycle: Cycle mode displays image data through the color component you specify. The color that image channels cycle through is set using the red, green, or blue color channel options. You can select image channels to use with the Display Ranges text box.you can also specify whether the image layers will be cycled through the color component forward, starting with the first image channel you specify or backward, starting with the last image channel specified. (See Using the Band Cycling tool on page 90 ) Using the Band Cycling tool The cycle tool can be used with hyperspectral data to view different channel and wavelength ranges in a specified color component to create new color composites. You can cycle two color channels in the view pane and control the speed and range of channels that you are cycling through. 1. With image data open, click View and then click Visualization Tools. 2. In the Visualization Tools dialog box, click the Cycle tab. 3. Click a Color Channel option. The color you choose is the layer through which the hyperspectral channels cycle. 4. Enable a range of either channels or wavelengths to cycle using a selected color channel. To select a range of wavelengths, there must be associated metadata for each channel in the hyperspectral file. (See Importing XML metadata using the METAIN algorithm on page 83 ) 5. Enter a display range in the Display range box. 90

93 More than one channel or wavelength range can be entered. Ranges are shown using a dash between the beginning and end of the range; multiple ranges are separated by a comma. For example 1-5, 15-20, are valid entries for channel display ranges. 6. Select a cycle direction by enabling either the Forward or Backward option. If forward cycling is selected, the channel cycling order is 1-5, 15-20, and then 30-35; if reverse cycling is selected, the channel cycling order is 35-30, 20-15, and then Click the Start Automatic Cycle button. The cycling continues until you click Stop Automatic Cycle. The number at the bottom of the Visualization Tools dialog box represents the displayed channel. If you do not click Apply prior to clicking Close, the dialog box closes and the RGB layer reverts back to the original combination. Clicking Apply updates the RGB layer to reflect the new channel in the identified element and the layer name is updated. The following is a list of Band Cycling dialog box controls with details about what they do. Select Color Channel: Lets you specify the color of the view channel. The channels in the two colors that are not selected will not change. Next to the color is the file of the channel currently mapped to the color. If all the colors are mapped to a channel in the same file, these labels will not appear. Cycle through all files: Enable this check box when the active RGB layer contains channels from multiple files and you want to cycle through all the channels in all files mapped to the RGB layer. This function is only available when the colors of the active RGB layer are mapped to more than one file. Display Range: You can specify ranges of channels to cycle through a specified color component and you can specify either the channel number or wavelength. The system cycles through all available channels by default. Speed & Actual: Sets the channel cycle speed through the color element. The actual speed at which the channels are being cycled is also the speed they are displayed. Forward & Backward: Allows you to set the direction of cycling, either forward or backward. Control: 91

94 Stop and play buttons activate the cycling. You can also step through the channels one channel at a time. The direction of the stepping is set by the Forward and Backward options selections. Current Channel: The current channel being cycled through the identified color element is displayed. When you presses the stop button, the last channel cycled through is displayed. Opening the Thumbnails viewer You must have a file open before the Thumbnails viewer commands are available from both the Tools menu and the shortcut menu. A new map and area are added when you select layers from the Thumbnails viewer. The Thumbnails viewer works for multispectral and hyperspectral data, but displays raster layers only. If a file contains no channels, the Thumbnails command is not available. You can view images across several spectral bands in a tiled rectangular array. You can then display the images corresponding to several or all of the bands in the cube side by side. The Thumbnail viewer is available from the Maps tree and the Files tree. When you open the Thumbnail viewer from the Files tree, thumbnails of the full extents of the image are created for each channel. When you open the Thumbnail viewer from the Maps tree, thumbnails of a section of the image are created for each channel. The section used for the thumbnail is a 256-by-256 pixel area centered on the cursor in the image. In Black and White mode, you can click on an individual image from the tiled image array. Your image is then highlighted in white and displayed, full size, in the view pane as a black-and-white image. You can also work in RGB mode to select three images from the tiled image array, which are then outlined in red, green, or blue respectively. The corresponding composite RGB image is displayed, full size, in the Focus window. You then have the option of clamping and stretching the tiled image, or each of the RBG images individually to produce an optimal RGB image. With the Reload button you can limit the contents of the Thumbnails viewer to only the thumbnails that interest you. You can create thumbnails of a feature by magnifying the feature in the Focus view pane and then click Reload. Focus will recreate the thumbnails using the extents visible in the Focus view pane. You can set the options in the Thumbnails viewer and then click Reload. Focus will load the thumbnails according to the option that you set. For example, you can enter specific channels in the Display ranges box and when you click Reload only thumbnails of those channels will appear in the Thumbnails viewer. 1. Open a file that contains raster channels. 2. Click the layer in the Maps tree or in the Files tree. 3. From the View menu, click Thumbnails. About the Thumbnails viewer 92

95 The following is a list of the controls in the Thumbnails viewer: Display Range: Allows you to specify the channels to be viewed. The default is all channels. You can either specify the channel number or the wavelength. The wavelength is available only if the metadata contains band centers. Channel: Allows you to control the entries in the panel. If this is selected, then all of the entered values (display range, color components) correspond to channel numbers in the file. Wavelength: Allows you to control the entries in the panel. When selected, all of the entered values (display range, color components) correspond to wavelengths stored in the metadata segment in the file. When selected, the channel number has to be passed in order for the images to be displayed properly. Intensity Normalization: When selected, the LUT applied to each thumbnail is calculated using the histogram for that thumbnail (for example, the first thumbnail is channel 1 and the LUT applied to it will use the minimum and maximum from that channel. The second thumbnail is channel 2 and the LUT applied will use the minimum and maximum from channel 2, and so on). If the option is disabled, the minimum and maximum of the entire range of spectral bands in the file are used to apply the LUT. Grayscale: Allows you to display a single thumbnail. This thumbnail is highlighted by a white box. Only one thumbnail in the viewer can be highlighted at a time. The channel number of the selected thumbnail displays in the box next to the Grayscale option. When the option is enabled, the Red, Green, and Blue buttons are unavailable. RGB: Allows you to select three thumbnails to display in an RGB format. This works in the same manner as the Add Layer Wizard. If you enable the RGB option, the Red box is active and the first thumbnail selected is assigned to the red color component and is highlighted with a red box. The number of the channel is displayed in the box next to the Red button. The second thumbnail selected is assigned to the green color component and is highlighted with a green box. The third thumbnail selected is assigned to the blue color component and is highlighted with a blue box. If you want to change a thumbnail in one of the color components, you must click the color component and select a new thumbnail. OK: Adds the selected thumbnails to the Maps tree. If no Map or Area is present, the thumbnails are added to the Map tree list. If you have only selected one thumbnail, it is 93

96 displayed as a black-and-white layer. If you have selected three thumbnails, the layer displays as an RGB image layer. View: Allows you to view the selected thumbnails as full images in the view pane without closing the Thumbnails viewer. For each new selection, a new layer is added to the Maps tree. If no Map or Area is present, the thumbnails are added to the Map tree list. If you have selected one thumbnail, it is displayed as a black-and-white layer. If you have selected three thumbnails, the layer displays as an RGB image layer. Cancel: Closes the panel without saving. Help: Opens the Help for the panel. The Thumbnails tool bar has the following command buttons Zoom to Overview: allows you to zoom to the overview of the entire tiled image (all thumbnails). Zoom Interactive: lets you zoom into the tiled image. Zoom In and Zoom Out zooms in to and out of the tiled image. Thumbnail Overview: allows you to zoom to the overview of an individual tile within the tiled image. Pan: pans the tiled image. Select Channel: Selects a thumbnail for display. It is automatically active when you choose either the Grayscale or RGB option. 1. In the Thumbnails viewer, click Pick BW. 2. Click a thumbnail. 3. Click OK. Layer Selection When you have several layers in a file, you can quickly pick a single layer for input, output, or display with the Layer Selection tool. Using the Thumbnails viewer 1. In the Thumbnails viewer, type in the Display ranges box the band or channel numbers that you want to view to view. 94

97 2. Click Channel if the values in the Display ranges box represent channel numbers or click Wavelength if the values represent wavelengths stored in the metadata segment in the file. 3. Enable the Intensity Normalization check box to use the minimum and maximum values in the image to calculate a histogram and apply it to the thumbnail. When the Intensity Normalization check box is disabled, the histogram includes the entire range of values from all the channels. 4. Click Grayscale if you want to view the image as a grayscale layer and click the thumbnail that you want to view. 5. Click RGB if you want to view the image as an RGB layer. Click in order the thumbnails that you want to use for the red, green, and blue channels. The thumbnail is highlighted in the color of the corresponding channel and the channel number is displayed in the corresponding box. 6. Click View. Selecting grayscale and RGB layers To change the displayed raster layer in a map: 1. In the Thumbnail viewer, right-click a layer in the red, green, blue, or grayscale color component. 2. Click More. 3. In the Layer Selection dialog box, select a new layer and click OK. To select input or output layers: 1. Select More from the Input list box. 2. In the Layer Selection dialog box, type a layer number in the Layer number box. 3. Click Enter. 4. Click OK. You can also select output layers by following this procedure with the Output list box. The Layer List displays all of the channels in the file. When you click a layer, the layer is highlighted and the number of the layer is identified in the Layer Number box. The OK button accepts the layer as the new input. Visualizing data with the 3-D data cube The 3-D Data Cube is an independent graphical tool that displays a three-dimensional data model. You can work in the view pane while the 3-D display is active. You can work with any multi-layer data, including hyperspectral data. The 3-D Data Cube helps you to get a sense for the structure of the data you are working with by allowing you to assess the number and nature of spectra endmembers present in a scene. Hyperspectral data often achieves very large file sizes. You can see the spectral bands where there is high atmospheric absorption and thus very little signal reaching the sensor - black layers. In large files, to facilitate faster rendering, rotation, and excavation of the data cube, you must create a subset if 95

98 the data is not v-cube compressed data. You can use all data bit depths, but the 3-D Data Cube is optomized for 16-bit data. The 3-D Data Cube accepts compressed, decompressed, and raw hyperspectral files. Files must contain wavelength information. You can use the cube even if only one image channel has wavelength information. The 3-D Data Cube can display, rotate, and excavate three-dimensional data. The tool displays the cube in an arbitrary orientation, with a rectangular cutout, using parallel projection. 1. Select an image file in the Maps tree. You can use B&W, multispectral, and hyperspectral data. 2. From the View menu, click 3-D Data Cube. By default, enhancements applied to data layers in the view pane are applied the top layer in the 3-D Data Cube. About the 3-D data cube controls The 3-D Data Cube viewer has a menu bar and toolbar that are independent of the view pane. The viewer also includes controls that let you zoom, rotate, and excavate the cube image. 3-D Cube Menu Bar The 3-D Cube menu bar lets you control several aspects of the 3-D viewer and the data you are viewing. File: The File menu lets you import image files, load PCT layers, and exit the 3-D Data Cube. Import Image: Opens the Import Image dialog box. Load PCT: Opens the Select PCT Layer dialog box. (See About the Select PCT Layer dialog box on page 98 ) Exit: Closes the 3-D Data Cube. Edit: Lets you edit a PCT and change the background color of the 3-D viewer. Edit PCT: Opens the PCT Editing dialog box. (See Adjusting the pseudo-color for single values on page 241 ) Background Color: Opens the Change Color dialog box. View: 96

99 Lets you show or hide the image layer and the cube sides, and allows you to zoom the image in the viewer. Image Layer: Shows or hides the image portion of the data cube. Cube Sides: Shows or hides the cube sides portion of the data cube excavation. Zoom To: Opens the Zoom sub-menu. 3-D Data Cube Toolbar The 3-D Data Cube toolbar lets you save files, edit pseudo-color tables, zoom and pan your image, and enable the cube rotation. Save: Opens the Export Image dialog box, which lets you save the file you are viewing to a new location. Pseudo-color Table: Opens the PCT Editing dialog box. (See Adjusting the pseudo-color for single values on page 241 ) Overview: Displays an overview of the 3-D image. Zoom Window: Lets you zoom the image by clicking in the 3-D image in the 3-D window. Zoom In: Makes the 3-D image larger. Zoom Out: Makes the 3-D image smaller. Zoom 1:1: Shows the 3-D image at 1:1 scale ratio. Pan: Lets you pan the 3-D image within the 3-D window. Rotate: Lets you rotate the 3-D image along the X, Y, and Z axis. Cube Excavation The Cube Excavation Area has text and slide controls that let you view a rectangular section of the layers in the cube. You can change the shape and the depth of the excavation using the slide controls. When you use a 97

100 wheel mouse, you can lock the excavation of the X, Y, or Z plains of the cube. You can also lock all three at once and change the view of the excavation with your wheel mouse. X: Changes the horizontal axis of the cube excavation. The X option box lets you lock the horizontal axis excavation when you use a wheel mouse. Y: Changes the vertical axis of the cube excavation. The Y option box lets you lock the vertical axis excavation when you use a wheel mouse. Z: Changes the depth of the cube excavation. The Z option box lets you lock the depth excavation when you use a wheel mouse. Flip Controls The Flip controls change the orientation of the excavation. Flip X: Flips the X axis from right to left. Flip Y: Flips the Y axis from right to left. Flip Z: Flips the Z axis from top to bottom. Using the Excavation Controls: You can control height, width, and depth of the excavated portion of the cube. When you use the slide control, the image and the number above the slide control are automatically updated. The minimum for each box is 1; the maximum number is the number of layers in the data set. The maximum for the X axis is the maximum number of pixels displayed in the Focus view pane. The maximum for Y is the maximum number of lines displayed in the Focus view pane, and the maximum for Z corresponds to the number of image channels in the file. If the image is at Zoom to Overview, the maximum X and Y are the extents of the image. Each single-digit increment removes one pixel, line, or channel from the display. The excavation is determined and applied by default when the cube is opened. The starting point of the excavation is the lower-right corner, X max and Y max, and the top most image layer Z min. You can flip the excavated area a full 180-degrees in the X, Y, or Z dimensions using the Flip buttons. About the Select PCT Layer dialog box The Select PCT Layer dialog box lets you choose an alternative pseudo-color table (PCT) for the data 98

101 displayed in the 3-D Data Cube viewer. Input: Provides a way to locate and apply a different PCT layer. File: Lets you choose a file where the PCT layer is located. Browse: Opens a File Selector dialog box to locate files not listed in the file box. Layer: Lets you choose a PCT layer from the file selected in the File box. Selecting colors There are several cases where you need to create custom colors. For example, you can choose custom colors for vectors, points, polygon fills, training areas, and more. In each case a color selection panel is available for creating custom color. The color panel may differ, depending on the task you are performing. Custom colors are created using a combination of three basic color palettes. Color palettes Basic Colors: This is a palette of 49 basic colors that are preset and cannot be modified. Color Continuum: This is the palette of infinite colors in the middle of the dialog box. This palette is made up of all the possible hue/saturation combination of values. Lightness/Intensity Scale: This palette controls the brightness of the color you create. When you choose the Gray color model, the Lightness/Intensity Scale is the only available palette. The color you create using the palettes is displayed alongside the color that is being replaced. The numeric representation of the new color appears in a series of data entry fields. You can edit the entries in these fields and the new color changes accordingly. The number of fields present corresponds to the chosen color model. Color models RGB: This is one of the Additive Color models and is based on light emitted from a source, such as a computer monitor. It has three primary colors: red, green, and blue. All the colors on a screen are produced by combining these three colors in various proportions. 99

102 CMYK: This is one of the Subtractive Color models and is based on light being absorbed and reflected by paint and ink. This model is often used when printing. The primary colors are cyan, magenta, yellow, and key (black). HLS/IHS: This is a more intuitive model based on the way we perceive color. The primary components are hue, lightness or intensity, and saturation. Gray: This is a continuum of gray values. The gray scale ranges from pure black to pure white. To select a basic color value 1. In the Basic Colors palette, click a tile. The Red, Green, and Blue values change to match the selected color. In addition, the color appears in the New box and the slider control changes position to show the value for the lightness and intensity of the new color. To obtain a more precise color in terms of shade and strength 1. In the Color Continuum, click a value. To control the brightness of the color 1. Click the slide control and move the arrow up or down to increase or decrease the lightness and intensity of the color. To control color values at the pixel level in the RGB model 1. Click the arrows for the Red component. This increases or decreases the numeric value of the red pixels. 2. Click the arrows for the Green component. This increases or decreases the numeric value of the green pixels. 3. Click the arrows for the Blue component. This increases or decreases the numeric value of the blue pixels. To change the color model 1. Click the Model arrow and choose one of the following: RGB: changes to a red, green, and blue color model CMYK: changes to a cyan, magenta, yellow, and black color model HLS/IHS: changes to a 3-D color model Gray: changes to a grayscale model 100

103 2. Click OK. Setting options and preferences You can customize how Focus handles certain features and how it uses your system resources with the Options dialog box opened from the Tools menu. The Options dialog box is divided into two parts. On the left is a list of options. When you select an option, the right side of the dialog box changes to give you access to the preferences for that option. The Options dialog box lets you customize the following features: Table 6. Option Layer Manager OpenGL settings Setting shape and color preferences Setting up a digitizing tablet using Wintab Setting up a GPS receiver Measurement tools Controls Visible column options 3-D Data Cube preferences View pane selection preferences Tablet setup Receiver setup Units and report preferences Option General interface Warnings Layers Default representation Vector editing Memory cache Overview window Zoom window Controls Cursor and menu preferences Interface warning preferences Zoom and raster preferences Default data-type representations Vector editing tolerances Undo, tiling, total, and vector caching Rasters, vectors, and colors X and Y sizes, tools, and status bars General interface The General interface option includes a Warnings preferences sub-category. General interface options include: Render white tiles Delays the rendering of the image when you pan until you release the pointer. When Render white tiles is enabled, previously unviewed sections of the image appear white as you pan until you release the mouse button. When Render white tiles is disabled, you can pan with continuous rendering of the image, which can result in decrease in performance depending on the size of the image. Reload previous project on startup 101

104 Reloads the previous project on start-up. Show Shows and hides tabs, message bars, the overview window, the legend in the Maps tab, and ToolTips. Cursor Customizes the shape, size, and color of the cursor. You can choose from none, cross, empty cross, target, bracket target, and dot cursors. Warnings The Warnings option allows you to disable common warning messages. By default, all warning messages are enabled. To deactivate a particular warning message, disable the check box next to it. You can choose from the following Warning messages: Attempting to view data with METER projection: This message appears each time you open a layer if Focus which has METER projection assigned. Some file formats do not save projection information but do have bounding coordinates. Such layers are assigned a METER projection by default. This warning message can be useful for remembering to assign the appropriate projection to the data. Attempting to view data that has to be reprojected: This message appears when you try to add data to a project that is not the same projection as the active map. When you do this the new data is reprojected to the active Map projection. This warning message can remind you that the project has not been saved in the same projection. Creating a new area in order to view data that can#t be reprojected: This warning message appears when data that cannot be reprojected is added to an active Map that already has an assigned projection. Data that cannot be reprojected includes layers or files that have METER or PIXEL georeferencing assigned to them. In this case, a New Area is created for the layer. Modifying a layer's representation if it may affect other layers: This warning message appears when a representation that is linked to more than one layer is edited. By editing the representation style of one layer that is linked to an RST, the representation style of another layer that is also linked to the same RST may be changed if the same REPCODE is used by both layers. This warning message can let you know that the representation changes being made to one layer may also affect another layer. Required input is missing in the Layer Manager: This warning message appears when information for a 102

105 particular Layer Manager operation is missing and the system cannot carry out the operation you have requested. Fully within spatial operator not available for thematic rasters: This warning message appears as a reminder that you are attempting to use the Fully Within tool on a thematic raster. Layers The Layers option allows you to specify various preferences for opening and displaying layers in Focus. For example, you can change the zoom level when adding a new layer to a project. This is controlled by the When Loading menu. The following zoom levels are available: Zoom to Overview Displays an overview of the map each time a new layer is opened. Zoom to Full Extents of Layer Displays the full extents of the newly opened layer. Don't Change the Zoom The current zoom level is maintained when a new layer is opened. When a new raster layer is opened, you can have a 1:1 zoom level applied by default. This is specified by enabling the Load Rasters at 1:1 resolution check box. If you open several rasters at the same time, the default enhancement may be unsatisfactory for all rasters. If you intend to regularly open several rasters at the same time, it may be advisable to clear the Load Rasters at 1:1 resolution check box. There are two menus in the Rasters area that specify the display properties of rasters when they are opened into Focus: the Default resampling method and Default visual enhancement. The Default resampling method specifies how the raster will be resampled for viewing when at greater than 1:1 resolution. The resampling options are Nearest neighbour, Bilinear interpolation, and Cubic convolution. The Default visual enhancement menu specifies the default visual enhancement that will be applied to a newly opened raster. The default visual enhancements offered are None, Linear, Root, Adaptive, Equalization, and Infrequency. The Default overview area contains a menu that allows you to specify the preferred overview generation method. The overview generation methods offered are Nearest neighbour, Block average and Block mode. Default representation The Default representation option consists of a Data Type area and a Preview pane. You can change the 103

106 default point, line, and polygon representations for vector layers. When you open a vector layer, the default representation set in the Options dialog box is applied to the layer. This default remains a property of the layer while the layer is open. Changing the default representation in the Options dialog box does not affect the vector layers that are currently opened in the viewer. Changes to the settings in the Options dialog box affect only those layers that are subsequently opened. Changes to the default representation for vector layers currently open in the viewer are made in the Default representation area of the Vector Layer Properties dialog box. You can also change the default point, line, and polygon representations for your vector layers, just like the Data Type area. The changes are applicable to the current session only. When you open the layers in a new session, the default representation set up in the Vector Layer Properties dialog box is lost and replaced with the settings in the Options dialog box. To make your settings permanent, set the default representation in the Options dialog box; also, set up the default representation before you open any vector layers. Vector editing The controls in this option are used for creating and editing vectors. The Vector editing option sets the units and tolerances for Search, Snap, and Weed vertices tolerances in either pixels, meters, or feet. By default, the tolerances are measured in pixels. This option also sets the snap feature for digitizing operations. Snap Tolerance: The snap operation is only used on a line or at the start of an area edit function. When the choice is to snap a line or area start to a vertex or a line, the snap tolerance is used to limit the lines or vertices that are available to snap to, given the cursor's current position. Snap Automatically: Is only used in a line or at the start of an area edit function. The snap default dictates whether a line or an area is started or ended with a snap when you want to start or end the line, or begin the area while still within the distance specified by the Snap Tolerance. Search Tolerance: Limits the cursor search for a vector feature to select. Weed Vertices Tolerance: Is used when digitizing line and area data. The value of the weed vertices tolerance specifies the minimum distance between the last vertex digitized and the current pointer position within which another vertex can be digitized. 104

107 To set the snap tolerance 1. Type a value in the Snap tolerance box. 2. Choose a measurement unit from the Snap tolerance list box. The default unit is pixels. To activate the snap operation 1. Enable the Snap check box. When digitizing, you can still activate or deactivate the snap operation by holding the Alt key while starting or ending a line or starting an area. To set the tolerance for a vector search 1. Type a value in the Search tolerance box. 2. Choose a measurement unit from the Search tolerance list box. The the default unit is pixels. Clicking the cursor within this tolerance of a feature selects it. Clicking within this tolerance of a vertex or node that is on a previously selected line highlights the vertex or node. To set the tolerance for weed vertices 1. Type a value in the Weed vertices tolerance box. 2. Choose a measurement unit from the Weed vertices tolerance list box. The default unit is pixels. Memory cache The Memory cache preferences let you configure system memory for various memory cache options. You can adjust for Undo/Redo, Tiling, Total limit, and Vector read cache. The memory cache panel provides a way to limit system memory usage for the current application. The total limit is the maximum amount of memory caching available on your system. Undo/Redo: The Undo/Redo box lets you specify, in kilobytes (1024 KB = 1 MB), the amount of memory up to 25 MBs available for undo and redo steps. (See Optimizing the Undo/Redo options on page 106 ) Clear Undo/Redo cache: Clears all cached undo and redo operations from your system. Tiling: Lets you specify, in kilobytes, the amount of memory available for raw image inputs and display caching output. (See Optimizing the tiling cache on page 106 ) 105

108 Clear tiling cache: Clears all cached tiling operations from your system cache. Total limit: Lets you specify, in kilobytes, the limit of memory allocation. When zero is entered, the system uses all of the available system memory as the memory cache limit. (See Setting the total cache limit on page 107 ) Default memory usage: Re-sets the total limit of cache to the default level. The default memory usage is one-half of the system memory. For example, if a system has total memory of 500 MB, the default memory usage command sets the cache to 250 MB. Vector read cache: Lets you enter a value for the number of lines, polygons, and points that can be cached by the system. The vector read cache is independent of values set in the Total limit box. (See Setting the vector read cache on page 107 ) Default read cache: Re-sets the default number to 4,000 cached shapes. Optimizing the Undo/Redo options You can control how much memory Focus allocates to undo and redo operations. For example, when you are burning a shape within a raster image, the old state of the application is kept in memory. The size of the bounding box of the new shape, in pixels and lines for raster data types, and the number of input channels are all stored temporarily as an undo/redo step. This can use a lot of system memory. The number of undo steps cannot be computed based on the size of the undo/redo cache. Each undo step requires varying amounts of memory. The Undo/Redo box lets you enter a value in kilobytes. This setting is affected by the total limit setting which is composed of both undo/redo and tiling settings. Adjusting the undo/redo setting lets you make sure that the total limit is divided, based on the way you work, between undo/redo and tiling. Optimizing the tiling cache The larger the data set, the more memory a system needs to function effectively. For example, an 8-bit image measuring 512 pixels x 512 lines requires 1 byte for each pixel, or 1 MB of information for each 8-bit raster layer. With very large files, you can experience memory deficits requiring more memory to display requested data. If the tiling cache is set too low, a system will swap data because it is designed to de-allocate and then re-allocate memory to stay within the limits of your data. The tiling cache changes the way you can render an image in the view pane. When you work with very large images, you can increase the memory allocated to tiling, which has a direct impact on rendering. By increasing the 106

109 size of the tiling cache, you increase the speed of image rendering. Setting the total cache limit The total cache limit is the sum of the undo/redo and the tiling cache. If both are set to zero, the limit becomes the total limit for the sum of the two. You can specify, in kilobytes (1024 KB = 1 MB), the limit of memory allocation. When zero is entered, the system allocates 1/3 of the RAM installed on the system as the total limit of memory cache. Setting the vector read cache The vector read cache increases performance with very large data sets. This is a GDB vector cache and is independent of the value set in the Total limit box. When you increase the vector-read cache value, the system does not need to access the data from the shapes saved in the data files on your hard disk. The result is an improvement in overall system performance. Overview window The Overview window option allows you to set the display properties of the overview window. For more information on the overview window, see Zooming using the Overview window on page 79. In the Show area there are check boxes for both Raster and Vector. These control which type of data will be displayed in the overview window. A check mark indicates that the data type will be shown in the overview window. The View box color list box controls the color of the view box in the overview window. The View box color list box contains a color palette with 49 available colors. Additional colors are available by clicking More. Zoom window The Zoom Window option allows you to set the display properties of the zoom window. The default size of the zoom window that is launched is controlled by the Default X-size and Default Y-size spin boxes. These sizes can be adjusted by using the arrow keys in the Default X-size and Default Y-size spin boxes. Alternatively, you can type a desired default size directly into the boxes. If the Keep equal check box is enabled, the value of the X-size and Y-size of the zoom window will be the same. The Icon toolbar check box controls the Icon toolbar in the zoom window. If enabled, the Icon toolbar displays at the top of the zoom window. The Show status bar check box controls the status bar in the zoom window. If enabled, the status bar displays at the bottom of the zoom window. Layer Manager 107

110 The Layer Manager option allows you to specify the fields appearing in the Layer Manager. By default, all of the columns in the Layer Manager display. You can remove fields in the Layer Manager display by disabling the appropriate check box. (See Using the Layer Manager on page 31 ) Open GL settings The Open GL settings has preferences for setting the maximum texture size of the 3-D Data Cube. The system can determine the maximum texture size or you can set the maximum texture size manually. Setting shape and color preferences The selection preference option lets you change the default condition of selected points, lines, polygons, text, and rasters. To set selection options, click the + next to the Selection option. When you choose Selection in the option list, there are two initial options. Consider interior of polygon: Lets you select a polygon by clicking inside the polygon boundaries, even if it is not a closed figure. Select only if fully contained: Lets you select a polygon by clicking inside the polygon boundaries only if the polygon is a closed figure. Points: Allows you to change how selected points associated with a layer appear. The color option allows you to change the highlight color of selected points. The Width option is used to specify the width of the outline that appears around the points. The default value is With several points selected, choose a color from the Color palette. 2. Enter a value that represents the width of the outline that appears around the points from the Width spin box. 3. Click Apply. Lines: Allows you to change the color and width of a selected line associated with a layer. The Width option is used to specify the width of the line used to highlight one or more selected lines. The default value of the highlight width is 1. Modifying a selected line 1. Choose a color from the Color palette. To select a color other than those displayed in the color blocks, click More and create a new color. 2. Enter a value that represents the width of a line in the Width spin box. 3. Click Apply. 108

111 Polygons: Allows you to change the outline and fill of a selected polygon. Opacity refers to the degree of opaqueness. A value of 100%, means that you cannot see another object through the fill color. An opacity value of 0% means you can see through the fill color completely. Modifying a selected polygon 1. In the Outline area, choose a color from the Color palette. To select a color other than those displayed in the color blocks, click More and create a new color. 2. Enter a value that represents the width of the polygon outline in the Width spin box. 3. In the Fill area, choose a color from the Color palette. To select a color other than those displayed in the color blocks, click More and create a new color. 4. Enter a value that represents the percentage of the fill opacity in the Opacity spin box. 5. Click Apply. Texts: There are three Texts preference options. The Color option allows you to the change the insertion point and highlighted text color. The Highlight insertion point option allows you to see where text associated with a layer is inserted. The Highlight text option allows you to highlight the selected text. Applying preferences to selected text 1. Choose a color from the Color palette. To select a color other than those displayed in the color blocks, click More and create a new color. If you want to highlight the text insertion point, enable the Highlight insertion point check box. If you want to highlight the selected text, enable the Highlight text check box. 2. Click Apply. Changing the style for hatches You can change the style, color, and size of raster hatches. Choose a hatches style from the Hatches palette. To select a style other than those displayed in the hatches blocks, click More and choose a new symbol. 109

112 Changing the raster color Choose a color from the Color palette. To select a color other than those displayed in the color blocks, click More and create a new color. Changing the raster size Enter a value that represents the raster size in the Size spin box. Setting up a digitizing tablet using Wintab You can connect a digitizing tablet to your system and use it with Focus. The Digitizing Tablet option lets you set up a digitizing tablet. Before using a digitizing tablet, you must connect it to the computer and set up the software to communicate with the tablet. Focus supports Wintab and provides several other tablet drivers. 1. Ensure the digitizing tablet is connected according to the manufacturer instructions. 2. From the Tools menu, click Options. 3. Select Digitizing Tablet. 4. Enable the Wintab device option. If your device is Wintab enabled, The Wintab device option is enabled by default, and the Device setup area is populated with the Wintab settings. 5. Enter the values of components by reading them from Wintab. 6. Click Test Connection. The Digitizing Tablet Connection Testing dialog box opens. See Testing the digitizing tablet connection on page 111 Setting up a digitizing tablet using a driver 1. Ensure the digitizing tablet hardware is connected according to the manufacturer instructions. 2. From the Tools menu, click Options. 3. Select Digitizing Tablet. By default, the Generic device option is selected, and the Wintab device option is unavailable. The Device setup area is populated with default settings. 4. Choose a hardware communication port from the Device list box. 5. Choose a driver that matches your device from the Tablet list box. Note that the SummaSketch III digitizer is no longer supported, however, the ASCII BCD report format is supported. 6. In the Communication settings area, choose a baud-rate, data-bit, parity, and stop-bit value from the appropriate list boxes, according to the digitizing 110

113 tablet manufacturer specifications. 7. Click Test Connection. See Testing the digitizing tablet connection on page 111 The setup is successful if a device string appears in the Device String box in the Digitizing Tablet Connection Testing dialog box. If no device string displays, click OK to reset the device setup and communication settings. Testing the digitizing tablet connection The Digitizing Tablet Connection Testing dialog box shows information to help you determine if the computer is properly communicating with the tablet and to help PCI Support diagnose digitizer problems. When the dialog box is opened, all of the boxes are blank. When you click the digitizer puck, these boxes are populated with device string information. The device string is not visible when using Wintab. Assigning text actions and modifiers When you have successfully connected the digitizing tablet, you can assign actions to the puck buttons on your digitizer. In the Puck button assignment area, the first four buttons have the following default assignments: Table 7. Button Action Modifier 1 Mouse Click None 2 Enter None 3 Escape None 4 Delete None 1. Enter a puck button number in the Button spin box. If an action is already associated with this button, you can update both the Action and the Modifier list boxes. The Action and Modifier list boxes are set to None when neither an action nor a modifier are associated with a button number. 2. Choose an action from the Action list box. 3. Choose a modifier from the Modifier list box. 4. Click Apply. Setting up a GPS receiver The GPS receiver option lets you set up a GPS receiver to use with Focus. You can set up the serial port connections and parameters to connect a compatible GPS receiver. Only GPS receivers that support the NMEA protocol are supported. Most GPS receivers support this protocol, which allows devices from different vendors to communicate over a serial connection in a marine setting. NMEA is used across the GPS industry. The supported formats in the setup panel are based on common data output formats. For example, the NMEA-0183 (ASCII) format. Focus reads only the X, Y, and Z coordinates from the NMEA format. Coordinates supplied by the NMEA format are latitude and longitude, using a WGS84 ellipse. Before setting up a GPS receiver, make sure a GPS 111

114 device is connected to a serial port on your computer. Device settings: The GPS receiver options are specifically related to setting up the GPS that you are using. The Device box specifies the port where you have attached your GPS. By default, this option is set to COM1. See the information provided with your GPS unit about which port to use. 1. Enter the connection port that will be used in the Device box. 2. Choose a baud rate, data bit, parity, and stop bit from the appropriate list boxes in the Communication settings area. You can change values back to the default values by clicking Restore defaults. 3. Enter a value that represents how frequently the points should be captured from the GPS, from four to 300 seconds, in the Capture every spin box. 4. Click Test connection. The GPS connection is automatically tested in the GPS Connection Testing dialog box. Testing the GPS connection The GPS Connection Testing dialog box opens when you click Test connection. You can determine if the connection to your GPS has been made correctly. The connection is tested automatically each time you click the Test Connection command button in the GPS receiver pane. You can also manually test the connection by clicking the Try Again button at the bottom of the GPS Connection Testing pane. If the GPS connection is successful, the Device String box displays the current geographic coordinates from the receiver. The Location area shows the elevation as long as the GPS can display elevation. If the GPS connection is unsuccessful, an error message is generated. If an incorrect device (for example, a digitizing table) has been connected, the panel will show a device string. The location information will not be displayed. If you want to manually re-test the connection, click Try Again. Measurement tools You can set the behaviour of the Measurement tools in the view pane. Linear, Area, and Angle options are available. To read the measurements from the view pane, enable the Generate Report to Window check box. See Reading the Measure tool report on page 208 Changing display options When you print a map, it is identical to the map on your computer screen by default. There may be times when you do not want your printed work to look exactly like your screen. The display Options panel lets you turn off the default WYSIWYG feature. There are several reasons for disabling the WYSIWYG feature. For example, your software performance may improve when WYSYWYG is 112

115 turned off and the view pane appears less cluttered. (See About the Display Options dialog box on page 113 ) About the Display Options dialog box The Display Options dialog box lets you turn off the default WYSIWYG feature. It also provides WYSIWYG options for width/fill, pattern, text, and zoom scaling. WYSYWYG Options: Allows you to switch the WYSYWYG feature on or off, or to choose from a set of custom WYSYWYG options. On: Enables WYSYWYG for map publishing. Off: Disables WYSYWYG for map publishing. Custom: Enables the width/fill, pattern, and text options. Width Fill: Displays the map with WYSIWYG line weights and polygons filled. Pattern: Displays the map with all the patterns visible. For example, a pattern can be a broken line or other symbol, such as sand, transmission lines, or forest. Text: Displays the map with its text attributes applied (for example, font, height, and so on). Scale representation when zooming: Changes the vector display size relative to the zoom level. When you zoom in, symbols get bigger and lines get wider. Customizing the Focus toolbars You can customize the Focus toolbars to show or hide specific tool groups from the Toolbar Configuration dialog box. 1. From the View menu, click Toolbars and then click Customize. 2. Click in the Visible column next to a toolbar to show or hide it. A check mark indicates that the toolbar is available. 3. Click OK. About the Toolbar Configuration dialog box The Toolbar Configuration dialog box contains a table with a list of toolbar options. You can select the tool groups you want to see from the table. 113

116 Toolbar: Lists the available toolbars. Visible: Shows the option box for the toolbar listed in the Toolbar column. A check mark indicates that the toolbar is available. 114

117 Chapter 3 Supported layer types Generic Database (GDB) technology is available in Focus. You can work with dozens of file formats and convert them to PCIDSK. The following section outlines technical information for layers supported by GDB in Focus. Focus and raster layers In Focus, a GDB can have any number of raster image layers. Also referred to as channels or bands, a raster layer consists of a rectangular grid or array of pixels. Each pixel has associated digital numbers indicating its display brightness. Digital values can also represent attributes other than radiometry. A thematic raster layer can have a set of values, representing a crop type or a forest type, corresponding to the ground truth for a scene or image. Raster layers can also contain values for continuous fields of data relating to temperature, proximity to fire stations, or probability of erosion. You can assign raster layer values manually, automatically, or from the metadata associated with the raster layer. In Focus, all raster layers have a data type and must have the same width, measured in pixels, and height, measured in lines. Layers are presumed to correspond to the same real-world region. Focus supports four raster data types: 8-bit unsigned (8U): Each pixel is stored as one byte of data, and can have an integer value from 0 to bit signed (16S): Each pixel is stored in two bytes of data, and can have an integer value from to bit unsigned (16U): Each pixel is stored as two bytes of data, and can have an integer value from 0 to bit real (32R): Each pixel is stored as four bytes of data, and can have an IEEE floating point value between -1.2 x 1038 and 3.4 x Focus can also use bitmaps as 1-bit raster layers. When bitmaps are used as graphic masks, they are stored as separate layers. File formats supported by GDB are mapped to one of the four data types they most closely resemble. In some cases, mapping leads to loss of precision. For example, a file format that supports double precision (64-bit) floating point values is mapped to 32R with a corresponding loss of precision. A data type with 4-bit integers in TIFF files, are mapped to 8-bit unsigned format with no loss of precision. Raster layers are automatically numbered starting at 1. A 24-bit TIFF file is represented as a three-channel raster containing the following assigned channels: 115

118 channel 1 - red channel 2 - green channel 3 - blue Raster pixels are addressed as pixel and line locations in the pixel array. The top-left corner is addressed (1,1) and appears at offset (0,0) from the origin. Pixel values increase to the right, along the X axis, and line values increase downwards along the Y axis. Some calculations require operations at a finer level. Pixel values are divided to allow for more data. For example, the upper-left corner of the upper-left pixel is at 0.0 and 0.0, and the lower-right corner of the upper-left pixel is at 1.0 and 1.0. The centre of the upper-left pixel is at 0.5 and 0.5. The centre of the lower-right pixel of a 1000 x 1000 image is at and Metadata Focus uses the following metadata tags for raster layers: DEFAULT_PCT_REF - Reference to the pseudo-color table (PCT) segment for displaying an image in pseudo-color mode. This entry defaults the image to pseudo-color display mode. DEFAULT_LUT_REF - Reference to a look-up table (LUT) segment for a default enhancement when displaying an image. SCALING_MIN - Default value to use as a minimum for scaling an image channel to 8-bit for display purposes. SCALING_MAX - Default value for maximum scaling in an image channel to 8-bit for display purposes. NO_DATA_VALUE - Image value indicating no data is available. ELEVATION_UNITS - May be UNKNOWN (implicit default), FEET, or METRES. Primarily intended for use with elevation channels and should be UNKNOWN for non-elevation data. Class_n_Name - Short name for a theme class in a raster with #n# being the class number. Should be less than 9 characters. Class_n_Desc - Longer description for a class in a raster. Class_n_Color - Color for displaying a particular theme class. Value is the color encoding using the RGB (rrr ggg bbb) convention as seen in the PCLColor class. ACQUISITION_DATE - Date and time an image was acquired. The format of date is YYYY/MM/DD HH:MM:SS. Segment organization PCIDSK is a data structure for holding digital images and related data, such as LUTs, spectral signatures, ground control points, and other data types. Each PCIDSK database is a separately named disk file. You can have any number of PCIDSK files, limited only by the disk capacity of the computer. PCIDSK files can be shared with users on different computer platforms. Segments are the parts of a PCIDSK database which hold data related to the imagery in the database. Unlike image channels, disk space is not allocated for segments at the time the database is created; rather, disk space is dynamically allocated whenever a segment-generating program is executed. A database can store up to

119 segments, provided you have enough disk space. Twelve kinds of information are stored as segments, namely: Bitmaps [Type 101:BIT] Bitmap segments are pseudo-images. They have the same pixel and line dimensions as the image data on the PCIDSK file; however, each pixel of a bitmap is only 1-bit deep. In other words, the gray value of a bitmap pixel can be either zero (pixel not #on#) or 1 (pixel #on#). For viewing purposes, bitmaps are opened to video in graphic (or bitmap) planes. Bitmap pixels with a value of 1 are visible (they take on the color of the graphic plane). Bitmaps are used most commonly for delineating masks or training areas. Vectors [Type 116:VEC] Vector segments hold lists of (X,Y,Z) vertices, which define point and line structures representing river networks, political divisions, and so on. These segments also contain attribute information in a number of different formats and projection information. Signatures [Type 121:SIG] Signature segments hold statistical data that describe the spectral behaviour of a particular image feature (object). Signature segments are used as input during minimum distance, parallelepiped, and maximum likelihood classification. Text [Type 140:TEX] Text segments hold attribute data (some quality, such as land use, or quantity, such as temperature) linked to the gray levels of a particular image channel or free-form text (legend information used during map generation or commands to implement an analysis model). Other specifically formatted text segments include an AVHRR segment containing calibration and orbital data, including: Satellite ID (name), orbit ID, year, day of year. Spatial extent information. A single GCP corresponding to the exact center of the middle pixel from the first line of the output image. Orbital element/ephemeras data: epoch, inclination, right ascension, argument of perigee, eccentricity, mean motion, mean anomaly. Ascending/descending orbit flag. Platinum resistance temperatures. Internal target values for channels 3,4,5. Gray level of space values for channels 3,4,5. Up to 5 LUTs used to compress 10-bit data to 8-bit. If a particular output channel is not 8-bit, no LUT for that channel will be created. These LUTs are used by the program named SST. Georeferencing [Type 150:GEO] Georeferencing segments hold mathematical transforms that map all pixel locations in the database image to a georeferenced coordinate system (such as UTM). Orbit [Type 160:Orbit] Orbit segments hold satellite ephemeras data, used in the orthorectification process. This information is read 117

120 from the original data source, or from a text file. Look-up Table [Type 170:LUT] LUT segments hold numerical tables that map image gray levels to new gray levels. Pseudo-Colour Table [Type 171:PCT] Pseudo-colour segments hold numerical tables which map image DN values to a specific color. Colors are defined by an intensity value (between 0 and 255) for each of a red, green, and blue component. Binary [Type 180:BIN] Binary segments are created and used by PACE programs. These contain internal-only information, such as orthorectification models and neural networks. Array [Type 181:ARR] Array segments hold an array of numbers. They are created and used by PACE programs. They contain information such as SAR-gain offsets and gain-scaling tables. System [Type 182:SYS] The system segment is used to hold binary information that you should not normally access directly. System segments are not displayed by utility programs and are used to hold information such as metadata, overviews, and tiled-image data. Ground Control Points [Type 214:GCP] GCP segments hold pairs of (X,Y) coordinate positions that locate a point in an image and some other frame of reference (either a vector segment, a map, another image, or keyboard input of coordinates) for purposes of image correction, registration, and mosaicking. Each segment has a numeric-type code. For example, GCP segments are type 214. This numeric code helps you locate a particular segment in a database. When listing segments with the program ASL, you can create a listing by segment type. If you do not know the numeric code for a particular segment type, consult the list above or use: AST Database Segment Type Codes Pseudo-color Tables A PCT segment contains an array of 256 colors and assigns color values to 8-bit images. A PCT always contains exactly 256 entries. File formats, such as TIFF, which may have color tables with less than 256 colors, assigns a value of zero to unused colors. There is no support for alpha channels in the table. Look-up Tables The LUT segment consists of bit values, between 0 and 255. It is used to apply enhancements to raster data. It can also be used to encode thematic class mapping. 118

121 Ground Control Points GCP segments contain up to 256 GCPs, which are used to associate projection coordinates with locations on an uncorrected raw image. GCPs can also be used to relate locations in any two georeferencing systems: in raw image coordinates and in a georeferencing projection system. The definitions of the georeferencing systems are kept as 16-character map unit strings. Projection parameters are not stored. Only projections that are fully defined by the map unit string can be used; for example, UTM, Long/Lat, or METRE. Complex projections, such as Transverse Mercator, cannot be used. Each control point can have an elevation associated with the location in an image. An elevation unit string is kept for each system with values in meters or feet. GCPs have the following associated values: Id: Unique numeric control point identifier. System 1 X: The X coordinate in the first georeferencing system and is a pixel located in the image. System 1 Y: The Y coordinate in the first georeferencing system and is a line location in the image. System 1 Elevation: The elevation of the location in the first georeferencing system. This has a zero value and is ignored by applications. System 2 X: The X coordinate in the second georeferencing system and is a location described in projection coordinates. System 2 Y: The Y coordinate in the second georeferencing system and is a location described in projection coordinates. System 2 Elevation: The elevation in the second georeferencing system. This has a zero value when it is not used. Bitmap (BIT): A bitmap segment is a raster layer where pixels have a value of 0 or 1. Bitmap segments are typically used to mask images when creating training areas in classification. Bitmaps are raster grids, similar to image layers, and must have the same number of pixels and lines as other raster layers in the database. The georeferencing 119

122 associated with the raster layers is assumed to apply to bitmap layers. Vector (VEC) Vector layers or segments hold a set of related vectors and can be points, polylines (arcs), whole polygons, topological polygons, or additional database records. Vector objects in Focus are called shapes. A shape has a unique numeric identifier (ShapeId) greater than or equal to zero. A ShapeId is assigned chronologically beginning at zero. Each shape has an associated record of attributes stored in the layer as part of the shape. Each shape has a list of vertices recorded in double precision IEEE floating point numbers and has an X, Y, and Z value. Vertices are coordinates in the vector georeferencing system. Topological layers Focus lets you work with the layer attributes for several topological file formats. The following information shows the required attributes for different formats: Arc layers Arc layers must contain the following attributes: StartNodeId: Contains the GDBShapeId of the starting node. EndNodeId: Contains the GDBShapeId of the ending node for this arc. LeftAreaId: Contains the GDBShapeId of the left area polygon, or GDBNullShapeId if there is no area. RightAreaId: Contains the GDBShapeId of the right area polygon, or GDBNullShapeId if there isn#t such an area. Node layers: Node layers must contain the following attribute: ArcIdList: (GDBFieldTypeCountedInt) List of arc ShapeIds starting or ending at this node. Each node should also have one vertex defining the position of the node. A node layer must have ARC_REF and AREA_REF metadata pointing to the related arc and area layers. It must also have a LAYER_TYPE of TOPO_NODES indicator in metadata. Area layers Area layers must contain the following attribute: 120

123 ArcIdList: (GDBFieldTypeCountedInt) List of arc ShapeIds forming the border of this area in clockwise order. Each ring is separated by a GDBNullShapeId entry in the ArcIdList. A topological area shape should have either zero or one vertex. If it has one, it will be presumed to be an internal label point for the area. An area layer must have NODE_REF and ARC_REF metadata pointing to the related node and arc layers. It must also have a LAYER_TYPE of TOPO_AREAS indicator in metadata. Representation Style Tables (RST) The Representation Style Table (RST) is used to describe and store the graphical attributes of a vector layer. Each element is assigned an integer value called a representation code or RepCode. The representation consists of a series of parts describing a drawing method for a shape. Each part has the following information: Priority: Used to indicate how vector drawing components are layered. Higher priority layers are drawn over lower priorities. This applies to different parts in a representation. It also applies to different shapes in a layer, and sometimes between vector layers in a view. GeoGateway has the following drawing elements: Simple-line Dash-line Spaced-symbol Simple-point Point-symbol Vector-text Solid-polygon Patterned-fill Transparent-polygon Parameters: Each element has a set of parameters affecting the display. For example, the parameters of the Simple-line element are width and color. Importing, linking, and translating data Although GDB operates behind Focus, there are times when you need to work with more than one file format. The import, link, and translate utilities expand your ability to read, view, and process distribution formats, and read, edit, and write exchange formats. Use these utilities when you need to import different file formats to a PCIDSK file, link files, translate data across different formats, transfer layers, import ASCII files into your project, or export your project as an XML file. With some geospatial file formats, the size and configuration of the data may cause slow-downs when operations and algorithms are applied to the data. Focus 121

124 is optimized to use the PCIDSK format. Focus has utilities to import, link, and translate file formats to let you get the most out of both PCIDSK- and GDB-supported file formats. Importing files to the PCIDSK format The import utility lets you work with any GDB-supported format in Focus by automatically converting it to a PCIDSK file. When the format is not supported by GDB, you must define the raw data with the Raw File Definition tools. (See Using undefined image data on page 127 ) To import files into Focus using the Import File utility, you must select a source and a destination file. The Import file utility also has Interleaving and Overview options. The Browse button opens the File Selector dialog box. Use this dialog box to select the file you want to import into PCIDSK format. Destination File: Specifies the new PCIDSK version of the source file. Enter the file name and path directly in the Destination File box, or click Browse to launch the File Selector dialog box. The output file must not exist before importing the file. Format Options: You can improve the performance of a file and save disk space when you are using large files. There are several interleaving and compression methods available for raster data. Overview Options: An overview is a reduced-resolution version of the imported image. Focus can open overviews faster than full resolution images and automatically creates a set of overviews for an imported image. Overviews can increase the required disk space by as much as 15 percent. 1. From the File menu, click Utility and then click Import to PCIDSK. 2. From the PCIDSK Import dialog box, click Browse for the source file. 3. In the File Selector dialog box, locate the file you want to import and click Open. 4. From the PCIDSK Import dialog box, click Browse for the destination file. 5. Choose a location for your destination file. Note:You can also type the name of the file directly in the Destination File box. 6. Type a name for your file in the File name box. 7. Click Save. 8. Select a format from the Format Options list box. 9. Select a downsampling option from the Overview Options list box. If you want to disable the overview, select Disable Overview. 10. Click Import. The file is not opened in the view pane. You must 122

125 open the file separately. Building raster overviews The Build Raster Overviews dialog box lets you choose target files and layers, resample methods, and overview levels. You can create overview levels in powers of 2, which lets you obtain a minimum image size of 64 pixels in one dimension. Overviews can be created for file formats that do not natively support overviews. Overviews cannot be created for a layer if one of its dimensions is less than 8 kb. 1. In Focus, click the File tab if it is not already displayed. 2. Right-click a raster layer. 3. From the menu, choose Overview Manager. The Build Raster Overviews dialog box is displayed. 4. In the Build Raster Overviews dialog box, in the General Information section, do one of the following: click the File arrow and choose a file. click Browse and choose a file. 5. Click the Layer arrow and choose a layer. You can build an overview for all layers or for a single layer, which lets you create different overviews for different layers. The raster size and type are automatically displayed for the selected layer. 6. In the New Overviews section, click the Resampling type arrow and choose one of the following resampling types: Nearest neighbour downsampling Block averaged downsampling Block mode downsampling 7. Do one of the following: Click Number of Levels and choose a level. Click Overview Decimation Levels and type a number in the box. The maximum number of overview levels that can be created are displayed. 8. Click Run. The Existing Overviews section shows all overviews associated with a layer. The section lists the type of sampling, the associated number of levels, and the overview decimation levels. Deleting raster overviews You can delete raster overviews associated with a layer. 1. In the Build Raste Overviews dialog box, click the Delete Overviews check box. 2. Click Run. Linking PCIDSK and other databases 123

126 The Link utility protects source data by creating an empty PCIDSK database and allowing indirect access to imagery on both GDB-supported and PCIDSK files. Auxiliary information, such a LUTs or bitmaps are transferred to the newly created PCIDSK file. Linking files allows several users to work with data while preserving the integrity of the source files. You can access data across a network or on the same system disk without duplicating large files. Imagery is not copied or transferred; instead, pointers are created to describe the directory location and layout of data. Changes are saved to the linked file only. The link file copies auxiliary information such as LUTs, PCTs, bitmaps, vectors, and georeferencing information. You can link to a remote source file, select a destination file, and set overview options. Source File:The Browse button beside the Source File box opens a File Selector dialog box. Use it to select the file you want to link to. Destination File:Specifies the new version of the PCIDSK source file. Enter the file name directly in the Destination File box, or click Browse to open the File Selector dialog box and create a new path and directory for the link. Overview Options: Produces a reduced-resolution overview of the imported image. You can choose an option for creating overviews. You can also choose to disable the overviews. 1. From the File menu, click Utility and then click Link. 2. In the PCIDSK Link dialog box, click Browse next to Source file. 3. In the File Selector dialog box, navigate to and select the source file for linking and click Open. 4. In the PCIDSK Link dialog box, click Browse next to the Destination file box. 5. In the File Selector dialog box, choose a location for your destination file. If necessary, create a new file folder. 6. Type a file name in the File name box. 7. Click Save. 8. In the PCIDSK Link dialog box, select an overview option from the Overview options list box. 9. Click Link. Translating file formats The Translate utility can translate from one GeoGateway supported file format to another or create a new PCIDSK file from a GeoGateway format using only the layers you specify. In the Translate File dialog box you select similarly georeferenced source and destination files and then share layer information between the two files. After choosing source and destination files you can specify source layers in the source file to include in the translation. 1. From the File menu, click Utility and then click Translate. 2. In the Translate (Export) File dialog box, click Browse next to the Source file. 3. In the File Selector dialog box, navigate to and 124

127 select the source file and click Open. 4. In the Translate (Export) File dialog box, click Browse next to the Destination file box. 5. In the File Selector dialog box, choose a location for your destination file, type a file name in the File name box, and click Save. If necessary, create a new file folder. 6. In the Translate (Export) File dialog box, select the format you want to use from the Output format list box. 7. In the Source Layers area, select the data files that will make up your destination file from the View list box. 8. Select an item from the Source Layers list and click Add. You can remove a layer from the Destination Layers list by selecting it and clicking Remove. 9. Click Translate. Importing and converting ASCII files The Import ASCII Table/Points Wizard can import ASCII files into a project and convert them into vector-point data. Table values that combine coordinates with field research data can be imported to the Attribute Manager spreadsheet and converted into vector-point files that you can add to a project and open as layers in the view pane. Using the Import ASCII Table/Points wizard You can use the Import ASCII Table/Points wizard to import and convert tabular ASCII data. You can format your ASCII data the same way you would when using a common spread sheet application. In the wizard, selecting the Delimited option from the Data Format area allows you to specify a formatting character for the table columns. You can either select a delimiter or specify another delimiter by enabling the Other check box and identifying the character in the Other box. The Data PreView area displays an updated version of information. The wizard detects delimiters and file formats when you open a text file. When you select the Fixed Width data format and click Next, the dialog box allows you to identify the number of characters in a column within a fixed width formatted file. The Import ASCII Table/Points Wizard has three steps 1. Import and format delimited or fixed width ASCII files. When you select a file, you can overwrite an existing layer or create a new one. The Display Result option automatically shows results in the view pane when you have completed the step3 of the wizard. 2. Identify delimiters or set field widths before converting your ASCII data into tabular format.the Data Type area allows you to identify how the ASCII data is formatted; by a character or fixed width. In the Import Options area you can choose to either import all records or specify a range of records to import. 3. Select data types for the fields in your table and convert to vector points. Tabular ASCII data does not require georeferencing to be converted with the wizard. Degrees, minutes, and seconds are not imported as coordinates but as fields 125

128 only. The wizard imports ASCII files only, but can output to PCIDSK (.pix) format. The preview area is similar to the Notepad text editor and allows you to see the ASCII information table before it is formatted. 1. Step 1 a. From the File menu, click Utility and then click Import ASCII Table/Points. b. In the Input area of the Import ASCII Table/Points Wizard, click Browse. c. In the File Selector dialog box, select an ACSII-format file and click Open. d. Enable one of the following options: e. Display - vector points are opened in the view pane and are not saved. f. Save - click Browse next to the File list box and choose a location for saving the output. If you want to save your output to a specific layer within the file, select one from the Layer list box. g. Enable the Delimited option in the Data Format area. If you want the first line of data displayed as a header row, enter a number of 1 or higher in the Header row spin box. h. Click Next. 2. Step 2 a. In the Delimiters area, enable a check box next to any correct delimiter type for your file.you can see the required delimiter in the preview area between each record. The Data preview area changes to a table when you choose the correct option. b. Click Next. 3. Step 3 a. In the Coordinate Fields area, select values from the X, Y, and Z list boxes. The remaining inputs for the Projection area are activated and the Import attributes list is updated. b. Enter the projection and bounds information in the Projection area. c. Click Finish. Formating fixed width files 1. With your text file open in Step 1 of the wizard, enable the Fixed width option. 2. Set the number of records and header rows you want in your converted file. 3. Click Next. 4. In the Data preview area, click the # of Characters column in the Field 1 box and type the number of characters you want to allocate to this field. 5. Press Enter. 6. Repeat step 4 and step 5 until all fields are added and formatted properly. 7. Click Next. 8. Follow the instructions in Step 3 of the wizard. Opening data from a remote data source 126

129 You can open data from an Oracle database, a Web service, a URL, and through Open Database Connectivity (ODBC) as long as the data formats are compatible with GDB technology. Focus supports read and write access to Oracle8i and Oracle 10g Spatial. For more information, refer to #ORACLE# in Supported File Formats under Technical References in the Geomatica Help. A Web service provides access to data published on the servers connected to the Web. You can access any Web mapping service (WMS) or Web feature service (WFS) complying with the OGC Web Mapping or Feature Service specifications, and display the data as a layer in the Focus project. The data is read-only. For details about the Web services, refer to #Selecting Data from Remote Data Sources# under Common Utilities in the Geomatica Help and the Geomatica WebServer Suite Installation Guide. ODBC creates a connection between Geomatica and a data source such as Microsoft TM Access. For more information, refer to #ODBC# in Supported File Formats under Technical References in the Geomatica Help. 1. From the File menu, click Open. 2. In the File Selector dialog box, click Remote Data. Using undefined image data You can open undefined or raw image data the same way you would any other file. In the File Selector dialog box, locate and select your raw imagery and click Open. When you open raw images the Raw Imagery File Definition dialog box opens automatically, allowing you to define the raw imagery file format. The following controls are available to define data: Header Bytes Specifies the number of bytes to allocate for header information. The zero value, indicates that imagery data starts at the very beginning of the file. Image Size defines the X (Pixel) and Y (Line) size of the image file. These should be the full size of the image in the file, even if you only wish to open a sub-set of the file. Number of Channels Indicates the number of channels or planes of image data stored in the file. Data Interleaving Indicates how multiple channels of image data are interleaved. This field is not applicable for one channel image files. However, single-band data can have band interleaving. PIXEL: The channels are pixel interleaved. For example, in a 127

130 three-channel file, the values in the file are , with the channel values for a given pixel located together. LINE: The channels are line interleaved. The data for line 1 of the first channel occurs first, followed by the data for line 1 of the second channel and line 1 of the third channel. Next is line 2 of the first channel, and so on. For example, in a three-channel file, the values in the file would be (line 1) , (line 2) , and so on. BAND: The channels are band sequential. All the data for the entire first channel would be first, followed by all the data for the second channel, and so on. Data Type: The set of options to define the type of data. 8-bit Unsigned The data for each channel are 8-bit, unsigned. 16-bit Unsigned The data for each channel are 16-bit, unsigned. Values range from 0 to 65535, and are two bytes each. 16-bit Signed The data for each channel are 16-bit, signed. Values range from to 32767, and are two bytes each. 32-bit Real The data for each channel are 32-bit IEEE floating point numbers. Each value is 4 bytes long. Byte Order options for storing the order of multiple-byte data words. Used for non-8-bit image data only, it can be ignored for files containing only 8-bit data. Least Significant Byte first (LSB) This order is common on IBM computers with Intel 80 x 86 architecture. It is sometimes known as swapped or little endian. In LSB order, a 16U-pixel value of 1 would be expressed as two bytes, the first a 1, and the second a 0. Most Significant Byte first (MSB) This is the order common on Sun, IBM, RS/6000, HP, SGI, and Mac systems. It is also known as unswapped, big endian, or Motorola order. In MSB order a 16U-pixel value of one would be expressed as two bytes, the first a zero, and the second a one. The default selected on the panel is the byte order of the local system. In the Raw Imagery Definition dialog box, click Accept. A new header file is created with the file name extension.pox. 128

131 The new raw configuration file is an auxiliary file that contains layout information for the imagery that you provide. Focus automatically recognizes the new raw file without redefining it. The following is an example of the file produced for a simple 1000 x bit single-channel image. Auxiliary Target: rawimage.bil Raw Definition: ChanDefinition - 1: 8U Swapped Once the.pox file is created, you cannot define the raw file again until the.pox file is deleted. When experimenting with possible raw file definitions, an.pox file is not recommended. You can work directly with all items in the control pane under both the Maps and Files tabs. You can rename and remove data whether or not you are working with a project file. Image metadata support Metadata refers to a specific image in a PCIDSK file. All images and associated metadata are considered image data sets. Channels, other than those containing image data set bands, can exist in a PCIDSK file. Metadata is not associated with ancillary raster data or raster maps produced from image analysis. Focus supports image metadata to accommodate hyperspectral processing and analysis through PCIDSK files. Image metadata must be formatted as an XML document in a text file. The METAIN program reads the metadata from the XML document and writes it to a metadata segment in the PCIDSK file that contains the associated image data. Existing metadata is overwritten. The METAOUT program reads metadata from a segment in the PCIDSK file and formats it as an XML document. The required format of an image metadata XML document is specified by the XML schema stored in the PCI ImageMetadata.xsd file if the $PCIHOME/etc directory of the Geomatica installation CD. Working with projections Projections are required to tie down an image to the earth#s surface. Once the required projection information has been defined and the image has been corrected to overlay the projection bounds, image equirectangular pixel and line coordinates can be transformed to produce equirectangular projection easting and northing coordinates which can be transformed with the projection formulas to produce equivalent non-equirectangular longitude and latitude coordinates. Longitude and latitude coordinates can also be transformed to projection easting and northings and image database pixel and line 129

132 coordinates. Understanding PCIDSK projection definition Projections can compensate for distortions in large-scale imagery that cover a large earth surface, where distortions are produced from earth curvature. These are the same distortions that occur in projecting a spherical surface (the Earth) onto a flat surface (the image database). Although there are still distortions in all projections, some are removed or compensated for depending on the projection used. Once an image is tied to one projection, it can automatically be projected to overlay another projection. This gives you options to process your data by matching goals to the appropriate projection. The software used for the projection transforms is the General Cartographic Transformation Package (GCTP), produced by the U.S. Geological Survey, and can be used to convert: projection coordinates to geographic coordinates. geographic coordinates to projection coordinates. projection coordinates to coordinates in a second projection. Transforms between different earth models is discussed under the EARTH MODELS sub-topic. Supported projections The following table lists the projections supported in Focus. The information for each projection is repeated at the top of the projection sub-topic in the PROJECTION section. Table 8. Supported Projections Code Class Name Earth Model ACEA AE CASS EC ER GNO conic azimuthal cylindrical conic cylindrical azimuthal GOOD pseudocylindric GVNP azimuthal Albers Conical Equal Area Azimuthal Equidistant (or Zenithal Equidistant) Cassini (or Cassini-Soldner) Equidistant Conic (or Simple Conic, or Conic) Equirectangular (or Equidistant Cylindrical, or Simple Cylindrical, or Rectangular, or Plate Carree) Gnomonic (or Gnomic) Goode#s Homolosine Gen Vert Near-Side Perspective ellipsoid or sphere sphere ellipsoid or sphere ellipsoid or sphere sphere sphere sphere sphere 130

133 Code Class Name Earth Model KROV conic Krovak Bessel 1841 LAEA LCC LONG/ LAT azimuthal conic not a projection Lambert Azimuthal Equal-Area (or Zenithal Equal-Area) Lambert Conformal Conic Longitude/ Latitude (or Geographic) sphere ellipsoid or sphere ellipsoid or sphere MC cylindrical Miller Cylindrical sphere MER MSC cylindrical Mercator modif azimuthal Modif Stereographic Conformal (or Alaska Grid) ellipsoid or sphere Clarke 1866 (NAD27) OG azimuthal Orthographic sphere OM cylindrical Oblique Mercator (or Oblique Cylindrical, or Orthomorphic, or Hotine) PC conic Polyconic PS azimuthal Polar Stereographic ellipsoid or sphere ellipsoid or sphere ellipsoid or sphere Code Class Name Earth Model ROB RSO cylindrical Robinson Rectified Skew Orthomorphic sphere ellipsoid or sphere SG azimuthal Stereographic sphere SIN SOM SPCS TM UPS UTM VDG pseudocylindric pseudocylindric modif cylindric usually conic or cylindrical cylindrical azimuthal cylindrical Sinusoidal (or Sanson- Flamsteed) Space Oblique Mercator State Plane Coordinate System Transverse Mercator (or Gauss-Krueger) Universal Polar Stereographic Universal Transverse Mercator miscellaneous Van der Grinten Defining a new projection sphere ellipsoid or sphere Clarke 1866 (NAD27) or GRS 1980 (NAD83) ellipsoid or sphere ellipsoid or sphere ellipsoid or sphere sphere A set of parameters can be specified for projections supported as generic and opened using the name of the 131

134 projection set. User-defined projections are shown under the User Projections tab in the Other Georeference Units dialog box. By accepting a user projection, the supported projection and the associated parameters are recognized. You can view the parameters for the projection by clicking More after accepting the User Projection that has been selected. New projections are stored in a text file named userproj.txt that may exist either locally or in the $PCIHOME/etc subdirectory, or both. New user projections may be brought into the system by editing userproj.txt with a text-editor and adding the parameters for the projection. A template of the fields supported is included in userproj.txt that exists in the etc sub-directory in the comment lines at the top of the file. When working with new projects, keep these rules in mind: Each non-comment line will consist of a field identifier (e.g. ProjectionName) and a value for the field (e.g. 'UKNatGrid'). There would be one or more spaces separating the field identifier and the field value. The field identifier and value must fit on one line. Although the present user projection examples have the field identifier first followed by the field value, the field value followed by the field identifier is also supported. Processing for the field identifiers is not case-sensitive, so it doesn#t matter if upper or lower case or some combination of the two is used. Blank lines are acceptable in the file and will be skipped. If a field value has spaces in it, it should be enclosed in double-quotes. For example, ProjectionDescription 'British National Grid.' Comments follow an exclamation mark. If the line begins with an exclamation mark, the whole line is a comment. Trailing comments in a given line are acceptable. Processing for a given projection begins when a 'ProjectionName' record is read and ends with the next 'ProjectionName' record or when the end of the file is reached. Other than that the order of the other records for the projection does not matter. Different projections require different parameters. These fields can be defined for any user-defined projection set: ProjectionName: This is the user-defined name that will be presented for the projection set. This can be 11 printable characters at most. For example, ProjectionName 'UKNatGrid.' ProjectionDescription: This is the descriptive text to present with the ProjectionName. Although there is no maximum size, the ProjectionDescription should be short and no more than 64 characters. If there are spaces in the description, it should be enclosed in double-quotes. For example, ProjectionDescription 'British National Grid.' MapUnits: These are the actual units of the projection set and would correspond to the units string built up by using the 'Generic Projections'. This can be 16 characters at most. 132

135 For example, you can use either MapUnits 'tm e9' or MapUnits 'TM E009.' Defining datums and ellipsoids Ellipsoids: Using ellipsoids rather than datums is still valid as long as there are not different horizontal datums involved in reprojecting between different map projections. If there are different horizontal datums that use the same ellipsoid, datum codes should be used. If ellipsoid codes are used, the software incorrectly assumes that the ellipsoid is for the same datum. The following defaults are provided where there is a reprojection involving datum shifts: For #E000# (Clarke 1866) or #E008# (GRS 1980): Areas within Canada, Bulk of Canada: 141 W to 44 W; 49 N to 84 N; Western Ontario: 95 W to 85 W; 48 N to 49 N Southern Ontario, West: 85 W to 79 W; 42 N to 49 N; Southern Ontario, East: 79 W to 74 W; 42d30# N to 49 N; Southern Quebec, West: 74 W to 70 W; 45 N to 49 N; Southern Quebec, East: 70 W to 68 W; 47 N to 49 N; Atlantic area: 68 W to 44 W; 43 N to 49 N; #E000# (Clarke 1866) defaults to and#147;d-03and#148; (NAD27 (Canada, NTv1)) #E008# (GRS 1980) defaults to #D-04# (NAD83 (Canada, NTv1)) Areas outside Canada, #E000# (Clarke 1866) defaults to #D-01# (NAD27 (USA, NADCON)) #E008# (GRS 1980) defaults to #D-02# (NAD83 (USA, NADCON)) #E019# (Normal Sphere) defaults to #D800# #E012# (WGS 84) defaults to #D000# #E005# (WGS 72) defaults to #D186# New Ellipsoids A new ellipsoid not supported at present can be defined by adding an entry in the ellipsoid text file. To add the definition once so it is globally available to all users (and if you have write-permission to the file), the new definition would be added to $PCIHOME/etc/ellips.txt. Or the new definition may be added to a local copy of the file. (This would not be globally available to all users.) At the operating system level (on a Unix platform in this example), you could copy the files as follows: % cp $PCIHOME/etc/ellips.txt % chmod 644 ellips.txt A local copy of ellips.txt will be searched before (and so has priority over) $PCIHOME/etc/ellips.txt. To define a new ellipsoid, add the new ellipsoid definition as one line of text to the ellips.txt file. For example: #E910#,#ATS77#, , Where the fields of the new ellipsoid record are as 133

136 follows: E910 - A unique code for the ellipsoid.this would be one that does not already exist in the file. The first character would be E (or e), for ellipsoid, followed by an integer (maximum of 3 characters). ATS77 - A descriptive string for the earth ellipsoid. This descriptive isn#t used at present in the software but a field is expected. An empty character string could be used The ellipsoid semi-major axis in meters The ellipsoid semi-minor axis in meters. If datum shifts are involved, the datum that uses the new ellipsoid would have to be defined. To do this see the NEW DATUMS topic. Reprojecting files When you add new data, it is automatically reprojected based on the data you already have open. When you open large, secondary files of a different projection, they are also automatically reprojected, which can make the work slower. You may encounter this situation, for example, when a work file has a UTM projection and you open a file with an LCC projection. If you open the UTM data first, Focus must reproject the LCC to UTM. In such cases, it is recommended that you reproject the data manually and save it as a new file. You can reproject both raster and vector data if the data is in a valid projection, it is in a GDB-supported format, and you know which datums were used. A datum is a mathematical surface used to make geographic computations. An ellipsoid defines the dimensions of the earth. The datum includes the ellipsoid used and its position relative to the center of the earth. Each datum references one ellipsoid, but an ellipsoid can be referenced by one or more datums. If you compare the position of a point calculated using one datum and then calculate the same position using a different datum, the coordinates of the point will be different, even if the datums refer to the same ellipsoid. Since a datum is a mathematical surface used to make geographic computations, it is possible to convert from one datum to another. However, reprojecting a file from one ellipsoid to another will not provide the correct results because the critical information contained in a datum is not defined in the ellipsoid. About the Reproject dialog box The Reproject dialog box lets you reproject data. You can select data, set reprojection bounds, and work with selected layers in the source and destination layers. Destination files are automatically created in PCIDSK format. Reprojections can be exported as any GDB-compatible format. Browse: Opens the File Selector dialog box to select source data or a destination file, depending on the button you click. 134

137 Source Files: Reports your source files. Destination Files: Reports your Destination files. Output Format Allows you to choose a GDB file format for your output. Options: Lets you enter an option for your output data. Reprojection bounds The Reprojection Bounds area allows you to select the combination of parameters to use for reprojection. It also lets you add your reprojection information. Size: Lets you enter the size of your reprojection bounds in lines and pixels. Pixels: Lets you enter the number of pixels for your reprojection. Lines: Lets you enter the number of lines for your reprojection. Pixel Size: Allows you to set the pixel size along the X and Y axes. X: Lets you enter a value for the pixel X size. Y: Lets you enter a value for the pixel X size. Projection Method: Lets you enter a value for the pixel Y size. Earth Model: Lets you select a projection method for your reprojection. More: Opens the Earth Models dialog box, where can select datums and elipsoids. Bounds: Lets you choose either geographic or geocoded bounds measurements. Upper Left: 135

138 Lets you enter either geocoded or geographic coordinates for the upper-left corner of the reprojection. Lower Right: Lets you enter either geocoded or geographic coordinates for the lower-right corner reprojection. Pixel Size X: Reports the size of the X pixels. Pixel Size Y: Reports the size of the Y pixels. Resampling: Lets you choose a re-sampling method. Transform Order: Lets you choose an order of transformation. Sampling Interval: Lets you enter a sampling interval value. Selectable layers and reprojection The Selectable Layers area allows you to choose the source and destination layers for the reprojection. Source Layers: Lists the layers in your source files. View: Lets you choose the data types you want to include in the reprojection. Select All: Selects all of the data listed in the Source Layers area. Add: Moves the selected layers in the Source Layers area to the Destination Layers area. Destination Layers: Lists the layers that will be included in the reprojection. Remove: Removes selected layers form the Destination Layers list. Select All: Selects all of the layers listed in the Destination Layers list. Reprojection: 136

139 Runs the reprojection. 1. From the Tools menu, click Reprojection. 2. In the Reproject dialog box, click Browse next to the Source file. 3. From the File Selector dialog box, locate and select the file that will provide the projection. 4. Click Open. 5. Click Browse next to the Destination file box and select a destination file from the File Selector dialog box. 6. Locate the directory where you want to save the reprojected file. 7. Type a name for your reprojected file in the File name box. 8. Click Save. Setting reprojection bounds Select one of three methods for determining the bounds of the data that is to undergo reprojection. Pixels/lines and bounds: Varies the pixel size to create a file with the pixel, lines, and bounds values that you select. Pixels/lines and resolution: Varies the bounds based on the resolution of the source file. Bounds and resolution: Inputs the file size in pixels and lines, and changes the pixel size. You can choose from either geocoded or geographic reprojection bounds. Geocoded: Displays the upper-left and lower-right bounds in northings and eastings. Geographic: Displays the upper-left and lower-right bounds in latitude and longitude. Specifying a coordinate system When your imagery has no georeferencing, you can use the pixels in the raster file as the coordinate system. 1. Select Pixel from the Coordinate System list box. 2. From the UTM Zones dialog box, select a zone from the list. 3. Click Accept. 4. From the UTM Rows dialog box, select a row from the list. 5. Click Accept. Selecting an ellipsoidal earth model The coordinate system defaults to the coordinate system of the source file. For example, if UTM 11 E000 is the coordinate system of the source file, UTM 11 refers to 137

140 UTM Zone 11 and E000 is the Ellipsoidal Earth model E000-Clarke This is shown in the text box to the right of the Earth Model button. 1. In the Reprojection Bounds area, click Earth Model. 2. In the Earth Models dialog box, click the Ellipsoids tab and select an Earth model. 3. Click Accept. Selecting the earth model 1. In the Reprojection Bounds area, click Earth Model. 2. In the Earth Models dialog box, click the Datums tab and select an Earth model. 3. Click Accept. Selecting the SPCS coordinate system 1. Choose SPCS from the Coordinate System list box, to the left of the Earth Model button. 2. From the State Plane Zones dialog box, choose a zone. 3. Click Accept. Selecting a different coordinate system 1. Choose Other from the Coordinate System list box, to the left of the Earth Model button. 2. From the Other Projections dialog box, click the Generic Projections tab and choose a georeferencing unit. 3. Click Accept. 4. In the Projection Definition dialog box, type a longitude in the Longitude column of the True Origin box. 5. Type a latitude in the Latitude column of the True Origin box. 6. Click Accept. Maximum bounds and resampling methods You can reset the bounds, using the Maximum Bounds command, after the output projection has been defined and before using the Reproject command. The maximum bounds are derived by projecting the upper-left and lower-right corners. The Maximum Bounds function can also project 441 points or 21 pixel positions by 21 scan line positions, distributed over the entire input image. You can reset the maximum bounds to their original values by clicking the Maximum Bounds command. The resampling method affects image reprojection only. You can change the resampling method by selecting the nearest neighbour, bilinear interpolation, or cubic convolution. Bitmaps are automatically resampled using the nearest-neighbor method. You can change the resampling method by opening the Resampling list and choosing a method you want to use. Transformations are computed from 256 ground control 138

141 points based on the projection transformation. Exact Transformation The default order that performs a calculation for each pixel in the file. Polynomial Transformations As the polynomial order increases, the accuracy generally increases, but the reprojection process becomes slower. Thin Plate Spline Transformation Is based on fitting splines to the ground control points. The Thin Plate Spline method is more accurate than the polynomial methods but results in a slower reprojection process. The transform order approximation is only applied when reprojecting imagery and bitmaps. The vertices of vector layers are transformed exactly. For sampling intervals higher than one, the reprojected position is calculated at every sampling interval. A linear interpolation is performed for the in-between values. To control the spacing in the calculation of the reprojected position, set the sampling interval from one to a maximum value of four. Selecting database layers for reprojection After specifying your reprojection, you can select the layers to use for your destination file. You can list layers of a similar type that you wish to work with; for example, you can show all available files in the source list. 1. From the View menu, click BIT Segments. 2. In the Source File Layers list, choose a file name and click Add. If you want to reposition an item in the Destination File Layers list, select it and click the up or down arrow button. If you want to select the entire list in the Destination File Layers list box, click Select All. 3. Click Reproject. The reprojected file is not opened in the view pane. You must open the file separately. Organizing and editing layers In Focus, geographic features and their attributed data are stored in layers. Each layer of information can either represent a single set of geographic information, such as hydrography, or a combination of information features. In a layer, raster and vector data are stored just like areas stored in Maps. Layer information can be displayed and can consist of lines, polygons, and symbols that represent project information. You can build a map by 139

142 placing each layer on top of the other. In the Maps tree, each layer appears as a branch belonging to an area. Layers let you organize and edit the features in a map. You can break a map into multiple layers, each containing a portion of the overall content. Most layer tasks are specific to the layer type, but many functions are common to both image and vector layers. You can show or hide layers in the Maps tree. To work with a layer, you must make it active. Note: You can add new features to the active layer only. A pencil icon indicates the layer is active. To display a layer 1. In the Maps tree, enable the check box next to a layer. A check mark next to a vector layer in the Maps tree indicates that the layer is open in the view pane. If you cannot see an open layer, it may be covered by another layer. To make a layer active 1. In the Maps tree, select the layer you want to activate. A pencil icon indicates the layer is active. To move a layer 1. In the Maps tree list, drag the layer up or down in the tree. A line indicates where the layer will be placed. To copy a layer 1. In the Maps tree, right-click a layer and click Copy. 2. Right-click where you want to paste the layer and click Paste. To remove a layer 1. In the Maps tree, right-click a layer remove and click Remove. The layer will be removed from the map, but the layer data is not removed from the data file. To rename a layer 1. In the Maps tree, right-click a layer and click Rename. 2. Type a new name and press Enter. Adding and removing imagery You can create a new layer for your map when you want to add digitized map information, digitize an image file, or create different layers of geographic information. 140

143 You can create a new layer by right-clicking an area icon and using the shortcut menu to add new raster, vector, or bitmap layers. When you create a new layer, you must set the parameters of the new area. New layers are automatically rescaled and georeferenced to the area. Any areas with undefined projections use the meter projection by default. You can change the layer type, data type, and the georeferencing when you set up the layer parameters. When you create a new layer, the parameters describe the amounts and kinds of data you can use in the layer properties. Creating a new raster layer Raster layers are most often used as background for vector-based maps. You can also use raster images for thematic maps. In the Maps tree, image layers are always a sub-level of an area. You can use several types of image files. The table below shows a list of supported image file types with a description of each. Table 9. Data Type Description 8-bit Pixel values 0 to bit Signed Pixel values -32,768 to 32, bit Unsigned Pixel values 0 to 65, bit Real Pixel values - 1.2x1038 to 3.4x In the Maps tree, right-click an area and click New Raster Layer. 2. In the New Raster Layer dialog box, enable an option in the Layer Type area. 3. In the Data Type area, enable an option for the data type you want. 4. Enable an option in the Georeferencing area and fill in the appropriate information. 5. Click OK. Creating a new bitmap layer In Focus, a bitmap layer acts as a graphical layer that can be used to mask regions in your imagery for a variety of purposes. You can create a new empty bitmap layer when you want to work with raster information in a layer of lower priority. 1. In the Maps tree, right-click an area and click New Bitmap Layer. 2. In the New Bitmap dialog box, enable a Georeferencing option and fill in the appropriate information. 3. Click OK. Creating a new vector layer You can create a new empty vector layer when you want to use digitized map information, break your map into different layers with specific geographical information, or when you want to create vectors on top of an image in the view pane. 1. In the Maps tree, right-click an area and click New 141

144 Vector Layer. 2. In the New Vector Layer dialog box, enable a Layer Type option. 3. Enable a Georeferencing option and fill in the appropriate information. 4. Click OK. Setting vector layer attributes Layer data, such as symbols, lines, filled areas, polygons, and text, are stored and categorized separately in RepCodes. The RepCode defines each feature by a set of coordinates and descriptive labels. The features are shown as a layer within an area. Each map element requires its own RepCode. RepCodes also link the vector files to the RST, and tell the system how to show each feature on the screen. The View Attributes dialog box is a spreadsheet for vector layer information.you can use it to view and edit point data in vector files, and to work with RepCodes. To view vector properties 1. In the Maps tree, right-click a vector and click Properties. To view vector attributes 1. In the Maps tree, right-click a vector and click Attribute Manager. To change the magnification of the preview image, click the zoom commands below the Preview area. Setting vector layer properties General vector layer properties define how the layer is displayed on screen. To set up general vector layer properties 1. In the Maps tree, right-click a vector layer and click Properties. 2. In the Vector Layer Properties dialog box, click the General tab. 3. In the Description field, enter a description of the layer. 4. Enable or disable any of the following check boxes: Read Only: enabling this option prevents the vector layer from being changed. Visible: enabling this option makes the layer visible in the view pane. 5. Enter a value that represents the layer priority in the Priority box. Layer priority may cause one layer to mask another in the Maps tree. If you cannot see a layer in your map, check the layer priority. Changing layer priority is necessary to present a vector layer over a raster layer or a bitmap layer. 6. Click OK. You can save a vector layer as part of a.pix file that contains your work or as part of a project file. 142

145 To save a vector layer 1. In the Maps tree, right-click a layer and click Save. 2. In the New Layer Detected dialog box, choose the Output File, the file format and, if applicable, the channels you want to save. 3. Click Save. Transferring layers You can transfer layers by copying them from a source file and saving them to a destination file. The transferred data can either be added on to a new layer or overwritten in the destination file. For example, you can specify that a PCT segment in the source file be added as a new segment in the destination file or you can specify that a PCT segment is overwritten in a destination file. The source file is never modified when it is transferred; however, the destination file is always changed. You can transfer any GDB-supported files. Some non-pcidsk file formats may not be compatible. Georeferencing cannot be transferred between files. Input imagery is changed to match the destination file dimensions. Use the Transfer Layers dialog box to select similarly georeferenced source and destination files and to share layer information between the two files. Source File: Opens the File Selector dialog box where you can select a file with the layers you want to copy. Destination File: Opens the File Selector dialog box where you can select a file to receive the data layers. Source Layers: Shows a complete list of all channels, bitmaps, and vectors in the source file. You can choose the layers you want to copy to the destination file, list layers by type in the list window, or you can select all. Destination Layers: Shows a list of all channels, bitmaps, vectors in the destination file. Source layers that you have chosen to add or overwrite also appear in this list. Click the Remove and Select Transferred command buttons if you want to undo transfer relationships. 1. From the File menu, click Utility and then click Transfer Layers. 2. In the Transfer Layers dialog box, click Browse next to the source file. 3. In the File Selector dialog box, locate the file with the data you want to transfer and click Open. 4. Click Browse next to the destination file and locate the file to where you want to transfer your layers. 5. Click Save. 143

146 6. Choose a layer type from the View list box. 7. Select the layers that you want to transfer and click Add. 8. Click Transfer Layers. Working with data tools Focus has tools designed to help you produce new files from your existing data. You can create new data files by saving existing files as other formats. You can also clip images to produce new files and you can create subset files that maintain the attributes of the original data. Changing data formats You can convert several file types to different formats by saving them as the format you want directly from the Maps tree. The following files types can be converted: Bitmap Greyscale RGB RST SYM PCT About the Bitmap Save As dialog box The bitmap Save As dialog box allows you to save a bitmap from the Maps tree. You can save the file to a layer within the target file or to a new layer. In the Maps tree, bitmaps are listed whether they are saved or not. In the Files tree, however, bitmaps are listed only if they are saved. For each saved bitmap, both the file and layer names are displayed. Input: The Input section displays the name of the layer and the data type that you are about to save. Output: The Output section allows you to choose the target file and format in which you want to save the bitmap. You can also select a layer within the target file or create a layer for the bitmap. File: The File list allows you to select the file in which you want to save the bitmap. If the file is not listed, you can browse and select the file. Format: The Format list allows you to select the format in which you want to save the bitmap. Options: The Options button opens the GDB Options dialog box. (See Selecting GDB format options on page 145 ) Layer: 144

147 The Layer list allows you to select a layer within the target file or create a layer for the bitmap. About the Vector Save As dialog box The Vector Save As dialog box lets you save a vector layer from the Maps tree as another file format. You can save the file to the original layer or to a new layer. Input: Reports the location of the layer and the data type with which you are working. Layer: Reports the layer type for the current layer. Save selected shapes only: Saves only the shapes you have selected in the view pane or the Attribute Manager. When no shapes are selected, the option is disabled. If you have shapes selected and you want to overwrite the original segment, the option is disabled. Save selected fields only: Saves only the selected fields. When no fields are selected, the option is not available. Output: Lets you choose a target file for saving your new vector data, select a format for the new data, and choose or create a layer within your target file. File: Lets you select a target file for your new vector data from a list. Browse: Opens the File Selector dialog box, letting you choose a different target file, not showing in the File list. Format: Lets you choose an output format from the list of available formats. Options: Opens the GDB Options Editor. (See Selecting GDB format options on page 145 ) Layer: Lets you choose a target layer from a list of layers. You can also choose to save your new file to a new layer. Selecting GDB format options The GDB Options Editor lets you configure the GDB format you have chosen for your output. Some of the 145

148 GDB formats do not have data type options. 1. Click the Options button. 2. In the GDB Options Editor, choose any of the file options you want for your output data. For more information about the specific option for the selected file format, click the Help button on the GDB Options Editor. 3. Click OK. About the Grayscale Save As dialog box The Grayscale Save As dialog box lets you save a bitmap from the Maps tree in another file format. You can save the file to the original layer or to a new layer. Input: Reports the location of the layer and the data type with which you are working. Layer: Reports the layer type for the current layer. Raster with attribute data: Saves the raster and its associated attribute table. Raster only: Saves only the raster data. Save selected shapes only: Saves only the records that you have selected in the Attribute Manager. When no records are selected, the option is not available. Save selected fields only: Saves only the fields that you have selected in the Attribute Manager. When no fields are selected, the option is not available. Output: Lets you choose a target file for saving the layer, select a format for the new file, and choose or create a layer within your target file. File: Lets you select a target file for your new layer. The Browse button lets you choose a file not showing in the File list. Format: Lets you choose an output format from the list of available formats. Options: Opens the GDB Options editor. (See Selecting GDB format options on page 145 ) Layer: 146

149 Lets you choose a target layer from the list of layers. You can also choose to save your new file to a new layer. Properties: Opens the Output Layer Properties dialog box. About the Output Layer Properties dialog box The Output Layer Properties dialog box lets you set the properties for your new output layers when you convert a file to another GDB-supported format. You can select an output type, change the layer scaling, and save original file enhancements as an LUT. Output Type: Lets you change the bit depth for your output file by choosing from a list of available bit depth values. For example, 8-bit, 16-bit, or 32-bit, depending on the values shown in the list. Scaling: Lets you choose a scaling method for your output file. (See Scaling images on page 257 ) Enhancement: Lets you choose and set a default LUT. Output Lookup Table: Lets you select an available LUT and gives you the option to have no LUT for your file or to save an LUT as a new layer. Save as default look-up table: Lets you choose to assign an LUT as the file default. About the PCT Output Layer Properties dialog box The Output Layer Properties dialog box lets you save the color table with the PCT layer. Output Color Table: Lets you save the PCT color table as a new layer. Save as default look-up table: Lets you choose to assign the color table as the file#s default. About the RST Save As dialog box The RST Save As dialog box lets you save a copy of an RST file from the Maps tree to another target file. You can save the file to the original layer or to a new layer. Input: Reports the location of the RST file with which you are working. 147

150 Output: Lets you choose a target file for saving your new bitmap, Select a format for the new file and choose or create a layer within your target file. File: Lets you select a target file for your new bitmap. The Browse button lets you choose a file not showing in the File list. Browse: Opens the File Selector dialog box. Format: Lets you choose an output format from the list of available formats. Description: Lets you change the name of the saved RST. About the RGB Save As dialog box The RGB Save As dialog box lets you save an RGB file in the Maps tree to another file format. You can save the file to the original layer or to a new layer. You can also select channels and change channel properties. Input: Reports the location of the layer and the data type with which you are working. Output: Lets you choose a target file for saving your new RGB file, select a format for the new file, and choose or create a new layer within your target file. File: Lets you select a target file for your new RGB file. The Browse button lets you browse for a file not shown in the File list. Browse: Opens a File Selector panel so you can choose a target file at a different location. Format: Lets you choose an output format from the list of available formats. Options: Opens the GDB Options Editor. Layer: Lets you choose a target layer from the list of layers. You can also choose to save your new file to a new layer. 148

151 There are three of these list boxes Properties: Opens the Output Layer Properties dialog box. There are three of these buttons. About the PCT Save As dialog box The PCT Save As dialog box lets you save a PCT segment in the Maps tree as a PCIDSK (.pix) file. If you are saving a layer containing a map from a Web mapping service to your local drive, you must also save its color table or the map may not have the same representation the next time you open it. To save the color table, click Properties. Input: Reports the location of the layer and the data type with which you are working. Layer: Reports the layer description for the current layer. Raster with attribute data: Raster only: If the layer contains attributes, the Raster only option becomes available. When it is clicked, the raster data is saved without the attribute data. Save selected shapes only: If the layer contains attributes and shapes are selected, the Save selected shapes only option is available. When it is enabled, only the records that you have selected in the Attribute Manager are saved in the file. If you have shapes selected and you want to overwrite the original segment, the option is disabled. Save selected fields only: If the layer contains attributes and fields are selected, the Save selected fields only option is available. When it is enabled, only the fields that you have selected in the Attribute Manager are saved in the file. Output: Lets you choose a target file for saving the layer and lets you choose or create a new layer within your target file. File: If the layer contains attributes, the Raster with attribute data option becomes available. When it is clicked, the raster and its associated attribute table is saved to the file. Lets you select a target file for your new layer. Browse: Opens the File Selector dialog box, where you can 149

152 browse for a file not shown in the File list. Format: Contains only the PCIDSK format. Options: Opens the GDB Options Editor. (See Selecting GDB format options on page 145 ) Layer: Lets you choose a target layer from the list of layers. You can also choose to save to a new layer. Properties: Opens the Output Layer Properties dialog box. About the LUT Save As dialog box The LUT Save As dialog box lets you save a lookup table (LUT) in a file. Input: Reports the LUT with which you are working. Layer: Reports the LUT for the current layer. Raster with attribute data: If you are saving the image with the LUT and the layer contains attributes, the Raster with attribute data option becomes available. When it is clicked, the raster and its associated attribute table is saved to the file. Raster only: If you are saving the image with the LUT and the layer contains attributes, the Raster only option becomes available. When it is clicked, the raster data is saved without the attribute data. Save selected shapes only: If you are saving the image with the LUT and the layer contains attributes and shapes are selected, the Save selected shapes only option is available. When it is enabled, only the records that you have selected in the Attribute Manager are saved in the file. Save selected fields only: If you are saving the image with the LUT and the layer contains attributes and fields are selected, the Save selected fields only option is available. When it is enabled, only the fields that you have selected in the Attribute Manager are saved in the file. Output: Lets you choose a target file for saving the LUT, select a format for the file, and choose or create a new layer 150

153 within your target file. File: Lets you select a target file for your LUT segment. Browse: Opens the File Selector dialog box, where you can browse for a file not shown in the File list. Format: Lets you choose an output format from a list of available formats. Options: Opens the GDB Options Editor. (See Selecting GDB format options on page 145 ) Layer: Lets you choose a target layer from the list of layers. You can also choose to save your LUT to a new layer. Properties: Opens the Output Layer Properties dialog box. Opening the Clipping/Subsetting panel Clipping and subsetting data are effective methods working with large data sets. In research and testing situations, you may want to create subsets of a large data base. By working with small representative areas, you can reduce processing times or you can use file subsets to test an image process. When you obtain a promising result on a subset, you can repeat the process on a larger, more complex scene. Before creating a subset or a clip, you should consider the output format. A subset file is based on the file type of the source file by default. You can change the output format of a subset to any GDB-compatible data type. For some file types you may want to add or remove information. The Clipping/Subsetting process lets you choose the file data type for a clip or subset with the GDB Options Editor. When you have selected a file, you can work with the Available Layers list. The list of layers depends on the output format you have chosen. For example, if you select a format that only supports vector data (for example, SHP format), only vector layers are listed. Note: If vector georeferences are not compatible with the source file, vectors in the segment are not clipped. A warning message shows a list of incompatible vector segments. Georeferencing is compatible when they are equal, or when one is an under specified form of the other. From the Tools menu, click Clipping/Subsetting. 151

154 Clipping and subsetting images When using the Clipping/Subsetting feature, you must specify the bounds of a clip or subset and then run the process. For more information, see Opening the Clipping/Subsetting panel on page From the Clipping/Subsetting dialog box, choose a file from the File list box in the Input area. If the file is not listed, click Browse and choose a file from the File Selector dialog box. 2. Enable the layers that you want to clip from the Available Layers list. A check mark indicates the layers that will be clipped. 3. In the Output area, choose a file from the File list box. If the file is not listed, click Browse and choose a file from the File Selector dialog box. If you want to use the Select a Script Subset File Definition Method, you can leave the File box empty. 4. Select the file format that you want for the output from the Format list box. If you want to select specific options for the format, click Options and select options from the GDB Options Editor. 5. Enter a value that you want to use for pixels without data in the output file in the Initialization Value spin box. Use a value that does not occur in the image being clipped. If you want to give the initialization value the metadata tag of no data, enable the Set as No Data Value check box. 6. If you want to save the defined clip region boundary as a vector layer in the output file, enable the Output Clip Boundary Vector check box. 7. Depending on how you want to use to clip the image, select one of the following options from the Definition Method list box: User-entered Coordinates: enters the corner coordinates for the clip region. All layers will be clipped to fit that region. See Defining the clip region with user-entered coordinates on page 153. Select a File: uses a smaller, intersecting file to define the bounds of a subset. See Defining the clip region by selecting a file on page 153. Select a Clip Layer: uses a smaller, intersecting layer from a file to define the bounds of a subset. See Defining the clip region by selecting a layer on page 154. Select a Named Region: bases the clip on a named region you created in Focus. See Defining the clip region by selecting a named region on page 154. Select a Script Subset File: creates several clip regions on the same image. You can create a text file containing the coordinates and the output file name; Focus automatically produces the series of subset files. See Defining the clip region by selecting a script subset file on page 154. Use Current View: bases the clip on the region displayed in the view pane. Only 152

155 available from Area view. See Defining the clip region using the Zoom tools on page Click Clip. Defining the clip region with user-entered coordinates You can define the clip region by manually entering coordinates for the exact area of the data you want to save as a subset. The following procedures follow step 7 in Clipping and subsetting images on page 152. To set the clip region 1. In the Definition Method list box, choose User-entered Coordinates. 2. In the Coordinate Type list box, choose one of the following formats to define the coordinates for the clip region: Raster extents: defines the clip region by identifying upper-left and lower-right pixel and line coordinates. Geocoded extents: defines the clip region by identifying the georeferenced coordinates of the upper-left and lower-right corners. Long/Lat extents: defines the clip region by identifying the geographic coordinates of the upper-left and lower-right corners. Raster offset/size: defines the clip region by identifying the pixel and line coordinates of the upper-left corner and providing the number of pixels in width and the number of line in length. Geocoded offset/size: defines the clip region by identifying the georeferenced coordinates of the upper-left corner and providing width and length in the units of measurement of the input coordinate system. 3. In the Upper Left boxes, type the coordinates for the top-left corner of the clip region. If you selected Raster extents, Geocoded extents, or Long/Lat extents from the Coordinate Type list box, type the coordinates for the bottom-right corner of the clip region in the Lower Right boxes. If you selected Raster offset/size from the Coordinate Type list box, type a value representing the number of pixels in the Width box and type a value representing the number of lines that you want to form the clip region in the Height box. If you selected Geocoded offset/size from the Coordinate Type list box, identify the size of the clip region. Using the measurement unit of the projection, type the distance for the width in the Width box and type the distance for the height in the Height box. 4. Click Clip. To change a clip area with the bounding outline 1. In the Preview area, drag a bounding outline corner until you have the size you want. 2. Drag the bounding outline to a new location. 3. Click Clip. Defining the clip region by selecting a file 153

156 You can use a smaller intersecting file to define the bounds of a subset. The Select a File Method requires two files. You use one file as input and the other to define the subset. The definition file must be smaller than the source file. The following procedures follow step 7 in Clipping and subsetting images on page In the Define Clip Region area, choose Select a File from the Definition Method list box. 2. Choose a file from the File list box. If the file is not listed, click Browse and choose a file from the File Selector dialog box. 3. Click Clip. Defining the clip region by selecting a layer You can also use a smaller intersecting layer to define the bounds of a subset. The Select a Clip Layer method works the same way as the Select a file method. You can use one layer as input and another layer to define the subset. The definition layer must be smaller than the source layer. The following procedures follow step 7 in Clipping and subsetting images on page In the Define Clip Region area, choose Select a Clip Layer from the Definition Method list box. 2. Choose a file that you want to use as the clip region from the File list box. If the file is not listed, click Browse and choose a file from the File Selector dialog box. 3. Choose a layer from the Layer list box. If the layer contains vectors, you can use only the selected shapes in the layer to define the clip region. To use only the selected shapes, enable the Clip using selected shapes only check box. 4. Enable one of the following options: Extents: uses the rectangular extents of the vectors as the clip region. Shape(s) Boundary: uses the actual area covered by the vectors as the clip region. 5. Click Clip. Defining the clip region by selecting a named region You can use the bounds of a named region to define a subset clip. You must have at least one named region in the source data to use this method. Named regions can only be saved as Geomatica Project (.gpr) files. The following procedures follow step 7 in Clipping and subsetting images on page In the Define Clip Region area, choose Select a Named Region from the Definition Method list box. 2. Choose a named region from the Named Region list box. 3. Click Clip. Defining the clip region by selecting a script subset file You can create several clip regions on the same image. When you create a text file containing the coordinates and the output file name, Focus automatically produces 154

157 the series of subset files. For more information, see Creating the text file for Script Subset File method on page 155. The following procedures follow step 7 in Clipping and subsetting images on page In the Define Clip Region area, choose Select a Script Subset File from the Definition Method list box. 2. Choose one of the following formats from the Coordinate Type list box: Raster extents: if the clip region is defined by identifying upper-left and lower-right pixel and line coordinates. Geocoded extents: if the clip region is defined by identifying the georeferenced coordinates of the upper-left and lower-right corners. Long/Lat extents: if the clip region is defined by identifying the geographic coordinates of the upper-left and lower-right corners. Raster offset/size: if the clip region is defined by identifying the pixel and line coordinates of the upper-left corner and providing the number of pixels in width and the number of line in length. Geocoded offset/size: if the clip region is defined by identifying the georeferenced coordinates of the upper-left corner and providing width and length in the units of measurement of the input#s coordinate system. 3. Choose the text file containing the coordinates and the output file names from the File list box. If the file is not listed, click Browse and choose a file from the File Selector dialog box. 4. Click Clip. You can verify for errors in the Focus Message Center. Creating the text file for the Script Subset File method You can create several clip regions from one file by using the Script Subset File method. With this method you create a text file containing the bounds of the clip regions and list the output file names for each clip. Focus uses the text file to automatically produce separate files containing the subset of the data. When you create the text file, you need to define the bounds of the clip regions and the file names using a particular format, depending on what you selected in the Coordinate Type box on the Clipping/Subsetting dialog box and which file format is selected in the Format box under Output (see Clipping and subsetting images on page 152 ). Each line in the text file contains the data for one clip region. The line is divided into fields separated by spaces. Each field contains a piece of information about the size of the clip region and where to save the file. Raster extents: The clip region is defined by identifying upper-left and lower-right pixel and line coordinates. The format for 155

158 listing the pixel and line coordinates and the file name is as follows: ul_x ul_y lr_x lr_y path and filename Where: ul_x is the pixel coordinate for the upper-left corner of the clip region ul_y is the line coordinate for the upper-left corner of the clip region lr_x is the pixel coordinate for the lower-right corner of the clip region lr_y is the line coordinate for the lower-right corner of the clip region For example: C:\Clip1.pix C:\Clip2.pix Geocoded extents The clip region is defined by identifying the georeferenced coordinates of the upper-left and lower-right corners. ul_x ul_y lr_x lr_y path and filename Where: ul_x is the x coordinate for the upper-left corner of the clip region using the same projection as the input file ul_y is the y coordinate for the upper-left corner of the clip region using the same projection as the input file lr_x is the x coordinate for the lower-right corner of the clip region using the same projection as the input file lr_y is the y coordinate for the lower-right corner of the clip region using the same projection as the input file For example: C:\Clip1.pix C:\Clip2.pix Long/Lat extents: The clip region is defined by identifying the geographic coordinates of the upper-left and lower-right corners. The extents can be defined suing a number of different formats such as the following example. For more information, see the online help for LONG/LAT INPUT under Projection Reference in the Technical Reference. ul_x ul_y lr_x lr_y path and filename Where: 156

159 ul_x is the longitude value for the upper-left corner of the clip region ul_y is the latitude value for the upper-left corner of the clip region lr_x is the longitude value for the lower-right corner of the clip region lr_y is the latitude value for the lower-right corner of the clip region For example: 117d46'10"W 33d44'55"N 117d40'10"W 33d38'55"N C:\Clip1.pix 117d35'22"W 33d40'30"N 117d30'22"W 33d33'30"N C:\Clip2.pix Raster offset/size: The clip region is defined by identifying the pixel and line coordinates of the upper-left corner and providing the number of pixels in width and the number of line in length. ul_x ul_y width height path and filename Where: ul_x is the pixel coordinate for the upper-left corner of the clip region ul_y is the line coordinate for the upper-left corner of the clip region width is the number of pixels from the upper-left corner to the upper-right corner of the clip region height is the number of lines from the upper-left corner to the lower-left corner of the clip region For example C:\Clip1.pix C:\Clip2.pix Geocoded offset/size: The clip region is defined by identifying the georeferenced coordinates of the upper-left corner and providing width and length in the units of measurement of the input's coordinate system. ul_x ul_y width height path and filename Where: ul_x is the x coordinate for the upper-left corner of the clip region using the same projection as the input file ul_y is the y coordinate for the upper-left corner of the clip region using the same projection as the input file width is the distance from the upper-left corner to the 157

160 upper-right corner of the clip region. height is the distance from the upper-left corner to the lower-left corner of the clip region. For example: C:\Clip1.pix C:\Clip2.pix Defining the clip region using the Zoom tools You create your clip from the region displayed in the view pane. It is only available in Area view mode. The following procedures follow step 7 in Clipping and subsetting images on page Open the file that you want to clip. 2. From the View menu, click Area View Mode. 3. Use the zoom tools to display the area that you want to clip in the view pane. 4. From the Tools menu, click Clipping/Subsetting. 5. In the Define Clip Region area of the Clipping/Subsetting dialog box, choose Use Current View from the Definition Method list box. 6. Click Clip. Creating multiple subset tiles You can create multiple subset files using the tiling feature on the Clipping/Subsetting dialog box. In the Clipping/Subsetting dialog box preview window, the bounding outline is replaced by a grid to help you divide the data into the number and size of tiles you want. After you have selected and prepared the data you want to work with, you access the tile output controls by clicking the Tile Output command button. You can choose from two tiling methods and you can control the amount of overlap between each file. When you process the data, Focus creates a new file based on each tile and the input data you selected. 1. In the Clipping/Subsetting dialog box, click Tile Output. 2. In the Tile Definition area, choose one of the following options from the Definition Method list box: Use tile size and overlap:creates tiles based on the size measurement values that you enter in the Tile Size X and Y boxes. Use number of tiles and overlap: creates tiles based on the values you enter in the Number of Tiles X and Y boxes. 3. Choose a unit of measure from the Units list box. The Geocoded option derives the tile coordinates from the input data. You can move and re-size the tile bounding grid to any location within the preview window. 4. Enter values that represent the amount of overlap you want between each of your subset files in the Overlap X and Y boxes. 5. Click Clip. Selecting a clip region 158

161 A clip region focuses attention on a location by hiding the rest of the area from view. The concealed areas remain available and are included in any processes that you employ. You can create a subset or clip of the data. (See Opening the Clipping/Subsetting panel on page 151 ) 1. Open the Clipping Layer list and choose the layer that you want to use to define the extents of the clip region. If you want to view only the selected shapes, enable the Clip using selected shapes only check box. 2. Click OK. Opening the Data Merge wizard You can combine a group of files, regardless of bounds, projection, data type, or resolution into a single output file with the Data Merge Wizard. When you start the Data Merge Wizard, follow the instructions at the top of the wizard dialog boxes for each step. The following information gives an outline of how to add information to each of the Data Merge Wizard dialog boxes. If a layer does not have a proper projection, it will not be available; however, LUT, PCT, and GCP layers can be transferred even if the source files have no georeferencing. A warning message opens when georeferencing is not compatible. The Data Merge Wizard has three steps: choosing input layers, setting the output and georeferencing, and setting up output layers. From the Tools menu, click Data Merge. Choosing an input layer 1. In the Data Merge Wizard, click Browse. 2. In the File Selector dialog box, select the file you want to add and click Open. If you want to view the properties of a file, right-click the file in the Available Files/Layers list and click Properties. 3. In the Available Files/Layers list, enable a check mark next to any layer that you want to add as an input layer. 4. Click Next. Naming the output file In this step, you can set the georeferencing and reprojection parameters for the output. You can select a new or existing file to receive the merged layers. You must first name the file that will receive the merged data layers in the name box. 1. Choose a file and path from the Name list box. If the file is not listed, click Browse and choose a file from the File Selector dialog box. Existing files are not overwritten. The merged data is added to an existing file. 2. Choose an output file format from the Output format list box. 159

162 For information on format options, click the? button next to the Options box. When merged results are written to existing files, associated georeferencing parameter fields are not available in step 2 of the Data Merge Wizard. 3. In the Georeferencing Setup area, set the following items: Projection: You can get the map representation, assigned to the output file, from an existing file by selecting a file option or you can manually enter it. Extents: Are the upper-left and lower-right corner coordinates of the output file. The bounds can be based on an existing file, derived from either the union or intersection boundaries of all the input file, or it can be entered manually. Union: Output file extents are large enough to include all input file extents. No data is cropped. Intersection: The output file extents are based upon the region of overlap for all input files. Resolution: Pixel dimensions can be based on an existing file or can be entered manually. Reprojection Parameters have the following settings: Resampling: Bitmaps are automatically resampled using the nearest-neighbor, bilinear-interpolation, and cubic-convolution methods. Transform Order: You can choose from Exact, Thin Plate Spline, and 1st Order to 5th Order polynomial transformations. Each pixel in a file is included in the calculation. Sampling Interval: For sampling intervals higher than 1, the reprojected position is calculated at each interval. A linear interpolation is performed for the values in between. 4. Click Next. Setting up output layers Focus checks each of the input layers for inconsistencies in format and file projection. When inconsistencies are detected, a warning message appears. All inappropriate layers are ignored in the merge process. You can change the following layer attributes: Processing Order: The layer order you see in Step 3 of the wizard is the order in which layers are merged to the output file. By default, the order is what was selected in the Choose Input Layers step. To change the order, drag a layer up or down the list. Rename: To rename a layer, right-click the layer and click Rename. Remove: To remove a layer, right-click the layer and click Remove. 160

163 Set Parameters: To edit parameters, double-click a layer in the Select Layer(s) list. A parameters dialog box opens for the selected data type. Click Finish. Data Merge wizard - Set Bitmap Parameters dialog box You can change the parameters for any data type in the file tree. You can change several parameters for the output bitmap. You can identify the source file and layer, select a target layer or create a new one, and adjust both the order of transformation and sample interval. Input File: Reports the input bitmap you are working with. Input Layer: Reports the output layer where your input bitmap is located. Output Layer: Allows you to choose an existing output layer or to create a new one. Transform Order: Lets you choose a different transformation order for the bitmap output. The following transformation orders are available: Exact Thin Plate Spline 1st order 2nd order 3rd order 4th order 5th order Sampling Interval: Allows you to change the sampling interval for the bitmap file. Data Merge wizard - Set Image Parameters dialog box You can change the parameters for any data type in the file tree. You can change several parameters for the output bitmap. You can identify the source file and layer, select a target layer or create a new one, and adjust both the order of transformation and sample interval. Input File: Reports the input image you are working with. Input Layer: 161

164 Reports the output layer where your input image is located. Output Layer: Allows you to choose an existing output layer or to create a new one. No Data Value: Transform Order: Allows you to choose an order of transformation for your merged output. Sampling Interval: Allows you to change the sampling interval for the merged output. Lets you use a no-data value parameter in your output image file. Output Type: Lets you choose a bit-depth for your image output file. These output types are available: 8-bit unsigned 16-bit signed 16-bit unsigned 32-bit Scaling Function: Lets you choose a scaling function for your output file. (See Available scaling methods on page 258 ) Resampling: Lets you choose a resampling method for your merged output. (See Maximum bounds and resampling methods on page 138 ) 162

165 Chapter 4 Opening the Algorithm Librarian The Algorithm Library contains a set of predefined and user-defined programs that are organized in a tree structure. You can expand a category in the tree the way you would any other Windows application by clicking on the + next to a folder. When you expand a category or a sub-category, the items inside each folder are arranged in alphabetical order. Some folders contain sub-folders and some contain only a list of algorithms. The Algorithm Librarian dialog box allows you to search the algorithm directory tree. You can also create your own user-defined category folders to hold the algorithms that you use most often. (See Algorithm categories on page 164 andcreating user-defined categories on page 167 ). From the Tools menu, click Algorithm Librarian. You can search through the categories within each folder using the Find utility or you can browse through the categories based on the directory topics found in each folder. (See Finding an algorithm on page 166 ) About the Algorithm Librarian dialog box The Algorithm Librarian dialog box lets you work with the Algorithm Library. You can search the library and open a Module Control Panel (MCP) for the algorithms you want to use. (See Working with an algorithm MCP on page 170 ) Algorithm Library: Lists algorithms in a directory tree in the Algorithm Library pane on the left side of the Algorithm Librarian dialog box. You can expand the directory tree to browse, locate, and select algorithms. Open: Lets you open the Module Control Panel (MCP) for the algorithm you have selected in the algorithm library.(see Working with an algorithm MCP on page 170 ) Find: Opens the Find Algorithm dialog box. (See Finding an algorithm on page 166 ) Selected Algorithm: Displays the name of the algorithm and an icon representing the algorithm you have selected. Algorithm licensing Some algorithms may not be available with the 163

166 Geomatica license you have purchased. Files in the Algorithm Library that have a lock icon to the left of the algorithm name are not available. Contact for more information on your license package and for advice on the best Geomatica license for your needs. Algorithm categories Algorithms are organized by themes or categories into a directory tree containing two top-level categories. The Algorithm list can appear in two different ways. If created from a user-defined category, the Algorithm Library list opens with the User Defined category expanded and at the top of the directory tree. The PCI Predefined directory is collapsed and at the bottom of the directory tree. If you have not added a user-defined category, the Algorithm Library list opens with the PCI Predefined directory. In the PCI User Defined category, algorithms are listed in sub-category folders within a top-level folder. Moving down the directory tree, the top-level algorithm categories are: User Defined (top-level directory) PCI Predefined (top-level directory) All Algorithms All Bitmap Algorithms All Image Algorithms All Vector Algorithms Geomatica Analysis Classification Data Interchange Image Correction Image Processing Radar Analysis Spatial Analysis Utilities Algorithm sub-categories When you open the Algorithm Librarian dialog box, many of the top-level category folders contain several sub-category folders. The following lists show the sub-categories for each of the top-level folders. All Algorithms: Lists all the algorithms available in the Algorithm Library. All Bitmap Algorithms: Contains all the Geomatica algorithms that can be used with bitmap data. All Image Algorithms: Contains all of the Geomatica algorithms that can be used when working with Images. All Vector Algorithms: Contains all of the Geomatica algorithms that can be used with vector data. Geomatica: 164

167 Lists algorithms on the basis of your Geomatica license. This folder may contain a combination of six sub-categories, depending on your license: Fundamentals Prime Optical ATCOR3 Radar Hyperspectral Hyperspectral Image Compressor Pan Sharpening Analysis: Contains the following Geomatica algorithms for analyzing data: AVHRR DEM Analysis Favorability Analysis Geological/Geophysical Analysis Hydrological Analysis Hyperspectral Analysis Multi-layer Modeling Vegetation Analysis Classification: Contains six sub-category folders: Advanced Classification Data Exploration Neural Networks Post-Classification Analysis Supervised Classification Unsupervised Classification Data Interchange: Contains six sub-categories of algorithms: CD Reading/Utilities Image Interchange Oracle Database Loading Tape Reading Tape Writing/Utilities Text File Interchange Vector Interchange Image Correction: Has four sub-directories: Atmospheric Correction AVHRR Orbital Navigation Geometric Correction Image Mosaicking Image Processing: Has seven sub-directories: 3-D Rendering Data Fusion Enhancements Frequency Transforms Image Filtering Image Operations Image Transformations Radar Analysis: Contains four sub-directories: 165

168 Airborne Radar Analysis Polarimetric SAR Analysis SAR Speckle Filtering SAR Radar Analysis Spatial Analysis: Has five sub-directories: Utilities Proximity Analysis Overlay Analysis Topographer Conversion Tools Utilities: Has four sub-directories of utility algorithms: Interpolation PCIDSK Reports PCIDSK Utilities Vector Utilities Finding an algorithm All of the algorithms listed in the Algorithm Library show the name of an algorithm followed by a brief description of what it does. There are several ways to find algorithms: Open on page 164 the Algorithm Library and browse for algorithms that work with basic data types. For example, the PCI Predefined folder contains sub-folders for bitmap, image, and vector algorithms. Browse on page 164 through the categories by clicking the folders and sub-folders in the Algorithm Library tree. Search on page 166 for an algorithm using the Find Algorithm utility. You can decide which method to use based on the information you have about the algorithm and what tasks you want to perform on your data. (See Searching for an algorithm by category on page 167.) Using the Find Algorithm utility If you know the name of an algorithm you want or you are not sure, you can use the Find Algorithm utility to locate it quickly. You can search through the entire library using keywords to locate an algorithm, or you can search through the contents of a selected folder. 1. In the Algorithm Librarian dialog box, right-click a file folder and click Find. 2. In the Find Algorithm dialog box, type all or part of the algorithm name in the Find what box. 3. Enable any of the following check boxes: Match algorithm name # searches for an algorithm using the name of the algorithm. Match algorithm description using any keyword # searches the Algorithm Library based on any of the keywords you have entered in the Find what box. Match algorithm description using all keywords # searches the Algorithm Library based on all of the keywords you have entered in the Find what box. Wrap around searches through the Algorithm 166

169 Library continuously until you decide to stop. 4. Click Find Next. The Algorithm Librarian automatically opens the folder where your algorithm is located and the algorithm is selected. If you want to find another algorithm with a similar name, click Find Next again. Note: To search the entire contents right-click the All Algorithms folder or right-click anywhere inside the Algorithm Library other than on a file folder. You can also use the Find button to search the entire directory tree as well as a selected category. Searching for an algorithm by category The Find Algorithm dialog box lets you search through the algorithm library using the name of an algorithm or using keywords. You can also control the way the results of your search are displayed. Find what: Lets you enter either an algorithm name or a keyword description. Match algorithm name: Lets you search for an algorithm using the name of the algorithm. For a list of Modeler and Algorithm Library names and references see the Geomatica online Help. Match Algorithm description using any keyword: Lets you search the algorithm library based on any of the keywords you have entered in the Find what box. For example, with this option selected, a search on #Classify report# returns any algorithm with either of the words classify or report in the algorithm description. Match Algorithm description using all keywords: Lets you search the algorithm library based on all of the keywords you have entered in the Find what box. For example, with this option selected, a search on 'Lookup Table' returns only algorithms with both of the words Lookup and Table in the same algorithm description. Wrap around: The wrap around option lets you search through the algorithm library continuously until you decide to stop. When this check box is enabled, the Find Algorithm utility continues to show the results of the search each time you click Find Next. When this check box is disabled, the utility searches through the Algorithm Library once. When the search is completed, the Find Algorithm utility shows an End of search message. 1. Locate a category by scrolling down the Algorithm Library list and select the file folder for the category you want. 2. Click Find. 3. In the Find Algorithm dialog box, enter a name or keyword for the algorithm in the Find what box. 4. Enable a check box for any search criteria you want to use. 5. Click Find Next. Creating user-defined categories 167

170 The Algorithm Library contains a top-level, user-defined folder. You can create new folders in the User Defined folder to hold collections of your favorite algorithms. When you drag an algorithm icon from a PCI-predefined folder to a User Defined folder, a shortcut to the algorithm is created. A shortcut menu allows you to search user-defined folders, open and close any open MCPs, create new categories, show and hide folders, rename individual folders, and access online Help. The User Defined shortcut menu has the following options Find: Opens the Find Algorithm dialog box. (See Finding an algorithm on page 166 ) Close All Panels: Closes all open MCPs in the PCI-predefined folders. New Category: Adds a new folder to the User Defined folder. Hide: Hides the User Define folder. Show All: Shows all of the folders in the User Defined directory, including any folders that have been hidden using the Hide command. Rename: Lets you rename the User Defined directory. Help: Opens the Focus Help for the Algorithm Library. 1. From the Algorithm Librarian dialog box, right-click the User Defined folder and click New Category. 2. Type a name for the new category and press Enter. 3. If you want to add a second folder level to your new User Defined folder, right-click a new category folder and repeat the procedure. Adding algorithms to the user defined folder You can create a collection of shortcuts to your favorite algorithms by dragging the algorithms from a PCI-predefined folder to a User Defined folder. You can also create a shortcut by right-clicking a PCI-predefined algorithm and clicking Add to User Defined. 1. Right-click the user-defined folder and click Rename. 2. Type a new name and press Enter. Using an algorithm Every algorithm in the Algorithm Library has a Module Control Panel (MCP) that you can open from the 168

171 Algorithm Librarian dialog box. You use the MCP to control data inputs and outputs and to assign the required information for the results you want. In the Algorithm Librarian dialog box, right-click an algorithm and click Open. You can also double-click the algorithm. About module control panels Algorithm MCPs are tabbed dialog boxes. The number of tabs and the controls they contain vary depending on the data requirements and the number and type of parameters available to the algorithm. Not all algorithm MCPs look the same. You can encounter some variation in the algorithm MCP inputs, functions, and features. In general, a MCP has one tab each for file selection, input parameters, and log. The Files tab typically has a pane labelled Input Ports and may have a pane labelled Output Ports. The Input Params tab items vary according to the requirements of the algorithm you are using. Some MCPs also have an Output Parameters tab that contains controls for the algorithm output. Typically, an algorithm MCP has tabs and controls similar to those shown in the following example. Files tab Lets you direct the data that you want to process with the algorithm you have selected. Most algorithm MCPs have Input Ports panes and Output Ports panes under the Files tabs and some MCP Files tabs have additional controls. Input Ports: Allows you to select the data you want to process with the algorithm you have selected. You can use data already open or you can use the Browse button to select other input data. Browse: Opens a file selection dialog box, where you can browse for input data. You can open data directly from any Algorithm MCP using the Browse button under the Files tab. Output Ports: Lets you direct the output to a viewer, to a project file, or to both. You can save the output to the location you are already working in or you can use the Browse button to save your output to another location. Browse: Opens a file selection dialog box, where you can save your algorithm output to another location. Input Params tab: Lets you set the parameters for the algorithm input data. 169

172 Each algorithm has a unique set of parameters. Output Parameters Tab: Provides parameter controls for the output from your algorithm. Not all MCPs have an Output Parameters tab. Log tab: Displays run-time progress, including any run-time errors that occur when you run the algorithm. When you run your algorithm a progress monitor opens indicating the progress of the algorithm. When the algorithm has finished running the algorithm MCP automatically changes to show the Log tab information. Note: Some algorithms work only on a single layer, but in most cases algorithms can use most or all of the files and layers in a project. Finding help topics for all algorithms Online Help is available for all algorithms. You can find the details of what the algorithm does and what the input and output requirements are for each algorithm in the Geomatica Help. 1. From the Help menu, click General. 2. In the Geomatica Help, click the Contents tab and expand the Geomatica Algorithm Reference topic. 3. Expand the Modeler and Algorithm Librarian Reference topic. All of the algorithms for Modeler and the Algorithm Library are listed in alphabetical order. Finding help from the Algorithm Librarian dialog box 1. From the main menu, click Tools and select Algorithm Librarian. The Algorithm Librarian dialog box appears. 2. Navigate to the algorithm. 3. Right-click the algorithm and select Help. Finding help from a Module Control Panel You can find help from the Module Control Panel (MCP) of a selected algorithm. 1. From the main menu, click Tools and select Algorithm Librarian. The Algorithm Librarian dialog box appears. 2. Navigate to the algorithm and select it. 3. Click Open. The MCP for the algorithm appears. 4. Click the Help button. Working with an algorithm MCP 170

173 Algorithm MCPs provide the controls for using the algorithms in the Algorithm Library and are linked directly to any open data. If you have data loaded in Focus before using the Algorithm Library, the data in the current project is listed under the Files tab in the Input Ports pane of the algorithm MCP. You can select the input layers you want to process under the Files tab in the MCP Input Ports pane before you run the algorithm. Working with an example In the following example, the ASP algorithm is used to calculate the surface aspect of elevation data. This algorithm is found in the Spatial Analysis category under the Topographer sub-category. The ASP algorithm calculates the surface aspect or orientation angles from an elevation image. These angles represent the directions the slopes are facing. The output image contains orientation angles from 0 to 360 degrees, relative to the top of the image, with areas of zero slope assigned a single user-specified value. The SLP program calculates the surface slope. Together, the ASP and SLP programs can completely define a surface in terms of degree of slope and direction it is facing for every pixel in the image. To begin this exercise, make sure you have imagery open in the view pane and the Algorithm Library is open. Search for and open the ASP algorithm. Using the ASP algorithm When the algorithm is opened from the Algorithm Library, configure it using the ASP MCP. Setting up the input port The input port contains the elevation layer and must be a raster layer. This connection is mandatory. 1. In the ASP Module Control Panel, click the Files tab. If necessary, expand all nodes next to Input Elevation Layer to show all the available input channels. 2. Enable the check box next to channel 10 [16S] USGS Elevation Data. Setting up output ports The output port contains the aspect layer, which needs to be a raster layer. This connection is optional. 1. Expand all nodes next to the Output Aspect Layer to show Viewer and Untitled.pix as the available output options. For the current example, direct your output to both the viewer and to a.pix output file of your choice. 2. Enable the check box next to Viewer. 3. If you want to select an output file as an output port, enable the check box next to Untitled.pix. 171

174 4. Select Untitled.pix. 5. Click Untitled.pix again, type Calculate surface Aspect.pix, and press Enter. Setting up input parameters The ASP algorithm is controlled by the input parameters. Calculation of the real and projected areas depends on the proper specification of the following values: Pixel X Size (m) Specifies, in meters, the X dimension of each pixel on the ground. Pixel Y Size (m) Specifies, in meters, the Y dimension of each pixel on the ground. Elevation Step Size (m) Specifies, in meters, the elevation corresponding to each gray level. A change in the size of the Elevation Step results in a corresponding change in the gray level in the elevation image. This parameter is mandatory. Zero Slope Image Value Specifies the value that will be assigned to pixels in the output image when the intermediate slope calculation is zero. If not specified, these pixels are assigned a value of 510 because the output channel is 32-bit. 1. Click the Input Params 1 tab. 2. To change the Pixel X Size in meters, modify the value in the text field for the parameter as necessary. The default value is 30.0 meters. 3. To change the Elevation Step Size in meters, modify the value in the text field for the parameter as necessary. The default value is 1.0 meter. 4. To change the Zero Slope Image Value, modify the value in the text field for the parameter as necessary. The default value is none. Running the ASP algorithm Once you have set up the algorithm, you can run it from the ASP MCP. In the ASP Module Control Panel, click Run. Viewing the results After running the ASP algorithm, you can view information about the output layer. To view output layer information 1. Click the Maps tab in the viewer. 172

175 To view output file information 1. Click the Files tab. 2. Expand the Files node. You should see the following information listed under Rasters: 1[32R]ASP Aspect from elevation channel 10. To view execution status 1. Click the Log tab. If the algorithm ran successfully, the messages Time of execution and Execution Successful are displayed in the text area under the Log tab. To view the program results 1. Study the surface aspect of the elevation data in the viewer. If the algorithm ran successfully, the messages Time of execution and Execution Successful are displayed in the text area under the Log tab. Understanding the results The ASP algorithm uses the elevation layer in the input channel to calculate the corresponding aspect angles. The results are written to the aspect layer in the output channel, which is either the viewer or a.pix file. The correct calculation of the aspect values depends on the proper specification of the Pixel X Size and Pixel Y Size. Aspect Values: Aspect at a point is calculated as the orientation of the plane formed by the vector connecting the left and right neighbours and the vector connecting the upper and lower neighbours of the pixel or the angle between the top of the image and the projection of the normal vector of this plane onto the horizontal plane. True aspect values will always range between 0 and 360 degrees. Zero Slope Values: Areas where the slope is zero are treated as a special case and are assigned a user-specified aspect value from the Zero Slope Image Value input parameter. If this input parameter is not specified, a default value of 510 is assigned. Adding functions to the algorithm library You can create new algorithms using PACE and EASI programming and add them to the Algorithm Library, which uses definition files to describe available modules and their properties. Module definition files define the algorithms in the Algorithm Library. You can find module definition files in the etc folder, 173

176 located in the Geomatica program folders on your hard disk. Module definition files use the file name extension.def. New modules must be added to a specific package definition file in order to be accessible in the Algorithm Library. You can convert your PACE programs into Modeler modules or Focus algorithms without having to write scripts using the Geomatica Software Development Kit (SDK). The Geomatica SDK lets you create your own algorithms and add them to the Algorithm Library. Information for EASI and PACE programming languages is available in the Geomatica SDK. (See the PCI Geomatica SDK). 174

177 Chapter 5 Starting a classification session To start a supervised classification session 1. From the Map tab, right-click the layer you want to classify and click Image Classification and then click Supervised. To start an unsupervised classification session 1. From the Map tab, right-click the layer you want to classify and click Image Classification and then click Unsupervised. To start a classification session 1. In the Session Selection dialog box, click New Session if you want to begin a new classification. 2. If you want to choose a previous selection, click a session in the Sessions available box and click OK or click File to select a file. Unsupervised classification An unsupervised classification organizes image information into discrete classes of spectrally similar pixel values. To perform unsupervised classification in Focus, you work through panels and dialog boxes to configure your data files and to choose the number of classes that the computer differentiates. When you finish configuring a classification, you can run the process. Focus automatically classifies the spectral values in the image data. You can view the classification results in the view pane and as a classification report. Configuring a new classification session You can initialize a new classification session with or without data files open. 1. In the Session Configuration dialog box, type a name in the Description box. It is not necessary to identify features in the image in unsupervised classifications. Unsupervised classifiers do not use training sites; they divide the image pixels into natural groupings of statistically similar gray-level pixel values. If you want to work with more than one algorithm in the same session, use the Open command on the Select Algorithm dialog box. The Select Algorithm dialog box remains open until you click Close. 2. Adjust the Red, Green, and Blue color values to the combination you want by clicking the appropriate column for each channel. 175

178 A project can contain several classifications, each one using different sets of input channels. 3. In the Input Channels column, select channels you need for your project. 4. Select an output channel to store your classification by clicking in the Output Channel column for the channel you want to use. You can select an empty channel or you can over write an existing channel, such as a channel containing imagery of no consequence. If there are no desirable or available output channels, click Add Layer and enter values for channels in the Channels to add boxes for the appropriate channel types. Click Add. 5. Click OK. The Unsupervised Classification dialog box opens. Focus adds a classification metalayer to the Maps tree and the RGB reference image you specified opens in the view pane. Initializing unsupervised classification The Unsupervised Classification dialog box allows you to choose the type of algorithm and the parameters you want to use in the classification. 1. In the Unsupervised Classification dialog box, enable one of the following algorithm options: K-Means Fuzzy K-Means IsoData 2. In the algorithm Parameters table, click in the appropriate box in the Values column and enter the criteria that you want in the classification. 3. In the Classifications Options area, enable any of the following check boxes: Show report Save signatures Create PCT 4. Choose a training site option from the Use bitmap as mask list box. If you choose an option other than None, choose a mask region from the Classify region list box. 5. Click OK. Note: It is recommended that you use many clusters (for example, the full 255 allowed in an 8U channel) and then perform aggregation to get the actual number of information classes you want. Note: To view the unclassified image, drag the unclassified image file layer to the top of the Maps tree above the Classification MetaLayer. The original image appears in the view pane. Reading a classification report The classification report indicates the distribution of pixel values across the number of classes set in the Unsupervised Classification dialog box, a date stamp, and the file path for the classified imagery. The classification algorithm is also listed with the input channels and the channel in the data file where the results are stored. 176

179 The report also lists the number of clusters created by the classification with the details for each cluster. Clusters are groups of pixels with similar spectral properties. The report tells you how many pixels make up each cluster, the mean brightness value, and the standard deviation for each of the input image channels. Supervised classification In supervised classification, you must rely on your own pattern recognition skills and knowledge of the data in determining the statistical criteria (signatures) for data classification. To select reliable training sites, you should have some information, either spatial or spectral, about the pixels that you want to classify. Carrying out effective supervised classification may take practice. It requires you to develop the ability to recognize your target features and visual patterns in your image data. The process can be repetitive, depending on how quickly you can produce satisfactory results. The diagram below shows the task flow of the Supervised Classification process. The location of a specific characteristic, such as a land cover type, may be known through reports on ground truth. Ground truthing refers to the acquisition of knowledge about the study area from field-work analysis, aerial photography, or personal experience. Ground truth data is considered to be the most accurate (true) data available about the area you want to study and should be collected at the same time as the remotely-sensed data, so that the data corresponds as much as possible. Sometimes, ground truth data may not be accurate, due to errors, inaccuracies, and human error. Global positioning system (GPS) receivers are useful in conducting better ground truth studies and collecting training sites. The supervised classification process 177

180 same files without re-initializing a new session each time. Focus automatically assigns red, green, and blue (RGB) values to the first three channels. You can select the exact combination of channels by assigning the color channels that define the reference image for collecting your training sites and for doing any post-classification analysis. 1. From the Analysis menu, click Image Classification and then click Supervised. 2. In the File Selector dialog box, locate and select an image file you want to classify. 3. Click Open. 4. In the Session Selection dialog box, click New Session. 5. In the Session Configuration dialog box, type a name for your classification in the Description box. Note: When naming classification sessions, enter a name in the Description text field that will distinguish your current classification from others you create. The Supervised Classification Process Initializing a supervised classification Like unsupervised classification, supervised classification is initialized as a session. The initialization procedure also helps you manage subsequent classifications on the Specifying the reference image Focus automatically assigns red, green, and blue (RGB) values to the first three channels. You can assign color channels to define the reference image that will be used during training site data collection and in any subsequent post-classification analysis. Because supervised classification requires you to rely on your own pattern-recognition skills and a prior knowledge of the scene, you may need to visually identify your 178

181 training areas from familiar colors in the ground cover. In such cases, you must change the RGB values to match the TM bands in the image data to produce a true color-reference image. The task of collecting training areas is made easier by working with a reference image that simulates normal or true color. However, personal preferences often guide the choice of band - color combinations for interpretive purposes. In some applications, you must use a different combination of color channels; for example, channels that fall outside the visible color range. Whatever your preference, it is unlikely that the default color assignment offered in the Session Configuration dialog box will coincide with your choice. You can reset the color assignments by clicking the corresponding cell of the desired channel in each of the Red, Green, and Blue columns. You can rearrange the color channels to see a true color rendition of the image in the view pane. Specifying the input channels Spectral classes are groups of pixels that have uniform or nearly similar brightness values in the different spectral channels of the data. The spectral attributes of the classes used to train the computer are determined by the spectral channels that you choose to include in the training and classification process. You can use Focus to match the information classes you create with a spectral class in the image data. Note: To determine the optimal combination of bands for spectral discrimination in your training sites you can use the channel select (CHNSEL) algorithm in the Algorithm Librarian. Once you have set the RGB values for true color, you can define the spectral attributes for the ground cover you want to classify. You must choose a set of data channels that will define the spectral attributes or signatures in your classes. To select the input data set 1. In the Session Configuration dialog box, click in a cell next to a spectral channel in the Input Channels column. A check mark indicates that the channel is selected. 2. Select a channel for collecting your training sites. Note: You can use an empty channel, a channel where the contents can be over written or you can add a new working channel. You can add empty channels to the Session Configuration list and the Files tree. To add a new channel 1. Click the Files tab and right-click the image file folder. 2. Click New and then click Raster Layer. 3. In the Add Image Channels dialog box, choose the 179

182 bit depth and number of new channels you want to add. 4. Click Add. If you want to close the Add Image Channels dialog box, click Close. Once you have added channels, you must select them in the Session Configuration dialog box so that they receive the classification output. If you have not added empty channels, you must select channels that you intend to overwrite. To select the output channel 1. In the Output Channel column, click a channel. 2. Click OK. The details of the configuration setup are now shown in the Maps tree and the reference image opens in the view pane. The Training Site Editor dialog box opens with a blank training channel. The training channel is now write-enabled and ready for you to begin collecting your training sites. Training sites and ground cover You designate training sites based on samples of different surface cover types in your imagery by drawing colored regions or areas over the parts of the image that are likely to be the information classes you want to extract. You cannot know for certain what the actual ground cover in an image is by referencing only the image; therefore, samples (training sites) must be based on familiarity with the geographical region and knowledge of the actual surface cover types shown in the image. Training sites are areas in an image that are representative of each of the land cover classes that you want to define. Focus examines the pixel values within the training sites in order to compile a statistical signature for each training site class. The training signatures serve as the interpretation key for each pixel in the image. All pixels in the image are compared to the signatures and then classified. You can use the Training Site Editor to create training sites to supervise the classification. 1. From the Training Site Editor, click Class and then click New. 2. Double-click Class-01 in the Name column and type a name for the training site. 3. Click one of the following: Drawing a class training site Once you have created a class with the Training Site Editor, you can draw training sites over the reference image in the view pane. 180

183 1. In the Maps tree, select the Training areas layer in the Classification MetaLayer. 2. On the Editing toolbar, click the New Shapes arrow and choose Polygon. 3. Click the reference image within the bounds of the subject area where you want to start the training area outline. 4. Trace the outline of the polygon by clicking at the end of each line segment. 5. To complete the polygon, double-click near the first point in the training site. 6. Identify similar areas from the imagery that match your first polygon. The more areas you identify as training sites, the higher the accuracy of the classification. Note: Overlapping your training area boundaries reduces the reliability of your training sites. Making corrections 1. On the Editing toolbar, click the Raster Erase arrow and choose an erase option. 2. Trace over the training site you want to remove from the image. 3. Double-click to erase. (See About the Erase Settings dialog box on page 181 ) About the Erase Settings dialog box The Erase Settings dialog box lets you choose a fill polygon option and adjust the line width of the Raster Erase tool. Fill Polygon: Removes the inside of a polygon when using the Erase Polygon option. Line Width: Lets you enter a line width, in pixels, for the Raster Erase tool. Changing training site colors You can change the color of your training sites. Focus automatically assigns colors to new training sites. Your first class may be green and your second class may be blue when they are drawn in the view pane. You can change the color of the class sites to any color. 1. In the Maps tree, right-click the Classification MetaLayer and click Open training sites. 2. In the Training Site Editor, click a color. 3. In the color dialog box, make any changes to the color. 4. Choose a color model from the Model list box and make any changes to the color channels in the appropriate spin boxes. 5. Click OK. Importing training sites 181

184 You can also import vectors, bitmaps, or signatures and use them as training sites. The Import Vectors dialog box uses rasterized vector polygons to define training sites. 1. In the Training Site Editor, right-click a class row. 2. Click Import and then clickvector(s). Importing vectors The Import Vectors dialog box lets you Import vector segments Choose which vector layer is to be rasterized Choose how a vector layer is rasterized Vectors Table The import table lists all the vector segments that are present in the selected file. There are five columns: Segment: Lists the number associated with each vector segment in the selected database. Interior Points: Identifies which vector segments contain the point information that will be used to define the rasterized value of the polygons. You can select more than one interior point segment. Polygon Boundary: Indicates which vector segments contain the polygon information that will define the boundaries of the rasterized polygons. You should select one or more of these segments. Field: For each selected vector segment, this choice determines which field value is used to grid the polygons. Numeric attributes are displayed. Some vector segments may contain different attributes. Description: Displays the descriptions associated with each vector segment. Supported Vector Formats When importing vectors into a training site editing session, the following vector types are supported: ALL_POLYGONS GDBLTopoAreas This information can be found in the MetaData tab for the vector layer properties. 1. In the Import Vectors dialog, choose the file containing the vectors you want to import from the File list box. 2. If the file you want is not listed, click Browse, locate and select the file you want in the File Selector dialog box, and click Open. 3. Click in the Interior Points column next to the rasterized value you want to define. A check mark indicates the segment has been selected and will override any entry in the Field column. 4. Click in the Polygon Boundary column next to the rasterized value you want to define. A check mark indicates the segment has been selected. 5. Click in the Field column for a segment and choose a rasterization value to change the field used for rasterization. This column is ignored if the Interior Points column has been enabled. 182

185 6. Click Rasterize. Importing a vector does not overwrite existing classes. The polygons are added to the image where no classes exist. This occurs for pixels with a value of zero. Opening the Import Bitmaps dialog box The Import Bitmaps dialog box uses existing bitmaps to define training sites. In the Training Site Editor, right-click in a row and click Import and then click Bitmap(s). About the Import Bitmaps dialog box The Import Bitmaps dialog box lets you: Create a new class with the specified bitmap as its training site Change a class training site that you choose in the Training Site Editor Replace the class training site selected in the Training Site Editor By default, imported bitmaps do not overwrite existing training sites. To overwrite training sites, enable the Overwrite existing training areas check box. Importing a specified bitmap as its training site 1. Enable one of the following options: New class: creates a new class with the specified bitmap as its training site Current: augments the training site of an existing class 2. Select a bitmap from the Bitmaps available list. If you want to overwrite training sites, enable the Overwrite existing training areas check box. 3. Click OK. Importing signatures from the training site editor The Import Signature dialog box displays a list of the signatures that are compatible with the currently selected class. Compatibility is determined by the combination of input channels used to generate the signature. Compatible signatures must have the exact same set of input channels as those being used for the current classification. Instead of calculating a signature segment from training sites, you can import an existing signature from the Import Signature dialog box. 1. In the Training Site Editor table, right-click a class row and click Import and then click Signature. 2. In the Import Signature dialog box, select the 183

186 signature you want to import. 3. Click OK. Filling polygons using the Raster Seeding function When your training sites need to be irregular shapes or polygons made of homogeneous pixel groups, you can use the Raster Seeding function to grow and fill a region of similar pixels. You can vary the tolerance of the growth in the Raster Seeding dialog box to slowly adjust the size of the grown region. Higher tolerance settings create large growth regions and lower tolerance settings create smaller growth regions. You can use the Raster Seeding function to grow regions of various sizes. The Raster Seeding dialog box opens from the New Shapes list on the Editing toolbar. (See About the Raster Seeding dialog box on page 184 ) About the Raster Seeding dialog box The Raster Seeding dialog box allows you to select an input file and layer, view the name and location of the input files, and set the properties of the raster seeding output. Input Layer The Input Layer area lets you read the location of the input data and choose the layer on which to perform the seeding operation. Selection Criteria (Layer): Provides a list of files and lets you choose the input data for a seeding operation. Layers: Opens the Select Seeding Layers dialog box. (See Filling a polygon on page 185 ) Selection Layers: Reports the name and location of your input data files. Output Layer The Output Layer area shows the name and location of the output files. Selected Layer: Reports the name and location of the selected layers. Properties The Properties area lets you set the Input Pixel Value tolerances and choose from either a four-connect or an eight-connect option. Input Pixel Value Tolerance: Lets you enter a pixel value as a seeding tolerance and choose an X value from a list. 184

187 Neighborhood: Lets you choose either a four-connect or an eight-connect option to set the kernel size for the raster seeding operation. Filling a polygon The Select Seeding Layers dialog box lists all of the available input layers and allows you to select the layers you want to include in the seeding operation. Clear: Clears all selected layers from the list. Select All: Lets you select all of the listed layers. Selected Layers: Reports the layers you have selected. 1. In the view pane, click a polygon. 2. On the Editing toolbar, click the New Shapes arrow and choose Raster Seeding. 3. In the Raster Seeding dialog box, select the layers with which you want to fill the polygon. 4. Click OK. Merging classes The Merge command combines several classes into one. Merge affects the portion that is opened and the entire training channel. 1. From the Training Site Editor, click Class and then click Merge. 2. In the Merge Classes dialog box, select the classes you want to merge from the Source list. If you want to select multiple classes, hold down the Ctrl or Shift key and click the classes you want to merge. 3. Select a destination class in the Destination list. 4. Click Merge. Analyzing training sites Often during classification, unique spectral classes appear that do not correspond to any of the classes you want to use. In other cases, a broad information class may contain a number of spectral sub-classes with unique variations. This can be caused by a mixture of ground cover types appearing in the image at the time it was recorded, or by shadows and variations in scene illumination. Focus offers several methods for insuring that your training sites are both representative and complete.you can work with training site data using the Training Site Editor, the Signature Statistics dialog box, and the Scatter Plot dialog box. You can view and test the reliability of your training sites 185

188 by creating a histogram in the Class Histogram Display dialog box. The histogram shows the frequency of training site pixels as a percentage of the number of pixels in your training sites. A histogram should have a uni-modal shape displaying a single peak. A multi-modal histogram indicates the likelihood that the training sites for that class are not pure, but contain more than one distinct land-cover class. From the Training Site Editor, right-click in a class and click Histogram. In the Class Histogram Display dialog box, the X-axis in the histogram represents the gray-level value for the image channel with a range of 0 to 255. The Y-axis shows the frequency count as a percentage of the total count of pixels in the training area corresponding to the gray value. Testing signature separability Signature separability is calculated as the statistical difference between pairs of spectral signatures. You can use the Signature Separability dialog box to monitor the quality of your training sites. Divergence is shown as both Bhattacharrya Distance and Transformed Divergence, with the Bhattacharrya Distance as the default calculation. Both Bhattacharrya Distance and Transformed Divergence are shown as real values between zero and two. A zero indicates complete overlap between the signatures of two classes; two indicates a complete separation between the two classes. These measurements are monotonically related to classification accuracies. Note: Higher separability values indicate a good classification result From the Training Site Editor, click Tools and then click Signature Separability. Testing separability with a scatter plot You can use the Scatter Plot dialog box to show elliptical graphs for all training sites. A class ellipse shows the maximum likelihood equiprobability contour defined by the class threshold value entered for the mean. Threshold is a relative measure used to control the radius of the hyperellipse for each class. By changing the threshold values, you can reduce the chances of pixels being classified into more than one class. Bias is a value from 0 to one, where higher values weigh one class in favour of another. It can also be used to resolve overlap between classes. You can use both of these measurements to test the training site separability. 186

189 Creating a scatter plot You can use the Plot Ellipses options in the Class List Table to assess the separability of your spectral classes and to refine and edit your training sites. A scatter plot should display an ellipse for each of the training classes. When there is overlap in several of the band combinations, you must adjust the threshold values. 1. From the Training Site Editor, click Tools and then click Scatter Plot. 2. In the Scatter Plot dialog box, click in the Plot Ellipses column for each class that you want to include in the scatter plot. A check mark indicates a class has been selected. If you want to magnify a section of the graph, right-click on the area in the graph and click Zoom In. Adjusting scatter plot threshold values 1. From the Training Site Editor, double-click the Threshold column for the class you want to adjust and type a new value. The class ellipse adjusts automatically to show the change in the threshold value. 2. From the Tools menu, click Classification Preview and click one of the following: Maximum Likelihood Maximum Likelihood with NULL class Parallelepiped Parallelepiped with MLC Tiebreaker Maximum Distance Show Training Sites 3. Click Save&Close. Altering the view range for the X and Y axes You can use the Graph Controls option in the Scatter Plot dialog box to alter the view range for the X and Y axes. 1. In the Scatter Plot dialog box, click Graph Controls. 2. Enter values in the Min and Max boxes in the X View Range and Y View Range areas. 3. Click Close. Exporting the scatter plot file 1. In the Scatter Plot dialog box, click Graph Controls. 2. Click File in the Export area. 3. Locate and select a file in the File Selector dialog box. The default file format is PCIDSK. TIFF, BMP, and PostScript formats are also available. 4. Click Save. 5. Click Export in the Graph Controls dialog box. Displaying the color scale legend 187

190 You can display the color scale legend on the side of the scatter plot in the Scatter Plot dialog box. 1. In the Scatter Plot dialog box, click Graph Controls. 2. Enable the Show legend check box. Printing the scatter plot You can print the displayed histogram or its zoomed version. 1. In the Scatter Plot dialog box, click Graph Controls. 2. In the Options section, enable the Fix aspect ratio check box, if required. 3. In the Background list box, select a background color for the scatter plot. The selected color appears behind the scatter plot in the Scatter Plot dialog box. 4. Click Print and specify printer settings. 5. Click Print. Previewing the classification You can preview a classification result using one of the previewcommands in the Training Site Editor or from the Utilities option from the classification metalayer in the Maps tree. The preview commands show how the input channels will be classified using the training sites and class parameters contained in the training channel. You can preview with the following commands: Maximum Likelihood Maximum Likelihood with NULL class Parallelepiped Parallelepiped with MLC Tiebreaker. Minimum Distance Show Training Sites Setting the Maximum Likelihood classification preview Ensure that you have selected a session that has been configured. 1. In the control pane, click the Maps tab. 2. Right-click the Classification MetaLayer and click Open training sites. 3. In the Training Site Editor, click Tools and then click Classification Preview and then click Maximum Likelihood. Removing the preview classification from the metalayer 1. In the control pane, click the Maps tab. 2. Right-click the Classification Metalayer and click Open training sites. Creating a separability report 188

191 You can create reports for a signature separability and save them to data files. 1. Click Save Report. 2. In the Save Separability Report dialog box, enter a file name for the separability report in the File box. 3. Click Save. Saving the separability report to an existing file 1. Click Save Report. 2. In the Save Separability Report dialog box, click Browse. 3. In the File Selector dialog box, locate and select the file. 4. Click Open. 5. In the Save Separability Report dialog box, click Save. Running a supervised classification When you have analysed your training sites and tested their separability, you are ready to run a supervised classification. 1. In the Maps tree, right-click Classification MetaLayer and click Run Classification. 2. In the Supervised Classification dialog box, enable one of the following options in the Algorithm area Parallelepiped: forces every pixel in the image to belong to one of the user-defined class types. If you choose this option and want to include Maximum Likelihood as a tie breaker, enable the With Maximum Likelihood as tie breaker check box. Minimum Distance: forces every pixel in the image to belong to one of the user-defined class types. Maximum Likelihood: allows a null-class parameter option. In some cases, you want to extract classes, but there are many more land cover classes represented in the imagery. Therefore, you want a proportion of pixels left unclassified, or null. 3. In the Classification Options area, enable any of the following check boxes: Show Report: generates a report of the classification data. Save signatures Create PCT: compares your classification with another classification. 4. Click OK. The report should show a high overall training site accuracy. The information from each pixel in the training areas is compared to the information determined by the classifier algorithm. The overall accuracy represents the percentage of training-area pixels that were correctly classified. Your training areas are ideal examples of the classes. Testing accuracy with signature statistics Focus lets you test the accuracy of a training site collection.the Signature Statistics dialog box displays the number of samples in the training area, indicating whether you have collected enough pixels to accurately 189

192 represent the land cover. You can compare the statistics for several classes at the same time. 1. From the Training Site Editor, right-click a class and click Statistics. 2. In the Signature Statistics dialog box, click a class in the table to display its statistics. Note: Similarities cause errors during classification. Consider removing a channel from the list of inputs if you are not getting good results. Viewing signature statistics The Signature Statistics dialog box displays a table of the classes included in the currently selected image. For each class, the following columns are included: ID Value Name Color Threshold Bias Imported signature status Description General Report The General report lists the mean and standard deviation for each input channel under the class's training area mask. Click the General tab. Viewing a matrix report The Matrices report lists the following matrices for the class signature: Class Correlation matrix Class Co-variance matrix Inverse Co-variance matrix Triangular Inverse Co-variance matrix Click the Matrices tab. Comparing signature statistics You can open a multiple Signature Statistics dialog boxes to view and compare the statistics of several different signatures at the same time. From the Signature Statistics dialog box, click New Panel. Editing Class Signatures You can also edit any of the cells in the class table. Saving the signature statistics report You can save both the general and matrices statistics for all of the classes to a text file. 1. In the Signature Statistics dialog box, click Save Report. The Save Statistics Report dialog box appears. 190

193 2. Specify a file name and its directory path. 3. Click OK. Post-classification editing In most cases, a classifier algorithm does not produce ideal results. There are often occurrences of single-pixel misclassification. A field may contain a few pixels of another class or there may be image data that falls outside training sites that affects the classification results. Class editing corrects errors by combining several classes. Improving classification results To improve a classification, first assess the accuracy of your results. The accuracy of a classification is measured against a standard that is assumed to be correct. The classification accuracy increases as it approaches the standard. Once you have assessed the classification accuracy, you can combine classes through a process known as aggregation. Combining classes creates a new aggregate class. A maximum of 255 classes can be reassigned in a single session. Aggregation is often performed on the results of an unsupervised classification. A common approach in unsupervised classification is to generate as many cluster classes as possible. With the benefit of reference data or first-hand knowledge of a scene, you can aggregate the spectral clusters into meaningful thematic classes. Initialize post-classification editing You can combine several classes once you have edited your classification. Like the aggregation process, class editing combines several classes; however, instead of combining classes throughout an image, you can combine the classes for all pixels under a bitmap mask. 1. In the Maps tree, right-click Classification MetaLayer and click Post-classification Analysis and then click Class Editing. 2. In the Class Editing dialog box, click Image and then click Select Classified Image. 3. In the Select Classified Image dialog box, choose the output channel you selected when you initialized the classification from the Channels available list. 4. Click OK. 5. In the Class Editing dialog box, click Image and then click Select Reference Image. 6. In the Load Reference Image list, locate and select the Red, Green, and Blue channels. You must use the same reference image to perform class editing. As you select a channel, its number is added to the R, G, and B boxes. 7. Click OK. Once you have selected a reference image you can prepare to draw your bitmap mask. Setting up a bitmap mask 191

194 1. In the Class Editing dialog box, click Mask and then click Create Mask from new Bitmap. 2. Ensure the Mask visible check box is enabled. 3. In the Visible Image area, enable the Classified option. 4. In the Maps tree, click the bitmap layer. 5. On the Zoom toolbar, click the Zoom to 1:1 Image Resolution button. Note: Images must be displayed at 1:1 or higher to draw a bitmap mask over the view pane. The drawing tools are not available when images are zoomed to overview size. Opening a bitmap mask The Load Mask from Bitmap command produces a mask with a bitmap that had been previously created. This is useful if you want to replace the class of a particular training site with a new bitmap mask. 1. From the Class Editing dialog box, click Mask and then click Load Mask from Bitmap. 2. In the Load Mask from Bitmap dialog box, select a bitmap segment in the Bitmap segments available list. 3. Click OK. Saving a bitmap mask You can save the active mask as a bitmap. 1. From the Class Editing dialog box, click Mask and then click Save Mask to Bitmap. 2. In the Save Mask to Bitmap dialog box, select a bitmap segment in the Bitmap segments available list. 3. Click OK. Masking an image area The masked area combines classes. You can select a region over the entire file to combine all of the classes in the image. Masking an image area is similar to creating a training site. You can mask over a part of the image. 1. In the Maps tree, select the new bitmap layer below the Classification MetaLayer. 2. On the Editing toolbar, click the New Shapes arrow and choose Polygon. 3. In the view pane, draw a mask over the part of the image you want to edit. 4. In the Class Editing dialog box, select a class in the Source Classes area. If you want to select all classes, click Select All. 5. Click the Merge Classes. 6. In the View Controls area of the Class Editing dialog box, disable the Mask visible check box. If you want to use more than one mask to cover all of the image areas you want to edit, repeat the procedure. Opening an aggregation session 192

195 Aggregation is the process of combining classes in order to create a new aggregate class. A maximum of 255 classes can be reassigned in a single session. Aggregation is often performed on the results of an unsupervised classification. A common approach in unsupervised classification is to generate as many cluster classes as possible. With the benefit of reference data or first-hand knowledge of the scene, the analyst aggregates the spectral clusters into meaningful thematic classes. 1. From the Analysis menu, click Image Classification and then click Post Classification Analysis and then click Aggregation. 2. In the File Selector dialog box, locate and select a file. 3. Click Open. Opening the Aggregate dialog box in an unsupervised session In the Maps tree, right-click Classification MetaLayer and click Post-classification Analysis and then click Aggregation. Setting up an aggregation Channel Setup Before you can perform an aggregation, you must specify the database channels that serve as the input and output channels. This is done using the Channel Setup dialog box. Input Channel This is the channel you want to aggregate and is typically the result of an unsupervised classification. Output Channel This is an empty channel. You store the results of the aggregation in this channel. 1. In the Channel Setup dialog box, select an unsupervised classification channel from the Channels available list. 2. Select an empty channel or an unfinished aggregation result from the Output list. 3. Click OK. Setting up a new aggregate class Image classifiers do not always provide the desired level of accuracy. As a result, a clean-up is often necessary after a classification. Aggregation is one of the four post-classification clean-up methods. There are three main areas in the Aggregate dialog box. View Controls Use this area of the dialog box to choose different ways to view the classes and aggregates. 193

196 Normal mode Displays the aggregate classes along with the original, as yet unassigned, classes. Input classes Displays all the original input classes. Current classes Displays the classes that are currently selected in the Input Classes list. Unassigned classes Displays only the unassigned classes. Input classes that have been assigned to an aggregate will be blacked out. Aggregate classes Displays all the current aggregates. Current aggregate classes Displays the aggregates that are currently selected in the Aggregate Classes list. Highlight color Lets you choose a color for the class. Input Classes This table lists all of the classes in the selected input channel. Use this table to locate and select the set of classes to include in each of the aggregate classes. You can select multiple classes by holding down Shift or Ctrl while clicking a selection. There are several tools available to assist you in the selection process: Select Class at Cursor Locates the class at the current cursor location within the view pane. Highlight Classes Displays the selected input classes in the chosen highlight color, as selected in the View Controls area. PCT Changes the current pseudo-color table. Aggregate Classes This table contains a list of all the aggregate classes. In addition, there are four tools available to assist you: New Creates a new aggregate class. Delete 194

197 Removes an aggregate class from the list. Class Initialization Save Saves all the details of the aggregation session to a text file. The following example of a text file that describes three aggregate classes: 1 Water Water class 10,20 2 Crop Crops 3 Other Class Water class 40 To help you to identify and locate classes, use the Highlight color feature. The selected class(es) assume the highlight color. Use the Highlight color palette to change the color used for highlighting. 1. In the Aggregate Classes area, click New. 2. Double-click the Name column for the new class and type a name. 3. Click the Color column for the new class and choose a color. The Add and Remove tasks are only active after selections are made in both lists. Creating an aggregate from a set of input classes 1. Select a row containing the class you want to add from the Input Classes area. If you want to select multiple rows, hold down the Ctrl or Shift key while selecting rows. 2. Select the row containing the aggregate class that is to receive the input class. 3. Click Add. 4. Repeat steps 1 to 3 until the input classes are assigned to the appropriate aggregate classes. 5. Click Apply to Output Channel. Changing the input and output channel assignments 1. From the Aggregate dialog box, click Setup. 2. In the Channel Setup dialog box, select a new input channel from the Channels available list. 3. Select an empty channel from the Output list. 4. Click OK. Assigning a new PCT to the current session Use the Generate or Import PCT dialog box to change the pseudo-color table assigned to the current aggregate session. You assign a new PCT in two ways: Generate PCT: Creates a PCT that attempts to simulate a reference RGB image. Duplicating the look of an RGB image may assist you in identifying and locating areas within the image to be aggregated. Import PCT: Imports an existing PCT. 195

198 Generating a PCT 1. From the Aggregate dialog box, click PCT in the Input Classes area. 2. In the PCT dialog box, click the Generate PCT tab. 3. For each of the red, green, or blue channel designations, select a channel from the Channels available list. 4. Click OK. Importing a PCT 1. From the Aggregate dialog box, click PCT in the Input Classes area. 2. In the PCT dialog box, click the Import PCT tab. 3. Click File. 4. In the File Selector dialog box, locate and select the file containing the PCT segment you want to import, and click Open. 5. Click Open. 6. n the PCT dialog box, select a segment in the list. 7. Click OK. Saving the aggregate session Aggregation is usually a lengthy process, especially if you want to test and compare several different aggregation scenarios. It is recommended that you use the Save Aggregate Session feature periodically to save your work. You must save the details of your aggregate session in order to: Save intermediate results. Generate different aggregation scenarios. 1. From the Aggregate dialog box, click Save. 2. In the Save Aggregate Session dialog box, click File. 3. In the File Selector dialog box, select a destination folder. 4. Type a file name in the File name list box. 5. Choose a file extension from the Files of type list box. 6. Click Open. 7. Click Accept. Aggregate sessions are saved as.txt files by default. The following example shows a typical line in a saved aggregate text file. 1 Rural , 4 This aggregate line shows the following information: Class value: 1 Class name: Rural RGB color: Red-0 Green-204 Blue-0 Description: None Input class codes: Classes 3 and 4 were combined to create the aggregate. Starting an aggregate session Once an aggregate session file is saved, you can open it using the Load command in the Aggregate Classes area. 1. From the Aggregate dialog box, click Class Initialization in the Aggregate Classes area. 196

199 2. In the Class Initialization dialog box, click the Text File tab. 3. Click Text File. 4. In the File Selector dialog box, locate and select the aggregate text file, and click Open. If you want to overwrite the aggregate class, enable the Overwrite existing classes check box. 5. Click OK. Importing other classes The Load command and the Class Initialization dialog box can be used to: Import other channels from the same or a different file. In this way, you can add new classes to the aggregates list, which may include classes from other classification results that you want to include in the present classification. Initialize a new set of classes for an aggregation session. You import entries for the Input Classes table from either a classification channel or a.txt file. 1. From the Aggregate dialog box, click Class Initialization in the Aggregate Classes area. 2. In the Class Initialization dialog box, click the Channel tab. 3. Click File. 4. In the File Selector dialog box, locate and select the file containing the channel with the classes you want to import, and click Open. 5. Select a classification channel from the Channels available list. You can edit any of the following fields in the table for the selected channel: 6. Value 7. Name 8. Color 9. Description If you want to replace all current classes, enable the Overwrite existing classes check box. 10. Click OK. Setting up for class labelling Class editing and aggregation both honour any session information present, but work equally well without it. All other tasks including class labelling and accuracy assessment need an open session. To open a session 1. From the Analysis menu, click Image Classification and then click Post Classification Analysis and then click Class Labelling. 2. From the File Selector dialog box, locate and select a file, and click Open. To open the Class Labelling dialog box in an open session 1. From the Maps tree, right-click Classification MetaLayer and click Post-classification Analysis and then click Class Labelling. 197

200 To set up for labelling 1. From the Channel Setup dialog box, select a classified channel from the Channels available list. 2. Click OK. About the Class Labelling dialog box The Class Labelling dialog box lets you examine and modify the characteristics of any class within a thematic channel. You can change the class information such as the value, name, color, or description, but the image data is not altered. You can create a new class in the table of the Class Labelling dialog box. For each new class, Focus generates an ID, value, class name, and color. File and Channel: The file name and channel are listed at the top of the dialog box. Class Table: All of the classes for the selected channel are listed in a class table. For each class, the following is reported: Value Name Color Description Unsupervised: Class labelling is normally done after an unsupervised classification, since the class values, names, and colors have not been previously assigned. Supervised: You can use the Class Labelling dialog box after a supervised classification to: Re-label characteristics that were labelled incorrectly in the Training Site Editor before classification. Label items that were not labelled prior to the classification step for whatever reason. Add a level of transparency. Add a more detailed description. You can change any of the items in the table. To keep a change, click Save. To change a class name 1. Double-click class name you want to edit. 2. Type a name and press Enter. To change a class color 1. Click a color in the Color column for a class. 2. In the Color dialog box, choose a color from the Basic Colors palette. 3. Adjust the color as appropriate. 4. Click OK. 198

201 To change or add a class description 1. Click in the Description column for a class. 2. Type a description as appropriate. To create a new class in the table 1. In the Class Labelling dialog box, click New. The new class is displayed as the last entry in the table. To delete a class 1. In the Class Labelling dialog box, select a class. 2. Click Delete. To initialize a class 1. In the Class Labelling dialog box, select a class. 2. Click Class Initialization. Class Initialization dialog box appears. To save changes 1. Click Save. Initializing classes from a classification channel Initializing a new set of classes for a class labelling session is done using the Class Initialization dialog box. You can import entries for the class table from a classification channel. 1. From the Class Initialization dialog box, click the Channel tab. 2. Click File. 3. In the File Selector dialog box, locate and select the file containing the channel whose classes you want to import, and click Open. 4. In the Class Initialization dialog box, select a classification channel in the Channels available list. If you want to replace all current classes, enable the Overwrite existing classes check box. 5. Click OK. Initializing classes from a text file Initializing a new set of classes for a class labelling session is done using the Class Initialization dialog box. You can import entries for the class table from a text file. Text file format Class or aggregate details are stored as.txt files. To import this information, it must conform to a single recognizable format. The file is limited to one class per line and has seven fields delimited by a character: Value Name Red Green Blue Desc AssociatedDesc 199

202 Value is an integer representing the class code. Name is a character string containing the class name. Red is a number between depicting the red component of the RGB color. Green is a number between representing the green component of the RGB color. Blue is a number between representing the blue component of the RGB color. Desc is a character string that provides a description for the class. AssociatedDesc is only used in an Aggregation session. It contains the description of the original input classes that are associated with the aggregate. The following is an example of a text file that contains three classes: 1 Water Water class 2 Crop Crops 3 Other Water class 1. From the Class Initialization dialog box, click the Text File tab. 2. Click Text File. 3. In the File Selector dialog box, locate and select the file containing the classes you want to import, and click Open. If you want to replace all current classes, enable the Overwrite existing classes check box. 4. Click OK. Launching the Accuracy Assessment dialog box Accuracy assessments determine the correctness of the classified image, which is based on pixel groupings. Accuracy is a measure of the agreement between a standard that is assumed to be correct and an image classification of unknown quality. If the image classification corresponds closely with the standard, it is said to be accurate. To launch the Accuracy Assessment dialog box 1. From the Analysis menu, click Image Classification and then click Post Classification Analysis and then click Accuracy Assessment. 2. In the File Selector dialog box, locate and select the file containing the classified channel you want to check for accuracy, and click Open. To open the Accuracy Assessment dialog box during classification 1. From the Maps tree, right-click Classification MetaLayer and click Post-classification Analysis and then click Accuracy Assessment. Using the Accuracy Assessment dialog box The Accuracy Assessment dialog box contains three 200

203 areas: Operations Select Classified Image Load Reference Image Generate Random Sample Samples from Vectors Accuracy Report Clear Sample List Assign Reference Class to Sample This area contains a table listing all the categories in the selected classified image. The assignment of class and name values to the test pixels is based upon the entries in this table. Random Sample List This area contains an information table for all the randomly generated test pixels. Selecting a classified image 1. From the Accuracy Assessment dialog box, click Select Classified Image. 2. In the Select Classified Image dialog box, select a supervised classification channel from the Channels available list. 3. Click OK. Selecting a reference image 1. From the Accuracy Assessment dialog box, click Load Reference Image. 2. In the Load Reference Image dialog box, select either one or three image channels from the Channels available list. If you choose only one channel, select a PCT segment from the PCTs availablelist. 3. Click OK. Generating a random sample The Generate Random Sample dialog box generates a set of random test pixel locations within the classified image. This dialog box consists of two areas: Number of Samples Provides a spin box for specifying the number of random samples to generate. Options Sets the following sampling control options: Stratify Samples to Class Percentages check box Enable this check box to randomly choose the number of samples from each class that are proportional to the percentage of the image occupied by each class. In other words, larger classes contain more samples than smaller classes. 201

204 Include only existing classes check box Enable this check box to generate random samples only for classes in the reference class list. 1. From the Accuracy Assessment dialog box, click Generate Random Sample. 2. In the Generate Random Sample dialog box, enter a value for the number of sample points from the Number of samples spin box. If you want to randomly choose the number of samples from each class that are proportional to the percentage of the image occupied by each class, enable the Stratify Samples to class percentages check box. If you want to generate random samples only for classes in the reference class list, enable the Include only existing classes check box. 3. Click OK. Assigning a reference class to a sample 1. From the Accuracy Assessment dialog box, select the first sample in the Random Sample List. The cursor automatically moves to the sample location in the view pane. Compare this location to the reference class table. 2. Select the class in the Assign Reference Class to Sample table to which you think the random sample belongs. 3. Click Transfer. Opening samples from a vector segment Imports your own random test points from a vector segment. The random pixel locations are added to the existing list of sample points displayed in the Random Sample List. In this way, you can merge samples from several sources. 1. From the Accuracy Assessment dialog box, click Samples from Vectors. 2. In the Samples from Vectors dialog box, select a vector segment from the Vector segments available list. 3. Select a reference attribute from the Reference attributes list. 4. Select a class attribute from the Class Attribute list. 5. Click OK. Launching the Accuracy Report dialog box You can use the Accuracy Report dialog box once reference classes are assigned to the random samples. Accuracy is determined by comparing the assigned reference value for each test pixel to the category in the classification image. To generate a report, it is not necessary to assign a reference class to every random sample; however, a classified image must be previously selected. From the Accuracy Assessment dialog box, click Accuracy Report. 202

205 The Accuracy Report dialog box creates three types of accuracy reports: Sample Report Listing: Shows which samples are correctly classified. Error (Confusion) Matrix: Displays the results of the accuracy assessment process. Reference data listed in the columns of the matrix represents the number of correctly classified samples. Accuracy Statistics: Lists different statistical measures of overall accuracy and accuracy for each class. Producing a random sample report 1. From the Accuracy Report dialog box, click the Sample Report Listing tab. 2. Click Generate Report. Producing an error report 1. From the Accuracy Report dialog box, click the Error (Confusion) Matrix tab. If you want to apply a 3 x 3 mode filter to each test pixel location in the classified image, enable the Apply Mode filter to classified values check box. The result of the mode filter operation are compared to the reference value in order to access its accuracy. 2. Click Generate Report. Producing an accuracy statistics report 1. From the Accuracy Report dialog box, click the Accuracy Statistics tab. If you want to apply a 3 x 3 mode filter to each test pixel location in the classified image, enable the Apply Mode filter to classified values check box. The result of the mode filter operation are compared to the reference value in order to access its accuracy. 2. Click Generate Report. Saving an accuracy report You can only save a report from the current tab. You can append the reports to the same text file. A text file can also be overwritten with the report from the current tab. To save an accuracy report 1. From the Accuracy Report dialog box, click Save Report. 2. In the Save Accuracy Report dialog box, click Browse. 3. In the File Selector dialog box, locate and select a file, and click Open. If you want to append the report to the selected file, click Append. If you want to overwrite the report in the selected 203

206 file, click OK. To clear all the samples in the Random Sample List 1. From the Accuracy Assessment dialog box, click Clear Sample List. To save a classification project 1. From the File menu, click Save Project. 2. In the File Selector dialog box, locate and select a folder where you want to save the project. 3. Enter a project name in the File name box. 4. Click Save. 204

207 Chapter 6 Information tools Information tools include histograms, image statistics, digital number (DN) profiles or sections of an image, and scatter plots. These tools do not change or process images, but do allow you to get a better understanding of the data you are using. Information tools, such as image band correlation statistics and histogram statistics, help you decide how you can further process image data. Opening the Information report You can display the individual attributes of selected features for rasters, vectors, and charts using the Information Report. For raster files, the Information Report provides the digital number (DN) values for the pixel identified by the cursor position. If an RGB file is used, the report includes the DN values for the red, green, and blue layers. The Information Report can also be used for grayscale or pseudo-color rasters. In these cases, only one DN value is reported. For vector files, the Information Report displays vector attributes. The report provides all attributes for a selected (under-the-pixel) vector. For charts, the Information Report displays attributes for the record corresponding to selected data in a chart. 1. From the Tools toolbar, click the Information button. The Information Report appears. You can use the Information Report with both raster and vector data. Viewing information for a selected vector 1. From the Information Report, enable the Selected shapes option in the Report on area. 2. On the Editing toolbar of the Focus window, click the Selection Tools arrow and choose Individual. 3. In the view pane, click a vector. The attribute information for the selected vector displays in the Information Report. You can also select several vectors at once. With several vectors selected, you can change the vector displayed in the Information Report. The cursor automatically moves to the current vector in the view pane. Viewing information for vectors under the cursor 205

208 1. From the Information Report, enable the Entries under cursor option in the Report on area. 2. In the view pane, click a vector. 3. On the Editing toolbar, click the Selection Tools arrow and choose Individual. 4. In the view pane, click a vector shape or segment. The Information Report shows the details of the selected vector. Showing information for raster data 1. Ensure that the raster data is opened in the view pane. 2. From the Information Report, enable the Entries under cursor option in the Report on area. 3. In the view pane, click a feature. The Information Report shows the DN values for the pixel of the selected feature for the top raster layer in the Maps tree. If multiple raster layers are open in the Maps tree, you can scroll between the DN values for the specified pixel in each of the layers by clicking the arrows in the Record area of the Information Report. All features, both visible and invisible, are reported by clicking a location in the view pane. You can show information for a new record in the current layer with the Record arrow buttons in the Information Report. Displaying the attributes from a chart 1. In the Chart viewer, click the Identification button. 2. Click a piece of data in the chart. The attributes for that record display under Values. Specifying the units of measurement The Measure tool reports length, area, and perimeter measurements of areas within imagery in the view pane. It allows you to draw areas and lines in several different ways, while reporting in the units of measure you choose. 1. With a file open, click the Measure arrow and choose one of the following menu options: Linear Units: displays units for a linear measurement Area Units: displays units for an area measurement Angle Units: displays units for an angle 2. Choose a unit of measurement from the corresponding menu option. A check mark next to a unit of measurement indicates it has been selected. Selecting a Measure tool 1. With a file open, click the Measure arrow and choose one of the following menu options: Line: lets you measure a linear object 206

209 Polygon: lets you measure a polygonal object Rectangle: lets you measure a rectangular object Ellipse: lets you measure an elliptical object Measuring a line 1. With a file open, click the Measure arrow and click Linear Units. 2. Choose a unit of measurement. 3. Click the Measure arrow and choose Line. 4. In the view pane, click where you want to begin measuring. 5. Move the cursor to the end of the measurement area. If you want to continue measuring in a different direction, click where you want to change direction and continue measuring. The total length, segment length, and azimuth appear at the bottom of the view pane. If you want to stop measuring, double-click the view pane. Measuring a polygon 1. With a file open, click the Measure arrow and click Area Units. 2. Choose a unit of measurement. 3. Click the Measure arrow and choose Polygon. 4. In the view pane, click where you want to begin measuring. 5. Click the next polygon vertex. Repeat this as necessary until you have at least three vertices in the polygon. The area and perimeter of the polygon appear at the bottom of the view pane. If you want to stop measuring, double-click the view pane. Measuring a rectangle or ellipse 1. With a file open, click the Measure arrow and click Area Units. 2. Choose a unit of measurement. 3. Click the Measure arrow and choose one of the following options: Rectangle Ellipse 4. In the view pane, click where you want to begin measuring. For a rectangle, the starting point is a corner of the measurement area. For an ellipse, start at the center of the measurement area. 5. Drag the rectangle or ellipse to cover the area you want to measure. The area and perimeter of the rectangle or ellipse appear at the bottom of the view pane. If you want to stop measuring, double-click the view pane. 207

210 Reading the Measure tool report Focus provides a report to help you keep track of your image measurements. You activate the Measurement Tool Report from the Options dialog box in the Tools menu. (See Measurement tools on page 112 ) When the Measurement Tool Report is active, the report window opens each time you take a measurement in the view pane. Information appearing in the Measurement Tool Report depends on the measurement tool you are using. Information is shown as either a linear or polygonal measurement. (See Specifying the units of measurement on page 206 ) Line Measure Reports: Reports a measurement for each segment of a line that includes the length, azimuth, and start and end coordinates. Polygon Measure Report: Reports the area, perimeter, and coordinates for each point in the polygon. For ellipse measurements, the report shows the perimeter and the area only. Viewing histograms and statistics Histograms graphically represent the count of each pixel value in an entire or a selected region of a raster. The statistical information that you obtain from the pixel values can help you in your analysis of a geographical area. You can access both histograms and statistics from the raster maps layer, and access the statistics from the file s raster. 1. In the Maps tree, select a raster map layer. 2. In the Focus view area, use the Zoom tools to select the area for which you want to view a histogram. 3. From the main menu, click Layer and then click Histograms. The Multi Histogram Display window appears if an RGB map layer is selected, otherwise, the Histogram Display window appears. 4. Proceed to Viewing a histogram on page 208. Viewing a histogram You can view a histogram of a grayscale, pseudo-color, or an RGB map layer. A histogram of the currently viewed area is first displayed. For an RGB map layer, a histogram is displayed for each RGB channel. At a glance, you can view the distribution of pixels and then select a histogram to view its statistics. For more information, refer to Viewing histogram statistics on page 209. You can also view a histogram of a region that is under a bitmap mask. For more information, refer to Viewing histograms under a bitmap mask on page In the Multi Histogram Display or Histogram 208

211 Display window, click a histogram to view the histogram statistics and other details. The Histogram with Statistics window appears displaying the histogram of the content currently viewed in the Focus viewer. 2. Proceed to Viewing histogram statistics on page 209. Viewing histogram statistics You can view statistics of a histogram that represent an entire raster, a region under a bitmap mask, or the current view displayed in the Focus viewer. You can also zoom into or out of the raster in the Focus viewer and watch the histogram in the Histograms with Statistics window change accordingly. To view histogram statistics of a region under a bitmap mask, refer to Viewing histograms under a bitmap mask on page 210. In addition to viewing statistics, you can zoom into portions of the displayed histogram, print, or export the histogram in its zoomed or original version. For more information, refer to Zooming into and out of a histogram on page 210,Printing a histogram on page 210, and Exporting a histogram on page Perform one of the following steps: In the Maps tree, perform steps in Viewing a histogram on page 208. In the Files tree, right-click a raster channel and select Histogram with Statistics. The Histgogram with Statistics window appears. 2. In the Histogram with Statistics window, move the mouse pointer over the histogram to view the current count of pixels for a given pixel value. The Statistics section provides you with further statistical information about the histogram. 3. If required, in the Pixel Value and Pixel Count fields, enter values of a particular area of the histogram. Press Enter. The histogram view displays the portion of the histogram that corresponds to the specified values. 4. If required, click Zoom to Overview to revert to the original histogram view. For information about Mask contents, refer to Viewing Mask contents on page 209. Viewing Mask contents You can view three types of histograms from the Mask list box in the Histogram with Statistics window: Entire raster view: displays a histogram of the entire raster. Current view area: displays a histogram of the area that is displayed in the Focus viewer. If you are zoomed in closer than 1:1, the actual data pixels are used. If you are zoomed out further than 1:1 the data pixels are approximated by using the rendered image. Bitmap layer: displays a histogram of a region under a bitmap mask. 1. Perform one of the following steps: In the Maps tree, perform steps in Viewing a histogram on page 208. In the Files tree, right-click a raster channel and select Histogram with Statistics. 209

212 2. In the Histogram with Statistics window, select an option from the Mask list box. When accessed from the Maps tree, the Mask list box displays the entire raster, current view, and any bitmap layers that are in the current area. The bitmap layers are listed whether they are saved or not. When accessed from the Files tree, the Mask list box displays the entire raster and the bitmap layers that are saved in the same, active source file. The saved bitmap layers are listed with their file and layer names displayed. For more information about viewing histograms for a bitmap layer, refer to Viewing histograms under a bitmap mask on page 210. Viewing histograms under a bitmap mask You can view histograms for regions that have been defined by bitmap masks. You must first create bitmap layers and then apply bitmap masks for the regions. For more information, refer to Creating a new bitmap layer on page 141 and Creating a mask on page In the Histogram with Statistics window, select the bitmap mask from the Mask list box. When viewing from the Maps tree, bitmap layers for which masks have not been applied are also listed in the Mask list box. If you select one of these layers and then apply a mask to a region in the Focus viewer, the Histogram with Statistics window refreshes with the relevant histogram. Zooming into and out of a histogram You can zoom into an area of a histogram that is displayed on the Histogram with Statistics window to view more detailed pixel values. 1. In the Histogram with Statistics window, position the cursor over the area of the histogram you want to zoom into. 2. Right-click and select Zoom In or drag a rectangle. You can click Zoom Out to revert to the previous view of the histogram and Zoom to Overview to revert to the original histogram. Printing a histogram You can print the displayed histogram or its zoomed version. 1. In the Histogram with Statistics window, select Fixed aspect ratio in the Options section, if required. 2. In the Background list box, select a background color for the histogram. The selected color appears behind the histogram. 3. Click Print and specify the printer settings. 4. Click Print. Exporting a histogram You can export the displayed histogram or its zoomed version to a file. 1. In the Histogram with Statistics window, click 210

213 Export. The File Selector window appears. 2. Specify the file name, format, and location. 3. Click Save. Working with numeric values The Numeric Values dialog box is an information tool that provides a numeric version of the digital number (DN) values in an image. The DN values for each band in an RGB image are displayed concurrently. The numeric information lets you explore relationships between DN values in different image bands at a specific pixel location. (See Opening the Numeric Values dialog box on page 211 ) Opening the Numeric Values dialog box The Numeric Values dialog box allows you to work directly with the pixel values in raster data. You can view and edit the individual pixel values for grayscale and RGB channels through individual tables. Each table provides a sample of values that correspond to the cursor coordinates in the view pane. You can change the sample of values by moving the cursor across the view pane. You can also switch the values to show either raw or enhanced data. Red, green, and blue pixel values are shown in separate tables. Raw Data: Switches numeric values to raw data values. Enhanced Data: Switches numeric values to enhanced data values. Line Numbers: The gray column on the right of a numeric values table shows the numbers for each line in an image. Pixel Numbers: The gray row at the top of a numeric values table shows the numeric value for a single pixel. Red Channel Value: The red pixel value for a selected pixel in the view pane. A red channel value is indicated by a red border in the numeric values table. Green Channel Value: The green pixel value for a selected pixel in the view pane. A green channel value is indicated by a green border in the numeric values table. Blue Channel Value: The blue value for a selected pixel in the view pane. A blue channel value is indicated by a blue border in the numeric values table. 1. In the Maps tree, select an RGB layer. 2. From the Layer menu, click Numeric Values. 211

214 You can export digital number (DN) values to a text file for further statistical analysis. You can also use the Numeric Values dialog box to change the DN values in an image. Exporting the numeric values to a text file 1. From the Numeric Values dialog box, click Export. 2. In the File Selector dialog box, locate and select a file. 3. Click Save. (See Interpreting the values on page 212 ). Change a color channel DN value The digital number (DN) values of an image channel can be altered directly. Only the image channels that are currently displayed can be altered. 1. In the Numeric Values dialog box, double-click the cell for the image layer and pixel location that you want to edit. 2. Type a value (between 0 and 255 for RGB) and press Enter. Note: You cannot alter enhanced values. (See Interpreting the values on page 212 ) Interpreting the values The Numeric Values dialog can be expanded to display more values. Each table displays one color-highlighted cell containing the RGB value of a selected pixel/line coordinate. The other cells contain the RGB values of the surrounding pixel/line coordinates. RGB values show the position of the cursor in the view pane. Raw and Enhanced Data The Numeric Values dialog box allows you to view the digital number (DN) values for both raw and enhanced DN values. The raw data values represent the DN values that are read directly from the image file. The enhanced data values represent the DN values as they are currently displayed in the view pane. For more information on enhanced data values. (See Changing a default enhancement on page 244 ) To display the RGB values for raw or enhanced data, enable the appropriate option. Making an image profile Image profiles show the spectral response of a selected feature along a user-specified cross-section. You can generate a spectral plot and a numeric values table from RGB or grayscale input channels along a user-defined vector. There are several instances where you can use an image profile. Your work will determine when and where you should use one. Following are examples where profiles have been used effectively. 212

215 Profiling can give you an idea of the spectral homogeneity for a feature. If profiles taken across a feature are all relatively flat, the feature is considered homogeneous for the particular wavelength in which the profile is taken. Relatively flat profiles indicate that a particular wavelength channel is a good input for a subsequent supervised classification where the extracted features are being investigated. As another example, you may want to establish a potential correlation between a characteristic of a feature in the scene and its spectral response. Such a correlation could be used in an image from the Coastal Zone Color Scanner (CZCS) satellite. The CZCS satellite measures important ocean properties from space. It was designed specifically to measure the temperature and color of the coastal zones of the oceans. The CZCS operates in six wavelength regions (bands), including bands in the visible, near-infrared, and thermal regions of the electromagnetic spectrum. The four visible bands are used to map phytoplankton concentrations and inorganic suspended matter, such as silt. The near-infrared channel can be used to map surface vegetation, while the thermal channel can be used to measure sea surface temperatures. You can use the Image Profile to examine changes in ocean properties as a function of distance from the coastline or along the perimeter of a coastline. You can demonstrate graphically how chlorophyll, temperature, suspended sediment, and gelbstoff (the yellow substance of interest to marine researchers) vary along the coastal waters in a CZCS image. Drawn across a DEM, a profile will give information on how the elevation changes from one point to another, giving a cross-sectional perspective of the terrain. 1. In the Maps tree, click an image layer. 2. From the Layer menu, click Profile. The vector profile is normally interpreted from left to right; however, if the end points of the vector occupy the same X position, the profile is interpreted from top to bottom. In the event of a closed shape, the profile is interpreted in a clockwise direction from the start/end node of the closed shape. The graph is a profile of the image layer and shows the input channels plotted with the gray values on the Y-axis, and the distance along the vector on the X-axis. The graph demonstrates how the gray values change with distance. Gray Values In the case of an 8-bit RGB image layer, the range of the Y-axis is 0 to 255 and represents the 256 possible gray-level values for each pixel of the red, green, and blue input channels. Distance The X-axis is measured in meters and represents the distance between the end points of the vector. The range of the X-axis depends on the length of the vector and the scale of the area or the ground distance covered by the image. 213

216 Using the mensuration bars You can change the viewable range for both the X and Y axes, export the plot to a graphic file, change the background color for the plot, and print the plot. 1. From the Profile Table, click Options. 2. In the Profile Options dialog box, click in the Current Channel column for a channel for which you want use the measuring tools. A red X indicates the channel is selected. 3. In the Profile Graph, drag the sliding bars to the region you want to measure. Selecting vector profiles If a vector is not selected, a simple line is automatically generated and used to calculate the profile. As an alternative, you can create a vector or select an existing vector for the profile. To modify the profile vector, use the Line Color editor or Vector Editing toolbar. 1. Draw or select an existing vector layer. 2. With either the Selection Tool cursor or the Vector Editing cursor, select the line in the view pane. The values change in the Profile Table and the line is updated in the Profile Graph. Using the spectra extraction tools You can extract spectra from image data using multispectral or hyperspectral data. You begin spectra extraction by configuring your data with the Spectra Extraction Configuration dialog box. Focus creates a hyperspectral metalayer to hold the extracted spectra. You must first specify the input file and channels you want to work with. You can select an existing channel or you can create a new one. (See About the Spectra Extraction Configuration dialog box on page 215 ) When you begin with no open data, the Spectra Extraction Configuration dialog box automatically creates a new Map and Area for your work. If a Map and an Area are already open in and the input file has the same georeferencing as the Area, a new metalayer is added to the Map and Area. When georeferencing is incompatible, a new Area is added to the existing Map. When you have configured a metalayer, you can access both the Scatter Plot and Spectra Plot dialog boxes from a menu in the Spectra Extraction dialog box. Scatter plots and spectra plots are automatically linked to the data you specify in the Spectra Extraction dialog box. (See Extracting spectra from a region of interest on page 215 ) The Spectra Extraction tools let you: Collect regions of interest from a hyperspectral image or a scatter plot. Review mean and ellipse information in a scatter plot for your spectra. Create and review spectra plots from a region of interest. Compare spectra signatures of regions with reference spectra from either a spectra library or another image. Save spectra to either an XLS or to an SPL library. 214

217 Extracting spectra from a region of interest You can define regions of interest manually in the view pane using the drawing tools and derive spectral signatures for them. You can manually create regions of interest using the New Shapes tool. The resulting spectral end members can be used as input into spectral processing algorithms for image classification and spectral unmixing. Hyperspectral spectra extraction provides linking between image regions of interest, scatter plots, spectra plots and spectral libraries. (See Configuring a hyperspectral metalayer on page 215 ) About the Spectra Extraction Configuration dialog box The Spectra Extraction Configuration dialog box lets you select input channel data and choose a bit depth for your output data. Input: Lets you enter a file name and location or browse for the data you want to use as input. Browse: Opens the File Selector dialog box, where you can locate and select input data. Region of Interest Channel: Lets you create a region of interest by either selecting a layer from the input data or creating a new layer. You can also set the bit-depth of a new layer. Layer: Lets you choose a layer from an input data file or create a new layer. Type: Lets you choose a bit-depth for a new layer. Accept: Opens the Spectra Extraction dialog box and transfers the settings you made in the Spectra Extraction Configuration dialog box. (See About the Spectra Extraction dialog box on page 216 ). Configuring a hyperspectral metalayer During spectra extraction configuration, a metalayer is created in the Files tree. When you right-click a new metalayer in the Maps tree, you open a sub menu with commands for the Spectra Extraction Configuration dialog box, the Spectra Extraction dialog box, the Spectra Plotting dialog box, and the Scatter Plot dialog box. You can link between the image and a region of interest defined by a mask layer and work with scatter plots and spectra plots. 215

218 Metalayer analysis is based on wavelength metadata. Files must be either.pix format or linked to a.pix file. The region of interest channel must be added to a.pix file when using compressed data. 1. From the Analysis menu, click Spectra Extraction. 2. In the Spectra Extraction Configuration dialog box, choose an input file from the Input list box. If no file is available, click Browse, locate and select a file in the File Selector dialog box, and click Open. 3. In the Region of Interest Channel area, choose a region of interest channel from the Layer list box. If you want to change the bit depth of the layer, choose one from the Type list box. You must select a channel type if you are creating a new layer. 4. Click OK. (See About the Spectra Extraction Configuration dialog box on page 215 ). About the Spectra Extraction dialog box The Spectra Extraction dialog box displays the channels in the regions of interest in a table and is linked to the Spectra Plotting dialog box. The spectra table lists the channels used to generate endmember or sample signatures from selected pixels within a region of interest. You can either choose a channel as a region of interest or create a new channel and draw a bitmap mask over the region in the view pane. The Spectra Extraction dialog box lets you specify details for a region of interest, edit the spectra list in the spectra table, change spectra attributes, and adjust layer opacity. (See Region menu on page 216 ) Region menu The Region menu has options for adding spectra channels, importing bitmap and vector layers, merging channels, and exporting channels to create new files. New: Adds a new channel to the spectra table. Import: Lets you import vector or bitmap data to the spectra table. Vectors: Allows you to import vector regions from an existing vector segment for regions of interest and opens the Import Vectors dialog box. (See About the Import Vectors dialog box on page 218 ) Bitmaps: Allows you to import bitmaps from an existing bitmap layer for regions of interest and it opens the Import Bitmaps dialog box. (See About the Import Bitmaps 216

219 dialog box on page 219 ) Merge: Allows you to merge multiple regions of interest that you select from a source region and opens the Merge Classes dialog box. (See Merging a spectra channel on page 220 ) Export Regions to Bitmaps: Lets you export a region to a bitmap. (See Edit menu on page 217 ) Edit menu The Edit menu has options that let you clear and delete the channels listed in the spectra table. Clear Selected: Clears a channel selected in the spectra table. Clear All: Clears all of the channels listed in the spectra table. Delete Selected: Deletes a channel selected in the spectra table. Delete All: Deletes all of the channels listed in the spectra table. (See Tools menu on page 217 ) Tools menu The Tools menu lets you access the Scatter Plot dialog box and the Spectra Plotting dialog box, and saves spectra to a Spectra Library. Scatter Plot: Opens the Scatter Plot dialog box. (See Viewing the scatter plot for a layer on page 232 ) Spectra Plot: Opens the Spectra plotting dialog box. (See Plotting spectra on page 221 ) Save Spectra Signatures: Opens the Save Spectra to Library dialog box. (See Saving a spectra plot on page 226 ) (See Spectra extraction table on page 217 ) Spectra extraction table The Spectra Extraction table lists spectra and lets you change several attributes in the table cells. Value: 217

220 Lets you change the channel value for a channel listed in the table. Name: Lets you enter a new name for a channel. Color: Shows the color of the bitmap layer for the channel showing in the view pane. Plot Mean: Lets you include the plot mean information with the spectra channel when you save the spectra extraction information. Plot Ellipse: Lets you include plot ellipse information with the spectra channel when you save the spectra extraction information. Description: Lets you enter and edit a brief description for the spectra channel. Opacity: Lets you set an opacity value for the spectra bitmap. An opacity value of 100% makes the spectra bitmap completely opaque. No underlying imagery is visible. An opacity value of zero makes the bitmap invisible. Underlying imagery is completely visible. Apply: Applies any changes you make with the Opacity slide control to the image in the view pane. Save and Close: Closes the Spectra Extraction dialog box and saves the changes you have made. Save: Saves the changes you have made but leaves the Spectra Extraction dialog box open. About the Import Vectors dialog box The Import Vectors dialog box lets you select vectors and choose the attributes you want to import to the Spectra Extraction dialog box. File: Opens the File Selector dialog box, where you can change the source files from which to import vector data. Destination Class: Reports the region you have selected in the Spectra 218

221 Extraction dialog box to which you are importing vectors. Segment: Lists the ID for a segment in the source data. Interior Points: Lets you include interior point data with the imported vectors. Polygon Boundary: Lets you include polygon boundary data with the imported vectors. Field: Lets you choose the attribute you want to include with the imported vectors. Description: Shows the descriptions for the vectors from the source files. Rasterize: Uses the data and information you have set in the Import Vector dialog box and imports it to the Spectra Extraction dialog box as rasterized data. About the Import Bitmaps dialog box The Import Bitmaps dialog box lets you choose bitmaps from your source data and import them to the Spectra Extraction dialog box. Import As: Lets you import a raster as a new channel in the Spectra Extraction dialog box or import it as the channel you have selected in the Spectra Extraction dialog box. New Class: Imports the raster and adds it to the Spectra Extraction table. Current: Imports a raster as the channel you have selected in the Spectra Extraction dialog box. Bitmap List Window: Lets you import the available bitmaps in the source data. Overwrite existing training areas: Lets you overwrite a selected channel in the Spectra Extraction dialog box. Import: Imports the selected rasters to the Spectra Extraction dialog box. 219

222 Merging a spectra channel The Merge Classes dialog box lets you merge the attributes of one channel listed in the Spectra Extraction dialog box into another channel in the list. Select Source Classes: Reports the value, name, color, and description of the available source channels. Value: Reports the channel value for a channel listed in the source table. Name: Reports the name of a source channel. Color: Shows the color of the source bitmap. Description: Reports the description for the source spectra channel. Select Destination Classes: Reports the value, name, color, and description of the available destination channels. Value: Reports the channel value for a channel listed in the destination table. Name: Reports the name of a destination channel. Color: Shows the color of the destination bitmap. Description: Reports the description for the destination spectra channel. 1. In the Spectra Extraction dialog box, click Region and then click Merge. 2. In the Merge Classes dialog box, choose a source channel from the Select Source Classes table. 3. In the Select Destination Classes table, choose a destination channel. 4. Click Merge. Saving a spectral extraction The Save Spectra Signatures dialog box lets you choose the files and spectra you want to save to the Spectra library. 1. Choose a file from the File list box. If no file is listed, click Browse, locate and select a 220

223 file in the File Selector dialog box, and click Open. 2. Choose a mask to exclude any bitmap segment from the Spectral Extraction file from the Mask list box. 3. Enable one of the following Spectra Ranges options: Channel # expresses spectra ranges in channels (bands) 1, 2#100 Wavelength # expresses the spectra ranges in wavelengths (800um#12,000um) 4. Type a range based on the selected spectra range type in the Range Value box. For example, if a spectra range is for a channel, an entered range of 5, -20, 30, -40 will yield spectrum taken from channels 5 to 20 and channels 30 to 40; if spectra range is for a wavelength, an entered range of 800, -1200, 1400, will yield spectrum taken from a wavelength of 800um to 1,200um and a wavelength of 1,400um to 2,000um. 5. Enable any of the following check boxes: Save selected Spectra only # saves only the spectra that you have selected Save ROIs to Bitmap layers # saves the spectra as a bitmap layer 6. Click Save. Plotting spectra You can plot spectra with an interactive graph tool that can be used independently or with the spectra extraction tools allowing you to compare the signatures from a spectra library with the spectra in your regions of interest. 1. From the Maps tree, select a layer. 2. From the Layer menu, click Spectra Plot. (See About the Spectra Plotting dialog box on page 221 ) About the Spectra Plotting dialog box The Spectra Plotting dialog box allows you to view and configure a detailed graph that plots radiometric quantity and wavelength.you can import spectra from several sources that include the cursor position in the view pane, a region of interest drawn in the view pane and listed in the Spectra Extraction dialog box, and spectra signatures from Spectra Library files. There are several tools that let you control the data display of the spectra you are plotting. You can show or hide the controls and then work with the graph values by zooming to any graph region along a plot line. The Spectra Plotting dialog box controls include: Active Radiometric Quantity and Wavelength graph Active Displayed Spectra table Data controls Hyperspectral Image adjustments Plotting Range settings Reports Graph Options and settings (See Radiometric quantity vs. wavelength graph on page 221 ) Radiometric quantity vs. wavelength graph 221

224 The Radiometric Quantity vs. Wavelength graph allows you to read radiometric and wavelength values for both regions of interest and spectra library signatures in the same graph. The X and Y scales can be adjusted using the Plotting Ranges and Graph Option controls. You can zoom to a region within the graph window by dragging your mouse over the region you want to enlarge. Library: Measures radiometric quantities for spectra library samples. Band Number or Wavelength [nm]: Measures the band number or wavelength of both the library samples and your source data. The the graph shows the unit of measure as Band Number or Wavelength in nm depending on the presence of radiometric transformation metadata in the sample data. When no transformation metadata is present, the values are shown as band numbers. Image: Measures radiometric quantities for the source data. (See Displayed spectra on page 222 ) Displayed spectra The Displayed Spectra table and controls lists the spectra signatures available for viewing in the Spectra plot graph. The table reports the spectra ID number, name, and color. The Displayed Spectra controls allow you to show, hide, and change the color of the spectra plot lines and to choose new samples from a Spectra Library and new areas of interest. ID: Assigns a number to spectra signatures in ascending chronological order. Name: Lists the names of each spectra signature. Color: Lists the plot line colors for each spectra signature in the table. You can change the color of a signature plot line in the graph. Show: Lets you show or hide a signature plot line. From Spectra File: Opens the Select Spectra From Library dialog box. You can change spectra libraries and choose more spectra signatures. (See Selecting a spectra library on page 225 ) From Regions: 222

225 Imports spectra listed in the Spectra Extraction dialog box table and makes them available for viewing in the Spectra Plotting dialog box. From Image: Imports spectra from the cursor position within the view pane and adds the spectra values to the table, making them available for viewing in the Spectra Plotting dialog box. Clear Spectrum: Clears a selected spectrum from the Display Spectra table. Clear All: Clears all of the spectra signatures listed in the Display Spectra table. Save Spectra: Opens the Save Spectra to Library dialog box, where you can add a spectra to a Spectra library. (See Saving a spectra plot on page 226 ) Window Size Around Cursor: Lets you choose a kernel size for the sample taken in the view pane at your cursor location. Spectra Quantity to Sample: When your data contains radiometric transformation metadata, the transformed spectra are listed in the Spectra Quantity to Sample box. You can choose which of the transformation quantities you want to sample from the list. The possible radiometric transformations are: Uncalibrated digital number (DN) values Non-physical adjustment At-sensor (apparent) radiance Scene radiance Scene irradiance Reflectance Hyperspectral Image: Let you work with hyperspectral image data. Wavelength First: Lets you adjust the starting wavelength value upward from the default hyperspectral wavelength, read from the file data. Last: Lets you adjust the last wavelength value downward from the default hyperspectral wavelength, read from the file data. Mask: Allows you to choose bitmap masks in your source files. 223

226 (See Graph options on page 224 ) Graph options The Graph options allow you to change the way the graph lines for the Spectra plot are shown. Overlay: Lets you show numbered scales on the graph for library, image, and wavelength values. Plot lines are superimposed so that the values can be compared directly. Stack: Shows a numbered scale for wavelength values only. Plot lines are separated so that the plot shapes can be compared. Offset: Lets you enter an offset for the graph plot lines. (See Plotting ranges on page 224 ) Plotting ranges The Plotting Ranges area lets you set several parameters for a spectra plot. Adjust Plot Range To Data: Automatically adjusts the spectra plot to show all the values in the data. X-axis Min: Lets you enter a minimum range for the graph X-axis. Max: Lets you enter a maximum range for the graph X-axis. Image Min: Lets you enter a minimum range value for data plotted from the cursor position in the view pane. Max: Lets you enter a maximum range value for data plotted from the cursor position in the view pane. Library Min: Lets you enter a minimum range value for data plotted from a spectra library signature file. Max: Lets you enter a maximum range value for data plotted from a spectra library signature file. Same As Image: 224

227 Matches the graph values to the cursor values from the image in the view pane. (See Report on page 225 ) Report The report area reports information for spectra signatures selected in the Displayed Spectra table based on both the entire spectra and on specific pixel/line coordinates. Current Spectrum: Reports the ID for a spectra selected in the Displayed Spectra table. Wavelength: Reports the wavelength of a spectra selected in the Displayed Spectra table. Intensity: Reports the intensity of a spectra selected in the Displayed Spectra table. Current Pixel: Reports the pixel location. Current Line: Reports the line location. Wavelength: Reports the pixel wavelength value for the pixel/line location. Intensity: Reports the pixel intensity value for the pixel/line location. Hide Controls and Show Controls: Hides or shows all controls for the Spectra Plot panel. Zoom In: Zooms into the plot lines in the spectra plot graph. Zoom Out: Zooms out of the plot lines in the spectra plot graph. Zoom Overview: Zooms the plot lines in the spectra plot graph to an overview showing the extents of the plotted values. Selecting a spectra library The Select Spectra From File dialog box lets you open spectra library files, choose spectra, and add them to the table in the Spectra Plotting dialog box. Spectra File: 225

228 Lets you enter a spectra file from which to choose spectra signatures. Browse: Lets you find a spectra file from which you can select files for export to the Spectra Plotting dialog box. Library window: Lists the spectra contained in an open spectra file. Add to Plot: Exports the selected spectra in the list in the Library window to the Spectra Plotting dialog box. 1. From the Spectra Plotting dialog box, click From Spectra File. 2. In the Select Spectra From Library, choose a library file from the Spectral Library list box. If no library file is listed, click Browse and locate and open a different spectra library file or folder. Spectra libraries use a.spl file name extension. 3. In the Spectra Library, select the spectra you want to add to the Spectra Plotting table. 4. Click Add to Plot. Changing the graph options The Select Spectra From File dialog box lets you open spectra library files, choose spectra, and add them to the table in the Spectra Plotting dialog box. Spectra File: Lets you enter a spectra file from which to choose spectra signatures. Browse: Lets you find a spectra file from which you can select files for export to the Spectra Plotting dialog box. Library window: Lists the spectra contained in an open spectra file. Add to Plot: Exports the selected spectra in the list in the Library window to the Spectra Plotting dialog box. 1. Choose either Channel Number or Wavelength from the X axis labelling list box. 2. Choose a wave record from the Wave record list box. 3. Choose a number to represent the window size from the Window size around cursor list box. Saving a spectra plot You can choose the files and spectra you want to save to the spectra library. 1. Choose a file from the File list box. If no file is listed, click Browse, locate and select a file in the File Selector dialog box, and click Open. 226

229 2. Enable any of the following check boxes: Save selected Spectra only: saves only the spectra that you have selected Save ROIs to Bitmap layers: saves the spectra as a bitmap layer 3. Click Save. Opening the DEM Editing dialog box Digital elevation models (DEMs) may contain pixels with failed or incorrect values. You can edit a DEM to smooth out irregularities and create a more accurate model. For example, areas such as lakes often contain misleading elevation values; setting those areas to a constant value improves the model. For suggestions about how to correct common irregularities, see Applying tool strategies for common situations in digital elevation models on page From the Analysis menu, click DEM Editing. Editing a DEM 1. From the DEM Editing dialog box, choose a DEM from the File list box. If no DEM is available, click Browse and open a file from the File Selector dialog box. 2. Choose a layer that contains the DEM from the Layer list box. 3. Type the value assigned to pixels that have no elevation values because the image correlation failed in the Failed box. Some features are not accessible unless you enter a failed value. 4. Type the value assigned to the area that lies outside the DEM in the Background box. The background value can be a maximum or minimum value such as -150 or Some features are not accessible unless you enter a background value. If you want to see the results without saving the new layer, enable the Display option. If you want to save the new layer in the project, enable Save option and choose a file from the File list box. Type a name for the new layer or select an existing layer from the Layer list box. If you want to display the results in the view pane, enable the Display saved results check box. 5. If you want to apply the edits repeatedly and achieve a cumulative effect on the data, enable the Load results to input check box. You can use a mask to identify specific areas that you want to edit. The mask itself does not change the values in the area that it covers, but you can use the tools in the Area Fills Under Mask and Filtering and Interpolation areas to edit the data under the mask. Opening an existing mask 227

230 1. In the DEM Editing dialog box, click Open a Mask Layer. To create a mask, see Creating a mask on page 228. To modify the values under the mask, see Replacing the elevation values under a mask on page 228. To edit the DEM, see Filtering and interpolating DEM values on page In the Select Layer dialog box, click Browse. 3. In the File Selector dialog box, navigate to and select the file. 4. Click Open. The file and its available layers are displayed in the Select Layer dialog box. 5. Select a layer and click OK. Creating a mask A mask is a vector shape that identifies specific areas that you want to edit. The mask does not change the values in the area that it covers. 1. From the DEM Editing dialog box, click the New Mask Layer button. 2. In the Maps tree, select the new bitmap layer. 3. Use the New Shapes tools to draw a shape over the area that you want to edit. For more information about the New Shapes tools, see Adding points to an active layer on page 303. Replacing the elevation values under a mask Once you have created a mask, you can replace the unsatisfactory value. To replace values with a failed value 1. Create a mask. 2. In the DEM Editing dialog box, click Fill. To replace values with respective averages 1. Create a mask. 2. In the Area Fills Under Mask area, choose Average of Each Shape from the Fill using list box. 3. Click Fill. To replace a value with global average 1. Create a mask. 2. In the Area Fills Under Mask area, choose Average of All Shapes from the Fill using list box. 3. Click Fill. To replace a value with a specific value 1. Create a mask. 2. In the Area Fills Under Mask area, choose 228

231 Specified Value from the Fill using list box. 3. Type a value in the Value box. 4. Click Fill. To remove a mask 1. In the DEM Editing dialog box, click the Clear Mask button. To hide a mask 1. In the Maps tree, disable the new bitmap layer check box. To save a mask 1. In the DEM Editing dialog box, click Save the Mask. Filtering and interpolating DEM values You can use the filters available under Filtering and Interpolation to eliminate failed or incorrect values in a DEM. You can apply each filter repeatedly and in different combinations to achieve a cumulative effect. You can also limit the effect of the selected filter to a specific area by creating a mask. Remove Noise Filter Noise refers to pixels containing distorted or failed values. Because pixels adjacent to failed pixels also tend to contain incorrect values, the Remove Noise Filter uses two filters to identify failed pixel values and their surrounding pixels: The first filter calculates the average and variance of the eight elevation values immediately surrounding each pixel, excluding failed and background pixels. If the center pixel is more than two standard deviations away from the average, it is replaced with the failed value. The second filter counts the number of failed values immediately surrounding each pixel. If five or more failed pixels border the center pixel, the center pixel is also set to a failed value. Erode holes Because pixels adjacent to failed pixels also tend to contain incorrect values, the Erode holes filter replaces the eight pixels around each failed pixel with the failed value. When you apply the filter under a mask, the mask enlarges to cover any additional pixels replaced by the failed value. Median Filter Ranks the pixel values within a 5x5 pixel frame according to brightness. The median is the middle value of those image pixel values, which is then assigned to the pixel in the center of the frame. Smooth DEM Is a Gaussian filter that calculates the weighted average of all the pixels in a 3x3 pixel frame and assigns the value to the center pixel in the frame. Failed and background 229

232 pixel values are not replaced by the filter and are not used in the Gaussian calculation. Interpolate Replaces failed values with an estimate weighted by distance calculated from the valid pixels surrounding the failed pixel(s). The algorithm used to calculate the estimate is adequate for small areas of less than 200 pixels, but is not recommended for larger areas. To limit the filter to a specific area, you must create a mask. 1. From the DEM Editing dialog box, choose a filter from the list box in the Filtering and Interpolation area. 2. Enable one of the following options: 3. Click Apply. For more information, see Applying tool strategies for common situations in digital elevation models on page 230. Applying tool strategies for common situations in digital elevation models Editing DEMs requires an understanding of the desired results. Each DEM presents a variety of problematic situations. The following examples present the most common problems and provide some methods to handle them. Adjusting pixel values for a lake Because lakes have no features that can be used for matching during DEM extraction, lakes in a DEM often contain failed pixel values or incorrect elevation values. 1. Create a mask over the lake. 2. Identify the elevation of the lake. 3. In the DEM Editing dialog box, choose Specified Value from the Fill using list box in the Area Fills Under Mask area. 4. Type a value for the lake elevation in the Value box. 5. Click Fill. 6. Click the Clear Mask button. Adjusting the pixel values for multiple lakes 1. Create a mask over each lake. 2. In the DEM Editing dialog box, choose Interpolate from the list box in the Filtering and Interpolation area. 3. Enable the Use Mask option. 4. Click Apply. 5. In the Area Fills Under Mask area, choose Average of Each Shape from the Fill using list box. 6. Click Fill. 7. Click the Clear Mask button. Compensating for forests and urban areas The repetitive textures of forests and urban areas often cause those areas to contain a lot of failed values, noise, and poorly correlated elevation values. 230

233 1. Create a mask over the area. 2. In the DEM Editing dialog box, click Fill Mask from Failed. 3. Choose Interpolate from the list box in the Filtering and Interpolation area. 4. Enable the Use Mask option. 5. Click Apply. 6. Click the Clear Mask button. Neutralizing cloud-covered areas When clouds obscure a large area over rugged or mountainous terrain, the area may be too complex to interpolate. To avoid confounding the data, you can set the entire area to the background value. 1. Create a mask over the area. 2. In the DEM Editing dialog box, choose Specified Value from the Fill using list box in the Area Fills Under Mask area. 3. Type the background value in the Value box. 4. Click Fill. 5. Click the Clear Mask button. Removing noise from a DEM Noise is a random occurrence of irrelevant or miscorrelated values distributed throughout a DEM that reduces its accuracy. The following procedure usually produces a satisfactory DEM, except for areas containing large bodies of water, such as lakes. 1. Ensure all large bodies of water, such as lakes, have been fixed. See Adjusting pixel values for a lake on page In the DEM Editing dialog box, enable the Load results to input check box. 3. Choose Remove Noise Filter from the list box in the Filtering and Interpolation area. 4. Enable the Entire DEM option. 5. Click Apply. 6. Click Apply again. 7. Choose Interpolate from the list box in the Filtering and Interpolation area. 8. Enable the Entire DEM option. 9. Click Apply. 10. Choose Smooth DEM from the list box in the Filtering and Interpolation area. 11. Enable the Entire DEM option 12. Click Apply. 13. Click Apply again. Selecting the DEM layer The Layer Selection dialog box lets you specify the DEM channel you want to edit. Browse: Opens the File Selector dialog box. Files: Lists the files selected from the File Selector dialog box. Channels/Segments available: Lets you select channels and segments for editing. 231

234 1. From the Layer Selection dialog box, click Browse. 2. In the File Selector dialog box, locate and select a file, and click Open. 3. In the Files pane, select a file. 4. In the Channels/Segments available pane, choose a DEM layer and click OK. (See Editing a DEM on page 227 ) Viewing the scatter plot for a layer Scatter plots are primarily used as data visualization tools. Each plot shows the correlation between the histograms for two channels. Pixel distributions for the two specified image channels display in the scatter plot using one channel as the X-axis and the other as the Y-axis. They allow you to see where the majority of data values (or pixels) are concentrated. Frequency values at each point are color coded. Scatter plots also calculate relevant statistics and display at the bottom of the scatter plot. Natural groupings of the spectral data are best illustrated with a two-channel data set. For image data with more than two channels, it is difficult to plot the values and visually identify natural spectral groupings. Statistical techniques can be used to automatically group an n-dimensional set of observations into natural spectral classes. This procedure is called cluster analysis. A scatter plot can reduce the number of channels used for a classification. If two channels have a very high correlation, you can omit one or the other as input for the classification. You can also determine which portion of the spectra a given bitmap or training area occupies, and you can use a scatter plot to determine the homogeneity of a bitmap or training area. If the scatter plot for the bitmap is tightly clustered with few outlying pixels, the spectral response for that area is homogenous in the selected image layers. You can open the Scatter Plot dialog box from the Layer menu or from the training area collection window for a supervised classification. Plot Scale For 8 bit imagery, the scatter plot axis are 256 pixels by 256 pixels. The top-left pixel represents the number of pixels with a value of 255 for the input channel on the Y-axis and zero for the input channel on the X-axis. The bottom-right pixel represents the number of pixels with a value of 255 for the input channel on the X-axis and zero for the input channel on the Y-axis. When images are outside the range, the imagery is scaled to fit within that range. When images are outside the range, the maximum digital number (DN) value is used for the plot scale. Pixel Brightness Is determined by the frequency of pixels in the image with a given gray-level value. Bright areas indicate common combinations and black areas indicate combinations that rarely occur. 232

235 1. From the Maps tree, select an image layer. 2. From the Layer menu, click Scatter Plot. Scatter plots typically show a bright smear in one area of the plot. By default, the plot appears with input channel 1 on the X-axis and input channel 2 on the Y-axis. In the controls area of the Scatter Plot dialog box, you can specify the channels you want to show as the X and Y axes. A color scheme for the plot and a look-up table (LUT) can be applied to either channel. Changing the input channel for the X and Y axes: 1. From the Scatter Plot dialog box, choose a channel from the X axis and Y axis list boxes. The frequency is displayed using a simple grayscale or a pseudo-color table. Mask: The Mask option allows you to create a scatter plot of a region under a bitmap mask. You can also create a scatter plot of the entire raster. When creating a scatter plot of the entire raster, you set the Mask option to None. The Mask list box displays all of the bitmap layers that are in the current area. The bitmap layers are listed whether they are saved or not and for each saved bitmap, both the file and layer names are displayed. Statistics: The Statistics section displays the linear equation derived from a linear regression calculation and the correlation coefficient associated with the scatter plot. A value of 'N/A' (Not Applicable) is given if these statistics cannot be calculated (usually if one of the selected channels is empty). The correlation coefficient measures the similarities of the two image channels. A value of one indicates a complete correlation between two images, whereas a value of zero indicates there is no correlation between images. The A -1 value indicates a negative correlation. Using the Scatter Plot dialog box (For the Hyperspectral Scatter Plot only) To specify which values are compared 1. From the Hyperspectral Scatter Plot dialog box, enable one of the following options: Entire file: plots all the values in the two channels Selected classes: plots only the values in the selected regions of the two channels (the Mask list is disabled) To change the color scheme of the display 1. From the Scatter Plot dialog box, enable one of the following options: Gray: displays the plot with grayscale representation 233

236 Pseudo: displays the plot with pseudo-color representation Because the human eye can only detect approximately 16 shades of grey, the scatter plot is more easily interpreted when displayed in pseudo-color with a white background. You can apply an LUT to either input channel. To apply an LUT to the X or Y-axis input channel 1. From the Scatter Plot dialog box, enable the Apply LUT check boxes for the X- and Y-axis channels. To hide the controls 1. From the Scatter Plot dialog box, click Hide Controls. Zooming into and out of a scatter plot You can zoom into an area of a scatter plot that is displayed in the Scatter Plot dialog box. 1. In the Scatter Plot dialog box, position the cursor over the area of the scatter plot you want to zoom into. 2. Right-click and select Zoom In or drag a rectangle. You can click Zoom Out to revert to the previous view of the scatter plot and Zoom to Overview to revert to the original scatter plot. Using the graph controls Click Graph Controls at the bottom of the Profile Graph dialog box. You can also right-click in the profile and select Graph Controls from the shortcut menu. Use the Graphic Controls dialog box to Change the viewing range Export the plot to a graphic file Show and hide the plot legend. Fix the plot aspect ratio Change the plot background color Print a plot You can ensure the image information is not distorted by fixing the aspect ratio. To open the Graph Controls dialog box 1. From the Scatter Plot dialog box, click Graph Controls. To fix the aspect ratio of a plot 1. From the Graph Controls dialog box, enable the Fix aspect ratio check box. To print a scatter plot 1. From the Graph Controls dialog box, click Print. Changing the x and y view ranges 234

237 You can control the range and hold the X and Y axes to the original relationship. 1. In the X View Range and Y View Range areas, enter a value in the Min and Max spin boxes. The default range of values for 8-bit imagery is 0 to 255. The range varies depending on the ground distance covered by an image and the length of a vector. Exporting a profile You can change the file format before selecting an output file. 1. In the Graph Controls dialog box, choose a file format from the Format list box. 2. Click File. 3. In the File Selector dialog box, enter a file name in the File name list box. 4. Click Save. 5. In the Graph Controls dialog box, click Export. Working with legend and color controls To show a legend for the color scale From the Graph Controls dialog box, enable the Show legend check box. To change the background color for a scatter plot From the Graph Controls dialog box, choose a color from the Background palette. Interpreting a profile table In the case of an RGB layer, a Profile Table is a numerical representation of the RGB input channels of an active image. Sample Points and Distances The table lists numeric information for each sample point along the current profile. A sample point is a pixel. The spacing is determined by the pixel size. The range depends on the length of the vector and the image scale. A field is displayed for each of the channels that is marked Visible in the Profile Options area. 1. From the Profile Table dialog box, click Options. Profile Options: Gives you control over various aspects of the profile graph and table. You can control the following properties: Color: Displays the color used to represent each channel on the profile graph. You can change any color by clicking on the color chip you want to change. This opens the Line 235

238 Color editor based on the RGB color space. The color representation of the channel's profile on the graph is changed. Visible: A check mark in this field indicates that a particular channel is visible in the profile graph and profile table. Current Channel: Indicates which plotted channel is associated with the mensuration bars. There can be only one current channel, which is indicated by an X. To select the current channel, click the appropriate field under the Current Channel column. Profile View: Sets the coordinates for the horizontal axis of the Profile Graph. The sample point coordinates are based on the image pixel size, in meters. Choose between Georeferenced and Sample Point coordinates. If Georeferenced is selected, the values in the X axis are displayed in metres. If Sample Points are selected, the values in the X axis represent pixel units. For example, if a vector line is 8000 m long, the maximum value for the X axis if georeferenced is selected in the Profile options is If the imagery has a resolution of 30 m, the maximum value for the same line displayed using Sample points is approximately 267 (8000/30). Changing the color of a channel Color spaces have been developed as a means of describing color. Two of the most common color spaces are RGB (Red-Green-Blue) and CMY (Cyan-Magenta-Yellow). The former is used by monitors and the latter is usually used by printers. RGB and CMY can be difficult to understand. Another color space, IHS (Intensity-Hue-Saturation) give a more accurate representation of how the eye interprets color. IHS transformations are useful in digital image processing, as they allow for greater control over the components that make up color. You can change the color of any channel by clicking on its color chip. This opens the Line Color editor. The color representation of a channel#s profile on the graph is changed. 1. Click the color chip for the corresponding channel. 2. In the Line Color editor, move the Red, Green, or Blue slide controls to the left or right to adjust your colors. 3. Click Close. To customize the color of the profile vector, use the Set Line Color tool on the Display toolbar. Changing the profile vector color 1. Click a line. 2. On the Display toolbar, click the Set Line Color 236

239 arrow and choose a color from the color palette. (See About the Change Color dialog box on page 237 ) About the Change Color dialog box The Change Color dialog box allows you to create a custom color using one or a combination of the following palettes: Basic Colors: Is a palette of basic colors that are preset and cannot be modified. Color Continuum: Is a palette composed of all possible hue/saturation combined values. Intensity/Lightness Scale: Controls the brightness of the color. It is the only palette available if the chosen color model is Gray. The color you create using the palettes is visually displayed alongside the color that is being replaced. These are referred to as the New and Old colors, respectively. The numeric representation of the new color opens in a series of data entry fields. You can edit the entries in these fields and the new color changes accordingly. The number of fields present corresponds to the chosen color model. RGB: Is one of the additive color models and is based on the light being emitted from computer monitors. The three primary colors are red, green, and blue. Combining the red, green, and blue colors in various proportions produces all the colors on your screen. CMYK: Is one of the subtractive color models and is based on the amount of light being absorbed and reflected by an ink film. This model is often used in printing. The primary colors are cyan, magenta, yellow, and black. HLS/HIS: Is a more intuitive model based upon the way we perceive color. The primary components are hue (shade of color), lightness/intensity (brightness of color), and saturation (strength or purity of color). Gray: Is a continuum of gray values ranging from pure black to pure white. Printing without the mensuration bars showing 237

240 You can print the profile graph by clicking Print at the bottom of the Graph Controls dialog box. 1. Open the Profile Table dialog box. 2. Click Options. 3. In the Profile Options dialog box, click Close. 4. In the Graph Controls dialog box, click Print. Using the profile statistics You can open the Profile Statistics dialog box by clicking the Statistics button in the Profile Table dialog box. Statistics are shown for each RGB channel in the selected layer. The dialog box calculates the minimum, maximum, average, weighted average, and weighted average summary statistics for the sample gray values along the profile. Weighted average is the most accurate measure of central tendency among sample points. The weight of a sample gray value is the ratio of the length of a sample interval over the total distance of all the sample intervals. Controlling the cursor You can use the Cursor Control dialog box to specify or determine the location of the cursor in the view pane. To open the Cursor Control dialog box, click the Cursor Control button on the Tools toolbar. The cursor control information shows both the location on the map page and to the georeferenced ground location represented in the image. The Cursor Control dialog box has four areas that display the cursor position in different coordinate systems. You can move the cursor in any of the supported coordinate schemes by changing the any of the coordinates. The Paper area measures the paper size set for the Map. It can be larger than the area view where imagery is displayed. The paper size can be changed in the Maps tree by right-clicking the Map layer and choosing Properties. From the Map Properties dialog box, choose Properties and then click the Page Setup tab. The cursor control panel shows the location in millimetres with the origin at the bottom right of the map. If more than one file is opened in the view pane, the coordinates are based on the selected database. You can change the database file. The result is the pixel and line that the cursor points to in the currently selected database. The file origin, (0,0) is the top left of the image or file. If the projection has not been set for a file, the database coordinates are not displayed. The Geocoded area displays the cursor coordinates in geocoded coordinates (for example, Eastings and Northings) according to the geocoding shown in the Cursor Control dialog box. If opened data has no associated geocoded locations, the geocoded location is shown in pixels and lines. The units displayed indicate the geocoding type. The User Defined Projection area shows Lat/Long coordinates as the default if sufficient geocoding information is available for the viewed data. Typically, UTM data with a valid zone number must be provided for 238

241 this transformation to occur. If a projection has not been set, the User Defined Projection coordinates are not displayed. Opening the GPS tool The GPS Tool provides two functions: you can use it to update the position of the cursor within an Area layer and as a data input device for a new vector layer. In either case, you must have an Area layer that contains the appropriate georeferencing information open. Before the GPS Tool can be opened, the GPS Receiver/Focus connection must be set. The GPS receiver connection is made through the Focus Options dialog box. (See Setting up a GPS receiver on page 111 ) 1. Ensure a GPS receiver is connected to the system according to manufacturer specifications and that it is set up correctly. 2. From the Tools menu, click GPS Tool. Using the GPS tool 1. Ensure a GPS connection has been established. 2. Open an Area layer containing appropriate georeferencing information. The georeferencing bounds should correspond to the area where the GPS receiver is located. If the GPS receiver is outside of these bounds, you cannot update the cursor or collect vectors. 3. From the Tools menu, click GPS Tool. When the GPS Tool is active, you can use it to update the cursor position or to add vector data to an Area in the project. Updating the cursor position using the GPS receiver 1. Ensure the GPS Tool is open. 2. From the GPS Tool dialog box, click one of the following buttons: Capture Stream: automatically updates the cursor position at the specified stream interval. For more on stream interval. (See Setting up a GPS receiver on page 111 ) If you want to stop the stream capture, click Finish. Capture Point: moves the cursor only once. To reset the cursor position using the GPS Receiver, click the button again. Inputting vector point data using the GPS receiver 1. Ensure the GPS connection has been established. 2. In the Maps tree, right-click an Area layer and click New Vector Layer. 3. In the New Vector Layer dialog box, enable the Point option. 4. Click OK. 5. In the Maps tree, select New Point Layer. 6. On the Editing toolbar, click the New Shapes arrow 239

242 list and click Points. 7. In the GPS Tool dialog box, click one of the following buttons: Capture Stream: adds new points to your vector layer at the specified stream interval. If you want to stop the point capture, click Finish. Capture Point: adds a new point to your vector layer. You can continue to collect points by repeatedly clicking the button. Inputting vector line or polygon data using the GPS receiver 1. Ensure the GPS Tool is open. 2. In the Maps tree, right-click an Area layer and click New Vector Layer. 3. In the New Vector Layer dialog box, enable one of the following options in the Layer Type area: Line Topological Line Polygon Topological Polygon 4. Click OK. 5. In the Maps tree, select the new layer. 6. In the GPS Tool dialog box, click one of the following buttons: Capture Stream: adds a new vertex to the vector layer at the specified stream interval. New vertices are added to the line or polygon until you click Finish. Capture Point: adds only the initial vertex to the line or polygon layer. You can continue to collect vertices for the line or polygon by repeatedly clicking the button. Using the ADAPT algorithm You can use a single channel with a pseudo-color table (PCT) to represent data instead of a full three-channel RGB image. This helps if you need to import data to software that accepts only single-channel.tif files with PCTs. It can also be used to reduce an RGB file to a third of its original size. You can also change data from a single-image channel with a PCT to full RGB representation. When preparing color images for export to third-party software (for example, a GIS system with limited color capability), the RGB2PCT compresses a 24-bit color (RGB) image into a single 8-bit layer based on a PCT. A PCT colors the compressed image to look similar to the original 24-bit color image. The input file (FILE) contains the input RGB layers (DBIC) and the target layer where the compressed result (DBOC) is saved. When enhancing image data with an LUT, it should first be applied to the RGB layers using the LUT PACE program. The input RGB layers and the output-compressed layer should be 8-bit. This restriction is due to the 8-bit nature of a PCT. While any type of image layer can be used, values are internally converted to 8-bit data. Using non 8-bit data may result in unexpected results. 1. Open and run the ADAPT program from the Algorithm Library to generate a well-distributed PCT to represent a particular image. 240

243 2. Choose RGB2PCT from the Algorithm Library. 3. Select three raster layers you want to use as your RGB channels. 4. Select the PCT that was created using ADAPT. 5. Run RGB2PCT and save the results in the Maps tree. Also see PCTMAKE, CMPRSS8, and ERRDIFF in the Algorithm Library. Converting RGB to pseudo-color 1. From the Algorithm Library, run the algorithm ADAPT. ADAPT takes a 24-bit RGB image and compresses it to a single 8-bit image, based on a user-supplied PCT. For each pixel, the nearest color in the supplied PCT is established and a corresponding color index is placed in the output channel. The results from ADAPT are used as input into the RGB2PCT program. RGB2PCT takes a 24-bit RGB image and compresses it to a single 8-bit image, based on a user-supplied PCT. For each pixel, the nearest color in the supplied PCT is established, and a corresponding color index is placed in the output channel. Converting RGB to pseudo-color PCE encodes an input channel into three output channels (such as red, green, and blue components) using a PCT held in a database segment. Opening the PCT Editing dialog box You can create and modify PCTs in the PCT Editing dialog box. A pseudo-color layer appears in the Maps tree as an icon with vertical color bars followed by layer file information. A PCT is generated only for an image layer that is designated as a PCT layer. From the Maps tree, right-click a pseudo-color layer and click Edit PCT. Adjusting the pseudo-color for single values 1. From the PCT Editing dialog box, click the Single Value tab. 2. Click one of the following buttons: Smooth: creates a smooth color ramp from dark blue to magenta Stepped: creates a series of short color ramps Random: creates a set of random colors Gray Ramp: creates a gray ramp with a black value of 0 and a white value of 255 From the Algorithm Library, run the PCE algorithm. Editing a value 241

244 The Current Pseudo-Color Table displays color values for the current PCT. You can edit the breakpoint and RGB values in the table cells. 1. In the PCT Editing dialog box, double-click the cell you want to change and type a new value. If you want to select multiple PCT entries, drag over a series of list entries. Selecting a basic color value Color Selection lets you modify the output color of the current PCT using the controls in the Color Selection area. The following is a list of the controls in the color selection area: Basic color sample table Basic color sample bar Color selection control Color Model list Old and New sample boxes Red, Green, and Blue boxes Gray Value box Apply command 1. Select a color model from the Model box. 2. Click a tile in the Basic Colors table. The color range changes in the Color Continuum and Intensity controls. 3. If required, use the Color Continuum, Instensity, or color value boxes to adjust the selected color. 4. Click Apply. Customizing range-based pseudo-color tables You can edit PCT channels for range-based pseudo-color. Standard and custom color selections are available under the Range-based tab. You can maintain existing PCT colors or replace them with predefined standard PCT color values. 1. From the PCT Editing dialog box, click the Range-based tab. Using standard mode 1. From the PCT Editing dialog box, click the Range-based tab. 2. Enable the Standard option in the Color Selection area. Keeping the original color values You can maintain or revert to the original pseudo color values. 1. Click Use Original PCT. Selecting colors within the range 242

245 1. From the Range-based page, enable the Custom option in the Color Selection area. 2. Drag the left and right markers to the positions you want on the color bar in the Color Selection area. Applying pseudo colors to pixel values in a raster You can render pseudo RGB color values to the pixel values of the active raster. This allows you to distinctly view specific areas of the raster. 1. In the Maps tree, right-click the pseudo-color layer and select Edit PCT. The PCT Editing window appears. 2. Click the Range-based tab. 3. In the Color Selection area, click Custom. 4. Double-click First Color. The Select First Color in Range window appears. 5. Select a color from which you want the color range to start. 6. Click OK. 7. Double-click Last Color. 8. The Select Last Color in Range window appears. 9. Select a color at which you want the color range to end. 10. Click OK. 11. Click Interpolate. The color bar below First Color and Last Color displays the new color range. 12. In the Histogram area, slide the markers or specify the values in the Min X and Max X boxes to define the section to which you want to apply the color range. 13. If required, go back to the color bar and slide its markers to narrow or widen the color range. You can also specify the values of the range in the Left Marker and Right Marker boxes. The color tabs of the histogram left and right markers change color accordingly. 14. Click one of the following options from the Values Outside Range list in the Setup Preview of New PCT section: Set to Black, which blackens the area of the histogram that is outside the specified range Set to White, which whitens the area of the histogram that is outside the specified range Ignore, which retains the original color of the histogram outside the specified range 15. Click Compress. The histogram reflects the new color range. The color bar below Compress changes to reflect the new color range and the option specified in the Values Outside Range list. The specified pseudo color range is rendered to the specified pixel values of the active raster. Opening the Raster Editing dialog box You can replace the pixel values in an image with a value of your choice. After you have set a value in the Raster Editing dialog box, you can use the New Shapes tool to 243

246 edit the raster (see Adding points to an active layer on page 303 ). 1. On the Editing toolbar, click the Raster Editing tool. Specifying a value 1. In the Pixel value box, type the value that you want to use. 2. In the Pixel value box, type the value that you want to use. If you want to replace all the pixel values within the polygon instead of just drawing the outline of the polygon, select the Fill polygon check box. 3. In the Line width box, type a value that represents the thickness of the line in pixels. Click OK. Changing a default enhancement Images can be processed at several levels, from standard enhancements that filter images with a single mouse click to fully customized enhancements using LUTs and histograms. Original image files can be difficult to visually understand. Enhancements make imagery clear and easier to interpret. When you open an image file in Focus, it is automatically enhanced in the view pane. You can change the default enhancement. (See Setting options and preferences on page 101 ) Changing Default Enhancements You can remove the default enhancement from the Raster toolbar by clicking the Enhancements arrow and choosing None. The enhancement is removed, and the view pane shows the image with no enhancement. You can also change the enhancement that is automatically applied to imagery when you open new files. 1. From the Tools menu, click Options. 2. In the Options dialog box, select Layers. 3. In the Rasters area, choose a default enhancement from the Default visual enhancement list box. 4. Click OK. There are three methods for enhancing images with Focus. For quick adjustments to your image data, you can use the Raster toolbar command buttons or the shortcut menu in the Focus Maps tree. For more detailed custom enhancements you can use the LUT Editor. The image enhancement is only applied through your system memory and must be saved if you want to use a particular LUT again or if you want to export the enhanced image. Applying a linear enhancement There are several commands on the Raster toolbar for enhancing and adjusting the appearance of your images quickly. The Raster toolbar includes contrast and brightness controls along with a list of standard enhancements, such as Linear, Root, Adaptive, Equalization, and Infrequency. The following enhancements are available from the Raster toolbar: None 244

247 Removes all enhancements and displays the original uncorrected image. Linear Improves the overall contrast of an image by stretching the minimum and maximum values in the image uniformly over the entire available dynamic range. This enhancement is best applied to images that have a normal distribution of digital number (DN) values. Root Applies a square root enhancement, which compresses higher DN values in an image and disproportionately expands the darker values. Original darker values in the image are given more contrast than the original bright (high-dn) values. Adaptive Applies an optimal enhancement curve, which is an adaptive derivative of an image histogram. Equalization Applies a histogram equalization enhancement. Infrequency Applies an infrequency enhancement, which maps gray levels based on frequency of occurrence. The Linear stretch enhancement improves the overall contrast of an image by stretching the minimum and maximum values in the image over the entire available dynamic range. 1. On the Raster toolbar, click the Enhancements arrow and choose Linear. Zooming an image feature with an enhancement 1. In the view pane, click on or near the feature you want to zoom. 2. On the Zoom toolbar, click the Zoom 1:1 Image Resolution button. Note: When an image overview is set in the view pane, all image statistics are used to calculate the enhancement. When an image is zoomed, apply the enhancement again. Focus uses the statistics of the zoomed image to calculate the new enhancement. Image Enhancements and Image Statistics: Digital numbers in images from the same sensor can vary because of land cover or environmental changes in the scene. Enhancements are based on statistics from each image. Therefore, the effects of an enhancement can vary in different images taken from the same sensor. For example, RADARSAT images are stored in 16-bit unsigned channels supporting a dynamic range from zero to 65,535 digital numbers. The usable image values in the radarsat.pix file are zero to 30,000 digital numbers. The image appears dark, with no enhancement, because 245

248 it uses less than half of the available range. When Focus collects statistics for applying an enhancement, the Tail Trim option omits the upper and lower 2% of the image histogram. Adjusting toolbar enhancements You can control how Focus computes each of the standard enhancements before they are applied to an image by adjusting the tail trim options from the Raster toolbar. Applying the Tail Trim option The pixel values for the image are averaged out over the dynamic range but the first 2% and the last 2% of values are omitted from the enhancement computation. You can also adjust the amount of tail trim from the enhancements command list from 1% to 5%. On the Raster toolbar, click the Enhancements arrow and click Tail Trim. A check mark next to Tail Trim indicates the option has been enabled. Adjusting the amount of Tail Trim 1. On the Raster toolbar, click the Enhancements arrow and click Set Trim%. 2. Choose a number that represents the percentage of tail trim. The enhancement must be re-applied to the new view pane. Exclude Min/Max If this option is enabled, the minimum and maximum values are not used as end points when applying the enhancement. The table below shows a simple pix file with only 7 pixels and 1 line. When the Exclude Min/Max option is enabled, the lowest and highest digital number (DN) values (excluding the outliers 0 and 255) are stretched to 0 and 255. When the Exclude Min/Max option is disabled, the original minimum and maximum values are used as anchors. The remaining values are stretched with respect to this range. Table 10. Pixel # of line 1 Raw Data DN Enhanced DN Exclude Min/Max Enhanced DN Include Min/Max

249 Decreasing the image contrast Interpreting image data is often simplified by adjusting the image contrast and brightness. You can increase or decrease the image contrast and brightness with the Raster toolbar controls. To increase the image contrast, click the Contrast button on the Raster toolbar. 1. On the Raster toolbar, click the Contrasts arrow and choose Decrease. You can see an approximate 10% change in the image contrast each time you click the Contrast button. You can also return the contrast level to the original enhancement before the contrast was changed by choosing the Reset option. The Brightness tool lets you increase, decrease, or reset the image brightness. To increase the image brightness, click the Brightness button on the Raster toolbar. Each click changes the image brightness by approximately 10%. Decreasing the image brightness 1. On the Raster toolbar, click the Brightness arrow and choose Decrease. You can also choose Reset to return to the original the brightness level. Enhancing images from the shortcut menu You can also apply image enhancements with the shortcut menu in the Maps tree. The same image enhancement commands in the Raster Toolbar are found in the shortcut menu. 1. In the Maps tree, right-click a data file layer and click Enhance. 2. Choose an enhancement. Opening the LUT editor Focus allows you to create custom enhancements of 8-bit, 16-bit, and 32-bit rasters. Using the LUT Editor, you can create enhancements by directly tracing or editing the histogram of the active raster. You can also compare the same histogram using different enhancements, and change the minimum and maximum values within the bit depth and x-axis ranges. 1. In the Maps tree, right-click the active layer. 2. Select Enhance and then select Edit LUTs. The Multi Histogram Display window appears if an RGB map layer is selected, otherwise, the Histogram Display window appears. 3. Click a histogram. The LUT Editor appears. The Min X and Max X values mark the boundaries of the graph along the x-axis. These values change accordingly when you manually change them or slide the x-axis level 247

250 markers. The Min LUT (X) and Max LUT (X) values encompass the range that marks the bit depth of the image. These values can change when you manually change them or slide the y-axis level markers. Displaying a histogram in the LUT Editor Focus allows you to display the input and output versions of the histogram that you want to edit in the LUT Editor. You can also display the breakpoints that can be used to edit the histogram. The changes made to the breakpoints are reflected in the ouput. 1. In the LUT Editor, select one of the following options from the Mask list box: Entire raster: displays a histogram of the entire raster. Current view area: displays a histogram of the area that is displayed in the Focus viewer. Bitmap layer: displays a histogram of a region under a bitmap mask. The bitmaps are listed whether they are saved or not. Both the file and layer names are displayed for the saved bitmaps. 2. From the View menu, select or cancel the selection of the following options: Input Histogram: displays the original version of the histogram. Output Histogram: displays the resulting histogram after enhancements Breakpoints: displays nodes, which facilitate the enhancement process Moving an entire histogram You can move the entire histogram to the right or left of the x-axis boundaries to change the range. In the graph area, right-click and drag the entire graph to the left or to the right. Using the LUT tools You can undo edits and compare different versions of a histogram for the same image data using the tools on the LUT Editor. When the LUT Editor is opened, Focus stores a copy of the histogram as a smaller version and displays it to the right of the LUT editor in the preview window. When you make changes, you can switch between the previous and the edited LUT using the Toggle option. You can also copy the edited LUT and save it as a temporary backup. Using the LUT enhancement options Enhancements are applied to values within the bounds defined by the x-axis and y-axis markers. The vertical markers set the minimum and maximum output grayscale values. The horizontal markers set the range of input grayscale values for an enhancement. 248

251 To allow tail trimming, enable the Tail Trim check box. In the Tail Trimming list box, select the tail trim percent from 1 to 5. You can also enable the Exclude Min./Max check box and enter values in the appropriate boxes. Once you apply an enhancement, you can customize it. The view with the changes in the histogram panel is automatically updated. Trace-editing a LUT histogram You can use the LUT Editor to create custom enhancements by directly editing the red histogram in the LUT graph. You can trace the general contours of a histogram. Focus redraws the image in the view pane. 1. In the LUT Editor, click the Manual Mode button in the Graph editing tools area. 2. In the graph area, drag a contour. Comparing custom enhancements You can create different custom enhancements and switch between the preview window and the LUT Editor using the Copy and Toggle options on the LUT Editor. 1. In the LUT Editor, click the Manual Mode button in the Graph editing tools area. 2. Create a custom enhancement by trace-editing the histogram. 3. Click Copy. 4. Create a new trace-edit enhancement or click on one of the enhancements to the right of the main graph. 5. Click Toggle. You can also edit the LUT directly in a spreadsheet-style dialog box by selecting Edit Table from the Graph editing tools. To open the LUT for a histogram, click Edit Table in the Graph editing tools area. Some of the other graph editing tools include: Add Breakpoint, Move Breakpoint, and Delete Breakpoint. These options let you edit the LUT for a specific location on the original image histogram. To show the breakpoints on the curve from the view option list, choose Breakpoints. The Thin Breakpoints option removes excess breakpoints along straight stretches that are associated with a LUT. Applying a new look-up table to the corresponding image plane In the LUT, you can view both breakpoints and look-up values. 1. In the Graph editing tools area, click the Edit Table button. 2. In the Lookup Table dialog box, enable the View Lookup Values check box. 3. View the breakpoints in the Breakpoints table. The values for X and Y where Y = LUT (X). The value of Y is a function of the value of X in terms of both the position of X in the LUT graph and in terms of the mathematical function that is currently applied. 4. In the LUT Editor, click Close. 249

252 Working with spatial filters Coherent signal scattering in SAR data often causes image speckles or salt and pepper effects. Speckling is inherent in most images and can inhibit accurate image interpretation. There are several image filters in Focus to help manage image speckling. Filters can enhance or subdue the details of an image. They can also be adjusted to sharpen, smooth, or detect hidden edges that are present in an image but not immediately visible. You can use the low-pass and high-pass filters to reduce graininess and highlight edge details in images. There are also specialized filters that you can use to reduce sensor noise and to clean up radar imagery. Filter computations are based on pixel samples drawn from a moving sample set, referred to as the kernel. The Kernel samples the image pixels and applies the filter to the center pixel in the sample. Once the filter is applied to the first sample, the kernel moves one pixel to the right and re-applies the filter until the entire image has been sampled. The kernel dimensions, measured in pixels, must always be an odd number; for example, 3x3 or 11x15. When the entire image has been sampled, Focus applies the changes to the entire image in the view pane. (See Opening the Filter dialog box on page 250 ) Opening the Filter dialog box The Filter dialog box lets you apply high-pass, low-pass, and custom filters. You can control the X and Y dimensions of the kernel in the Filter Size boxes. You can work with different filter types. 1. Select an image layer in the Maps tree. 2. From the Layer menu, click Filter. Filtering under a mask: You can apply the filters to all the data in the layer or you can create a bitmap mask to restrict the filtering process to a particular area in the layer. See Filtering under a mask on page 251. Low Pass Tab: Low-pass filters pass only the low-frequency information or the gradual gray-level changes. They produce images that appear smooth or blurred when compared to the original data. Click the Low Pass tab to work with low-pass filters. See Using low-pass filters on page 251. Speckle Filters: Also called adaptive filters, speckle filters are used with radar imagery to provide low-pass filtering. Speckle filters remove radar noise while maintaining high-pass information, such as edges. You can work with speckle filters under the Low Pass tab. (See Using low-pass filters on page 251 ) High Pass Tab: Pass only the high-frequency information or the abrupt 250

253 gray-level changes. The high-frequency image contains all of the local details of the image, such as object edges. Click the High Pass tab to work with high-pass filters. (See Using high-pass filters on page 254 ) Custom Tab: Lets you design your own filter. You can specify the coefficients for a filter template, regardless of the actual coefficients. Custom filters perform spatial filtering on each pixel in an image using the gray-level values in either a square or a rectangular kernel. You create custom filters under the Custom tab. (See Creating custom filters on page 256 ) Filtering under a mask You can create a bitmap mask to restrict the filtering process to a particular area in the layer. 1. In the Maps tree, create a bitmap layer. See Creating a new bitmap layer on page On the bitmap layer, use the New Shapes tool set to draw shapes over the areas that you want to filter. See Adding points to an active layer on page From the main menu, click Layer and then click Filter. For more information, refer to Opening the Filter dialog box on page From the Mask list box in the Filter dialog box, select the bitmap layer that contains the mask. The Mask list box displays all of the bitmap layers that are in the current area. The bitmap layers are listed whether they are saved or not. For each saved bitmap, both the file and layer names are displayed. 5. If you want to display or save the results for the mask area only, enable the Output only mask area check box. The data that is not covered by the mask is set to the No Data value and is not saved in the output file. Using low-pass filters Low-pass filters pass only the low-frequency information or the gradual gray-level changes. They produce images that appear smooth or blurred when compared to the original data. For non-radar image data, the following low-pass filters are available: Average Filter smooths the image data to eliminate noise. A 3x3 filter kernel computes the sum of all pixels in the filter kernel and divides the sum by the total number of pixels in the kernel. Median Filter also smooths your image data, but computes the median values within a rectangular filter window surrounding each pixel. This has the effect of smoothing the image 251

254 and preserving edges. In a 3x3 kernel, the median filter finds the median pixel value, the middle value in an ordered set, where an equal number of values are below and above the median. For example, 8 is the median value for the following 3x3 kernel in a gray-level values set: Mode Filter computes the mode of the gray-level values that occur most frequently in the filter kernel. For example, in a 3x3 filter window with the following pixel values, the filtered pixel value of 3 occurs five times. The mode filter is calculated as follows: Mode filters are typically used to clean up thematic maps for presentation purposes. This filter replaces small island themes with their larger surrounding themes. With the mode filter, the maximum kernel size is 7x7. The filter window can be rectangular. Sometimes, two values can be equally distributed within the kernel sample. In such cases, if the center value is one of the competing values, it becomes the kernel sample value. If not, the first instance of the competing values becomes the sample value. For example, in a 3x3 filter window with the following pixel values, the pixel values 3 and 5 each occur three times. In this case the Mode pixel of the filter kernel is calculated as follows: Neither 3 nor 5 is at the center of the kernel. The 5 in the top row is encountered first and therefore becomes the mode value. 1. In the Filter dialog box, enter an X- and Y-filter kernel size in the Filter size spin boxes. The larger the kernel size, the smoother (more blurred) the image. 2. Click the Low Pass tab. 3. Enable one of the following filter options: Average Median Mode 4. Click Apply to View. The filter is applied to the image in the view pane only. If you want to adjust a filter or change to a different one, click Remove View Filter. Note: Image filters are not cumulative. Each filter is applied to the original data stored in the image file. Using Gamma filters: Most image files contain some type of high-frequency 252

255 noise (speckling). While a low-pass filter reduces image speckles, it can also degrade some of the finer detail in the image. Special low-pass filters, called Gamma filters, can preserve image details by filtering on individual pixels in an image using the gray-level values in a square window surrounding each pixel. You can apply a speckle filter to preserve some of the linear features in the image. Gamma filtering is primarily used on radar data to remove high-frequency speckle, while preserving high-frequency features (edges). The input for the number of looks of the radar image is used to calculate the noise variance. You can specify an intensity or amplitude formate for the radar image. The dimensions of a Gamma filter must be odd-numbered and can be from 3x3 to 11x11 pixels. Filter size greatly affects the quality of processed images. If a filter is too small, the noise filtering algorithm is not effective; if a filter is too large, subtle details of the image will be lost in the filtering process. A 7x7 filter usually gives the best result. All pixels are filtered. In order to filter pixels located near edges of an image, edge pixels are replicated to give sufficient data. For example: Table 11. a1 a2 a3 a4 a5 a6 a7 a8 a9 In a 3x3 filter window Algorithm: The resulting gray-level value R for the smoothed pixel is: R = I for Ci less than or equal to CuR = (B*I + SQRT(D))/(2*ALFA) for Cu < Ci < CmaxR = CP for Ci greater than or equal to Cmax where: NLOOK = number of looksvar = variance in filter windowcp = center pixel gray-level valuei = mean gray-level in the filter windowcu = 1/SQRT(NLOOK)Ci = SQRT(VAR)/ICmax = SQRT(2)*CuALFA = (1 + Cu**2)/(Ci**2 - Cu**2)B = ALFA - NLOOK - 1D = I*I*B*B + 4*ALFA*NLOOK*I*CP For the amplitude image, each gray level will be squared before applying the algorithm, and the square root of the calculated pixel is returned as the final result. Applying a gamma filter 1. In the Filter dialog box, enter an X- and Y-filter kernel size in the Filter size spin boxes. Use the mode-value information for an image to set up a Gamma filter. 2. Click the Low Pass tab. 3. Enable the Gamma filter option. 253

256 4. In the Number of Looks box, enter a value that represents the number of noise-variation calculations of the radar image that you want to use. 5. In the Image Format list box, choose one of the following: Amplitude Power DB 6. Click Apply to View. If the filtered image is hard to see at your current resolution, you can zoom the image to see the filter effects. The Gamma filter suppresses the image speckles, while the linear details are preserved. Note: You must enter correct image mode values for the image data files you are working with. The number of looks and the image amplitude information is available in the format definition included with your data. (See Using high-pass filters on page 254 andsaving a filtered image to a new file on page 257 ) Using high-pass filters High-pass filters emphasize border pixels between contrasting areas and are often referred to as edge detectors. Like speckle filters, they highlight pixel contrasts associated with linear features and edge details. You can apply a high-pass filter to highlight pixel contrasts associated with linear features and edge details. Gaussian Filter (SIGMSQ = 4) is used as a band-pass filter to blur an image. This filter uses the following Gaussian function to compute the filter weights: G (i, j) = exp ( -((i-u)**2 + (j-v)**2) / (2 * SIGSMQ) ) where (i, j) is a pixel within the filter window, (u, v) is the center for the filter window, and SIGMSQ is set to 4. The filter weights W(i, j) are the normalized values of G(i, j) over the entire filter window; therefore, the sum of all weights is 1. The gray level of a filtered pixel is the sum of W(i, j) *V(i, j) over all pixels in the filter window, where V(i, j) is the original value at location (i, j). Note: In order to filter pixels located near the edges of the image, edge pixel values are replicated to give sufficient data. Laplacian Edge Detector Filters generate sharp edge definition of an image. These filters can be used to highlight edges that have both positive and negative brightness slopes. The two Laplacian filters have different weight arrangements, as shown below: Table 12. Type 1 Type 2 254

257 where the sum of all weights = 0 Example of 3x3 Laplacian filters Note: In order to filter pixels located near the edges of the image, edge pixel values are replicated to give sufficient data. Sobel Edge Detector Filter creates an image where edges (sharp changes in gray-level values) are shown. Only a 3x3 filter size can be used with this filter. This filter uses two 3x3 templates to calculate the Sobel gradient as shown below: Table X Templates Table 14. Y window Apply the templates to a 3x3 filter window. X = -1*a1 + 1*a3-2*a4 + 2*a6-1*a7 + 1*a9 Y = 1*a1 + 2*a2 + 1*a3-1*a7-2*a8-1*a9 Sobel Gradient = sqrt (X*X + Y*Y) Note: In order to filter pixels located near the edges of the image, edge pixel values are replicated to give sufficient data. Prewitt Edge Detector Filter creates an image where edges (sharp changes in gray-level values) are shown. Only a 3x3 filter size can be used with this filter. This filter uses two 3x3 templates to calculated the Prewitt gradient value, as shown below: Table X Y a1 a2 a3 a4 a5 a6 a7 a8 a9 3x3 filter window where a1 - a9 are gray levels of each pixel in the filter Templates Table

258 a1 a2 a3 a4 a5 a6 a7 a8 a9 3x3 filter window where a1 - a9 are gray levels of each pixel in the filter window Apply the templates to a 3x3 filter window. X = -1*a1 + 1*a3-1*a4 + 1*a6-1*a7 + 1*a9 Y = 1*a1 + 1*a2 + 1*a3-1*a7-1*a8-1*a9 Prewitt Gradient = sqrt (X*X + Y*Y) Note: In order to filter pixels located near the edges of the image, edge pixel values are replicated to give sufficient data. Edge Sharpening Filter uses a subtractive smoothing method to sharpen an image. First, an average filter is applied to the image. The averaged image retains all low-spatial frequency information, but has its high-frequency features, such as edges and lines, attenuated. Consequently, the averaged image is subtracted from its original image and the resultant difference image will primarily have the edges and lines remaining. After the edges are deternimed in this manner, the difference image is added back to the original image to give an edge-enhanced image. The resultant image will have clearer high-frequency detail; however, there is a tendency for noise to be enhanced. Note: In order to filter pixels located near the edges of the image, edge pixel values are replicated to give sufficient data. 1. In the Maps tree, right-click an image layer and click Filter. 2. In the Filter dialog box, enter an X- and Y-filter kernel size in the Filter size spin boxes. 3. Click the High Pass tab. 4. Enable a filter option. 5. Click Apply to View. The high-pass filter changes the image in the view pane. You can save a filter view by clicking Apply to File. The Save New Filtered Image Layer dialog box opens. You can either save the filtered image to a new image layer, or overwrite the existing layer. (See Creating custom filters on page 256 andsaving a filtered image to a new file on page 257 ) Creating custom filters You can design your own filter by specifying the coefficients for a filter template. Custom filters perform spatial filtering on each pixel in an image using the gray-level values from either a square or a rectangular kernel surrounding each pixel. Some common custom filters are Weighted average Directional Center weighted 256

259 1. Click the Custom tab. 2. Enter your filter parameters in the matrix provided. For example, for a 3x3 filter you can use a1 a2 a3, a4 a5 a6, or a7 a8 a9, and so on. When you enter a range of a1 - a9, the filter is placed over the image so that the target pixel is covered by a5. The neighbourhood pixels are then multiplied by the corresponding values in the filter and then summed. The pixel at a5 is replaced by this sum. 3. To read a kernel from a specific file, click Import. The number of entries in the first line of the file determines the number of columns in the kernel. All lines of data that follow have the same number of entries. If there are more, they are ignored. If there are less, then zeros are used to make up the difference. Data entries should be separated by spaces, tabs, or new lines. 4. To write a kernel to a file, click Export. 5. Click Normalize. The Normalize button divides all entries by the sum of the kernel entries. All other filtering algorithms normalize their respective kernels before performing the filtering operation. You can reset kernel entries to zero by clicking Reset. (See Saving a filtered image to a new file on page 257 ) Saving a filtered image to a new file Save New Filtered Image is used to select where the output of the applied filter should be saved. A file and channel must be specified for each color element composing the filtered layer: three for RGB layers and one for grayscale and PCT layers. 1. From the Filter dialog box, click Apply to File. 2. In the Save New Filtered Image dialog box, choose a file from the File list box. If a file is not listed, click Browse, locate and select it, and click Open. 3. Choose a layer from the Layer list box. If you want to create a new layer, choose New Layer and enable the Load filtered layer check box. 4. Repeat steps step 2 and step 3 for the remaining channels. 5. Click OK. Scaling images Remote sensing data is structured in 8-bit, 16-bit, and 32-bit formats. There are many instances where you may need to scale data from a higher to a lower bit depth. For example, you can prepare data for visual display by scaling it from 16-bit or 32-bit to 8-bit. You can also scale data to a lower bit depth before you export it to applications that do not support data bits greater than 8. Scaling will let you change 32-bit real data from a real number to a whole number and you can scale to reduce the size of your imagery. However, there is a risk of losing information when you scale to reduce file size. 257

260 Image Data and Scaling For 8-bit data, the digital numbers (DN) assigned to each pixel are between zero and 255. For 16-bit data, DNs can fall between zero and 65,535. Because eyes are not sensitive to subtle differences in grayscale or color, we cannot visually benefit from images composed of thousands of shade variations. Focus can also perform color and shade scaling to help you control a large range of data values. Scaling an image often makes the data easier to manage and interpret. Scaling output data using Save As The Save As dialog box lets you scale data to a new bit depth while letting you preserve the original version. Scaling data is a two-part process. Once a destination folder for your output is chosen, you can choose available GDB options in the GDB Options Editor. You then select the bit depth for the scaled output by applying new properties. Using the Output Layer Properties panel, you can choose the layer you want to scale, set your output to 8- bit, 16-bit, or 32- bit, and choose a scaling method. 1. From the Maps tree, right-click the layer you want to scale and click Save As. 2. In the Save As dialog box, choose a file from the File list box. If an output file is not listed, click Browse, locate and select it, and click Save. 3. Choose a format from the Format list box. If you want to reconfigure a format, click Options and make any changes in the GDB Options Editor. 4. Click Properties. 5. In the Output Layer Properties dialog box, choose a bit-depth for your output from the Output type list box. 6. Choose a scaling method for your output from the Scaling list box. 7. Click OK. Available scaling methods LIN: The linear function scales data values equally from the input range to the output range. Other non-linear functions also perform compression and/or stretching. SQR: The square function compresses the lower end of spectrum and stretches the upper end. The image gray levels are shifted towards the lower end so the image appears darker in comparison to the linearly scaled result. ROOT, LOG: The logarithmic and square root functions compress the upper end. The square root is stronger than logarithmic, so the image is made brighter. 258

261 NQ: The automatic normalized quantization method transforms a typical input image of a unimodal histogram into a near-symmetric, Gaussian-like distribution with the median input level transformed to the mid-point of the output range. The algorithm applies a smooth nonlinear function to gradually compress the extreme high or low portions of input range. The middle portion of the data range is mapped with little distortion. This method is recommended for image quantization to a lower number of gray levels. It is robust in handling 32-bit input images. EQ: The equal-area quantization method maps an image to the output range with an equalized output histogram. For example, each output level has approximately the same number of pixels. POW: The general power function fine-tunes the amount of compression and shifting each way with a user-supplied exponent value. If the exponent is greater than 1, the effect is shifting down; if the exponent is less than 1, the effect is shifting up. For both the input and output the entire range of digital numbers (DN) is used in determining the range. Using the Save As feature may be appropriate for scaling to 8-bit data, but situations may arise where you need control of the input and output range. If this is the case, you must use the SCALE algorithm in the Algorithm Library. Scaling output data A SCALE algorithm is available in the Algorithm Library. In some cases, you may want to use the SCALE algorithm instead of the Save As method, as it gives you more control when scaling an image by allowing you to specify your input minimum and maximum and your output minimum and maximum values. Additionally, you will be able to specify the left and right tail trimming, the scaling function, and the bit depth for the output layer. SCALE maps the gray levels of an input image to the gray levels of an output image. The typical use of this program is to scale/quantize imagery in a high-resolution (32-bit or 16-bit) channel down to a fewer number of gray levels to fit into a low-resolution (16-bit or 8-bit) channel. SCALE can also be used to stretch or shift the dynamic range of an input image for visual enhancement. If you have a Geomatica Prime license, you can use the SCALE program in the Algorithm Library. Minimum and Maximum Input Gray Level Values: If Minimum Input Gray Level Value and Maximum Input Gray Level Value are set as the default, the SCALE algorithm calculates the range from the image data based on the tail-trimming levels. If the number of input channels is greater than one and both Minimum Input Gray Level Value and Maximum 259

262 Input Gray Level Value are specified, this range is used for every input channel. Tail Trimming: Optionally specifies the amount of tail trimming of input image histogram before scaling. If Minimum Input Gray Level Value and Maximum Input Gray Level Value are specified, the specified input range is used, while Left Tail Trimming% and Right Tail Trimming% are ignored. If the two trimming parameters are not specified, the minimum and maximum of image data for every input channel is used for input range. The two trimming parameters are useful only for scaling algorithms (LIN/SQR/LOG). The two quantization algorithms squeeze tails automatically. Minimum and Maximum Output Gray Level Value: Specifies the minimum and maximum output gray-level values after scaling. If the number of channels is greater than one, the values are used for every output channel. Scaling Function: Specifies the scaling function or quantization algorithm. The following scaling functions are available #d289e3_id on page 258 Linear. #d289e3_id on page 258 Square. #d289e3_id on page 258 Square root and Logarithmic. #d289e3_id on page 258 Power with a specified exponent as defined by Exponent. #d289e3_id on page 258 Automatic normalized quantization #d289e3_id on page 258 Equal-area quantization Output Type: Specifies the sub-data type of one or more resulting images. 8-bit unsigned 16-bit signed 16-bit unsigned 32-bit real 1. Open SCALE from the Algorithm Library. 2. Select one or more raster layers for scaling. 3. Fill in the input parameters for the file. 4. Run SCALE. 5. Right-click the new layer and click Save. Fusing image data There are two algorithms you can run from the Algorithm Library that can fuse different data files into a new file. The Raster Calculator lets you work with raster data in the spectral domain, while providing indices such as the NDVI Leaf Area Index. This section provides information on using the Raster Calculator tool, the IHS-FUSE, and the PANSHARP algorithms. Running the FUSE algorithm Intensity/Hue/Saturation-FUSE performs data fusion of an input RGB color image on an input file with a 260

263 black-and-white intensity image The result is an output RGB color image with the same resolution as the intensity image. If the input and output files are different, the input RGB color image is resampled using the specified resampling method. Either the Hexcone or Cylinder IHS color model is used for data fusion. IHS converts red, green, and blue image channels to intensity, hue, and saturation image channels, which enhances and controls the output colors for a given set of input red/green/blue imagery. CYLINDER was the original method used by the IHS and RGB programs in previous PCI software releases (Version and earlier). The Hexcone model is used by many commercial image processing software programs. One model can produce more visually pleasing results than the other, depending on the circumstances. The Hexcone model runs about 15% faster than the Cylinder model. Running FUSE is similar to running IHS and RGB. IHS separates an RGB channel into three color space components (intensity, hue, and saturation) and places each in a separate channel. The RGB program can then be used to convert intensity, hue, and saturation channel output by IHS back to red, green, and blue channels. The IHS and RGB programs can enhance and control the output colors more easily for any three channels in an image database file. In computer imaging, colors are produced as combinations of the additive primary colors (red, green, and blue). Another means of color definition is in terms of intensity, hue, and saturation. Intensity is the lightness or darkness of a color. For example, in an axis that is equidistant from the three primary color axes, which are orthogonal or perpendicular to each other, zero intensity represents black. As the intensity is increased, the lightness increases and the darkness decreases. Full intensity (for 8-bit data, this is 255) represents white. Hue refers to an actual color and is defined as an angle on a circle that is centered and perpendicular to the intensity axis. For the Hexcone model, zero degrees represents red and hue values cycle through Red-Green-Blue-Red; whereas, in the Cylinder model, zero degrees represents blue and hue values cycle in the opposite direction through Blue-Green-Red-Blue. The following table shows the unscaled and scaled hue values for both IHS models: Table 17. Hue Angle Hexcone Unscaled Model Scaled Cylinder Unscaled Red Yellow Green Cyan Model Scaled Blue or or 255 Magenta Red

264 Saturation is the amount of color present or the radius of the circle described by the hue. Zero saturation represents no color and would appear as a gray shade depending on the associated intensity; full saturation (1.0 for unscaled Hexcone model or for 8-bit unscaled Cylinder model) represents full color. Full saturation accentuates the RGB components at the expense of other hues, in that other hues peak in their saturation at less than the maximum possible saturation. IHS is an easier means of controlling the output color than RGB. For example, it is easier to comprehend lightening an image (increasing the intensity) or adding more color (increasing the saturation) than it is to comprehend the effects of increasing or decreasing the RGB values. One possible application of IHS is to produce channels from three input channels, stretch the saturation channel, and then convert the IHS channel data back to the equivalent RGB channels for video display. The output image would have a better saturation range without changing the colors of the original image. The following diagram shows the geometric relationship between the RGB and IHS coordinate systems for representing color. The hexcone or cylinder is oriented so that the angles between the Intensity axis and the primary RGB color axes are the same. The Saturation axis is perpendicular to the Intensity axis. Hue is the angle between the radius of the circle defined by the RGB value and the Saturation axis. Geometric relationship between RGB and IHS 1. With a multispectral and panchromatic images open, open the Algorithm Library, and locate and double-click FUSE. 2. Select the panchromatic image layer as input to the Intensity Layer. 3. Select the multispectral image layers as input into the Red, Green, and Blue image layers. 4. Click the Input Params 1 tab and choose a type of resampling you want to use from the Resample Mode list box. 5. Choose a model from the IHS Model list box. 6. Click Run. An advantage of running IHS and RGB instead of only 262

265 running FUSE is that you can enhance the output from IHS individually, and then use the enhanced output in RGB. Running IHS and RGB 1. With multispectral and panchromatic images open, open the Algorithm Library, and locate and double-click IHS. 2. Select three image layers from your multispectral file for the red, green, and blue input layers. 3. Click the Input Params 1 tab and choose a type of resampling you want to use from the Resample Mode list box. 4. Click Run. 5. Open the Algorithm Library, and locate and double-click RGB. 6. Select a high-resolution panchromatic image layer as input for the intensity layer. 7. Select hue and saturation outputs from IHS as the inputs for the hue and saturation input layers. 8. Click the Input Params 1 tab and choose a type of resampling you want to use from the Resample Mode list box. 9. Specify the output bit depth. 10. Click Run. Using the PANSHARP algorithm PANSHARP fuses high-resolution panchromatic imagery with multispectral imagery, creating a high-resolution color image. This technique is often referred to as pan-sharpening. This program was designed to work with 8-bit, 16-bit, or 32-bit real data. Panchromatic data can be fused with multi-spectral imagery simultaneously acquired by the same sensor or with images from different sensors. The best results is achieved when the imagery is collected simultaneously and the resolutions of the panchromatic and multispectral data are closely matched. The spectral characteristics of the original data will be preserved in the resulting high resolution color imagery. This means that analysis such as classification can be done on the pan-sharpened imagery with the added benefit of higher spatial resolution. For more information, visit the PCI Web site at quickguide/pansharp.pdf. For information about orthorectifying QuickBird and IKONOS data for QuickGuides, go to: quickguide/quickbird.pdf quickguide/ikonos_help_v2.pdf Note: Landsat 7 pan and ms data is co-registered at the satellite; therefore, the geocorrection step is not necessary when using this data. 1. Ensure the panchromatic (PAN) channel and multi-spectral (MS) channels are co-registered, geo-corrected, or orthorectified. 2. Open the PAN and MS images. 3. Open the Algorithm Library, and locate and double-click PANSHARP. 263

266 4. Choose the pan image channel from the InputPan port. The input reference image channels should be selected so that the ms bands cover the frequency range of the panchromatic channel as closely as possible. The channel number given in the above table is the standard ordering on the sensor and may differ from the order in an actual data file. 5. Select the MS channels to use in the Input port. The best pan-sharpening results are obtained from MS channels whose wavelengths lie within the spectral frequency range of the pan data. 6. The output can either be sent to the viewer or can be saved to a new.pix file. Note: To avoid reducing the radiometric resolution of the data, process and save all the image bands in signed 16 bits. Testing demonstrated that 16 bits for intermediate data are enough; 32 bits are not necessary. The following is a list of the reference bands for some well-known satellite sensors: Table 18. Sensor Landsat 7 (ETM+) SPOT 1, 2, 3 Reference Bands Green 2 Red 3 Near IR: 4 Green 1 Red 2 Sensor (HRV) SPOT 5 (HRG) IRS 1C, 1D Blue 1 Green 2 Reference Bands Green 1 Red 2 IKONOS Blue 1 Green 2 Red 3 Near IR: 4 QuickBird Blue 1 Green 2 Red 3 Near IR: 4 There is only one optional parameter in the InputParams 1 tab. For a description of the No data image value parameter, see PANSHARP in the online Help. The automatic image fusion algorithm was developed by Dr. Yun Zhang from the University of New Brunswick. For more information and comparative results, see the below references: Zhang, Yun. Problems in the fusion of commercial high-resolution satellite, Landsat 7 images, and initial solutions. ISPRS, Vol. 34, Part 4, #Geospatial Theory, Processing and Applications#, Ottawa, Zhang, Yun. A new automatic approach for effectively fusing Landsat 7 and IKONOS images. IEEE/IGARSS'02, Toronto, Canada, June 24-28,

267 Using the raster calculator The Raster Calculator lets you formulate, write, and run calculations based on data associated with raster files. It provides a graphical interface where you can create expressions for working with any raster data, such as spectra data and digital elevation models (DEM). When you build an expression, either type the expression in the Expression box or build the expression by clicking the buttons and items in the dialog box. Combining the two methods may cause unwanted effects. The Raster Calculator also provides indices, such as the NDVI Leaf Area Index. You can calculate results for the simplest raster arithmetic or the most complex equations and your output can be a number, a 2D image, or both. The following table shows a list of the Raster Calculator categories and their associated functions. Table 19. Category Attribute Statistics Channel Statistics Constants Conversion Functions FieldValue - min, max, mean, sum, mode, std, median, count, first, last, wgtavg Channel - min, max, mean, sum, mode, std, median, count E, PI, 2*PI, PI/2, PI/4 Rad2Deg, Deg2Rad, Division Exponential Extreme Hyperbolic Logarithmic Random Rational Sign Category Trigonometric Special Values Variables Functions Feet2Meters, Meters2Feet Div, Mod Exp, Pow, Sq(a), Squr, Sq (a,b), hyp Min, max, round, floor, ceil Cosh, Sinh, Tanh, ACosh, ASinh, ATanh Ln, Log, Alog Rand, Seed If a = b, If a <> b, If a > b, If a < b, If a >= b, If a <= b Abs, Neg, Sgn Cos, Sin, Tan, ACos, Asign, String, integer, float, double (See About the raster calculator on page 265 ) About the raster calculator The Raster Calculator can be used in either basic or 265

268 advanced mode. Advanced mode provides more category and function options and allows you to choose from several attributes that can be used in your calculations.when you use the Raster Calculator, new output layers are added to the Focus window. Expression The Expression menu lets you start a new expression, open a saved expressions, export an expression as and EASI file (.eas), and run an expression on chosen data. New: Starts a new Expression sessions. Open: Opens saved expressions. Save: Opens the New Expression Name dialog box to save an expression. Save As: Opens the New Expression Name dialog box to either save an expression or save an expression with a new name. Export to EASI: Opens the File to Save dialog box to save an expression using the EASI file format (.eas) Run: Runs the expression you are working with on the data you have selected in the Channels and Bitmaps list. (See Channels and Bitmaps) Run and Close: Runs your expression and closes the Raster Calculator. Close Window: Closes the Raster Calculator. Edit The Edit menu lets you work with the text in the Expression area. You can undo text edits, cut, copy, paste, and delete text in your expression. Undo: Cancels the last action within the Expression area. Cut: Cuts selected text in the Expression area. Copy: 266

269 Copies the selected text in the Expression area. Paste: Pastes cut or copied text at the cursor location. Delete: Deletes selected text in the Expression area. Select All: Selects all the contents of the Expression area. View The View menu lets you choose either basic or advanced mode for the Raster Calculator. Basic: Changes the Raster Calculator to Basic mode. Advanced: Changes the Raster Calculator to Advanced mode. Raster Calculator toolbar The Raster Calculator toolbar lets you start new expressions, open saved expressions, save expressions, run expressions, and stop expression operations. New: Starts a new expression. Open: Opens the Expression name dialog box, where you can select a saved expression from a list. Save: Opens the New Expression Name box so that you can enter name for a new expression. Run: Runs the expression you have selected. Stop: Stops an expression operation. Expression The Expression area shows the numeric values and the expressions used in a calculation. You can add values and, in Advanced mode, you can add expressions by selecting a category and choosing a function. Input: Lets you choose file data and specify the layers of a file. 267

270 Browse: Opens the File Selector dialog box. Channels and Bitmaps: Lets you choose a channel or bitmap from the list for the expression. Attributes: Lists the attributes in the data. Calculator keys The Raster Calculator Keys include most standard calculator keys and numbers. In Advanced view, additional functions are available. Advanced functions are divided into 15 categories. Categories: Lets you choose a category of functions you can use in your expression. Functions: Lists the functions for the category you have chosen. Output parameters The Output parameters area lets you set the parameters for your Expression output data. Single Value: Gives a numerical output value. When you disable the check box, the Mask, Type, Display, and Save options are available. Mask: Lets you choose a bitmap mask from within your source data. Type: Lets you choose the bit depth of your output raster data. Display: Shows the output of your expression in the view pane. Save: saves the output to a selected file and layer. Display Saved Results: Opens your results in the view pane after you have run an expression. File: Lets you choose a target output file. Browse: 268

271 Opens a File Selector dialog box, where you can choose a target output file. Layer: Lets you select a target output channel. Status bar: Reports single-value results and the status of an expression. Using the Raster Calculator to set output parameters The Single Value option gives you a single-number result for a single-band computation in the status bar of the calculator tool. Display: Is the result of a computation on one or more bands that produces a band. This output field can be saved to disk and can be shown in the Focus window. 1. From the Tools menu, click Raster Calculator. 2. Click in the Expression box. 3. Using the calculator buttons, enter an equation in the Expression box and specify Add to existing file. 4. Enter an equation in the Expression box and specify Add to new file, channel description, and channel type into the output parameters. 5. Enter an equation in the Expression box that results in a single integer value. When no output parameters are specified, the Raster Calculator checks for errors in the equation (such as parentheses not closed), calculates the result, and displays it in a new window. Many of the same formatting rules for EASI Modeling apply to the Raster Calculator. (See Opening the EASI Modeling dialog box on page 269 ) Opening the EASI Modeling dialog box You can use the EASI scripting language to write scripts and run them on data you have open in Focus. You can also open the EASI Modeling dialog box to run EASI scripts for data that is not open in Focus. Dozens of pre-written scripts are available in the Geomatica V10.0 pro folder. EASI Modeling uses a single input file. The model is performed directly on the database file. It is recommended that you keep a copy of the original input file before running the model. You can also test the model using bitmaps instead of image layers, where applicable. The Modeling window provides the option of displaying the results to the view pane. It is not necessary to save this new layer back to the database, as the modeling program operates directly on the database file, rather 269

272 than the display. When you review the results on-screen, you can delete the new layer by right-clicking the layer in the Maps tree and clicking Remove. For details on numeric, string, logical, and modeling (channel, bitmap and special variable) expressions, see the EASI topic in the Geomatica Help. The online Help provides details on the entire EASI scripting language. EASI Modeling is designed primarily for simple image modeling. While all options are available for PACE MODEL scripts run at the EASI prompt, only a subset of these commands can be used in the EASI Modeling window. For more information on EASI Modeling with Geomatica, go to quickguide/easimodelinginfocus.pdf on the PCI Geomatics Web site. 1. From the File menu, click Open. 2. In the File Selector dialog box, locate and select the file on which you want to run an EASI script, and click Open. The image and bitmap layers must exist in the database.pix file prior to running the model. 3. From the Tools menu, click EASI Modeling. About the EASI Modeling dialog box The EASI Modeling dialog box allows you to view EASI Models as text. You can load and edit previously written scripts, select input data, run scripts, save scripts and script changes, and have the results opened in the view pane. Input File: Lets you select an input file from the list box. Browse: Opens the File Selector dialog box. Run: Runs the EASI script loaded in the EASI Modeling dialog box. Clear: Clears all text appearing in the EASI Modeling dialog box. Load: Opens a File Selector dialog box, where you can select pre-written or saved EASI Modeling files. Save: Saves scripts opened in the EASI Modeling dialog box. Save As: Lets you save an EASI script using another file name. Display Results: 270

273 Opens the output of the EASI script. Close: Closes the EASI Modeling dialog box. Adding image and bitmap layers to a.pix file 1. From the Files tree, right-click a file and click New and then click Image Layer (or Bitmap Layer). 2. From the Tools menu, click EASI Modeling. 3. In the EASI Modeling dialog box, from the Input File list, choose an input file from the Input File list box. 4. Click in the model box and type a model (for example, %12=(%1-%2)/(%1+%2);). If you want to display the model results in the view pane, enable the Display Result check box. 5. Click one of the following buttons: Run: executes the model Clear: clears the model box Load: opens an existing model with files using the.eas file name extension Save: saves the model to a text file using the.eas file name extension Using simple image models Modeling equations, in their simplest form, are arithmetic combinations of image layers assigned to other image layers. Image layers are indicated by a percent sign followed by the layer number. The following equation assigns the average numeric value of image layers 1 and 2 to image layer 3. %3 = (%1 +%2)/2 The assignment is evaluated for every pixel in image layer 3, using the corresponding pixel values from image layers 1 and 2. You can also assign a constant value to an entire image layer. %1 = 255 A standard set of arithmetic operations is available in modeling expressions: a + b Addition a - b Subtraction a * b Multiplication a / b Division a ^ b Exponentiation (a) Parentheses, also square brackets []. - a Unary negation The following mathematical intrinsic functions are also available: 271

274 sin(), cos(), tan(), asin(), acos(), atan(), ln(), log10(), exp(), exp10(), rad(), deg(), abs(), int(), random() and frac() All the rules previously indicated for image layers also apply to bitmap layers, except that the variables are prefixed with two percent signs instead of one. A bitmap layer can have a value of either 1 (ON) or 0 (OFF). For example, if image layer 1 has a digital number greater than 50, then set bitmap layer 15 to 1. If %1 > 50 then % %15 = 1 endif Understanding the basic modeling logic In addition to using simple assignment equations, you can also construct simple logical operations in the EASI Modeling dialog box. These operations take the form of 'IF' statements. The following command sets the numeric value of image layer 2 to 255 anywhere the value of image layer 1 is between 32 and 64. Line breaks are significant; each statement must be on its own line. if (%1 >= 32 AND %1 <= 64) then %2 = 255 endif The following example shows a more complex procedure to turn on bitmap layer 2 (%%2), where image layers 1, 2, and 3 are equal to 255. if (%1 = 255) and (%2 = 255) and (%3 = 255) then %%2 = 1 else %%2 = 0 endif The possible comparison and logical functions are: a > b a greater than b a < b a less than b a = b a equals b a <> b a not equal b a <= b a less than or equal b a >= b a greater than or equal b a OR b a is true or b is true a AND b a is true and b is true 272

275 !a a is not true You can also use brackets to ensure operations take place in the expected order. Detailed Examples In the following example, a 'Vegetative Index' calculation using image layers 1 and 2 is performed and the results are saved to image layer 13 of the same file. Next, a 32-bit real image layer is added to the sample data file irvine.pix to store the results. 1. With irvine.pix open, click the File tab. 2. Right-click irvine.pix and click New and then click Raster Layer. 3. In the Add Image Channels dialog box, enter a 1 in the 32 bit real box and click Add. 4. From the Tools menu in the Focus window, click EASI Modeling. 5. In the EASI Modeling dialog box, enter the following model in the model box: %13=(%1-%2)/(%1+%2); To output to an 8-bit image layer, some scaling and adjustment is necessary. 6. Click Run. Adding a bitmap layer to irvine.pix From the Files tree, right-click irvine.pix and click New and then click Image Bitmap Layer. To view the results in the view pane, enable the Display Results check box. if (%1 < 55) and (%2 < 55) and (%3 < 55) then %%33 = 1 else %%33 = 0 endif The demo file irvine.pix does not contain a black 'no data' area outside the image. For the purpose of the following example, a digital number of less than 55 in image layers 1, 2, and 3 was used to create the bitmap layer. If you are creating an actual mask for the 'no data' area, you use (%1 = 0) and (%2 = 0) and (%3 = 0) in the IF statement. Change area under bitmap to white in image layers 1, 2, and 3; if %%33=1 then %1=255 %2=255 %3=255 endif; Create a white grid on an RGB image: 273

276 if or then %1 = 255 %2 = 255 %3 = 255 else %1 = %1 %2 = %2 %3 = %3 endif See 'Special Variables' for details on the @sizey. Blending examples Create an image which smoothly blends image layer 1 into image layer 2 as you move across the image. The output is placed in image layer 8. %8 = ((@x-1)/@dbx)*%2 + ((@dbx-@x)/@dbx)*%1 5) Create a gray level ramp of 0 to 255 across an image layer. %8 = ((@x-1)*255) Perform a 3x3 smoothing filter on image layer 8. Back slashes are used to extend a statement over multiple lines. Also note that the Algorithm Library program FAV performs this operation more efficiently. %8 = (%4[@x-1,@y-1] + %4[@x,@y-1] + %4[@x+1,@y- 1] + \ %4[@x-1,@y ] + %4[@x,@y ] + %4[@x+1,@y ] + \ %4[@x-1,@y+1] + %4[@x,@y+1] + %4[@x+1,@y+1] ) / 9 When processing pixels on the border of the image, the neighbourhood of the current pixel extends off the database. To ensure that referenced pixels that are off the database (such as%4[@x-1,@y-1] in the top left corner) are usable, the image values are replicated out from the edge of the database to supply values that are missing. The following section describes EASI Modeling syntax in more detail. Image layer variables Image layers can be specified in a modeling expression using any of the following forms: %n [(x_expr, y_expr)] 274

277 %{ n } [(x_expr, y_expr)] %{ file_spec, n } [(x_expr, y_expr)] The first case is the image layer sign (%) followed by a literal numeric value, such as 1, 2 or 3, indicating layer 1, 2, or 3 of the implicit database (such as the input file). The second example is similar, but the image layer number may be a numeric expression that is evaluated to be the image layer number. The third case is more general yet. The file_spec may be a database file name or a file handle returned by DBOpen(), and the image layer number is evaluated as an expression(#n#). For simple models, you cannot reference files other than the input file selected from the list box. EASI Modeling generally operates on a single file for both input and output. For example, you cannot run the following model if your input file is D:\Geomatica_V82\demo\irvine.pix. %13 = %{"D:\Geomatica_V82\demo\eltoro.pix", 1} However, you can override this by using the DBOpen() function to open any number of database files. To copy image layer 1 from eltoro.pix to image layer 12 in irvine.pix: local integer fdinput, fdoutput fdinput = DBOpen("D:\Geomatica_V82\demo\eltoro.pix", "r") fdoutput = DBOpen( "D:\Geomatica_V82\demo\irvine.pix", "r+") %{fdoutput,13} = %{fdinput,1}; call DBClose(fdinput) call DBClose(fdoutput) The irvine.pix file is 512x512 and eltoro.pix is 1024x1024. The previous operation copies image layer 1 of eltoro.pix to image 13 of irvine.pix, but because irvine.pix is the implicit database (such as the input file), the area of operation is 0, 0, 512, 512; only the top left quarter of eltoro.pix is copied into channel 13 of irvine.pix. The second part of the image layer specification is an optional subscript specification. In the above case, the default subscript specification used is x --> x, y --> y. The subscript specification allows you to indicate the pixel that should be operated on for the current value of X and Y, and may be given as an expression. The following example assigns a sampled copy of eltoro.pix to irvine.pix. symbols are the current pixel location when the expression is evaluated for each pixel. local integer fdinput, fdoutput fdinput = DBOpen( "D:\Geomatica_V82\demo\eltoro.pix", "r") 275

278 fdoutput = DBOpen( "D:\Geomatica_V82\demo\irvine.pix", "r+") %{fdoutput,13} = %{fdinput,1}(@x*2+1,@y*2+1); call DBClose(fdinput) call DBClose(fdoutput) X and Y vary from 0 to 511 as the implicit window of operation is 0, 0, 512, the area of irvine.pix. However, image layer 1 of eltoro.pix is sampled for values of 1 to value from 0 to 511, the varies from 1 to It is also legal for the subscript expressions to extend of the source database. In this case image values from the edge of the database are replicated out as far as is needed to satisfy requests. Thus, a simple filter such as example 6 above the following will work in a reasonable manner, even on the edge of the database. Bitmap Layer Variables Bitmaps layers are basically one bit deep image layers, used primarily to serve as masks for regions where operations are to take place and may be specified in a manner very similar to image layers. All the rules previously indicated for image layers also apply to bitmap layers, except that the variables are prefixed with two percent characters instead of one. Also, the index number is the segment number of the bitmap layer to be used. %%n [(x_expr, y_expr)] %%{ n } [(x_expr, y_expr)] %%{ file_spec, n } [(x_expr, y_expr)] Bitmap layer variables will only assume values of zero or one. Any non-zero value assigned to a bitmap layer will be treated as one. Creating an EASI bitmap mask Create a bitmap mask (segment 2) which is true (1) everywhere channels 1 and 2 are less than 25. Then this mask and the mask in segment 3 are used to determine a region that should be zeroed in image channels 1 and 2. if (%1 < 25 and %2 < 25) then %%2 = 1 else %%2 = 0 endif if (%%2 = 1 and %%3 = 0) 276

279 then %1 = 0 %2 = 0 endif Special Variables Allow access to information about the size and georeferencing information of channels being operated on and the position of the current pixel. The following special variables may be treated as elements in modeling current x (pixel) processing current y (line) processing size of database in x (pixel) size of database in y (line) size of a pixel in x direction in size of a pixel in y direction in x georeferenced centre of current y georeferenced centre of current x size of a pixel in georeferenced y size of a pixel in georeferenced units @geox change value for each pixel @sizex remain constant over the whole image. It is usually necessary to use special variables when constructing subscript expressions for channel expressions. For example, the following assignment would mirror an image across a vertical center line. is used in computing the center line. %2 = %1[@dbx-@x+1,@y] Numeric Expressions Numeric expressions in EASI are normally operated on in double precision floating point. Values with less precision are promoted to double precision before operations are performed. A wide set of built-in operations are available in numeric expressions and are listed below with a short description. a + b Addition a - b Subtraction a * b Multiplication a / b Division 277

280 a ^ b Exponentiation ( a ) Parenthesis, also square brackets []. - a Unary negation A numeric element can be any of the following: A numeric constant. An EASI variable of type byte, int, float or double. An element of a numeric variable array. A numeric intrinsic function. A numeric user defined function. A subscripted numeric parameter. Numeric constants can be entered as decimal or scientific notation numbers with an optional negative sign. Scientific notation is denoted with the #E# or #D# character - for example can be written as 1.23e5, 1.23 * 10 ^ 5 Comparison and logical functions a > b a greater than b a < b a less than b a = b a equals b a <> b a not equal b a <= b a less than or equal b a >= b a greater than or equal b a OR b a is true or b is true a AND b a is true and b is true!a a is not true Example if (%1 = 255) and (%2 = 255) and (%3 = 255) then %%2 = 1 else %%2 = 0 endif Logical Logical expressions in EASI are used to compute TRUE/FALSE results for use with the IF and WHILE conditional statements. There is currently no way to store a pure logical value in an EASI variable. Logical expressions consist of comparisons between numeric and string expressions combined with the use of the logical operations AND, OR, and NOT. The equality and inequality tests may be used with two numeric expressions. The equal sign (#=#) is used to test for equality, while inequality is tested with #<># or #!=#. 278

281 Examples If( %1 = 0 ) then... while( flag <> 1 )... The ">", "<", ">=" and "<=" operations may only be performed on numeric expressions. Examples: while( total <= 100 ) while( total < 101 ) while( NOT total > 100 ) while( NOT total >= 101 ) The logical operations AND and OR operate on two logical expressions, while NOT operates on one logical expression. The symbols #&#, # # and #!# are considered to be equivalent to AND, OR, and NOT. Examples: if( A = 1 AND B = 1 )then... endif if( A = 1 & b = 1 )then... endif The IF statement is used to conditionally execute statements. IF( logical_expression )THEN statement_list [ELSEIF( logical_expression )THEN statement_list] [ELSE statement_list] ENDIF logical_expr - a logical expression as described in #Logical Expression.# statement_list - a list of one or more statements. Each logical_expression is evaluated in turn until one of them evaluates to be true. When one is true, the corresponding statement_list will be executed, and 279

282 control will continue beyond the ENDIF. If none of the logical expressions is true and an ELSE clause exists, the associated statement_list will be executed. The WHILE command provides a general purpose looping construct. WHILE( log_expr ) statement_list ENDWHILE log_expr - a logical expression which is evaluated before each iteration of the loop. The logical expression in the WHILE statement is evaluated. If the result is true, the statement list is executed; otherwise, control skips to the statement following the ENDWHILE. Once the statement list has been executed, control returns to the WHILE statement to test the logical expression again. It is possible to jump into, or out of, the WHILE loop using the GOTO statement, but this is poor style and may not work in future versions of EASI. The FOR command provides a simple looping construct over a series of numeric values. FOR iter_var = start_val TO end_val [BY incr_val] statement_list ENDFOR iter_var - the iteration variable. This may be any numeric variable type, including a parameter. start_val - this initial value to assign to the `iter_var'. end_val - when `iter_var' passes this value, iteration stops. incr_val - a value by which to increment `iter_var' each iteration. The default is 1. The FOR statement initializes the iteration variable to the initial value, checks it against the end value, and if the end value is not exceeded it executes the statement list. When the ENDFOR statement is reached, the iteration variable is increased by the increment value and compared to the end value. If the end value is not exceeded, the statement list is executed again. The start value may be greater than the end value and the increment value may be negative, but if the increment value does not take the iteration variable value closer to the end value each iteration, the FOR loop will never terminate. It is possible to alter the value of the iteration variable inside the FOR loop and also to use GOTO to escape or enter the loop, but this is poor style and may cause problems in future versions of EASI. Example: 280

283 The following example runs the PACE task CLR on the first 128 channels of the PCIDSK file irvine128.pix in groups of 16 channels at a time. local i,j valu = 0 File = "C:\Geomatica_V82\demo\irvine.pix"; run clr Single Statements You can split very long statements over multiple lines by placing a back slash character, not a semi-colon, at the end of each incomplete line. file="c:\geomatica_v82\demo\irvine128.pix" for i = 1 to 128 by 16 for j = 1 to 16 dboc(j) = i + j - 1 endfor run clr endfor Multiple statements can be placed on the same line by separating the statements with a statement separator. The back slash and semi-colon characters can be used interchangeable for this purpose. A line of input may be almost any length. Examples File = "C:\Geomatica_V82\demo\irvine.pix" \ run clr 281

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285 Chapter 7 Understanding atmospheric correction The data obtained by optical satellite sensors with high spatial resolution has become an invaluable tool for many groups interested in studying, managing, developing, and protecting our population, environment, and resources. Unfortunately, satellite images are often obscured by atmospheric effects like haze as a result of conditions in the atmosphere at the time the image was captured. Atmospheric correction is a process used to reduce or eliminate atmospheric effects and reveal more accurate surface reflectance values. Two atmospheric correction processes are available: ATCOR2, which is used for correcting satellite imagery over flat terrain, and ATCOR3, which is used for correcting satellite imagery over rugged terrain. Both are algorithms that work with a database of atmospheric correction functions, which are stored in lookup tables. The algorithms have been developed mainly for satellite sensors with a small swath angle such as Landsat and SPOT, but some wide field-of-view (FOV) sensors such as IRS-WiFS are supported as well. For more information on the atmospheric correction, please see the following articles: R. Richter, 'A spatially adaptive fast atmospheric correction algorithm' Int. J. Remote Sensing, Vol. 17, (1996) R. Richter, 'Atmospheric correction of satellite data with haze removal including a haze/clear transition region', Computers & Geosciences, Vol. 22, (1996) R. Richter, 'Correction of satellite imagery over mountainous terrain', Applied Optics, Vol. 37, (1998) Preparing data Before you begin setting up the atmospheric correction process, the data must be in one PCIDSK (.pix) file with all the channels in the same bit depth and resolution. Focus supports 8-bit unsigned, 16-bit unsigned, 16-bit signed, and 32-bit real bit depths. 1. Transfer the data from the CD to PCIDSK (.pix) files, see Transfer data to PCIDSK on page Reproject the thermal data, see Reprojecting data on page Assemble the data into one PCIDSK (.pix) file, see Assembling data into a file on page 285. Transfer data to PCIDSK You should import your images from the compact disk (CD) using the appropriate CD read algorithm. Each sensor has its own CD read algorithm. It creates a PCIDSK file, imports the imagery channels from the CD, 283

286 extracts the metadata, and saves the satellite path information in a segment. By preparing your imagery this way, Focus can automatically set or calculate several parameters when you configure the atmospheric correction. The number and types of bands on the CD depends on the sensor used to capture the data. Usually, the visible, thermal, and panchromatic bands are in different resolutions. Some sensors may not provide thermal or panchromatic bands. Read the bands of the same resolution at the same time into one file. For example, Landsat 7 data usually has eight bands: bands 1 to 5 and 7 are the visible wavelengths with a 30-meter resolution, band 6 contains two thermal wavelengths with a 60-meter resolution, and band 8 is the panchromatic with a 15-meter resolution. You would use the CDLAND7 algorithm to read bands 1 to 5 and 7 into a file, then band 6 into a file, and then band 8 into a file. If you do not intend to use the thermal or panchromatic bands in the atmospheric correction process, then you do not need to read those bands into a file. The CD read algorithms are available through EASI, Modeler, OrthoEngine, and Focus. 1. In the main menu, click Tools and then click Algorithm Librarian. 2. Under PCI Predefined in the Data Interchange folder, open the CD Reading/Utilities folder. 3. Click the appropriate CD read algorithm for the data. 4. Click Open. 5. Enter the required information on the Files and Input Params 1 tabs. 6. Click Run. 7. Repeat for each set of bands with the same resolution. Reprojecting data If you intend to use a thermal band in the atmospheric correction (ATCOR) process, you need to reproject it to the same resolution as the visible bands. For Landsat 7 data you can use either the high gain or low gain thermal channels with ATCOR. For ASTER data use band 13. For example, Landsat 7 thermal bands have a 60-meter resolution while its visible bands have 30-meter resolution. Therefore, the thermal bands have to be reprojected to a 30-meter resolution. 1. In the main menu, click Tools and then click Reprojection. 2. Click the Browse button beside Source file and select the file that you want to reproject. 3. In the Destination file box, type the path and file name for the reprojected data. 4. In the Output format box, click PIX:PCIDSK. 5. Under Reprojection Bounds, click Use bounds and resolution in the list. 6. In the Pixel Size boxes in the X and Y boxes, type the new resolution. 7. In the Resampling list, click the resampling method of your choice. Nearest: Nearest Neighbor resampling 284

287 identifies the gray level of the pixel closest to the specified input coordinates and assigns that value to the output coordinates. Although this method is considered the most efficient in terms of computation time, it introduces small errors in the output image. The output image may be offset spatially by up to half a pixel, which may cause the image to have a jagged appearance. Bi-Linear: Bi-linear resampling determines the gray level from the weighted average of the four closest pixels to the specified input coordinates and assigns that value to the output coordinates. This method generates an image with a smoother appearance than Nearest Neighbor resampling, but the gray level values are altered in the process, which results in blurring or loss of image resolution. Cubic: Cubic resampling determines the gray level from the weighted average of the 16 closest pixels to the specified input coordinates and assigns that value to the output coordinates. The resulting image is slightly sharper than one produced by Bi-linear resampling, and it does not have the disjointed appearance produced by Nearest Neighbor resampling. 8. Under Source Layers, click Select All. 9. Click Add. 10. Click Reproject. Assembling data into a file If you intend to use a thermal band in the atmospheric correction process, you need to add the thermal band to the file containing the visible bands. The thermal band must be in the same resolution as the visible bands. For Landsat 7 data you can use either the high gain or low gain thermal channel with ATCOR. For ASTER data use band From the Files tree, right-click the thermal channel. 2. Click Export (Save As) and click To existing file. 3. Beside Destination file click the Browse button and select the file containing the visible bands. 4. Under Source Layers, click Select All. 5. Click Add. 6. Click Transfer Layers. Opening the Atmospheric Correction Configuration dialog box Before you begin setting up the process, you should import your images from the compact disk (CD) using the appropriate CD read algorithm. For example, if you have IKONOS imagery, you would use CDIKONOS to import your images. By preparing your imagery this way, Focus can automatically set or calculate several parameters. Also, the data must be in one PCIDSK (.pix) file with all the channels in the same bit depth and resolution. For more information, see Preparing data on page 283. Once your files are prepared, you can configure the Atmospheric Correction parameters. These parameters define the image to be corrected, the source of the elevation, the sensor information, the atmospheric conditions, and other required parameters. 285

288 1. In the main menu, click Analysis. 2. Click Atmospheric Correction. Setting up atmospheric correction parameters 1. In the Image file list, type the path and file name of the file that you you want to correct or click Browse to select a file. 2. If the image represents an area of flat terrain or if you do not have a digital elevation model (DEM) for the image, click Constant(ATCOR2) and in the Height box type a value representing a constant elevation for the area covered by the image. 3. If you do have a DEM for the image, click DEM (ATCOR3). In the File box click the file that contains the DEM or click Browse to select a file. In the Layer list select the layer containing the elevation values. 4. To calculate Sky View and Shadow or to import Slope and Aspect calculations, click Setup. For more information, see Calculating slope, aspect, sky view, and shadow on page In the Units list, click the unit of measurement used for the elevation values. 6. In the Sensor type list, click the type of sensor used to collect the image. 7. If you did not use a CD read algorithm to import your images, you may need to match the sensor band numbers to the correct image channel numbers. To set up the channels, click Band Setup. For more information, see Matching band numbers to channel numbers on page In Pixel size list, type the pixel size of the input image. 9. If the date is included in the metadata, the Date boxes are set automatically. If not, in the Date boxes click the month, day, and year when the image was taken. 10. The Tilt list is available only when the sensor selected provides the tilt capability. If the sensor was tilted when the image was taken, click the title angle used in the Tilt list. If the metadata describes the tilt angle in terms of left and right, right means West and left means East. 11. In the Calibration file list click the calibration file for the image and sensor type or click Browse to select a file. In most cases you can use the file with #standard# (or std) in the file name. For more information, see Editing an existing calibration file to create a new file on page In the Atmospheric definition area list, click the aerosol type for the image. For more information see About aerosol types on page In the Condition list, click the standard atmosphere present when the image was taken. For more information see About standard atmospheres on page If you also selected a thermal band to correct, in the Thermal atmospheric definition list click the standard atmosphere present when the image was taken. For more information see About standard atmospheres on page If the date, time, and position are included in the metadata, the solar zenith value will be calculated automatically. If they are not, in the Solar zenith box type the solar zenith value or click Calculate to calculate the value (see Calculating the solar zenith and azimuth on page 290 ). 286

289 16. (Available for ATCOR3 only) If the date, time, and position are included in the metadata, the solar azimuth value will be calculated automatically. If they are not, in the Solar azimuth box type the solar azimuth value or click Calculate to calculate the value (see Calculating the solar zenith and azimuth on page 290 ). 17. In the Visibility box type the visibility value. For more information, see About visibility on page In the Adjacency box type the adjacency value. For more information, see About adjacency on page (Available for thermal bands only) In the Offset to surface temperature list, type the value used to compensate for a systematic error in the conversion of radiance values to temperature values. For more information, see Determining the offset to surface temperature value on page Click OK. About aerosol types The Atmospheric definition area list on the Atmospheric Correction Configuration dialog box (see Opening the Atmospheric Correction Configuration dialog box on page 285 ) contains the possible aerosol types for the image. The aerosol type is determined by the predominant particles present in the area at the time the image was captured, which usually can be inferred its geographic location. Wind direction and weather conditions in the area in the days before the image was taken can affect the aerosol type present. The aerosol types are: Rural: The rural aerosol type is composed mostly of dust-like and organic particles. It is predominant in continental areas whose atmosphere is not strongly influenced by urban or industrial centers. It is recommended for areas such as forested, agricultural, or snow-covered areas. Urban: The urban aerosol type is composed mostly of particles such as sulfate aerosols resulting from combustion and industrial activities. If you do not know the composition of the atmosphere, the rural aerosol type is recommended. Desert: The desert aerosol type is composed mostly of large dust-like particles. If you do not know the composition of the atmosphere, the rural aerosol type is recommended. Maritime: The maritime aerosol type is composed mostly of sea-salt, dust-like and organic particles. If you do not know the composition of the atmosphere, the rural aerosol type is recommended. About standard atmospheres The Condition list and the Thermal atmospheric definition list on the Atmospheric Correction Configuration dialog box (see Opening the Atmospheric Correction Configuration dialog box on page 285 ) contain the standard atmospheres used in Atmospheric Correction. Standard atmospheres are vertical profiles of pressure, temperature, water vapor, and ozone density. The water vapor content present in the area plays a key role in determining which standard atmosphere to select when performing an atmospheric correction. For sensors that do not include water vapor bands, you can estimate the water vapor content based on the season when the 287

290 image was captured and the location. The standard atmospheres are: Dry or Dry Desert: A dry atmosphere has a total water vapor content of 0.41 (g cm-2). Fall (spring): A fall (autumn) atmosphere has a total water vapor content of 1.14 (g cm-2). Humid: A humid atmosphere has a total water vapor content of 4.94 (g cm-2). Mid-latitude summer: A midlatitude summer atmosphere has a total water vapor content of 2.92 (g cm-2). Mid-latitude winter: A midlatitude winter atmosphere has a total water vapor content of 0.85 (g cm-2). Sub-Arctic summer: A sub-arctic summer atmosphere has a total water vapor content of 2.08 (g cm-2). Sub-Arctic winter: A sub-arctic winter atmosphere has a total water vapor content of 0.42 (g cm-2). Tropical: A tropical atmosphere has a total water vapor content of 4.11 (cm or g cm-2). Arid: An arid atmosphere has a total water vapor content of 2.15 (g cm-2). US standard: The 1976 US Standard atmosphere has a total water vapor content of 1.42 (g cm-2). Opening the elevation information setup dialog box In ATCOR3 a digital elevation model (DEM) is used to calculate the effect of radiance and transmittance over rugged terrain. The Slope and Aspect calculations are mandatory for ATCOR3. The Sky View and Shadow calculations are optional. These calculations can be automatically calculated from the DEM or you can import them in the Elevation Information Setup dialog box if you have already created a file containing these values. If you click Calculate for Slope, Aspect, Sky View, or Shadow, PCIDSK files are automatically created in the user folder where you installed Geomatica when you perform the atmospheric correction. By default each file name is the original input file name prefixed with 'slope_', 'aspect_', 'skyview_', or 'shadow_'. The Slope algorithm measures the angle of the incline for each pixel, which is expressed as a value between 0 and 90 degrees. The value is calculated from the plane formed by the vector connecting the left and right neighbours of the pixel and the vector connecting the upper and lower neighbours of the pixel. The Aspect algorithm measures the orientation of the slope of each pixel, which is expressed as a value between 0 and 360 degrees relative to the top of the image. The value is calculated from the orientation of the plane formed by the vector connecting the left and right neighbours of a pixel and the vector connecting the upper and lower neighbours of the pixel. The angle is measured between north (top of image) and the projection of the normal vector of this plane onto the horizontal plane. The Sky View algorithm uses a ray tracing program to determine the proportion of the sky hemisphere visible for each pixel of the terrain. 288

291 The Shadow algorithm uses a ray tracing program and the solar zenith and azimuth angles to calculate the cast shadows. 1. Open the Atmospheric Correction Configuration dialog box, see Opening the Atmospheric Correction Configuration dialog box on page Under Elevation Information Setup, click the Setup button. Calculating slope, aspect, sky view, and shadow 1. In the File list under Elevation, click the file that contains the DEM or click Browse to select a file. In the Layer list select the layer containing the elevation values. 2. In a DEM each change in gray level represents a change in elevation value. In the Elevation step box, type the value that represents the change of one level of gray. 3. Under Slope, either: Click Calculate to calculate the slope values automatically. Click From file to import the slope values from a file. In the From file list, click the file that contains the slope values or click Browse to select the file. In the Layer list, click the layer of slope values. 4. Under Aspect, either: Click Calculate to calculate the aspect values automatically. Click From file to import the aspect values from a file. In the From file list, click the file that contains the aspect values or click Browse to select the file. In the Layer list, click the layer of aspect values. 5. Under Sky View, either: Click None if you do not want to include sky view factor in the atmospheric correction. Click Calculate to calculate the sky view factor automatically. Click From file to import the sky view factor from a file. In the From file list, click the file that contains the sky view factor or click Browse to select the file. In the Layer list, click the layer with the sky view factor. 6. Under Shadow, either: Click None if you do not want to include shadow data in the atmospheric correction. Click Calculate to calculate the shadow data automatically. Click From file to import the shadow data from a file. In the From file list, click the file that contains the shadow data or click Browse to select the file. In the Layer list, click the layer of shadow data. 7. Click OK. Opening the band setup dialog box When you prepared the PCIDSK (.pix) file for atmospheric correction, the band numbers may not match the channel numbers. For example, band 1 from the sensor may not necessarily be in channel 1 in your file. You may need to match the sensor band numbers to the correct image channel numbers. 1. Open the Atmospheric Correction Configuration 289

292 dialog box, see Opening the Atmospheric Correction Configuration dialog box on page Under Sensor Information, click the Band Setup button. Matching band numbers to channel numbers 1. For each row under the Input Channel column, type the channel number that contains the sensor band corresponding to the band number under the Sensor Band# column. 2. In the Output Corrected column, click to select the rows corresponding to the channels that you want to correct. Rows identified by a check mark will be corrected. 3. If the NoData value is included in the metadata, it will be entered automatically. If it is not, in the NoData Value column type the NoData value for each channel in its corresponding row. 4. In the Gain Setting column, type the gain setting value from the header file. The gain setting is only needed for the MOMS and Aster sensors. It represents the offset between the image and the calibration. 5. Click OK. using a CD read algorithm, the values can be extracted from the metadata. 1. Open the Atmospheric Correction Configuration dialog box, see Opening the Atmospheric Correction Configuration dialog box on page Under Correction Parameter, click the Calculate button. About Solar Zenith and Azimuth The Solar Azimuth and Solar Zenith express the position of the sun. The Solar Azimuth is the angle of the direction of the sun measured clockwise from the North along the horizon. If the solar azimuth is measured from the South, usually referred to as the bearing, it will have to be adjusted since Focus assumes that North is the origin. The Solar Zenith is the angle measured between the local zenith and the line of sight of the sun. Illustrating Solar Zenith and Solar Azimuth Opening the Solar Calculations dialog box The solar zenith and azimuth are important values used in the atmospheric correction. If you imported you images Calculating the solar zenith and azimuth 290

293 1. In the Date boxes click the month, day, and year when the image was taken. 2. In the Time boxes, type hours, minutes, and seconds when the image was taken. 3. In the Latitude box, type the y-coordinate of the center of the image. 4. In the Longitude box, type the x-coordinate of the center of the image. 5. Click Calculate. 6. Click OK. About visibility Visibility, or optical depth, is a meteorological statistic that calculates the opacity of the atmosphere at a certain time and place. It measures the furthest distance that a person can see a prominent object. In Focus the range is between 5 and 180 kilometers. Focus uses the value set in the Visibility box. For more information, see Opening the Atmospheric Correction Configuration dialog box on page 285 for the Spatially Varying Conditions, and for Constant Conditions options, see Opening the Run Atmospheric Correction dialog box on page 294. When you use the Spatially Varying Conditions option, Focus calculates the visibility for each pixel in the image using the Visibility value as a starting point for the calculation. When you use the Constant Conditions option, Focus uses the Visibility value as a constant for each pixel in the image. The calculation results in a Visibility layer that is a temporary PCIDSK (.pix) file with its default file name being the the original file name prefixed with 'hot_level_'. Visibility is used to more accurately specify the atmospheric conditions at the time the image was taken. If the metadata that came with the image does not include the visibility values, you can obtain it from the following sources: USA: About adjacency Adjacency is the effect of backscattering on neighboring pixels. It is used to more accurately specify the atmospheric conditions at the time the image was taken. The adjacency effect is calculated for an area around each pixel up to a maximum of 200 pixels. For example, an image with 30-meter resolution like Landsat will have a maximum Adjacency value of 6, because 200 multiplied by 30 meters is 6000 meters, which is 6 kilometers. Therefore, an Adjacency value of 0 would not take the adjacency effect into consideration while 6 would calculate the maximum effect. The default is 1 and is suitable for most cases. Determining the offset to surface temperature value Occasionally there may be a consistent difference in temperature between actual temperatures measured on the ground and those reported in the Spectral Plot. To verify if you need to compensate for this difference, you need to collect the temperature of identifiable points in 291

294 the region at the time the image was captured. These temperature samples are sometimes referred to as 'ground truths'. If you compare the ground truths to the results from the same points collected on a temperature layer using the Spectral Plot, the temperature for each point in both should be the same. If you observe a consistent difference in temperature, you can enter the value in the Offset to surface temperature box. For example, you compare the actual water temperatures of three lakes to their temperatures reported in the Spectral Plot and discover that there is a difference of 2 degrees between the ground truths and the Spectral Plot. Therefore, you type 2 in the Offset to surface temperature box. 1. Configure and run the atmospheric correction. For more information, see Opening the Atmospheric Correction Configuration dialog box on page 285 and Opening the Run Atmospheric Correction dialog box on page Position the cursor precisely on the feature that you can clearly identify in the image for which you have a known ground temperature. 3. In the Maps tree, right-click the ATCOR MetaLayer. 4. Click Spectra Plot. 5. On the Atcor Spectra Plotting dialog box, click From Image. 6. Compare the actual temperature of the feature to the temperature displayed under Report. 7. Repeat step 2 to step 6 for each ground truth. Editing an existing calibration file to create a new file The standard calibration files are in the cal folder under the atcor folder where you installed Geomatica (for example, C:\Program Files\Geomatica_V100\atcor\cal). Each sensor has a set of calibration files created by Dr. Richter. When you complete the Atmospheric Correction Configuration dialog box, you can use one of the standard calibration files since they are sufficient in most cases. If you are not obtaining expected results, compare the calibration coefficients (gain and bias values) in your data#s metadata file to those in the calibration file. If the values are significantly different, you can create you own calibration file specific to your data. The calibration file contains a table of the bands, the gain value for each band, and the bias for each band. ATCOR uses mw/cm-2 sr-1 micron-1 as the radiance unit for each band, except the thermal band which uses mw m-2 sr-1 micron-1. Since the sensors may use a different radiance unit, you may need to convert the values. For more information, visit For example, some calibration coefficients are measured in W m-2 sr-1 micron-1. To convert it to the ATCOR radiance value, you multiply the values in the metadata file by 0.1. Example of a calibration file 292

295 comparing the water reflectance values in the NIR band to the reflectance values in the snow band (1.6 um band). In most cases the default values for reflectance thresholds will identify water and snow in image. However, you may have to iteratively adjust the threshold values and recreate the mask to achieve the desired results. 1. In the Maps tree, right-click the ATCOR MetaLayer. 2. Click Define Haze and Cloud. Automatically creating a mask. 1. Open a standard calibration file for the sensor appropriate for your data. 2. Open the metadata file that came with your data. 3. If required, convert the values from the metadata file to ATCOR radiance units: mw/cm-2 sr-1 micron-1 (or mw m-2 sr-1 micron-1 for thermal bands). 4. Replace the bias and gain values for each band with the converted values from the metadata file. 5. Save as a new file with the.cal extension in the cal folder in the folder for the appropriate sensor. Opening the Define Haze and Cloud dialog box After configuring the parameters for atmospheric correction, you must create a mask over the hazy and cloudy areas in the image while excluding areas covered by water or snow. Water and snow are identified by 1. Click Automatically Calculate Haze and Cloud. 2. Under Mask Size, click either: Large area haze mask to create a mask over all the areas that may contain haze. This option also includes areas where haze is suspected, but may not be obvious upon visual inspection. Smaller area haze mask to create a mask only over the areas where the haze is obvious. 3. Under Haze Thickness, click either: Correct thin haze to thick haze if you want to include the thick haze (cloud cover) when you perform the correction. Correct thin to medium haze if you want to ignore the thick haze (cloud cover) when you perform the correction. 4. In the Water Refl. Threshold in NIR (%) box, type the value in percent representing the limit below which is considered water reflectance values in the NIR sensor band. 293

296 5. In the Water Refl. Threshold in Snow (1.6um) (%) box, type the value in percent representing the limit below which is considered water reflectance values in the 1.6 um sensor band. 6. In the Cloud Refl. Threshold in Blue (<0.8um) (%) box, type the value in percent representing the limit below which is considered cloud reflectance values. 7. Under Output, click either: Display to show the mask in the Focus view pane. Save to save the mask layer in a file. In the File list, click the file where you want to save the mask or click Browse to select the file. In the Haze Layer list, click the layer where you want to save the haze mask. In the Cloud Layer list, click the layer where you want to save the cloud mask. 8. Click Create Mask. Importing the masks from a file 1. Click Load Haze and/or Cloud from File. 2. Under Haze, in the File list click the file that contains the haze mask or click Browse to select the file. In the Layer list, click the layer containing the haze mask. 3. Under Cloud, in the File list click the file that contains the cloud mask or click Browse to select the file. In the Layer list, click the layer containing the cloud mask. 4. Click Create Mask. Editing the Cloud mask 1. Right-click the ATCOR MetaLayer. 2. Click Edit Cloud Mask. 3. Use the New Shapes tools to modify the bitmap. For more information, see Adding points to an active layer on page 303. Editing the Haze mask 1. Right-click the ATCOR MetaLayer. 2. Click Edit Haze Mask. 3. Use the New Shapes tools to modify the bitmap. For more information, see Adding points to an active layer on page 303. Editing the Visibility layer 1. Right-click the ATCOR MetaLayer. 2. Click Edit Visibility. 3. Use the New Shapes tools to modify the bitmap. For more information, see Adding points to an active layer on page 303. Opening the Run Atmospheric Correction dialog box When you perform the atmospheric correction, Focus adds a thematic raster metalayer to the Maps tree. The metalayer contains the image being corrected, the Haze bitmap mask layer, the Cloud bitmap mask layer, the visibility layer, and a layer with the Value-Added Data. 294

297 To use the Spatially Varying Conditions option, you must have the Red, near-infrared (NIR), and Short Wavelength Infrared (SWIR) bands, and you must have reference areas of known reflectance such as a section of dense vegetation or a body of water present outside the haze to use as a reference target. When you use the Spatially Varying Conditions option, Focus calculates the visibility for each pixel in the image using the value set in the Visibility box on the Atmospheric Correction Configuration dialog box as a starting point for the calculation. Use the Constant Conditions option when you are missing one of the bands, the image does not contain a reference target, or you are sure that the image represents an area with constant atmospheric conditions such as an area without rugged terrain, large bodies of water, or mountains. When you use the Constant Conditions option, Focus uses the value set in the Visibility box on the Atmospheric Correction Configuration dialog box as the visibility for each pixel in the image. The result of the atmospheric correction is a scaled surface reflectance image with a range of 0 to 255 for 8-bit data and 0 to for 16-bit data. If you want unscaled values or percent reflectance values, divide the scaled values by 4 for 8-bit data and by 10 for 16-bit data. For example, 150 divided by 10 equals 15% reflectance for a 16-bit image. 1. In the Maps tree, right-click the ATCOR MetaLayer. 2. Click Run Atmospheric Correction. Running the correction 1. Click Constant Conditions if you want to perform the correction assuming relatively uniform atmospheric conditions over the image. 2. Click Spatially Varying Conditions if you want to perform the correction assuming differing atmospheric conditions throughout the image. 3. Under Corrected Output, in the File box click the file where you want to save the corrected data or click Browse to select a file. Deriving additional data from the corrected imagery 1. Under Value-added Data Output, in the File box click the file where you want to save the additional data or click Browse to select a file. 2. To perform a transformation that minimizes the influence of soil brightness, select the Soil Adjusted Vegetation Index check box. 3. To calculate the green leaf density, select the Leaf Area Index check box. If you want to change the equation used for the LAI calculation, click LAI Options. For more information, see Opening the Leaf Area Index Model dialog box on page To calculate the calculate the amount of photosynthetically active radiation absorbed by a plant canopy, select the Fraction of Absorbed Radiation check box. If you want to change the values used in the FPAR calculation, click FPAR Options. For more information, see Changing the values for the 295

298 fraction of photosynthetically active radiation (FPAR) equation on page To calculate ground reflectance, select the Surface Albedo check box. 6. To calculate the difference between the emitted atmospheric radiation and the emitted surface radiation, select the Thermal Flux Difference check box. 7. To calculate the exchange rate of energy between the earth#s surface and the underground, select the Ground Heat Flux check box. 8. To calculate the shortwave solar radiation absorbed by the surface, select the Absorbed Solar Radiation check box. 9. To calculate the exchange rate of stored heat energy between the air and the earth#s surface, select the Latent Heat check box. Latent heat flux is measures the amount of energy needed to change matter from one state to another (from solid to liquid to gas). 10. To calculate the exchange rate of excess heat energy between the air and the earth#s surface, select the Sensible Heat check box. Sensible heat flux measures the amount of energy needed to change air temperature. 11. To calculate the difference between absorbed and emitted shortwave and longwave radiations, select the Net Radiation check box. 12. Click Run Correction. Opening the Leaf Area Index Model dialog box The leaf area index (LAI) is the density of the green leaves in an area. It is a measure of the green leaf area (one-side) per unit of surface area. You can choose one of two equations to calculate the density: the Soil Adjusted Vegetation Index or the Normalized Difference Vegetation Index. Both equations contain three parameters whose values depend on the type of vegetation being measured and on the season in which they are being measured. The LAI can only approximate typical trends in the vegetation. It should not be used to replace or confirm field measurements of other types of vegetation in different seasons. The defaults provided for the equations are typical for soybean crops (Choudury et al. 1994). By using a constant set of values, either custom or default, to calculate the LAI for images of the same area over time, you can uncover trends in the vegetation. SAVI uses the red and near-infrared bands to measure the density and vigor of green vegetation by attempting to eliminate the reflectivity of the ground beneath the canopy. NDVI uses the visible and near-infrared bands to measure the density and vigor of green vegetation by comparing the amount of visible light reflected to the amount of near-infrared light reflected. 1. Open the Run Atmospheric Correction dialog box, see Opening the Run Atmospheric Correction dialog box on page Under Value-Added Data Output, select the Leaf 296

299 Area Index check box. 3. Click the LAI Options button. Selecting the equation for calculating the Leaf Area Index 1. Select one of the following: SAVI for the Soil Adjusted Vegetation Index equation. NDVI for the Normalized Difference Vegetation Index equation. Changing the values for the fraction of photosynthetically active radiation (FPAR) equation The Fraction of Photosynthetically Active Radiation (FPAR) equation uses the red and near-infrared bands to calculate the fraction of radiation between 400 and 700 nm absorbed by green vegetation. The FPAR equation contains three parameters whose values depend on the type of vegetation being measured and on the season in which they are being measured. The equation also includes the result from the leaf area index (LAI) equation that you selected (see Opening the Leaf Area Index Model dialog box on page 296 ). The FPAR equation can only approximate typical trends in the vegetation. It should not be used to replace or confirm field measurements of other types of vegetation in different seasons. The defaults provided for the equations are typical values based on several studies (Asrar et al. 1984, Asrar 1989, Wiegand et al, 1990, 1991). By using a constant set of values, either custom or default, to calculate the FPAR for images of the same area over time, you can uncover trends in the vegetation. 1. Open the Run Atmospheric Correction dialog box, see Opening the Run Atmospheric Correction dialog box on page Under Value-Added Data Output, select the Fraction of Absorbed Radiation check box. 3. Click the FPAR Options button. Opening the Advanced Option dialog box The Advanced Options are parameters used in producing the data in the Value-Added Data Output section on the Run Atmospheric Correction dialog box. The availability of the parameters depends on the presence or absence of data: The Visibility data, BRDF Correction, and Terrain Reflectance sections are only available in ATCOR3. The Emissivity and Radiation and heat flux sections are only available if your data includes a thermal band. The Reference pixels section is only available if your data does not include a Short Wavelength Infrared (SWIR) band. If your data does include one, Focus automatically calculates the reference pixels. 1. In the Maps tree, right-click the ATCOR MetaLayer. 297

300 2. Click Advanced Options. Setting the parameters 1. Under Visibility data, click Calculate to calculate the visibility values when you perform the atmospheric correction or click Use Existing to select a visibility layer calculated previously. If you selected Use Existing, in the File list click the file that contains the visibility layer or click Browse to select a file. In the Layer list, click the layer containing visibility values. 2. (Available only if your data includes a thermal band) Under Emissivity, click Constant to use 0.98 as the emissivity constant for all the pixels in the image or click Surface cover dependant to calculate the emissivity for each pixel using specific values depending on whether the pixel represents water, vegetation, or another material. 3. (Available for ATCOR2 only and only if your data includes a thermal band) In the Scene air temperature box, type the overall temperature present in the area at the time the image was taken. Select the temperature scale used to measure the air temperature. 4. (Available for ATCOR3 only and only if your data includes a thermal band) In the Air temperature box, type the temperature of the air at a specified elevation. Select the temperature scale used to measure the air temperature. In the Elevation box, type the elevation at which the air temperature was measured. 5. (Available for ATCOR3 only and only if your data includes a thermal band) In the Temperature gradient box, type a value representing the number of degrees Celsius at which the temperature will change per 100 meters of elevation. 6. (Available for ATCOR3 only and only if your data includes a thermal band) In the Water vapor partial pressure box, type a value representing the rate at which the pressure will change per 100 meters of elevation. 7. In Threshold T1 box, type the value representing the limit below which is considered bare soil or other nongreen materials. For more information, see Setting the thresholds for the reference pixels on page In Threshold T2 box, type the value representing the limit below which is considered high NIR reflectance. For more information, see Setting the thresholds for the reference pixels on page In the Reflectance % in RED band box, type the value in percent representing the limit below which is considered vegetation. For more information, see Setting the thresholds for the reference pixels on page (Available for ATCOR3 only) Under BRDF Correction, click Empirical Correction if you want to correct view and illumination angle effects or click No Correction if you do not. To specify which empirical correction function you want to use, click BRDF Options. For more information about the Bidirectional Reflectance Distribution Function (BRDF), see Opening the Empirical BRDF Correction dialog box on page (Available for ATCOR3 only) Under Terrain Reflectance, you select the method that you want 298

301 to use to calculate the terrain reflectance for each pixel, which is used to calculate the adjacency correction and the spherical albedo effect. You can click either: 3 iterations to calculate the average terrain reflectance. The equation is computed iteratively with the terrain view factor and sky view factor calculated from the digital elevation model (DEM) to achieve convergence. No iterations to calculate the terrain reflectance without iterative calculations to improve the accuracy. 12. Click OK. Setting the thresholds for the reference pixels If the data contains a Short Wavelength Infrared (SWIR) 1.6 m or 2.2 m band, Focus automatically calculates the reference pixels when you run the atmospheric correction using the Spatially Varying Conditions option. Reference pixels are target areas of known reflectance in one band present outside the haze. In Focus the target areas are areas of dense, dark vegetation. The reference pixels are used to develop a spatial map of the visibility (optical depth) of the pixels in the image. Threshold T1 identifies areas with dense vegetation by calculating the Ratio Vegetation Index using both the red and near-infrared sensor (NIR) bands. The threshold marks the value representing the limit below which is considered bare soil or other nongreen materials. Threshold T2 identifies pixels with low reflectance in the NIR band. The threshold marks the value representing the limit below which is considered materials with high reflectance. It is used to exclude vegetation with high reflectance, therefore identifying dark vegetation. Reflectance % in RED band identifies the value in percent representing the limit below which is considered vegetation. The reflectance values for dark vegetation are typically between 1 to 3% in the RED band. Dr. Richter recommends that you begin with a value of 2% and compare the result to the original image to determine if the identified targets are acceptable reference pixels. See Opening the Advanced Option dialog box on page 297. Opening the Empirical BRDF Correction dialog box Bidirectional Reflectance Distribution Function (BRDF), available only in ATCOR3, corrects the reflectance effects resulting from the view angle and illumination angle when the image is taken. The reflectance can appear very different depending on the position of the sensor and the position of the light source. The texture and composition of the surface also affect reflectance. BRDF compensates for these effects by computing a factor (G) used to reduce the reflectance of pixels with 299

302 extreme incident angles so that they more closely resemble the reflectance values of pixels with moderate incident angles. In the BRDF equation: t represents the threshold angle i represents the incidence angle e represents the exitance angle (for sensors with the tilt capability) The lower boundary value (g) is a value less than 1 that constrains the factor G to prevent over-reducing the reflectance of pixels with extreme incident angles:. By default the lower boundary value is in a larger off-nadir viewing angle, 20 to 30 degrees for example. (4) G = sqrt[cos(i)*cos(e)/cos(t)] the sensor was tilted when the image was taken resulting in a larger off-nadir viewing angle, 20 to 30 degrees for example. 2. In the Threshold angle box, type the value that results from adding 20 degrees to the solar zenith value. 3. In the Lower boundry box, type a value to raise or lower the boundary. 4. Click OK If the corrected reflectance values appear too low (dark), decrease the lower boundary value and repeat the correction. 1. Open the Advanced Options dialog box, see Opening the Advanced Option dialog box on page Under BRDF Correction, click Empirical Correction. 3. Click the BRDF Options button. Selecting the BRDF equation 1. Select one of the following. Click: (1) G = cos(i)/cos(t) when the incidence angle is between 60 to 90 degrees. This equation is recommended for most cases. (2) G = sqrt[cos(i)/cos(t)] when the incidence angle is between 60 to 90 degrees. (3) G = cos(i)*cos(e)/cos(t) when the sensor was tilted when the image was taken resulting 300

303 Chapter 8 Understanding vector layer types Vectors are a way of presenting spatial information. Instead of representing that information in pixels, vectors represent the information as points, lines, and polygons. Focus provides two main methods for presenting the vectors: Unstructured and Topological. Each method contains several vector layer types. Vector layers contain a number of default attributes that can be viewed with the Attribute Manager. For more information, see Understanding vector layer type default fields on page 307. Unstructured vector layers An unstructured layer can contain a combination of shapes. You can limit the layer to a particular type. The following describes the shapes available on an unstructured layer. Point: A shape that contains only one vertex. Line: A shape that contains two or more vertices, where the first and last vertices do not conjoin. Whole Polygon: A shape that contains three or more vertices, where the first and last vertices conjoin. Unconnected Table: A layer that contains attributes but is not associated to a geographical component. (See Creating an unconnected table on page 306 ) About topological layers Topology is a mathematical representation of the surface features of a location. Topology involves not only building a relationship between the shape and the attributes, but also a relationship between the shapes themselves. Topological Line: Contains lines that use topological conventions. A topological line can contain several vertices, but only two nodes. A node is the start point or the end point of a line. A topological line layer is composed of two layers. One layer stores the lines and the other stores the nodes. Focus generates and manipulates nodes in the node layer as you edit and create the topological lines. Understanding topological lines 301

304 Topological Polygon Contains polygons that use topological conventions. A topological polygon is a closed figure formed by one or more topological lines that define the boundary of a specific location. When a topological polygon overlaps another, the intersecting points become nodes; the lines are split, resulting in a new polygon in the overlap. That is, two topological polygons become three. A topological polygon layer is composed of three layers. When you create a topological polygon layer, Focus also generates a line layer and a node layer. As you create and edit polygons, Focus manipulates the lines and nodes that form the polygon. The line layer includes attributes that identify which polygons lie on either side of each line. The region outside the boundary of the digitized areas on the layer are represented by a global polygon. This global polygon, called Outside Area, appears as -1 in the Attribute Table for topological line layers. These attributes describe the relationship between the shapes. Understanding topological polygons Thematic rasters A thematic raster is a raster with associated attributes. Normally, rasters present spatial information as pixel values. The numeric value of the pixel represents the attribute for that pixel. Neighboring pixels with the same pixel value collectively represent a surface feature. In thematic rasters, the pixel values are associated to any number of attributes, which can be viewed using the Attribute Manager. In Focus, the attributes for a thematic raster are stored in a vector segment in its file. Understanding vector editing in a math model area A Math Model Area is similar to an Area, except the projection is determined by a math model segment contained in the image file. The image is displayed 302

305 without correction in the viewer, but accurate ground coordinates are calculated for each pixel using the pixel and line coordinates, the math model, and the digital elevation model (DEM) or an approximate elevation value that you provide. For more information, see Using a math model with images on page 40. In the Math Model Area, you can digitize geocoded three-dimensional vectors on a raw image, instead of going through the potentially time-consuming, labor-intensive process of orthorectifying the imagery. Vectors are saved in the projection of the layer without the effects of the math model. As such, the vectors have accurate X, Y, and Z coordinates. You can open vectors digitized in the Math Model Area in an Area containing an orthorectified or geometrically corrected image and the vectors will display correctly. However, if you open vectors without elevation in a Math Model Area, the vectors may be offset from the correct position, as it uses elevation values to calculate the correct position. When you edit vectors in a Math Model Area, you are essentially moving objects in three-dimensional space using two-dimensional vision. You cannot modify the X and Y coordinates of the vector without affecting the Z coordinate. To edit only the X and Y vector coordinates, open the vectors in a planimetric layer instead. Adding a new vector layer 1. In the Maps tree, right-click an Area and click New Vector Layer. 2. In the New Vector Layer dialog box, enable the type of layer that you want in the Layer Type area. For more information about layer types, see Understanding vector layer types on page In the Georeferencing area, enable one of the following options: Use Area Georeferencing: uses the same georeferencing as defined in the New Area. Use Layer Georeferencing: uses the same georeferencing as defined in an existing layer. Choose a layer that has the desired georeferencing form the list box. User-entered: defines the georeferencing. Enter the projection, bounds, and extents as required. 4. Click OK. Adding points to an active layer 1. On the Editing toolbar, click the New Shapes arrow and choose Points. 2. Click in the view pane where you want to add a point. 3. Repeat step 2 for all points that you want digitized. Adding a line or a polygon to an active layer 1. On the Editing toolbar, click the New Shapes arrow and choose Line or Polygon. 303

306 2. Click in the view pane where you want to add the first point of the line or polygon. 3. Repeat step 2 until you have digitized the shape that you want. 4. Double-click the last vertex to complete the shape. Adding a rectangle or ellipse to an active layer 1. On the Editing toolbar, click the New Shapes arrow and choose Rectangle or Ellipse. 2. Click in the view pane where you want to add a rectangle or ellipse. For a rectangle, start at a corner of the area where you want to draw a rectangle; for an ellipse, start in the center of the area. 3. Drag to form a shape. If you want to create a square or a circle, press and hold the Shift key while dragging. Tracing a line on an active layer 1. On the Editing toolbar, click the New Shapes arrow and choose Trace. 2. Click in the view pane where you want to start tracing. 3. Trace over the line. 4. Double-click to complete the trace. Digitizing 3-D vectors Using the mono-restitution process, you can digitize vectors with accurate X, Y, and Z coordinates with the New Shapes tools. To set up mono-restitution, you need a raw image with a math model segment and a digital elevation model (DEM), or an estimate of the elevation. The math model and DEM are used to set the georeferencing for the Math Model Area, in which the image is displayed without correction in the viewer. Accurate ground coordinates are calculated for each pixel using the pixel and line coordinates, the math model, and the DEM or approximate elevation value. For more information, see Using a math model with images on page 40 and Understanding vector editing in a math model area on page In the Focus window, open a raw image with a math model segment. Click Math Model. 2. Set up the Math Model Area (see Using the math model for georeferencing on page 41 ). 3. Use the New Shapes tools on the Editing toolbar to digitize vectors (see Adding points to an active layer on page 303 ). Performing tasks in the Attribute Manager The Attribute Manager is another way of visualizing data. Each record in the Attribute Manager represents a shape on the layer. Each shape is described by a number of attributes. You can view the records individually or in a table. In the table, each row records all attributes for a shape. Each column holds values for an attribute. 304

307 See: Viewing records on page 307 Selecting and clearing records and fields on page 307 Understanding vector layer type default fields on page 307 Adding records to the Attribute Manager on page 309 Adding new fields on page 309 Setting the field definitions on page 309 Changing an existing field to a geometry field on page 310 Updating the geometry on page 311 Using find and replace in the Attribute Manager on page 311 Selecting all records that match a value in the current cell on page 312 Using the compute function on page 314 Creating a relational database on page 312 Opening the Aggregate Attributes dialog box on page 315 Opening the Area Neighbors dialog box on page 315 Opening the Z-value Transfer dialog box on page 317 Exporting layer attributes to a file on page 318 About the Preferences dialog box The Preferences dialog box contains options that control the cursor#s behavior in the Attribute Manager and controls what statistics are displayed in the Attribute Manager. Select the topic that interests you: Controlling the Attribute Manager cursor on page 305 Setting a selected record statistics display on page 306 Controlling the Attribute Manager cursor You can control the cursor movement and behavior in the Attribute Manager through the Attribute Manager Preferences dialog box. 1. In the Attribute Manager, click Edit and then click Preferences. 2. In the Preferences dialog box, choose one of the following options from the After pressing #Enter# list box: Moves To Next Record: moves the cursor from record to record as you press Enter Moves To Next Field: moves the cursor from field to field as you press Enter Does Not Move: keeps the cursor in a cell when you press Enter 305

308 3. Choose one of the following options from the When entering cell list box: Select Entire Cell: highlights the contents of the cell Go To Start Of Cell: places the cursor before the contents in a cell Go To End Of Cell: places the cursor after the contents in a cell 4. Click OK. Setting a selected record statistics display When you select a record, its statistics are displayed in the Attribute Manager. You can choose the statistics you want to display. 1. In the Attribute Manager, click Edit and then click Preferences. 2. In the Preferences dialog box, enable any of the following check boxes in the Field Statistics area: Count: displays the number of selected records Sum: calculates the sum of the values for the selected records for each numeric field Mode: calculates the value that occurs the most frequently among the selected records for each field Mean: calculates the average value of the selected records for each numeric field. The average is obtained by adding values of the selected records and dividing that value by the number of records used in the sum. Minimum: displays the lowest value in the numeric field from the selected records Median: ranks for each numeric field the values of the selected records in numerical order. The median is the middle value of the selected records. Maximum: displays the highest value in the field from the selected records Standard Deviation: measures the variation in the distribution of values, which is calculated from square root of the variance 3. Click OK. Creating an unconnected table An unconnected table is a layer that contains attributes that are not directly associated to a vector representing a geographical location. 1. Create an unstructured layer. For more information, see Adding a new vector layer on page Right-click the layer and click Attribute Manager. 3. Design the table as you require. (See Adding new fields on page 309 ) 4. From the Record menu, click Add New. 5. Enter data. Restricting the layer so you cannot add shapes to it 1. In the Focus window, save the layer. 2. Click the Files tab. 3. Right-click the layer and click Properties. 4. In the File Properties dialog box, click the 306

309 MetaData tab. 5. Click the Add button. 6. In the Value column next to LAYER_TYPE, type TABLE in upper case letters. 7. Click OK. Viewing records When you view individual records, the fields appear in the first column followed by the values for that record. When you view all records in a table, each row is a record that contains all the attributes for the shape. Each column is a field that contains the values for each attribute. To view an individual record From the View menu in the Attribute Manager, click Record Display. To view a record in a table From the View menu in the Attribute Manager, click Table Display. Opening a file saved as an attribute If a file name and a path are saved as an attribute, you can open the file from the Attribute Manager. 1. In the Attribute Manager, click the cell containing the file name and path of the file that you want to open. 2. From the View menu in the Attribute Manager, click File. The file will open using the operating system's default application for that file type. Selecting and clearing records and fields To select a record, click the lead cell next to it. You can press and hold Shift and click a range of records or fields, or press and hold Ctrl and click multiple records or fields. Statistics for selected records display at the bottom of the Attribute Manager. The lead cell in the current record is highlighted in yellow. To select a field, click the heading of the field. The heading in the current field is highlighted in yellow. On the Attribute Manager toolbar, click the Clear selected records or Clear selected fields button. Understanding vector layer type default fields When you create a new vector layer, it automatically contains a set of default fields that Focus maintains. You can modify definitions of some default fields; however, most are restricted by the system. (See Setting the field definitions on page 309 ) The following table lists the fields maintained by Focus. 307

310 Table 20. Default Fields Field Name Description Layer Type REPCode Angle TextString GroupID Contains the key to define the appearance of the shapes according to the Representation Editor. (See Using the GPS tool on page 351 ) Controls the slant of the text string or point. Measured in radians by default, but you can change it to display in degrees, gradians, or mils. Defines the field to accept characters, such as text. You can type directly on the layer or in the TextString field. Identifies a set of shapes that you grouped together. (See Unstructured Point Unstructured Point Unstructured Point Line Unstructured Whole Polygon Area Field Name Description Layer Type Perimeter ArcIdList RightAreaId Grouping shapes on page 321 ) The identification number is generated by Focus and cannot be changed. Displays the computed area enclosed by the polygon. Displays the computed circumference of the polygon. Identifies the lines that compose a polygon in a topological layer. (See About topological layers on page 301 ) Identifies the polygon on a topological layer which is on the right of the line. (See About topological layers on page 301 ) Whole Polygon Topological Polygon Whole Polygon Topological Polygon Topological Polygon Topological Line 308

311 Field Name Description Layer Type LeftAreaId StartNodeId EndNodeId Length Identifies the polygon on a topological layer which is on the left of the line. (See About topological layers on page 301 ) Identifies the point (node) that begins a topological line. (See About topological layers on page 301 ) Identifies the point (node) that ends a topological line. (See About topological layers on page 301 ) Displays the computed distance covered by the line. Topological Line Topological Line Topological Line Line Topological Line From the Field menu in the Attribute Manager, click Show All. Adding records to the Attribute Manager As you add shapes in the view pane, a record is automatically created in the Attribute Manager. Each record contains the default fields or the fields that were set when the table was created. You can add a record to the table not associated with a shape. (See Creating an unconnected table on page 306 ) 1. From the Maps tree, right-click a layer and click Attribute Manager. 2. From the Record menu in the Attribute Manager, click Add New. Adding new fields Records in the Attribute Manager contain default fields and fields that were set when the table was created. You can add new fields or modify the existing ones. To modify the fields, see Setting the field definitions on page 309 You can also add new fields directly from the Table Definitions dialog box. 1. From the Maps tree, right-click a layer and click Attribute Manager. 2. From the Field menu in the Attribute Manager, click Add New. For information on how to modify the fields, see Setting the field definitions on page 309. Setting the field definitions 309

312 You can define the contents of the Attribute Manager table by choosing attributes in the table and by adding or removing records using the Table Definition dialog box. You can also set the field properties for new and existing records. 1. From the Edit menu in the Attribute Manager, click Table Definition. 2. In the Table Definition dialog box, do any of the following: To hide a field, disable the appropriate check box in the Shown column. To change a field name, double-click the field in the Name column and type a new name. To add a field, click the Add button. To remove a field, select it and click the Remove button. 3. Type or choose data that will appear by default from the Default Value list box. 4. Type a value that will appear in fields that do not contain real data from the NoData Value list box. NoData values are not included in computations. 5. Choose one of the following options from the Read only list box: No: lets you change values in a field Yes: restricts changes to a field 6. Choose how you want to align data in a field from the Justification list box. 7. Type or choose the width of a field in characters in the Field size list box. 8. Type or choose a number of decimal places displayed in a field in the Decimal places list box. 9. Choose one of the following options from the Scientific notation list box: Yes: displays values in a field as scientific notations No: displays values in a field as regular numbers Auto: displays values as either regular numbers or scientific notations, depending on which is shorter 10. Choose one of the following unit types for a field from the Angular units list box: Radians: expresses angles in radians, where 2 pi radians equals the 360 degrees in a circle (one radian equals approximately degrees) Degrees: expresses angles in degrees, which is the angle between two adjacent radii measured at the center of the circle tht is divided along its radius into 360 equal parts Mils: expresses angles in mils, which measure angles where 1 mil equals 1/6,400 of a circle (1 mil equals approximately degrees) Grads: expresses angles in grads, which measure angles where 400 grads equals the 360 degrees in a circle (a 90-degree right angle equals 100 grads) 11. Choose a conversion type from the Conversion list box. If you choose New, type a factor in the Conversion Factor box. 12. Click OK. Changing an existing field to a 310

313 geometry field Geometry fields are system fields that display the measurements of lines or polygons on a layer. Focus automatically calculates and updates these measurements as you modify the respective shapes. Three Geometry Field types are available: Length: calculates the length of a line Perimeter: calculates the circumference of a polygon Area: calculates the area of a polygon When you create a new vector layer, Focus automatically creates Length, Area, and/or Perimeter fields in the Attribute Manager according to the selected layer type. You can modify some properties, but most remain unavailable. 1. From the Edit menu in the Attribute Manager, click Table Definition. 2. In the Table Definition dialog box, enable the check box in the System column for the field that you want to change into a Geometry Field. 3. In the Geometry Field Properties area, choose the type of field that you want from the Type list box. 4. Choose a unit of measurement for the field from the Display units list box. 5. Click OK. Adding all appropriate geometry fields 1. From the Edit menu in the Attribute Manager, click Table Definition. 2. In the Geometry Field Properties area, click Create. 3. Select each new field and define as necessary using the available properties. (See Setting the field definitions on page 309 ) Updating the geometry If you edit a layer outside of Focus, the Geometry Fields may no longer be up-to-date when you reopen them in Focus. 1. From the Maps tree, right-click a layer and click Attribute Manager. 2. From the Field menu in the Attribute Manager, click Update Geometry. Using find and replace in the Attribute Manager 1. From the Edit menu of the Attribute Manager, click Find or Replace. 2. In the Find and Replace dialog box, type the characters that you want to find in the Find what box. 3. Enable any of the following check boxes: Match case: searches for the examples with the same capitalization as the characters in the Find what box only Match entire cell: searches for the examples that contain only the characters in the Find 311

314 what box. For example, if you type 123 in the Find what box, you will only receive matches for cells that contain only 123. You will not receive matches for other numbers such as or Limit search to selected fields: searches only in a field selected in the Attribute Manager Limit search to selected records: searches only in a record selected in the Attribute Manager 4. Click Find next. 5. If you want to replace text, click the Replace tab and type the characters that you want to use as the replacement in the Replace with box. 6. Click Replace. If you want to replace all the examples with the replacement characters, click Replace all. Creating a relational database You can join layers to form a relational database. One layer serves as the source of the data. This layer, called the Secondary Table, usually contains an Unconnected Table (See Creating an unconnected table on page 306 ), but you can also use another layer in your project as the source. The layer that receives the attributes from the Secondary Table is called the Primary Table. When you join layers, you select one field in Primary Table and a corresponding field in the Secondary Table to serve as the key. The key is the common link between the layers. The attributes from the Secondary Table appear in the Primary Table. The Secondary Table acts like a look-up table for the attributes. If you change the values in the Secondary Table, the Primary Table is automatically updated with the new values, as long as the tables are joined. 1. Right-click the layer that you want to use as the Primary Table and click Attribute Manager. 2. From the Tools menu in the Attribute Manager, click Table Join. 3. In the Define Table Join dialog box, click Browse. 4. In the Select Layer dialog box, choose the layer that you want to use as the Secondary Table. 5. In the Primary Table#s Attribute box, select an attribute. 6. Select the attribute from the Secondary Table#s Attributes box that you want to join with the attribute from the Primary Table#s Attribute box. 7. Click the Add button. 8. Click OK. Selecting all records that match a value in the current cell A query searches and selects records that correspond to a set of criteria that you define. Match Current Cell: All records that contain the same value as the current cell are selected. The statistics of the selected records display at the bottom of the Attribute Manager. (See Setting a selected record statistics display on page 306 ) 312

315 1. Select a value that you want to match. 2. From the Record menu in the Attribute Manager, click Query by and then click Current. Exclude Current Cell: All records that do not contain the same value as the current cell are selected. The statistics of a selected record is displayed at the bottom of the Attribute Manager. (See Setting a selected record statistics display on page 306 ) Selecting all records that do not match a value in a selected field 1. Select a value that you want to exclude from the search. 2. From the Record menu in the Attribute Manager, click Query by and then click Excluding Current. Query by Example: You can create an expression that selects all corresponding records. An expression can be a statement where two attributes are connected by a relational operator to produce a result. It can also be two or more statements joined by an AND or OR operator. For example, if you have an attribute called Length that describes the length of rivers on a layer, you can query 'Length > 10.# The result shows all records that contain a value greater than 10 in the Length field. Making a query by example 1. From the Record menu in the Attribute Manager, click Query by and then click Example. 2. In Query by Example dialog box, choose New from the Equation list box. 3. In the Attributes list, select the attribute you want to use in the query. 4. Select a relational operator (such as =, >, <, and so on) from the list box next to the Attributes list. 5. Enable one of the following options: Attribute Values: uses field values in the query Attributes: uses another attribute in the query 6. Select a value or attribute from the appropriate list. 7. Enable one of the following options: AND: selects records that are true for both joined statements OR: selects records that are true for at least one of the joined statements 8. Click Add. 9. Repeat step 3 to step 8 as needed. 10. Click Save. 11. Enter a name for the equation in the Equation name box and click OK. 12. In the Query by Example dialog box, click OK. Query by Subset If you select Query by Subset before using the Query by features (Current, Excluding Current, and Example), the 313

316 query is limited to the selected records only instead of performing the query on all the records. Limiting the query to selected records 1. Select records in the Attribute Manager. 2. From the Edit menu in the Attribute Manager, click Query By Subset. 3. Perform a query. Using the compute function Compute creates a field containing the results of an equation or expression involving the attributes in a layer. You can build equations using the calculator or you can create more complex expressions with the Advanced Compute features and EASI scripts. For more information about EASI scripts, see the EASI User Guide. When you build an expression, either type the expression in the Expression box or build the expression by clicking the buttons and items in the dialog box. Combining the two methods may cause unwanted effects. 1. From the Field menu in the Attribute Manager, click Compute. 2. From the View menu in the Compute dialog box, click one of the following options: Basic: creates an equation using the attributes and the calculator Advanced: creates an expression using the attributes, the calculator, and functions 3. Build an expression. You can use any combination of the following to create the expression that you want: Type all or part of the expression in the Expression box. Text should be placed in double quotes (for example, #text#). Double-click an attribute in the Attributes list to add it to the expression. Use the calculator to include integers and the basic mathematic operators in the expression. Select a category of functions from the Categories list box to display the available functions in that category. In the Functions list, select the function that you want to use in the expression. (Available only on the Advanced Compute) 4. If you want to display the result on the screen without adding it to the Attribute Manager, enable the Single Value check box and proceed to step If you want to include the result in the Attribute Manager, select a field in the Field Name box that will receive the results of the computation or type the name of a new field. 6. In the Field Description box, type a description of the contents of the field. 7. Choose one of the following types of field from the Field Type list: Text: defines the field as a text string Integer: defines the field for positive or negative whole numbers Float: defines the field for single-precision real numbers Double: defines the field for double-precision real numbers 8. Click the Run button. 314

317 If you want to save the equation with the layer, click Save. Opening the Aggregate Attributes dialog box The Aggregate Attributes dialog box is used as a reporting tool or to quickly recombine data for analysis. It combines records based on selected attributes. The output is an unconnected table that contains the results of a specified function or statistical calculation. The Based On criteria is comparable to the Group By clause in an SQL select statement. From the Tools menu in the Attribute Manager, click Aggregate Attributes. From the Layer menu in the Focus main menu, click Aggregate Attributes. Performing a calculation 1. In the Aggregate Attributes dialog box, do any of the following: To use only the selected records in the operation, enable the Aggregate selected shapes only check box. To compute the results based on the shapes that contain the same style in the Representation Editor, enable the Representation values option and select an attribute and function that you want to use. To compute the results based on the records that contain the same attribute values, enable the Attributes option and enable the chck box next to the attribute in the Based On column. Add any function or statistic fields to the output Attribute Manager. For more information, see Adding function fields to output layers on page 320. To add a field containing the number of records used in the calculation, enable the Add a count field check box. 2. Click Aggregate. Opening the Area Neighbors dialog box Area Neighbors is a reporting tool for whole polygon layers, topological polygon layers, and thematic rasters. It generates an unconnected table containing attributes that you can analyse. 1. From the Tools menu in the Attribute Manager, click Area Neighbors. 2. From the Layer menu in the Focus main menu, click Area Neighbors. Reporting bordering areas 1. In the Area Neighbors dialog box, do any of the following: To perform an analysis using only the selected records, enable the Find neighbors to selected input areas only check box. 315

318 To report which shapes border the selected shapes, enable the Adjacent to the input areas option. To include a region outside the boundary of the digitized areas on the layer, enable the Report outside area in result check box. This represents the global polygon or outside area, which appears as -1 in the Attribute Manager. To report in separate records the results of a shape that borders another shape in different places (not available for thematic rasters), enable the Report neighbor B as two records in result check box. For example, the perimeter of shape B touches shape A in two places so you obtain two records for shape B. To report only the shapes that completely surround another shape (for example, lakes containing islands), enable the Input areas surround option. To report shapes that are surrounded by other shapes (for example, islands), click Input areas are surrounded by option. 2. In the Input Areas column, enable the check mark next to the layer attributes that you want to add to the Area Neighbors table. 3. In the Neighbors column, enable the check box next to the layer attributes that you want to add to the Area Neighbors table. If you want to select the records in the Attribute Manager that correspond to the results, enable the Select found neighbors option. 4. Click OK. Creating a chart from the Attribute Manager You can generate a chart from vector, grayscale, and pseudo-color layers in the Maps tree, but not from bitmap (1-bit) or RGB layers. Charts are also available from the Files tree on raster channels or vector segments. When you create a chart, it compares the values of the selected records and fields in the layer attributes, or graphs the pixel value counts from a raster without attributes. For more information about charts, see Viewing data as a chart on page Right-click a layer that contains the data that you want to chart and click Attribute Manager. If you want to chart the pixel value counts from a raster without attributes, you will have to create default attributes. When the message displays, click OK to create the attributes. 2. In the Attribute Manager, select the fields and records that you want to chart. 3. In the main menu of the Attribute Manager, click Tools. 4. Click Charts and choose a chart type. For more information about the Chart viewer, see Using the Chart Viewer on page

319 Opening the Z-value Transfer dialog box If you have a Z-value as an attribute for a shape on an Unstructured, Line, Point, Whole Polygon, or Topological Line vector layer, you can transfer that value to the shape#s vertices. Conversely, you can also convert the Z-values from the shape#s vertices into an attribute. The values for the vertices are not directly associated to the attributes. If you change the Z-values for the attributes, it will not automatically update the vertices, and vice versa. If you want to update either the vertices or the attributes, you must repeat the Z-value transfer. You can view the vertices of a shape with the Vertices tool available in the Vector Editing toolbar (see Adding and removing: vertices on page 329 ). From the Edit menu in the Attribute Manager, click Z-value Transfer. Transferring Z-values from the vertices to a field 1. If you want to transfer the Z-value for the selected records only, enable the Transfer Z-value of selected shapes only check box. 2. Click Shape to attribute. 3. In the Destination field list, click the field that you want to receive the Z-value. If you want to create a new field in the Attribute Manager, click New Field. A default label called Z-value is displayed in the Destination field list. You can rename the label to one of your choice. The field properties, except the data type, are set by default. You set the data type in step 4. To modify the field properties, see Setting the field definitions on page If you create a new field for the Z-value, the Type list becomes available. In the Type list, click one of the following data types: Integer: defines the field for positive or negative whole numbers Float: defines the field for single-precision real numbers Double: defines the field for double-precision real numbers 5. In the Z-value aggregation list, click the method that you want to use to combine the Z-values from the vertices into an attribute for the shape. Click one of the following methods: First: for each selected shape it uses the Z-value from the first vertex as the attribute. Last: for each selected shape it uses the Z-value from the last vertex as the attribute. Sum: for each selected shape it calculates the sum of the Z-values from the vertices and uses that value as the attribute. Mean: for each selected shape it calculates the average Z-value from the vertices and uses that value as the attribute. The average is obtained by adding values from the vertices and dividing that value by the number of 317

320 vertices used in the sum. Minimum: for each selected shape it uses the lowest Z-value from the vertices as the attribute. Maximum: for each selected shape it uses the highest Z-value from the vertices as the attribute. Mode: for each selected shape it calculates the Z-value that occurs the most frequently among the vertices and uses that value as the attribute. Median: for each selected shape it ranks the Z-values from the vertices in numerical order. The median is the middle value and it uses that value as the attribute. Standard Deviation: for each selected shape it measures the variation in the distribution of Z-values, which is calculated from square root of the variance, and uses that value as the attribute. 6. Click Transfer. Transferring Z-values from a field to the vertices 1. If you want to transfer the Z-value for the selected records only, enable the Transfer Z-value of selected shapes only check box. 2. Click Attribute to shape. 3. In the Z-value field list, click the field that contains the Z-values that you want to copy to the vertices. 4. Click Transfer. Exporting layer attributes to a file 1. From the Layer menu in the Attribute Manager, click Export Attributes. 2. In the Export Attributes dialog box, enable any of the following check boxes: Save selected shapes only - saves only selected records in the layer Save selected fields only - saves only selected fields in the layer 3. In the Output area, choose a file from the File list box. If a file is not listed, click Browse, locate and select a file, and click Save. 4. Choose a file format from the Format list box. If you want to modify the file format, click Options and make any changes in the GDB Options Editor. 5. Choose a layer from the Layer list box. 6. Click Save. Exporting the attributes to a text file You can convert data in the Attribute Manager to an ASCII delineated text file using the Export to Text dialog box. 1. From the Layer menu in the Attribute Manager, click Export to Text. 318

321 2. In the Export to Text dialog box, enable one of the following options: Entire Table: exports the whole Attribute Table Visible Region: exports only the displayed records and fields If you want to export specific records and fields, choose a range of records next to Row and choose a range of fields next to Column. 3. Click OK. Opening GeoRasters from the Attribute Manager A table in Oracle 10g Spatial can contain a large number of records of geospatial data. Images stored in Oracle 10g Spatial are called GeoRasters. Since opening a large number of GeoRasters can take a significant amount of time, it may be more efficient for you to open only their footprints. A footprint is a vector representation of the spatial extents of the GeoRaster. By viewing the footprints, you can make a more informed decision on which GeoRasters to open and, therefore, save you some time. GeoRasters are represented by a camera icon in the Attribute Manager. If a red cross appears on the camera icon, it means that the GeoRaster is not available. 1. From the GeoRaster column in the Attribute Manager, right-click a camera icon. 2. Click Add to Area. Dissolving a boundary Dissolve combines shapes that contain the same value for a selected attribute. The resulting output is a layer that contains the newly combined shapes with each shape represented as a layer record. 1. From the Analysis menu in the Focus window, click Dissolve. 2. In the Dissolve dialog box, choose a file from the File list in the Input area. If a file is not listed, click Browse, locate and select a file, and click Open. If you choose Active Layer, the dissolve is performed on the current layer. 3. In the Output area, enable one of the following options: Display: displays the results without saving the new layer Save: saves the new layer in the project. Choose a file from the File list box and choose a layer from the Layer list box. If you want to display the results in the view pane, enable the Display saved results check box. If you want to use only the selected records, enable the Dissolve selected shapes only check box. 4. In the Dissolve Option dialog box, enable one of the following options: Only adjacent shapes: combines all shapes that share a common border and contain the same value for the selected attribute or RST style All shapes: forms one record for all the 319

322 shapes on the layer that contain the same value for the selected attribute or RST style If you want to combine the adjacent pixels that are diagonal to each other and that contain the same value for the selected attribute or RST style for thematic rasters, enable the Pixels that meet at a diagonal check box. 5. In the Dissolve Method area, enable one of the following options: Representation Values: removes boundaries between shapes that contain the same key for the representation of the layer Attributes: removes boundaries between shapes that contain the same attribute values 6. In the Based on column, enable the check box next to the attributes you want to include. If you want to add a field containing the number of shapes combined to form each record in the output, enable the Add a count field check box. 7. Click OK. For information about adding function or statistic fields to the output Attribute Manager, see Adding function fields to output layers on page 320. Adding function fields to output layers When you use Aggregate Attributes, Dissolve, or Statistical Overlay, you can add statistic and function fields to the output layer Attribute Table, or both. For more information, see Opening the Aggregate Attributes dialog box on page 315, Dissolving a boundary on page 319, and Using a statistical overlay on page 333. You can add fields using the simple or advanced methods. With the simple method, you can add only one new field per attribute. With the advanced method, you can add several fields per attribute. The statistic fields, Mean, Minimum, Maximum, Mode, Median, and Standard Deviation, are described in Setting a selected record statistics display on page 306. To add fields using the simple method From the Function column, click in an attribute cell and choose a function or statistic. To add fields using the advanced method 1. Click Advanced. 2. Click in a column for the attribute. A check mark indicates the selected functions and statistics. If you want to calculate the weighted average, click in the Weighted Avg column next to the attribute that you want to use in the calculation and choose an attribute. Working with shapes You can use the Selection tools in the view pane and in 320

323 the Symbol Editor to select, group, and attach shapes. Selecting a single shape When you select a shape in the view pane, its record is also selected in the Attribute Manager. To select a record in the Attribute Manager, see Selecting and clearing records and fields on page From the Editing toolbar in the Focus window, click the Selection Tools arrow and choose Individual. 2. Click the shape that you want. If you want to select another shape, press Shift and click a shape. Selecting shapes within or partially within a circle 1. From the Editing toolbar in the Focus window, click the Selection Tools arrow and choose Circular. 2. Drag a circle over a location in the view pane. If you want to add more shapes to your selection, press Shift and drag another circle. Selecting shapes within or partially within a polygon 1. From the Editing toolbar in the Focus window, click the Selection Tools arrow and choose Area. 2. Click in the view pane for each vertex you want included in the area. 3. Double-click the last vertex. All the shapes that are inside or that touch the polygon are selected. If you want to add more shapes to your selection, press Shift and digitize another polygon. Grouping shapes Grouping ties shapes from the same layer to act as a single unit. Each shape in a group maintains its original representation and attributes. You cannot select or modify grouped shapes individually; however, you can change individual attribute values in the Attribute Manager. When you group shapes, a new field labeled GroupId is added to the Attribute Manager. Focus assigns each record in the group the same GroupId number. 1. Select the shapes you want to group. 2. From the Edit menu in the Focus window, click Group. Ungrouping shapes 1. Select the grouped shapes that you want to separate. 2. From the Edit menu in the Focus window, click Ungroup. 321

324 Attaching shapes Attaching combines shapes from the same layer into one record. The shapes appear as grouped in the view pane, but the records for the attached shapes are unified in a record in the Attribute Manager. You can attach adjacent shapes, non-adjacent shapes, and shapes that are contained within other shapes. Attached shapes are referred to as rings. You can use rings when separate shapes form a single entity, such as a collection of islands forming one county, or when shapes are contained within other shapes, such as an island in a lake. 1. Make sure the items are on the same layer. 2. Select the items you want to attach. 3. From the Edit menu, click Attach. Separating shapes 1. Select the attached items. This can be accomplished using the Attribute Manager, by clicking on a group member, through a window selector, or a query. 2. From the Edit menu, click Detach. Creating buffers A buffer is a margin created at a specific distance around shapes on a layer. You can create margins of different sizes, each referred to as a buffer level.you use buffer levels to analyse suitability or risk around the input shapes, which is referred to as a proximity analysis. For example, you can create a buffer around domestic wells to analyse the risk of contamination from pesticide use. From the Analysis menu, click Buffer. Creating buffers - step 1 1. In the Input area, choose a file from the File list box. If a file is not listed, click Browse, locate and select a file from the File Selector dialog box, and click Open. 2. Choose a layer from the Layer list box. 3. In the Output area, enable one of the following options: Display: shows the results without saving the new layer Save: saves the new layer to the project. Choose a file from the File list box and choose a layer from the Layer list box. If you want to display the results in the view pane, enable the Display saved results check box. If you want to include only the selected records in the layer, enable the Buffer selected shapes only check box. 322

325 4. In the Buffer Distances area, enable one of the following options: Simple: buffers all the selected shapes Representation Values: buffers the selected shapes according to their representation values Field: buffers the selected shapes according to an attribute. Choose an attribute from the list box. 5. Enter a number of levels that you want in the Buffer levels spin box. 6. Choose a unit of measurement from the Units list box. 7. In the Buffer distances table, type a number in each Level column to determine the width of a buffer. 8. Click Next. Creating buffers - step 2 1. In the Vertex Options area, enable a cornering type. 2. In the Line Options area, enable an option for the side you want the buffer to appear. 3. Enable an End style option for the style you want to use at the end of lines. 4. In the Polygon Options area, enable a style option. 5. In the Fields to Add area, enable the SourceShapeId check box. 6. Enable any of the following check boxes: [attribute name]value: includes the attribute values in the output layer if the buffer is based on an attribute and if overlapping buffers are kept separate BufferDistance: lists the width of the buffer for each level in the output layer BufferLevel: lists the levels in the output layer 7. In the Output Areas area, enable one of the following options: Combine: combines the shapes where the buffers overlap Keep Separate: keeps each buffer separate 8. Click Finish. Editing vectors using the vector editing tools You can access the vector editing tools and the Vector Editing Tools toolbar from the Edit menu. A variety of tools are provided for editing vectors. Some of the changes that you can make using the vector editing tools can affect the attributes of the shape you are editing. For example, the Merge Line/Polygon tool combines two shapes, including their attributes. When you edit vectors in a Math Model Area (see Understanding vector editing in a math model area on page 302 ), the vertices are shown in the correct position according to the math model and DEM, or the approximate elevation value that you provided when you created the Area. Lines connecting the vertices are straight and do not reflect the effects of the math model and elevation. 1. Click a shape with the Individual Selection tool. 2. From the Edit menu, click Vector Editing. The vector editing tools on the Edit menu become 323

326 available and the Vector Editing Tools toolbar are displayed. About the Vector Editing tool bar The following table shows the available tools. Table 21. Vector Editing tools Tool Name Action Find Reverse Vertices Add Vertices Merge Line/Polygon Split Line/Polygon Selects the shape and Identifies the start and end vertices. Changes line direction (not available for whole polygons). Creates new vertices within a shape. Connects ends of lines together or combines polygons by removing common boundaries. Breaks lines and polygons into Tool Name Action Extend Line Auto Merge Line Close Shape Mirror Tools Rotation Tools Break Line/Polygon Start Vertex separate shapes. Extends the length of a vertex in a straight line. Removes the start or end vertices shared between lines (pseudo-nodes) Automatically connects the start and end vertices of a line to form a polygon. Flips a shape horizontally or vertically to make a mirror image. Rotates a shape around an anchor. Separates overlapping shapes at their intersecting points. Moves the cursor to the start vertex in a selected 324

327 Tool Name Action Previous Vertex Midpoint Next Vertex End Vertex Show Vertex Vertices shape. Moves the cursor from one vertex to the previous vertex in a selected shape. Moves the cursor halfway between two vertices in the direction of the line. Moves the cursor from one vertex to the previous vertex in a selected shape. Moves the cursor to the end vertex in a selected shape. Makes the vertices in a shape more prominent for better visibility. Opens the Vertices dialog box and displays the vertex coordinates of a selected shape. Selecting a shape The Find tool selects a shape and identifies the start and end vertices. 1. On the Vector Editing Tools toolbar, click the Find button. 2. Click a shape. Moving a vertex The Find tool selects a shape and identifies the start and end vertices. 1. On the Vector Editing toolbar, click the Find button and click a shape. 2. Click the Show Vertices button. 3. Drag a vertex to a new location. Moving several vertices together while maintaining their form The Find tool selects a shape and identifies the start and end vertices. 1. On the Vector Editing Tools toolbar, click the Find button and click a shape. 2. Click the Show Vertices button. 3. Press and hold the Ctrl key and select several vertices 4. Drag a selected vertex to a new location. 325

328 Reversing vector direction The Reverse Vertices tool changes the direction of the line (not available for whole polygons). 1. From the Vector Editing Tools dialog box, click the Find button and click a shape. 2. Click the Reverse Vertices button. Adding vertices The Add Vertices tool creates new vertices within a shape. When you use this tool in a Math Model Area (see Understanding vector editing in a math model area on page 302 ), the elevation for the new vertex is derived from the DEM or the approximate elevation value that you provided when you created the Area. 1. From the Vector Editing Tools dialog box, click the Find button and click a shape. 2. Click the Add Vertices button. 3. Click on the line where you want the vertex. If you want to continue a line, click the start or end vertex of the line and click a series of vertices. Connecting lines The Merge Line/Polygon tool connects ends of lines together or combines polygons by removing common boundaries. This tool may affect the attributes of the shape you are editing. 1. From the Vector Editing Tools dialog box, click the Find button and click a line. 2. Click the Merge Line/Polygon button. 3. Click the start or end vertex of the line. 4. Click the start or end vertex of a line with which you want to merge the first line. Connecting polygons 1. Click the Find button and click a polygon. 2. Click the Merge Line/Polygon button. 3. Click a polygon with which you want to merge the first polygon. Cutting a line The Split Line/Polygon tool cuts lines and polygons into separate shapes. This tool may affect the attributes of the shape you are editing. When you use this tool in a Math Model Area (see Understanding vector editing in a math model area on page 302 ), the elevation for the new vertex created at the cut point is derived from the DEM or the approximate elevation value that you provided when you created the Area. 1. From the Vector Editing Tools dialog box, click the Find button and click a line. 2. Click the Split Line/Polygon button. 3. Click where you want to split the line. 326

329 When you split a polygon, you draw a line through the shape where you want the polygon to split. Cutting a polygon 1. Click the Find button and click a polygon. 2. Click the Split Line/Polygon button. 3. Click a point on the outline of the polygon where you want to begin a line. 4. Click in the polygon to form the line. 5. Double-click a point on the outline of the polygon to end the line. Extending a line You can move a start or end vertex simply by selecting the vertex with the Find tool and moving it. However, if you want to extend the line without changing its angle, the Extend Line tool forces the vertex to move in a straight line. When you use this tool in a Math Model Area (see Understanding vector editing in a math model area on page 302 ), the elevation for the new vertex is derived from the DEM or the approximate elevation value that you provided when you created the Area. 1. From the Vector Editing Tools dialog box, click the Find button and click a line. 2. Click the Extend Line button. 3. Click a start or end vertex. 4. Click where you want to end the extension. Merging segmented lines The Auto Merge Line tool removes the start or end vertices shared between lines (pseudo-nodes). If a line#s start and end vertices connect, it automatically forms a polygon. This tool may affect the attributes of the shape you are editing. 1. From the Vector Editing Tools dialog box, click the Find button and click a line. 2. Click the Auto Merge Line button. 3. Click the start or end vertex where you want to begin merging the line. If it reaches a fork in the line, you must choose which line to follow. Click the line that you want to merge. Changing a line into a polygon The Close Shape tool automatically connects the start and end vertices of a line to form a polygon. 1. From the Vector Editing Tools dialog box, click the Find button and click a line. 2. Click the Close Shape button. Flipping a shape to its mirror image The Mirror tools flip the shape horizontally or vertically resulting in the mirror image of the shape. When you use this tool in a Math Model Area (see 327

330 Understanding vector editing in a math model area on page 302 ), the shape is flipped according to the ground coordinates and may be mirrored about oblique axes, which may cause the it to appear distorted. To flip a shape 1. From the Vector Editing Tools dialog box, click the Find button and click a shape. 2. Click the Mirror Tools button. To switch the Mirror tools from horizontal to vertical 1. Click the Mirror Tools arrow and choose one of the following: Mirror X: flips a shape vertically Mirror Y: flips a shape horizontally Spinning a shape free hand The Rotation tools revolve a shape around an anchor. By default, the start vertex is the anchor when a Rotation tool is selected. To move the anchor, click it and move it. When you use this tool in a Math Model Area (see Understanding vector editing in a math model area on page 302 ), the elevation for each vertex in the shape is derived from the DEM or the approximate elevation value that you provided when you created the Area. 1. From the Vector Editing Tools dialog box, click the Find button and click a shape. 2. Click the Rotation Tools arrow and click Free Rotate. 3. Drag the shape to the angle you want. Spinning the shape precisely 1. Click the Find button and click a shape. 2. Click the Rotation Tools arrow and click Rotate by Angle. 3. In the Rotate by Angle dialog box, enter a value for the angle by which you want to rotate the shape in the spin box. 4. Choose an angle unit from the list box. 5. Click OK. Separating overlapping shapes The Break Line/Polygon tool separates overlapping shapes at their intersecting points. For example, if you have two overlapping polygons, the Break Line/Polygon tool separates the two polygons into three with the overlap area becoming the third polygon. This feature is not available for a topological layer, because overlapping shapes are automatically separated. This tool may affect the attributes of the shape you are editing. 1. From the Vector Editing Tools dialog box, click the Find button and click a shape. 2. Click the Break Line/Polygon button. 3. Click the overlapping shape outside of the overlap area. Moving the cursor to the start vertex 328

331 You can select a vertex by clicking it or you can use one of the navigation tools. Start Vertex and End Vertex Moves the cursor to the start vertex or end vertex of a selected shape. 1. From the Vector Editing Tools dialog box, click the Find button and click a shape. 2. Click the Start Vertex button. Moving the cursor to the end vertex: 1. Click the Find button and click a shape. 2. Click the End Vertex button. Previous Vertex and Next Vertex Moves the cursor from one vertex to another in a selected shape. The Previous Vertex tool moves the cursor toward the start vertex; the Next Vertex tool moves the cursor toward the end vertex. Moving the cursor along vertices 1. Click the Find button and click a shape. 2. Click the Previous Vertex button or the Next Vertex button. Midpoint TMoves the cursor halfway between two vertices in the direction of a line. Moving the cursor to a vertex 1. Click the Find button and click a shape. 2. Select a vertex. 3. Click the Midpoint button. Displaying vertices The Show Vertices tool makes the vertices in the shape more prominent so they more easily seen. 1. From the Vector Editing Tools dialog box, click the Find button and click a shape. 2. Click the Show Vertices button. Adding and removing: vertices To display coordinates, select a shape with the Find tool and click the Vertices button. The Vertices dialog box displays the coordinates of the vertices contained in the selected shape. If you select a vertex in the view pane and move it, the coordinates are automatically updated. You can also add or subtract vertices from the Vertices dialog box. When you add a vertex, it is inserted halfway between the selected vertex and the next according to the direction of the line. 329

332 1. Select a vertex in the Vertices dialog box and do the following: To add vertices, click the Add button. To delete a vertex, click it and click the Remove button. The coordinate system for the Area in the Maps tree is determined by the first layer opened in the Area. When you add layers to the Maps tree, you have the choice of using the same coordinate system or a different one. If the coordinate system for the layer is different than that of the Area, you can display the coordinates of the vertices in either systems. Switching between coordinate systems 1. To view the vertices using the coordinate system of the Area in the Maps tree, click Area under Coordinate System. 2. To view the vertices using the coordinate system of the layer, click Layer under Coordinate System. Selecting vectors using spatial query tools Spatial Query tools search through all visible layers to select the shapes that correspond to your criteria. Including an original selection in a spatial query When you use any of the Spatial Query tools, you can include or exclude your original selection from the resulting selection. When you enable the Add to Selection option, the results of the Spatial Query are selected along with your original selection. When you clear Add to Selection, only the results of the Spatial Query are selected. From the Editing toolbar, click the Spatial Query arrow and choose Add to Selection. A check mark next to the option indicates it is enabled. Selecting fully contained shapes The Fully Within tool selects all other shapes that fall completely within a selected shape or area. Any shape that touches or overlaps a shape other than the one you selected will not be included. 1. From the Editing toolbar, click the Selection Tools arrow and choose a tool. 2. Click a shape or select an area. 3. From the Editing toolbar, click the Spatial Query arrow and choose Fully Within. Selecting partially contained shapes The Partially Within tool selects the shapes that have at least one vertex in common with a selected shape or area, including overlapping and neighboring shapes. 330

333 1. From the Editing toolbar, click the Selection Tools arrow and choose a tool. 2. Click a shape or select an area. 3. From the Editing toolbar, click the Spatial Query arrow and choose Partially Within. Selecting all shapes within a specified distance The Within Distance tool selects shapes that fall completely or partially within a specified distance of a select shape or area. If you do not select a shape or area, the distance is calculated from the location of the cursor. 1. From the Editing toolbar, click the Selection Tools arrow and choose a tool. 2. Click a shape or select an area. 3. From the Editing toolbar, click the Spatial Query arrow and choose Within Distance. 4. In the Within Distance dialog box, type a number in the Distance box. 5. Choose a unit of measurement from the list box. 6. Click OK. Selecting all shapes fully within a distance The Fully Within Distance tool selects only shapes that fall completely within a specified distance of a selected shape. If you do not select a shape, the distance is calculated from the location of the cursor. 1. From the Editing toolbar, click the Selection Tools arrow and choose a tool. 2. Click a shape or select an area. 3. From the Editing toolbar, click the Spatial Query arrow and choose Fully Within Distance. 4. In the Within Distance dialog box, type a number in the Distance box. 5. Choose a unit of measurement from the list box. 6. Click OK. Selecting intersecting shapes The Crosses tool selects all of the shapes that intersect selected shapes. 1. From the Editing toolbar, click the Selection Tools arrow and choose a tool. 2. Click a shape or select an area. 3. From the Editing toolbar, click the Spatial Query arrow and choose Crosses. About the Overlay wizard An overlay derives information from two or more input layers. The Overlay Wizard contains three overlay types: Spatial Overlay, Statistical Overlay, and Suitability Overlay. Spatial Overlay forms a new layer containing the attributes from two or more layers. For more information, see Combining layers with a spatial overlay on page 332. Statistical Overlay transfers the selected attributes from layer to another. For more information, see Using a statistical overlay on page

334 Suitability Overlay analyses the relative importance of input layers and attributes to identify the areas that produce the most positive result. For more information, see Using a suitability overlay on page 334. Combining layers with a spatial overlay Spatial Overlay forms a new layer containing the attributes from two or more layers. For example, you can overlay a layer containing land-ownership polygons and a layer containing vegetation polygons to analyse where the types of vegetation are located on each property. If you want to overlay specific shapes from the layers, select them before you begin the Spatial Overlay. 1. From the Analysis menu, click Overlay. 2. In the Overlay Wizard, enable the Spatial option and click Next. 3. In the Available Files/Layers list, enable the check mark next to the layers that you want to combine. If you want to select layers from another file, click Browse, locate and select a file from the File Selector dialog box, and click Open. If you want to overlay only the selected shapes in each layer, enable the Overlay only the selected shapes of the input layers check box. 4. Click Next. 5. Choose a layer from the Layer list box. 6. Select an attribute that you want to include in the new layer from the Input Attribute list. 7. Click Add. 8. Repeat step 5 to step 7 for each layer. If you want to change the order of an attribute, select it in the Attribute table and click the up or down arrow buttons. 9. If you want to change the names of an attribute, double-click it and type a new name. 10. Click Next. 11. In the Output Options area, enable one of the following options: Union: includes all shapes in their entirety from all the input layers Intersection: includes only the overlapping areas of the shapes from the input layers 12. Enable any of the following check boxes: Use a Mask to Limit Output: uses a layer to limit the area. Choose a layer from the list box. Using Only Selected Shapes: includes only the selected shapes as the mask Use a Named Region to Limit Output: uses an existing named region as the mask. For more information about Named Regions, see Creating named regions on page In the Output Layer area, select a layer type for the new layer from the Type list box. 14. Enable one of the following options: Display: shows the results without saving the new layer Save: saves the new layer in the project. Choose a file from the File list box and choose a layer from the Layer list box. If you want to display the results in the view pane, enable the Display saved results check box. 15. Click Finish. 332

335 Using a statistical overlay Statistical Overlay transfers the selected attributes from one layer to another. One layer, called the Primary Input, receives the attributes from another layer, called the Secondary Input. There are two possible results when you transfer attributes between the layers: Each shape in the Primary Input can receive the attributes from one shape in the Secondary Input. For example, you can transfer the county attributes from a county layer to a cities layer. Each city in the Primary Input receives the attributes from the county that contains the city. Each shape in the Primary Input can receive the attributes from many shapes in the Secondary Input. You must specify a function to aggregate the attributes from the Secondary Input. For example, you can transfer the city attributes from a cities layer to a county layer. Each county in the Primary Input receives the sum of the population of the cities contained within that county. 1. From the Analysis menu, click Overlay. 2. In the Overlay Wizard, enable the Statistical option and click Next. 3. In the Primary Input area, choose a file from the File list box. If a file is not listed, click Browse, locate and select a file from the File Selector dialog box, and click Open. 4. Choose a layer that will receive the attributes from the Layer list box. If you want to include only the selected records in the layer, enable the Use selected shapes only check box. 5. In the Secondary Input area, choose a file from the File list box. 6. Choose a layer that contains the attributes you want to add to the Primary Input layer from the Layer list box. If you want to include only the selected records in the layer, enable the Use selected shapes only check box. 7. Click Next. 8. Click Finish. You can add function fields to the output Attribute Manager. (See Adding function fields to output layers on page 320 ) You can also add fields containing other attributes. (See Adding attributes to the statistical overlay output on page 333 ) Adding attributes to the statistical overlay output The Primary and Secondary Input layers that you choose for the Statistical Overlay determine the availability of the Grouping Criteria options and the options available under Additional Attributes. Count 333

336 is available when: The Primary Input is a line layer and the Secondary Input is a line, polygon, thematic raster, or raster. The Primary Input is a polygon layer and the Secondary Input is a point, line, polygon, thematic raster, or raster. The Primary Input is a thematic raster layer and the Secondary Input is a point, line, polygon, thematic raster, or raster. When you enable the Count check box, Focus calculates the number of shapes combined to form each record and adds that attribute the output layer. Surface Length is available when the Primary Input is a line layer and the Secondary Input is a raster. This option is useful if the raster is a DEM. When you enable the Surface Length check box, Focus calculates the three-dimensional surface length of the line and adds that attribute the output layer. Distance is available when: The Primary Input is a point layer and the Secondary Input is a point, line, or polygon layer. The Primary Input is a line layer and the Secondary Input is a points layer. When you enable the Distance check box, Focus identifies the shape from the Secondary Input that is the closest to each shape in the Primary Input and calculates the distance between them. The distance is added to each record in the output layer. When points are contained within the polygon, the distance equals zero in the output. Counting Specific Pixel Values: You can count specific pixel values when the Primary Input is a line, polygon, or thematic raster layer and the Secondary Input is a raster. For each line in the Primary Input, Focus identifies corresponding pixels in the Secondary Input and adds that attribute the output layer. Grouping Criteria: The Grouping Criteria options are available when the Primary Input is a polygon layer and the Secondary Input is a line or polygon layer. To combine all shapes from the Secondary Input that touch or overlap the boundaries of each shape in the Primary Input, enable the Partially Within option. The resulting attribute is added to the output layer. To combine only the shapes from the Secondary Input that lie entirely within the boundaries of each shape in the Primary Input, enable the Wholly Contained option. The resulting attribute is added to the output layer. Using a suitability overlay Suitability Overlay analyses the relative importance of various data to identify areas that produce the most 334

337 positive result. For example, analysing data in a project to identify the best location for a school or the most likely location for a forest fire. To perform the analysis, you must build a project containing layers of data that you want to use in the calculation. Each layer should contain one type of data representing a factor in the calculation. For example, if you are trying to determine the best location for a winery, your project could contain a layer with rainfall levels for an area, a layer of soil types found in the area, a layer containing the road network, and so on. To calculate a combination that produces the best result, you must decide on a scale to rank the importance the layers and a scale to rank the data in the layers. The scales measure the relative importance of each input into the equation; the most important factors affect the results the most. The value from the scale that you assign to the layer and to the data is called a weight. For more information about how to determine the scales, see Understanding weights in the suitability overlay on page 336. For example, you have a scale of 1 to 100 for the layers. Because the soil type layer is more important than the road network layer, you can assign a weight of 75 to the soil type layer and a weight of 25 to the road network layer; the soil type layer is three times more influential in the calculation than the road network layer. You do not need to use the same scale for the layers and the data in the layers, but you should use one scale for the layers themselves and one scale for the data in the layers. Weighting the data in one layer according to a vastly different scale from the data in the other layers can skew the results. To add weights to data, add a field in the Attribute Manager for each layer and enter the numeric value expressing the weight for the data in each record. A negative weight for a record will force an unfavorable result in the output for that record. For example, you have a scale of 1 to 10 for the data in the layers. In the soil type layer, you assign the well-drained soils an 8, the poor and shallow soils a 2, and the polluted soils a -1. Any sites containing polluted soils will automatically receive a negative result. You must also assign a weight to the'no Data' value in the layers. The'No Data' value represents the null values or the pixels without data. The'No Data' value is usually set in the metadata of the layer so it may not appear in the Attribute Manager. When you assign a weight to the'no Data' value in step 7, you should use the same scale as the rest of the data in the layers. When setting up a Suitability Overlay, you must determine the weight of each layer, the weight of the NoData value, and select the field that contains the weights for the data in each layer. The result is displayed in a layer indicating the most positive correlation between all the factors in the equation. 1. From the Attribute Manager, add a field to each layer containing the numeric value expressing the weight of the records. For more information, see 335

338 Adding new fields on page From the Analysis menu in the Focus window, click Overlay. 3. In the Overlay Wizard, enable the Suitability option and click Next. 4. In the Available Files/Layers list, enable the check mark next to the layers that you want to combine. If you want to select layers from another file, click Browse, locate and select a file from the File Selector dialog box, and click Open. 5. Click Next. 6. Type a number to determine the weight of each layer in the Layer Weight column. 7. Type a number to determine the weight of NoData value for each layer in the NoData Weight column. Use the same weight scale as you used for the attributes. 8. In the Attribute Weight column, click a cell and choose the weight values for the attributes. 9. Click Next. 10. In the Output Options area, enable one of the following options: Union: includes all the shapes in their entirety from all input layers Intersection: includes only the overlapping areas of shapes from the input layers 11. Enable any of the following check boxes: Use a Mask to Limit Output - uses a layer to limit the area. You can use an existing a bitmap, raster, or polygon layer. Choose a layer from the list box. Using Only Selected Shapes - includes only the selected shapes as the mask Use a Named Region to Limit Output - se an existing named region as the mask. For more information about Named Regions, see Creating named regions on page In the Output Layer area, enable one of the following options: Display - shows the results without saving the new layer Save - saves the new layer in the project. Choose a file from the File list box and choose a layer from the Layer list box. If you want to display the results in the view pane, enable the Display saved results check box. 13. Click Finish. Understanding weights in the suitability overlay The range of numbers that you select for a scale does not have an inherent value; it is the degree of value in the scale that gives them their value. For example, if you use a scale of 1 to 10 and assign a weight of 2 to the Road Network layer and a weight of 5 to the Rainfall layer, it has the same effect as using a scale of 1 to 100 and giving Road Network layer a weight of 20 and the Rainfall layer a weight of 50. In each case, the Rainfall layer has more weight and is considered better or more desirable in the calculation. The scale for the layers is usually based on a scale of 1 to 100, but the sum of the layer weights does not need to equal 100. The point is to identify the relative importance 336

339 of each layer in comparison with the others. The scale of the data in the layers does not have to be the same as that used for the layers, but the scale should be consistently applied for all the data. Using different scales for the data in different layers may cause unwanted results. For example, if you used a scale of 1 to 1000 to rank the data in the Soil Types layer and a scale of 1 to 10 for the data in the other layers, the soil types might nullify the importance of other data like rainfall even if the Rainfall layer itself has a higher weight than the Soil Type layer. Viewing data as a chart Charts are a way to visualize your data. A chart is a table of attributes displayed as a graphic where the values of selected records and fields are compared. It displays quantitative data so you can see how the numbers relate to each other, which helps you to interpret the information more easily. Trends or anomalies may become evident when displayed using the right chart type. For example, it may be difficult to identify trends by looking at a table filled with population statistics, but with the right chart the pattern become easily discernable. For column, bar, line, area, and pie chart types, you must select at least one field and one record before the chart is displayed in the viewer. For the scatter chart type, the minimum number of selected records and fields depends on the Series in setting. When Series in is set to Records, you must select at least two fields and at least one record before the chart is displayed. When Series in is set to Fields, at least one field and at least two records must be selected. If the minimum number of selected records and fields for any chart type is not satisfied, the chart displays a message reminding you to select data. You can create more than one chart per layer. Each chart is connected to the attributes in the layer so if the attribute values change, the chart changes to reflect the new values. Each chart that you create is remembered in the Chart Manager. For more information, see Opening and deleting a chart on page 348. About chart types The trick with charts is to use the right chart type to display your data. One chart type can make your data instantly understandable while another can completely confound it. Column: The column chart type displays the selected data as vertical stripes of different colors or patterns. The categories are organized along the x-axis (horizontally) and the values are measured along the y-axis (vertically). Column charts are often used to compare data or to emphasize how data changed over time. Three options are available for the column chart: The Clustered Column type forms separate bands for each kind of data and groups the bands side-by-side by category. The Stacked Column type forms bands for each 337

340 kind of data and piles the bands on top of one another to form one column per category. The 100% Stacked Column type is similar to the Stacked columns type, except each band is expressed as a percentage and each column totals 100%. The Stacked columns and Percent columns illustrate the contribution of each band to the whole category. Bar: The bar chart type displays the selected data as horizontal stripes of different colors or patterns. In contrast with the column chart type, the values are organized along the x-axis (horizontally) and the categories are measured along the y-axis (vertically). Bar charts are often used to compare data while reducing the emphasis on the passage of time. Three options are available for the bar chart: The Clustered Bar type forms separate bands for each kind of data and groups the bands side-by-side by category. The Stacked Bar type forms bands for each kind of data and lines up the bands end to end to form one column per category. The 100% Stacked Bar type is similar to the Stacked bar type, except each band is expressed as a percentage and each column totals 100%. The Stacked bar and Percent bar charts illustrate the contribution of each band to the whole category. Line: The line chart displays the selected data as lines of different colors or patterns connecting points at equal intervals. The categories are organized along the x-axis (horizontally) and the values are measured along the y-axis (vertically). The vertices represent the values for each category and the angles formed by the lines connecting the vertices emphasize the trends. Three options are available for the line chart: The Line type creates a line for each kind of data where each vertex represents the actual value for each category. The Stacked Line type creates a line for each kind of data where each vertex represents the value of each category added to the value of the vertex beneath it. Therefore, the topmost vertex in each category reflects the sum total of all the data in that category. The 100% Stacked Line type is similar to the Stacked line type, except each line is expressed as a percentage and each category totals 100%. The Stacked line and Percent line types illustrate the contribution of each line to the whole category. Area: The area chart displays the selected data as polygons of different colors or patterns connecting points at equal intervals. It is similar to the line chart, except the area below the line is shaded to form a polygon. The categories are organized along the x-axis (horizontally) and the values are measured along the y-axis (vertically). The points represent the values for each category and the angles formed by the lines connecting the points emphasize the trends. 338

341 Three options are available for the area chart: Pie: The Area type creates a polygon for each kind of data where the points represent the actual value for each category. The Stacked Area type creates a polygon for each kind of data where each point represents the value of each category added to the value of the point beneath it. Therefore, the topmost point in each category reflects the sum total of all the data in that category. The 100% Stacked Area type is similar to the Stacked Area type, except each polygon is expressed as a percentage and each category totals 100%. The Stacked Area and 100% Stacked Area types illustrate the contribution of each polygon to the whole category. The pie chart is a circular graphic which displays the data as wedges representing their portion of the whole. It can only show the portions or ratios of one kind of data at a time. Two options are available for the pie chart: The Pie type creates a circle divided into slices proportional to the whole. The Exploded Pie type creates a circle broken into slices proportional to the whole. Scatter: The scatter chart is a graph of points comparing two sets of data. One set is plotted along the x-axis and the other along the y-axis. It is used to uncover a possible correlation between the data sets. The appearance of a discernable pattern or clustering of the points indicates a correlation between the data sets. An indicator of a high correlation between the data sets is that you are able to draw a straight line through the points. The more points that cluster about the implied line, the stronger the possibility of a correlation. If the points appear randomly distributed over the chart, it is unlikely that a correlation exists. It is important to note, however, that although a scatter chart may indicate a correlation between the data sets it does not mean that one data set is causing an affect on the other. The correlation can be the result of a third factor affecting both sets or can be simply a coincidence. Creating a chart from the layer You can generate a chart from vector, grayscale, and pseudocolor layers on the Maps tab, but not from bitmap (1-bit) or RGB layers. Charts are also available from the Files tab on raster channels or vector segments. When you create a chart, it compares the values of the selected records and fields in a layer#s attributes or graphs the pixel value counts from a raster without attributes. 1. In the Maps tree, select the layer that contains the data that you want to chart. 2. If you want to select specific shapes to chart from a 339

342 vector or thematic raster layer, click the Selection Tools arrow on the Editing toolbar and select a tool. In the view pane, click or drag to select the shapes that you want included in the chart. 3. In the Focus main menu, click Layer. 4. Click Charts and select a chart type from the list. 5. In the Chart viewer toolbar, click the Chart Definition button. 6. Select the fields, see Defining the data to chart on page Click OK. Defining the data to chart Depending on which chart type you choose, you need to select a minimum number of records and fields (see About chart types on page 337 ). If the minimum number of selected records and fields for any chart type is not satisfied, the chart displays a message reminding you to select data. 1. In the Type list, select the chart type that you want to use to display your data. For more information on the chart types, see About chart types on page Under Fields, click to select the fields that you want to include in the chart. Only the fields with a black check mark are included in the chart. 3. For Series in, select Fields to display the data from the selected Fields or select Records to display the data from the selected records. For more information, see About Series In on page To customize the look of chart, click the Options tab. For more information, see Designing the chart surround on page Click OK. About Series In The Series In option on the Chart Definitions dialog box defines what is displayed in the graph. Depending on what you want the data to be interpreted, you may want to emphasize either the records or the fields. When you select Records, the data in each record is represented in the chart. When you select Fields, the data is displayed by field in the chart. For example, when you choose Fields for the chart shown in the following figure, the fields are displayed as bars (Pop2000 and Pop2002). When you choose Records, the records (Alaska, California, and Florida) are displayed as bars. 340

343 meaning of the data displayed in a chart. It puts the data into context so we can analyse, organize, and communicate the information effectively. Understanding Series In: Designing the chart surround A chart's purpose is to display data so that we can quickly grasp its meaning. The chart surround is a collection of graphical elements that gives meaning or clarifies the The chart surround elements include: Title and subtitle The x-axis and its ticks, labels and headings The y-axis and its ticks, labels and headings The legend The background The data labels Each chart surround element helps to present the data as clearly as possible. You do not need to include every element in every chart. Select the ones that most effectively convey the chart's meaning. 1. On the Chart Definition dialog box, click the Options tab. 2. In the Title box, type a word or phrase that you want as a title for your chart. 3. In the Subtitle box, type a word or phrase that you want as a subtitle for your chart. 4. In the Category field list, select the field that most clearly describes the records used in the chart. For more information, see About the category field on page In the X-axis heading box, type a word or phrase that you want to display along the bottom of the chart. 6. Select Show X-axis values to display the data values along the x-axis of the chart. 7. In the Y-axis heading box, type a word or phrase that you want to display along the y-axis of the chart. 341

344 8. Select Show Y-axis values to display the data values along the y-axis of the chart. 9. Select Show legend to display the legend for the data in the chart. 10. Select Show data labels to display labels on the data in the chart. 11. In the Background style list, click to select a style for the area behind the chart. You can create a frame around the chart or color the background. For more information about creating styles, see Selecting a style on page Click OK. NOTE: The Restore to Defaults button clears the preference file for the chart, not just the settings on the Options tab. For more information, see Resetting the chart to defaults on page 343. About the category field The Category field list on the Chart Definition dialog box determines which field is used to identify the records used in the chart. It affects what is displayed on the x-axis, the legend, or the y-axis depending on the chart type and the Series in setting. Table 22. Chart Type Series in: Fields Series in: Records Category field displays on: Bar y-axis legend Line x-axis legend Area x-axis legend Category field displays on: Pie legend not displayed Scatter not displayed legend The field that you select depends on what you want to emphasize or what attribute most clearly represents the data in your chart. For example, in the following figure the chart displays the same data: the number of houses and apartments for each newspaper route. If you have new customers to add on Second Avenue which falls along both route 15 and 22, Chart A is going to be less helpful unless you have memorized the names of the couriers responsible for the routes. Chart B, on the other hand, gives you the route number immediately. Understanding the Use of the Category Field Chart Type Series in: Fields Series in: Records Category field displays on: Column x-axis legend Category field displays on: 342

345 Definition button. 2. On the Chart Definition dialog box, click the Options tab. 3. Click Restore to Defaults. 4. Click Apply. Using the Chart Viewer The Chart Viewer consists of a view pane and a toolbar. The view pane contains the chart and the chart surround items. It serves as your workspace for creating your chart. The toolbar provides quick access to various tools and dialog boxes that you can use to design your chart. To select a chart surround element or part of the chart 1. Click the Selection Tool button. 2. Click the item in the viewer. Resetting the chart to defaults When you create your first chart, the look of the chart is set by default. As you select the colors, fonts, and other design options, Focus retains your choices in a preference file so the next time you create a chart, the last used styles are applied to your current data. If you click the Restore to Defaults button on the Chart Definition dialog box, it clears the preference file for the chart, not just the settings on the Options tab. 1. In the Chart viewer toolbar, click the Chart To lock the record and field selection in the chart 1. Click the Lock Chart button. When you lock the chart, it only prevents changes to which records and fields are used by the chart. You can continue to modify the chart surround elements and attribute values. Once the chart is unlocked, the chart is automatically updated with the currently selected records and fields. 343

346 To switch from chart type to another 1. Click the arrow next to Chart Type. 2. Click the type that you want to use. For more control over the chart settings, see Defining the data to chart on page 340. To show or hide the chart legend In the Chart dialog box, click the Legend button. For more control over the legend settings, see Designing the chart legend on page 345. To export the chart as a file 1. In the Chart dialog box, click Export Chart. For more information, see Opening the Export Map dialog box on page 407. To zoom in or out of the chart 1. Click the Zoom to Overview button to decrease the magnification so the whole chart appears in the viewer. 2. Click the Zoom Interactive button and drag a rectangle over an area to magnify a specific part of the chart. 3. Click the Zoom In button to increase the magnification by increments and centers the chart in the viewer. 4. Click the Zoom Out button to decrease the magnification by increments and centers the chart in the viewer. To move the magnified chart around with the pointer 1. In the Chart dialog box, click Pan and drag the pointer in the chart viewer. To display the attributes from a chart 1. In the Chart viewer, click the Information button. 2. Click a piece of data in the chart. The clicked data flashes in the viewer and the attributes from that record are displayed under Values on the Information Report dialog box. When used from the Chart toolbar, the Information tool displays all the attributes from the record corresponding to the data clicked in the chart. The Information tool is also used in other places in Focus. For more information, see Using the information report on page 205. To change the color of the a part of the chart or chart surround elements 1. In the Chart viewer, click the Selection Tool button. 2. Click the item in the viewer. 3. On the Chart viewer toolbar, click the arrow next to the Color button. 344

347 4. Click a color from the palette or click More Colors to create a color. To change the look of a part of the chart or a chart surround element 1. Click the Selection Tool button. 2. Click the item in the viewer. 3. Click the arrow next to the Style button. 4. Click the style that you want. Different styles are available depending on the item that you chose. To create a new style, select Style Selector. For more information about the Style Selector, see Selecting a style on page 354. To customize the chart 1. In the Chart dialog box, click the Chart Definition button. For more information, see Defining the data to chart on page 340. To edit or position the chart surround elements 1. Click the Selection Tool button. 2. Click the item in the viewer. 3. Click the Properties button. Designing the chart legend The chart legend is a table listing and describing the representation of the data in the chart. If you deleted the legend from the chart viewer, you can enable it from the Options tab on the Chart Definition dialog box (see Designing the chart surround on page 341 ). To open the Legend Properties dialog box 1. In the Chart viewer toolbar, click the Selection Tool button. 2. Click the legend. 3. In the Chart viewer toolbar, click the Properties button. To design the legend 1. In the Field list (if available), select the field that most clearly describes the records used in the chart. For more information, see About the Category field on page In the Size list, type or select the size of the font used to identify the data in the chart. 3. In the Color list, select the color that you want to use for the font. To modify the color, click More. To change the font, click Selector. For more information about the Selector, see Selecting a style on page Under Placement, click to select the position of the legend in reference to the chart or drag the legend into position. 5. Click OK. Opening the X-axis or Y-axis Properties dialog box 345

348 The labels identify the values along the x-axis and y-axis. 1. In the Chart viewer toolbar, click the Selection Tool button. 2. Click either the axis, the axis heading, or the axis values. 3. In the Chart viewer toolbar, click the Properties button. Customizing the axis heading 1. On the X-axis or Y-axis Properties dialog box, click the Labels tab. 2. In the Axis heading box, type a word or phrase that you want to display along the axis of the chart. 3. In the Size list, type or select the size of the font used for the axis heading. 4. In the Color list, select the color that you want to use for the font. To modify the color, click More. To change the font, click Selector. For more information about the Selector, see Selecting a style on page In the Angle box, type a value between +90 degrees and -90 degrees representing the rotation that you want to apply to the axis heading. In the list select the unit of angular measurement. 6. To keep the characters in the heading parallel to the x-axis, select Keep characters horizontal. 7. Click OK. Customizing the axis tick labels 1. On the X-axis or Y-axis Properties dialog box, click the Labels tab. 2. To display labels for the ticks along the axis, click to select Show Values. 3. In the Field list (if available), select the field that you want to use to identify the ticks on the x-axis. Choose the field that most clearly describes the records used in the chart. For more information, see About the category field on page In the Size list, type or select the size of the font used for the labels. 5. In the Color list, select the color that you want to use for the font. To modify the color, click More. To change the font, click Selector. For more information about the Selector, see Selecting a style on page In the Angle box, type the value representing the counterclockwise rotation that you want to apply to the label. In the list select the unit of angular measurement. 7. Click OK. Opening the X-axis or Y-axis Properties dialog box Dividers are used to mark the axis values. 1. In the Chart viewer toolbar, click the Selection Tool button. 2. Click either the axis, the axis heading, or the axis values.k 3. In the Chart viewer toolbar, click the Properties button. 346

349 Displaying grid lines along the axis 1. On the X-axis or Y-axis Properties dialog box, click the Dividers tab. 2. Select Gridlines. 3. To change the look of the line, select a style in the Style box. If you want to create a style, click Style Selector in the list (see Selecting a style on page 354 ). 4. Click Apply. Displaying ticks 1. On the X-axis or Y-axis Properties dialog box, click the Dividers tab. 2. To display the ticks on the background, select Inside ticks. 3. To display the ticks on the axis but not on the background, select Outside ticks. 4. Click Apply. Opening the Title or Subtitle Properties dialog box You can design and position your title or subtitle in Title or Subtitle Properties dialog boxes or you can modify them directly in the Chart Viewer. As you make changes in the Chart Viewer, Focus updates the Title or Subtitle Properties dialog boxes. 1. In the Chart viewer toolbar, click the Selection Tool button. 2. Click the title or subtitle. 3. In the Chart viewer toolbar, click the Properties button. Customizing the title or subtitle of the chart 1. In the Title box, type a word or phrase that you want as a title or subtitle for your chart. 2. In the Size list, type or select the size of the font. 3. In the Color list, select the color that you want to use for the font. To modify the color, click More. To change the font, click Selector. For more information about the Selector, see Selecting a style on page Under Placement, click to select the position of the title or subtitle in reference to the chart. To place the it manually in the viewer, drag the title or subtitle where you want it. The setting under Placement will automatically change to Custom. 5. Click OK. Opening the data labels properties In the chart, the data is represented by a graphic such as a column or a line. In some cases it may be useful to label the graphic with one or several attribute values from the record. These labels that appear on the data in the chart are called data labels. To display the data labels on the chart, see Designing the chart surround on page

350 1. In the Chart viewer toolbar, click the Selection Tool button. 2. Click a data label. 3. In the Chart viewer toolbar, click the Properties button. Customizing the data labels 1. If you want to include the description from the legend in the label, select the Legend items box. 2. If you want to include the x-axis values in the label, select the X-data values box. 3. If you want to include the y-axis values in the label, select Y-data values box. 4. If you want to display the percent value of the data, select the Percentages box (only available for 100% Stacked Column, 100% Stacked Bar, 100% Stacked Line, 100% Stacked Area, and Pie charts). 5. If you want to draw lines from the percent values to the corresponding data, select Show leader lines (only available for 100% Stacked Column, 100% Stacked Bar, 100% Stacked Line, 100% Stacked Area, and Pie charts). 6. In the Size list, type or select the size of the font used for the labels. 7. In the Color list, select the color that you want to use for the font. To modify the color, click More. To change the font, click Selector. For more information about the Selector, see Selecting a style on page Click OK. Saving a chart Charts are kept in memory as long as the project remains open, even if you close the Chart viewer. You can reopen an existing chart by using the Chart Manager (see Opening or deleting a chart on page 348 ). The settings for each chart that you create while the project is open are saved in the project file (.gpr) when you save the project. The data itself, however, is not saved with the chart. The chart only contains a reference to the data. If you make changes to the layer#s attributes, the chart will reflect the changes in the data the next time you open it, but the design of the chart will remain unchanged. If you close the project without saving it, the charts in memory are discarded along with any other changes in the project file. You can also export your chart as a graphic in one of several file formats. For more information, see Opening the Export Map dialog box on page 407. Opening and deleting a chart The settings for the charts that you create while the project is open are kept in memory as long as the project remains open, even if you close the Chart viewer. By default the charts are listed in the Chart Manager in the order that they were created. When you save the project, only the settings for each chart are saved in the project file (.gpr), not the data itself. The chart only contains a reference to the data. If you make changes to the layer#s attributes, the chart will reflect the changes in the data the next time you open it, 348

351 but the design of the chart will remain unchanged. If you close the project without saving it, the charts in memory are deleted along with any other changes in the project file. To display an existing chart 1. In the main menu of the Attribute Manager (see Performing tasks in the Attribute Manager on page 304 ), click Tools. You can also click Layer in the main menu. 2. Click Charts, and then click Manage. 3. Click the chart that you want to see. 4. Click the View button. 5. Click Close. To sort the list in ascending or descending order 1. In the Chart Manager, click any of the table headings. To delete a chart 1. In the main menu of the Attribute Manager (see Performing tasks in the Attribute Manager on page 304 ), click Tools. or In the Focus main menu, click Layer. 2. Click Charts, and then click Manage. 3. Click the chart that you want to delete. 4. Click the Delete button. 5. Click Close. Digitizing vectors with peripheral devices Focus allows you to connect and use digitizing tablets and GPS tools to create new data. You can use a GPS tool to provide two services within the Focus environment: you can update the position of the cursor within an Area and you can use it as a data input device for a vector layer. In either case, you must have an Area layer that contains the appropriate georeferencing information and you must have a working connection between your computer and your GPS receiver. (See Setting up a GPS receiver on page 111 ) When a digitizing tablet is connected to the computer, you can digitize features from a paper map and use the resulting vector data in your projects. A digitizing tablet consists of a electronic platform (a tablet) and a pointing device (a puck). To set up the tablet to work with Focus, see Setting up a digitizing tablet using Wintab on page 110. Registering a digitizing tablet Once you connect a digitizing tablet to the computer and tape the map to the tablet, you are ready to register a map. Registering the map means that you establish a reference frame between the tablet, the paper map, and 349

352 your project. The reference frame is established by collecting points on the tablet and collecting the same points in the view pane so that Focus can correlate the positions. You can collect the points on each of the four corners of the map or on easily identified features as long as the points are well distributed over the map. With a minimum of four points, Focus can estimate the difference between the coordinates that you entered in the view pane and the coordinates from the tablet. The difference, called an error estimate, reflects the accuracy of the registration between the tablet and Focus. 1. From the Maps tree, click a layer. 2. From the Tools menu, click Digitizing Tablet and then click Register. 3. In the Register Tablet dialog box, click one of the following buttons: Active Area: uses the same georeferencing as the one defined in New Area Active Layer: uses the same georeferencing as one defined in the current layer 4. In the Tie Coordinate Type list box, choose one of the following options: Geocoded: enters the coordinates in georeferenced units Geographic: uses Longitude/Latitude units 5. On the tablet, move the crosshairs of the puck to a feature and press the button to transfer the tablet coordinates to the Tie-Down table. 6. In the Register Tablet dialog box, type the coordinates of the same feature in the Tie Coordinate X and Tie Coordinate Y columns, or you can click to select the feature in the view pane and press Enter to transfer the coordinates to the Tie-Down table. 7. Repeat step 5 and step 6 to complete the registration. If you want to add more points to the table, click the Add button. To remove a point from the table, click the point, and click the Remove button. To remove all the points in the table, click Clear All. 8. Click OK. Importing and exporting tablet registration Once you register the map on the tablet, you can save the registration. The registration remains valid as long as the map is not moved or removed from the tablet. (See Registering a digitizing tablet on page 349 ) To export a registration From the Register Tablet dialog box, click Export. To import a registration From the Register Tablet dialog box, click Import. Using a digitizing tablet Once you register the map on the tablet, you can use the puck to digitize features from the map. (See Registering a 350

353 digitizing tablet on page 349 ) You can assign the puck buttons to perform a variety of actions. (See Assigning text actions and modifiers on page 111 ) You can use the puck with the following tools: Adding points to an active layer on page 303 Selecting a single shape on page 321 Editing vectors using the vector editing tools on page 323 To start digitizing 1. From the Maps tree, click the layer that you want to contain the vectors. 2. From the Tools menu, click Digitizing Tablet and then click Start Digitizing. 3. Click the tool that you want to use or press the puck button assigned to the action that you want to perform. For example, if you want to digitize a line, you can click Line in the New Shapes list on the toolbar or click the puck button that you assigned to NewLine. 4. Use the puck to perform the action that you want. For example, use the puck to digitize a road on the map. To stop digitizing From the Tools menu, click Digitizing Tablet and then click Stop Digitizing. Using the GPS tool Before a GPS tool can be accessed, a connection must be set. A GPS receiver connection is made through the Focus Options dialog box. With a Focus Area open and the GPS receiver connection set, a GPS tool can be used. The GPS tool is launched through the GPS Tool dialog box. 1. Ensure a GPS connection has been established. 2. Open an Area containing appropriate georeferencing information. The Area georeferencing bounds should correspond to the area where a GPS receiver is located. If a GPS receiver is outside of these bounds you cannot update the cursor or collect vectors. In such a case, the vector segment ends and a new segment must be started. 3. From the Tools menu, click GPS Tool. When the GPS tool is active, you can update the view pane cursor position or add vector data to an Area in a project. Inputting vector point data using a GPS receiver 1. Ensure a GPS connection has been established. 2. From the Maps tree, right-click the Area and click New Vector Layer. 351

354 3. In the New Vector Layer dialog box, enable the Point option and click OK. 4. In the Maps tree, select the new point layer. 5. On the Editing toolbar, click the New Shapes arrow and choose Points. 6. From the Tools menu, click GPS Tool. 7. In the GPS Tool dialog box, click one of the following buttons: Capture Stream: updates the new point layer with a point determined by the location of the GPS receiver Capture Point: adds new points to the vector layer at a specified stream interval. You can continue to collect points by repeatedly clicking the button. 8. Click Finish. Inputting vector line or polygon data using the GPS receiver 1. Ensure the GPS Tool dialog box is open. 2. From the Maps tree, right-click the Area layer and click New Vector Layer. 3. In the New Vector Layer dialog box, enable one of the following options in the Layer Type area: Line Topological Line Polygon Topological Polygon 4. Click OK. 5. In the Maps tree, select the new layer. 6. In the GPS Tool dialog box, click one of the following buttons: Capture Stream: adds a new vertex to the vector layer at the specified stream interval. New vertices are added to the line or polygon until you click Finish. Capture Point: adds only the initial vertex to the line or polygon layer. You can continue to collect vertices for the line or polygon with each click of the button. Understanding representation Representation determines the appearance of shapes. Focus applies a default representation to shapes on a vector layer that is not linked to a Representation Style Table (RST). You can continue using the default, create a new RST, or import an existing RST. An RST is a look-up table (LUT) that contains a key and the style associated to that key. The key or the style can also be referred to as a REPCode. The key links the style in the RST to the shape on the layer. Each layer can link to only one RST, but you can link an RST to many layers. Keys can be added as attributes for shapes, such as in the REPCode field, or you can use an existing attribute as the key. When an RST is linked to a layer, Focus identifies the attributes used as keys in the layer and searches for the corresponding keys in the RST. When a match is found, the associated style is applied to the shape in the layer. For example, you can associate an RST to the attributes in a field called roadtype. In the roadtype field, you have a variety of road types such as interstates, highways, and streets. In the RST, the key is the road type with which 352

355 you have styles associated. When a layer is linked to the RST, the shapes are assigned the style according to their key. A style is composed of one or more parts. Each part has a primitive with a priority. Primitives are the building blocks of the style. Each primitive is based on a point, line, or polygon pattern that is designed according to a number of parameters, such as color. The priority determines which part is placed in front of the other parts in the style. You can control the order by assigning the part a priority number. Parts with a higher number appear in front of parts with lower numbered priority. Types of representation style tables Focus uses three types of RSTs: Default, Direct, and Indirect. Default RST: Is controlled by Focus and is applied to vector layers in the absence of any other RST. Direct RSTs: Is also called Embedded Representation, because the style is contained in a layer itself. You can create a Direct RST when you change the appearance of the shapes directly in the view pane using tools in the Display toolbar. Direct RSTs are only available for.pix vector layers. When you change the appearance of shapes in the view pane, Focus creates an RST using the ShapeIds as the keys. The Direct RST is saved directly in a.pix file. Indirect RST: Is a separate file (.rst) that contains an RST. You can link an Indirect RST to one or more layers. In previous versions of Focus, the Indirect RST could also have a.gtd extension. The.gtd file is still compatible and can be edited and resaved as a.gtd file. You can also convert an Indirect RST into a Direct RST by embedding it in the layer through its Properties dialog box. You can build an Indirect RST as System-linked or User-linked. System-linked RST: Is based on an attribute in a layer. To generate the RST, select an attribute from the layer to become the key; Focus creates styles for each key based on the style that you design. Focus automatically links the System-linked RST through the key. User-linked RST: Often called a master RST, is built independently from a layer. To build the RST, you define the keys and manually create styles associated to the keys. Once you build the RST, you link the layers to the RST. The keys in the RST can match an existing attribute in the layer or you can add the keys in a field in the layer. 353

356 Generating an indirect representation style table To generate a System-linked RST, you select an attribute from the layer to become the key, and Focus creates styles for each key, based on the style that you design. Focus automatically links the System-linked RST through the key. 1. From the Maps tree, right-click a layer and click Representation Editor. 2. Choose an attribute that you want associated with a style from the Attribute list box. 3. Click the Generating tab and choose one of the following options from the Method list box Unique Values: assigns a style to each shape according to its value. Each value receives its own style. Ranged Values: assigns a style to all the shapes within a range of numeric values. Each range receives its own style. Choose the type of range that you want to use from the Type list. Shapes containing a NoData value are displayed using the Default RST. Enter a number of ranges by which you want to divide the values in the Number of classes spin box. The minimum and maximum values for the attribute automatically display. If you want to restrict the range available for division, enter a minimum and maximum values in the Min and Max spin boxes. 4. Enable one of the following options: Copy styles from: uses existing styles as the basis for the representation. Choose an RST from the File list box. Generate new styles # creates new styles. Choose a style from the Based on list box. For more information about defining a new style, see Selecting a style on page 354. If you want to assign various colors to the styles, enable the Vary color check box and choose a color scheme. If you want to assign various sizes to the points or lines, enable the Vary size check box. Enter the size in the From and By spin boxes. By default, the units is in millimeters. 5. Click Update Styles. 6. Click OK. Editing the representation styles 1. From the Maps tree, right-click a layer and click Representation Editor. 2. Under the Style column, select a style. 3. Click the Edit Style tab. 4. Make changes to the color and outline width of the style. (See Changing style appearance on page 355 ) 5. Make any changes to the parts of the style. (See Changing style parts on page 355 ) Selecting a style 1. From the Files list in the Style Selector dialog box, select a representation. If a file is not available, click Browse and select a 354

357 file. 2. Click a tab containing the style type that you want. 3. Select a style. 4. Click More. 5. Make any changes to the color and outline width of the style. (See Changing style appearance on page 355 ) 6. Make any changes to the parts of the style. (See Changing style parts on page 355 ) 7. Click OK. Changing style appearance 1. From the Style Selector dialog box, click Simple. 2. Click the Color arrow next to the part you want to change and choose a color from the palette. 3. For the following elements, do the following: Points: enter the factor that you want to use in the Scale box. Scale increases the proportion of the original symbol. Lines: enter a thickness and choose a unit of measurement from the Width list box. Polygons: enter a thickness and choose a unit of measurement from the Outline Width list box. Text: enter a font size and choose a unit of measurement from the Size list box. 4. Click OK. Changing style parts 1. From the Style Selector dialog box, click Advanced. 2. Choose a part that you want to change from the Part list. If you want to add or remove a part, click the Add or Remove button. 3. Enter a number that determines the priority order of the part from the Priority spin box. The highest number appears in front. 4. Choose a type from the Primitive list box. Each Primitive type contains a list of parameters. 5. For each parameter, change any changes to values in the Values column. 6. Click OK. Using an attribute as part of the style An attribute is usually selected from a layer to become the key, and Focus creates styles for each key based on the style that you design. You can, however, use other attributes from a layer to be part of the style for the shapes. To use an attribute as part of the style, you must create a multi-part style (see Editing the representation styles on page 354 ). You assign one of the parts of the style to an attribute through the Advanced Attributes dialog box. 1. Create a multi-part style. 2. From the Style Selector dialog box, choose a part from the Part list box. 3. Choose Vector - Text from the Primitive list box. 4. Set any other parameters. 5. Click OK. 6. In the Representation Editor dialog box, click 355

358 Advanced Attributes. 7. In the Text Attribute list, select a field containing the text that you want to incorporate into the style. 8. Click OK. Opening the Set Style Attribute dialog box 1. Use a Selection tool to select a shape. 2. From the Edit menu, click Set Style Attribute. 3. Click a style. 4. Click OK. Setting the style attribute 1. In the Set Style Attribute box, type the code or name of the style. 2. Click the Find First button. 3. If the result is not the style that you are looking for, click Find Next until you find the style. 4. To limit the styles to a particular type, choose a type in the Graphical Representation list. 5. When the style is selected, click OK. Selecting a symbol 1. From the Symbol Selector dialog box, choose a symbol file from the Files list box. 2. In the gallery, select a symbol. If you want to preview the symbol and the preview window is not displayed, click More. 3. Click OK. Labelling shapes A label is a string of characters placed in close proximity to a shape. You can use labels to display information about the shapes and clarify the subject of the layer. The Label Tool uses an attribute from the layer as a label for the shape. You can create labels for vector, grayscale, and pseudocolor layers that contain attributes. Because the automatic placement of labels may be inadequate, you can make individual changes to the labels by using the Selection Tools in the Editing toolbar. You can change the style of the labels individually using the tools in the Display toolbar. Any changes to the characters used in the label are updated automatically in the view pane and the Attribute table. If you make specific changes to individual labels with the Selection Tools or the Display tools and then use the Label Tool for more changes, specific changes may be replaced by the options set in the Label Tool. 1. From the Maps tree, right-click a layer and click Properties. 2. In the Properties dialog box, click the Labels tab. 3. See Managing the labels on page 356. Managing the labels The Label tab on the layer#s Properties dialog box contains the label sets associated with that layer. For more information about labels see Labelling Shapes on 356

359 page 356 and Managing data properties on page 35. If you are making modifications to individual labels with the intention of printing a map, switch Focus to Map View mode before beginning your edits. To switch to Map View mode, in the main menu click View and then Map View Mode. 1. To display the labels in the View Pane, click in the Visible column beside the label set that you want to show. To hide the labels, click to clear the check mark. 2. To make the labels selectable in the View Pane, click in the Selectable column beside the label set that you want. 3. To add a new label set, click Add New. For more information, see Adding labels to a layer on page To modify existing labels, click Modify. For more information, see Changing labels on page To remove a label set, select the layer under Label Name and click Delete. 6. Click OK. Adding labels to a layer 1. From the Properties dialog box, click the Label tab and click Add New. 2. Set options for the labels. (See Defining the design and layout for labels on page 358 ) 3. Design the look for the labels. (See Setting label representation on page 357 ) 4. Click OK. Setting label representation Representation controls the appearance of all labels on a layer. 1. From the Label Tool dialog box, click the Style button and create a style for the text (see Selecting a style on page 354 ). 2. In the Color box, you can change the color of the font that you selected in the Style Selector. 3. In the Size box, you can change the size of the font and select the unit of measure that you want. 4. Click OK. Changing labels If you are making modifications to individual labels with the intention of printing a map, switch the Focus view pane to Map View mode by clicking the Map View Mode button before begining your edits. 1. From the Maps tree, right-click a layer and click Properties. 2. From the Properties dialog box, click the Labels tab. 3. Select the label you want to change and click Modify. If you want to change the representation for the labels, see Setting label representation on page 357. If you want to change the options for the labels, see Defining the design and layout for labels on page

360 . 4. Click OK. Defining the design and layout for labels The Label Tool provides the general look and layout for labels. It also follows some of the formatting options determined for the field in the Attribute Manager. For example, if the field in the attribute table used for the labels is defined as having two decimal places, the labels will have two decimal places. You can make individual changes to the labels by using the Selection Tools in the Editing toolbar. You can change the style of the labels individually using the tools in the Display toolbar. If you are making modifications to individual labels with the intention of printing a map, switch the focus view pane to Map View mode by clicking the Map View Mode button before begining your edits. The layer type determines which options are available for labels. For example, an unstructured layer can contain points, lines, and polygons, and all options are available. See also: Defining which attribute to use for the label on page 358 Setting the position for point layer labels on page 359 Setting the position for line layer labels on page 359 Setting the position for polygon and raster layer labels on page 360 Defining which attribute to use for the label 1. From the Label Tool dialog box, click the General tab. 2. Choose an attribute from the Attribute list box. 3. Type a name for the labels in the Label set name box. 4. To label only the shapes that you have selected in the layer, select Label selected shapes only. Clear the check mark to label all the shapes in the layer. 5. To clear existing labels and relabel the shapes in the layer, select Overwrite existing labels. Clear the check mark to label only the unlabelled shapes. If you selected Label selected shapes only in the previous step, only the shapes that you have selected are relabeled. 6. To display #NoData# as a label for records containing null values or lacking data, select Include NoData. Clear the check mark to hide the NoData labels. 7. Click OK. See also Setting label representation on page

361 Setting the position for point layer labels on page 359 Setting the position for line layer labels on page 359 Setting the position for polygon and raster layer labels on page 360 Setting the position for point layer labels The Offset determines the location of the label's anchor relative to the point, not the alignment of the label's text relative to the label's anchor. To change the alignment of the text, change its style (see Setting label representation on page 357 ). 1. In the Label Tool dialog box, click the Point Options tab. 2. In the Vertical list, type or select the value representing the vertical position of the label relative to the point. In the list, select the measurement unit. 3. In the Horizontal list, type or select the value representing the horizontal position of the label relative to the point. 4. Select Keep equal to keep the vertical and horizontal offset the same distance. Clear the check mark to keep the offsets independent of each other. See also Setting label representation on page 357 Defining which attribute to use for the label on page 358 Setting the position for line layer labels on page 359 Setting the position for polygon and raster layer labels on page 360 Setting the position for line layer labels The Position and Offset determine the location of the label's anchor relative to the line, not the alignment of the label's text relative to the label's anchor. To change the alignment of the text, change its style (see Setting label representation on page 357 ). 1. In the Label Tool dialog box, click the Line Options tab. 2. Under Vertical in the Position list, select whether you want the label to appear above or below the line. 3. In the Offset list, type or select the value representing the space between the line and the label. In the list, select the measurement unit. 4. Under Horizontal in the Position list, select whether you want the label to appear to the left, right, or in the middle of the line. 5. In the Offset list, type or select a value to adjust the position of the label. In the list, select the measurement unit. See also Setting label representation on page

362 Defining which attribute to use for the label on page 358 Setting the position for point layer labels on page 359 Setting the position for polygon and raster layer labels on page 360 Setting the position for polygon and raster layer labels The Offset determines the location of the label's anchor relative to the centroid, not the alignment of the label's text relative to the label's anchor. To change the alignment of the text, change its style (see Setting label representation on page 357 ). 1. In the Label Tool dialog box, click the Area Options tab. 2. In the Vertical list, type or select the value representing the vertical offset of the label relative to the centroid of the area. In the list, select the measurement unit. 3. In the Horizontal list, type or select the value representing the horizontal offset of the label relative to the centroid of the area. 4. Select Keep equal to keep the vertical and horizontal offset the same distance. Clear the check mark to keep the offsets independent of each other. See also: Setting label representation on page 357 Defining which attribute to use for the label on page 358 Setting the position for point layer labels on page 359 Setting the position for line layer labels on page 359 Designing a symbol The Symbol Editor contains tools to create or edit symbols. A symbol is composed of one or more parts. A symbol can be a single design or a compilation of overlapping designs and are stored in files with a.sym extension. Symbol files can be used in one or more RSTs. See also: Understanding the symbol working area on page 360 Creating a symbol on page 361 Creating a multi-part symbol on page 361 Selecting a symbol from the symbol file on page 362 Setting symbol representation on page 362 Editing the symbol RST on page 362 Understanding the symbol working area 360

363 The working area of the Symbol Editor equals four units square in the map. If you draw a symbol that occupies the whole working area, it will be two units high on the map. The bounding box is the blue box that appears inside the working area. This box is one unit square on the map. The measurement unit is defined in the RST Properties dialog box. Creating a symbol 1. From the Maps tree, right-click a layer and click Representation Editor. 2. In the tree, right-click Symbol Files and click NewSymbol. 3. Double-click NewSymbol.sym. 4. In Symbol Editor, click Symbol and then click Create Symbol. 5. In the Attributes dialog box, type a number that will represent the symbol in the New box below Current SymbolId. 6. Type a label for the symbol in the New box below Description. 7. Click OK. 8. Draw a symbol. Use the tools explained in Adding points to an active layer on page 303, Selecting a single shape on page 321, and Editing vectors using the vector editing tools on page From the File menu, click Save Symbol. Creating a multi-part symbol If you want your symbol to contain different colors, you must divide your design into parts. Each part of the symbol contains the design elements of one color. You can use the Symbol Editor to determine the form and structure of the symbol, but the parameters of the symbol, such as color and scale, are determined in the Representation Editor. (See Editing the representation styles on page 354 ) You can rename and save a symbol file to a new location with the symbol file Save As dialog box. To open the symbol file Save As dialog box, right-click a symbol layer in the Maps tree and click Save As. (See About the symbol file Save As dialog box on page 362 ) 1. Create a design. (See Designing a symbol on page 360 ) 2. From the Symbol menu in the Symbol Editor, click Duplicate Symbol. 3. In the Attributes dialog box, type a number that will represent the symbol in the New box below Current SymbolId. 4. Type a label for the symbol in the New box below Description. 5. Click OK. 6. Keep the shapes that you want and use the Selection tools to delete all the other shapes that are destined for another color. 7. Change the style of the remaining shapes. (See Setting symbol representation on page 362 ) 8. Select the source symbol (See Selecting a symbol from the symbol file on page 362 ) and repeat for each part of the symbol. 9. From the File menu, click Save Symbol. 361

364 Selecting a symbol from the symbol file The Select Symbol dialog box lists all the symbols in the symbol file. You can select individual symbols from the symbol file. 1. From the Symbol menu in the Symbol Editor, click Select Symbol. 2. Click a symbol. 3. Click OK. Setting symbol representation 1. Use a Selection tool to select a shape. 2. From the Edit menu in the Symbol Editor, click Set Style Attribute. 3. Click a style. 4. Click OK. Editing the symbol RST The Symbol RST controls the width of the lines, the size of the text, and the font. From the Tools menu in the Symbol Editor, click Edit RST. If you want to change a style, select it and make any modifications. About the symbol file Save As dialog box The symbol file Save As panel lets you rename and save a symbol file in the Maps tree to a new location. Input The Input area shows the name and location of the current symbol file. Symbols: Reports the name and location of a symbol file. Output Lets you choose a different symbol file, select a format for the output, and rename a symbol file. File: Lets you choose a symbol file from the current data. Browse: Opens a File Selector dialog box, where you can select a different location for the output. Format: Lets you select a format for your output. 362

365 Description: Lets you enter a new name for the output symbol file. 363

366 364

367 Chapter 9 Saving a project file When you prepare data for a publication, it is recommended that you organize the information in a Focus project file. (See Working with project files on page 31 ) From the File menu, click Save Project. Renaming a map 1. In the Maps tree, right-click a map and click Rename. 2. Type a name for the map and press Enter. Starting a new map Focus must be in Map View mode in order to work on Map projects. By default, when you open data files, Focus is in Area View mode. 1. From the View menu, click Map View Mode. 2. In the Maps tree, click a map element to select and change it. If you want to open the Properties dialog box for a selected item, double-click it in the Maps tree. You can create a Map by either clicking the New Map button on the Maps toolbar or by right-clicking the area under the Maps tree and clicking New Map. When you create a new Map, Focus automatically places an empty frame in the view pane that represents the paper on which the Map is printed. Maps have several properties that you can change with the Map Properties dialog box. Working with map properties From the Maps tree, right-click a map and click Properties. You can change the Map description by typing in the Name box. When you click Apply, the text appears in the Maps tree as the Map name. You can name Maps, Areas, and layers the same way you would rename a file in other Windows applications. Click the file name in the Maps tree and type a name for the Map or layer. You can also right-click a file name, and click Rename. Changing the paper size by dragging a resize handle 365

368 By default, new Maps have a paper size of x millimetres (8.5 x 11 inches). You can change the paper size to several standard sizes in the Map Properties dialog box. You can also set a custom paper size by dragging the Map handles in the view pane. 1. On the ViewMap toolbar, click the Map View button. 2. In the Maps tree, select a Map. 3. In the view pane, drag a resize handle. Drag a map handle in the view pane to resize a map sheet. Changing the paper size from the Map Properties dialog box 1. Double-click a Map. 2. In the Map Properties dialog box, click the Page Setup tab. 3. Enable an orientation option. 4. Select a standard paper size from the Page Size list box. If you want to use a custom paper size, choose Custom and enter the dimensions in the Width and Height spin boxes. Choose a unit of measurement from the list box. 5. Click OK. Working with areas Areas hold the file boundaries for image (raster) and vector layers. They can contain several layers for the same geographical region, and you can have as many Areas in a project as you want. Each Area has a unique georeferencing system. When you add a layer, it is automatically georeferenced and scaled to the Area. You can add an Area to a Map and place layers within it. The new layers hold vector and raster data, such as polygons, points, and segments that you need for the Map. Surrounds and indices are held in similar areas, but you can work with these elements independently. (See Working with surrounds on page 371 ) You can adjust the bounds of an Area independently from a Map. When you add an Area, files are shown below the Map in the Maps tree. Vector and raster layers contained within the Area are shown below it. If you resize or move an Area so that part of it lies outside the extents of the Map (paper), the Area appears red in the Maps tree. From the Maps tree, right-click a Map and click New Area. 366

369 Scaling an area In cartography, scale is the ratio of the distance between two points on a Map, and the actual distance between the same two points on the Earth#s surface. Scales can be represented as a Ratio or representative fraction (RF), such as 1:50,000 or 1/50,000, which means that one unit of measurement on the Map equals 50,000 of the same units on the Earth's surface. Graphic scale, usually a straight line on which distances (most often in kilometers or miles) have been marked off. Scale statement, such as 1 cm = 100 km. This scale statement means one centimetre on the Map represents 100 kilometers on the Earth's surface. New Areas are automatically scaled to the best fit for the dimensions of a Map. For example, Focus sets the area scale for a standard 8.5 x 11 page to a scale factor of 1:20000 by default. A new Area contains no raster or vector data. When you add new data, Focus automatically scales it to the area scale. When Focus is in Map mode, you can click on an area in the Maps tree. you can modify the area in the view pane by dragging one of the eight handles in the viewer. Note: With an area, the middle handles crop the image. The corner handles rescale it. Use the area handles in the view pane to rescale, crop, or enlarge an Area. 1. From the Maps tree, double-click an Area. 2. In the Area Properties dialog box, click the General tab. 3. Choose a scale from the Scale list box. If you want to create a different scale, choose Custom and enter a value in the Scale box. 4. Click OK. When you change the scale in the Area or Math Model Area Properties dialog boxes, it becomes the scale for all new layers added to that Area. Rescaling an area When you rescale data in the view pane, you extend or compress both the horizontal and vertical planes of the data. The aspect ratio stays the same. All features in a selected Area are enlarged or reduced by a factor corresponding to the ratio of rescaling. You can change the Scale Factor. 367

370 You can perform rescaling operations in both Map or Area view mode. 1. Ensure Focus is in Map view mode. 2. In in the Maps tree, select an Area. 3. Drag a corner of the Area to a new position. georeferencing information. Understanding Areas Note: Surround areas can be resized and rescaled. However, scale bars and neatline will not be affected by rescaling. The paper range and the scale factor are adjusted automatically when you rescale a selected area, but the georeferenced information remains the same. To view the new scale values, open the Area Properties dialog box. The paper range and the geographic range are adjusted automatically when you resize a selected area but the appearance of the existing layers does not change. Setting area properties An Area is a rectangular frame that holds layers of data and serves as a window into a location on the Earth. Its properties determine how the layers of data are displayed. The features available on the Layout tab on the Area Properties dialog box determine the position of the Area on the Map. The Map represents the sheet of paper on which the project is printed. You can have several Areas on a Map and each Area retains its own projection and From the Maps tree, right-click a New Area and click Properties. Setting area properties 1. From the Area Properties dialog box, click the General tab. 368

371 2. Type a name for the Area in the Name box. If you want to have a border around the Area, enable the Show Outline check box. 3. Choose a scale to determine the ratio of the distance between two points from the Scale list box. If you want to use a custom scale, choose Custom and type the ratio value. (See also Scaling an area on page 367 ) 4. Click the Layout tab. 5. Enter a value used to rescale the representation displayed on the Map in the Scale Factor spin box. For example, if the symbol is 1 millimeter wide, a scale factor of 5 will display the symbol as 5 millimeters wide on the Map. 6. Enter a value representing the priority of the Area relative to other Areas in the Priority spin box. Areas with higher priority levels (larger numbers) mask overlapping Areas with lower priorities. (See Changing the layer priority on page 28 ) 7. In the Position area, enter a value representing the horizontal distance from the left edge of the Map in the Left spin box and choose a unit of measurement for the position and size. 8. Enter a value representing the vertical distance from the bottom edge of the Map in the Bottom box. 9. In the Size area, enter a value for the Area as it appears on the Map in the Width and Height spin boxes. If you want to automatically adjust the extents of the Area to accommodate the data, enable the Automatic Resize check box. 10. Click the Projection/Extents tab. 11. Enable one of the following options in the Bounds list box: Geocoded: displays the bounds in georeferenced units Geographic: displays Longitude/Latitude units 12. Enter the coordinates of the upper-left corner and lower-right corner of the Area in the appropriate boxes. 13. Enter a value for an angle of rotation in the Rotation box and choose a unit of measurement. If you want to limit processes to a subset of the data, click Define Clip Region. Enable the Enable check box to activate the clip region. 14. Click OK. Opening the Math Model Area Properties dialog box A Math Model Area is similar to an Area, except the projection is determined by a math model segment contained in the image file. A Math Model Area is a rectangular frame that holds a layer containing a raw image displayed without correction, but accurate ground coordinates are calculated for each pixel using the pixel and line coordinates, the math model, and the digital elevation model (DEM) or an approximate elevation value that you provide. For more information, see Using a math model with images on page 40. You cannot open other images in a Math Model Area, 369

372 because the math model is computed for a specific image. You can, however, add geocoded vector layers to the Math Model Area. Due to the special nature of a Math Model Area, surround elements, such as grids and north arrows are disabled, and the extents are determined by the file. From the Maps tree, right-click a Math Model Area and click Properties. Setting Math Model Area properties A Math Model Area is similar to an Area, except the projection is determined by a math model segment contained in the image file. A Math Model Area is a rectangular frame that holds a layer containing a raw image displayed without correction, but accurate ground coordinates are calculated for each pixel using the pixel and line coordinates, the math model, and the digital elevation model (DEM) or an approximate elevation value that you provide. For more information, see Using a math model with images on page From the Math Model Area Properties dialog box, click the General tab. 2. Type a name for the Math Model Area in the Name box. If you want to have a border around the Math Model Area, enable the Show Outline check box. 3. Choose a scale to determine the ratio of the distance between two points in the Math Model Area from the Scale list box. If you want to use a custom scale, choose Custom and type a value ratio. (See also Scaling an area on page 367 ) 4. Click the Layout tab. 5. Enter a value used to rescale the representation displayed on the Map in the Scale Factor spin box. For example, if the symbol is 1 millimeter wide, a scale factor of 5 will display the symbol as 5 millimeters wide on the Map. 6. Enter a value representing the priority of the Math Model Area relative to other Areas in the Priority spin box. Areas with higher priority levels (larger numbers) mask overlapping Areas with lower priorities. (See Changing the layer priority on page 28 ) 7. In the Position area, enter a value representing the horizontal distance from the left edge of the Map in the Left spin box and choose a unit of measurement for the position and size. 8. Enter a value representing the vertical distance from the bottom edge of the Map in the Bottom box. 9. Click the Projection/Extents tab. 10. Enable one of the following options in the Bounds list box: Geocoded: displays the bounds in georeferenced units Geographic: displays Longitude/Latitude units If you want to limit processes to a subset of the data, click Define Clip Region. Enable the Enable 370

373 check box to activate the clip region. 11. Click OK. Working with surrounds A surround is a collection of graphical elements that gives meaning or clarifies the meaning of geographical information displayed in a Map. It puts the data into context that can be analysed, organized, and communicated effectively. Focus provides the following surround elements: Neatline: a visible or invisible line marking the boundary around the Area beyond which no data is displayed. Border: a decorative frame around the Area. It is drawn behind the Area and can be used as a background. Grid: a pattern of regularly-spaced lines, usually used to indicate coordinates or used as dividers. Legend: a table listing and describing the symbols and elements in the Area. Picture: a graphic such as an image or logo that you place on a Map. North Arrow: a graphic used to indicate the direction of True North, Magnetic North, or Grid North in relation to an Area. Scale bar: a graphical representation of the ratio between a distance in the Area and the actual distance on the ground. Title: a name or phrase given to identify the Area. Paragraph: a block of text, such as an explanatory paragraph, that is placed on the Map. Surround elements are positioned relative to the neatline of the Area. If an Area does not contain a neatline, the positioning is based on the Area extents. Any surround element, except for the neatline, can appear more than once in an Area. For example, if you want to show two different scales in your map, such as one in kilometers and the other in miles, you can create two scale bars. You can modify the look of the surround elements and save those settings as a Quick Style, which can be applied to the same type of surround element in the project. For more information, see Selecting an existing quick style on page 397. Creating a surround The surround elements are displayed in the Maps tree for the Area to which they are associated. If you place a surround element so that part of it lies outside the boundaries of the Map, it appears red in the Maps tree. For more information about surrounds, see Working with surrounds on page From the View menu, click Map View Mode. 2. In the Maps tree, right-click an Area and click Surround. 3. In the Surround dialog box, click a box next to any element you want to use in the Map. A check mark next to an element indicates it is selected. 4. Choose a style for a selected element from the Select a QuickStyle list. 371

374 If you want to create a new style, click Properties and follow Creating a custom quick style on page Click OK. Setting a default surround element 1. From the Surround dialog box, click a box next to any element you want to use in the Map. A check mark next to an element indicates it is selected. 2. Click Preferred surround. Setting a default quick style 1. From the Surround dialog box, click a box next to any element you want to use in the Map. A check mark next to an element indicates it is selected. 2. Choose a style for a selected element from the Select a QuickStyle list. 3. Click Set as Default. Setting surround element properties You can change the look and position of a surround element through the Properties dialog box. From the Maps tree, right-click a surround element and click Properties. About neatlines A neatline is a line around an Area that separates data from the rest of the surround. It is a line marking the boundary around the Area beyond which no data is displayed. Unlike the other surround elements, the neatline can only be used once in each Area. The neatline also serves as the frame of reference for positioning other surround elements. To add a neatline to an Area, see Creating a surround on page 371. To open the Neatline Properties dialog box, see Setting surround element properties on page 372. The look of a neatline is determined by its: General properties (see Setting the position of a neatline in relation to an area on page 372 ) Position (see Setting the updating behavior on page 395 ) Quick Style (see Selecting an existing quick style on page 397 ) Setting the position of a neatline in relation to an area A neatline separates data from the rest of the surround. For more information, see About neatlines on page 372. You can set the position of the neatline in relation to the boundary of the Area or according to specific measurements. 372

375 1. From the Maps tree, right-click a neatline and click Properties. 2. In the Neatline Properties dialog box, click the General tab. 3. Click the Style button and create a style for the line (see Selecting a style on page 354 ). 4. In the Distance From Area area, enter a value representing the distance from the left neatline to the Area in the Left spin box and choose a unit of measurement from the list box. If you want to keep the distance between the neatline and the Area the same on all sides, enable the Keep equal check box and go to step Enter a value representing the distance from the right neatline to the Area in the Right spin box. 6. Enter a value representing the distance from the top neatline to the Area in the Top spin box. 7. Enter a value representing the distance from the bottom neatline to the Area in the Bottom spin box. 8. Click OK. Setting specific extents for a neatline Instead of using the extents of an Area as the basis of a neatline position, you can define specific coordinates. The X values are measured from left side of the Map (paper) and the Y values are measured from the bottom of the Map. 1. In the Neatline Properties window, click Advanced (see Setting specific extents for a neatline on page 373 ). 2. In the Neatline Advanced Properties dialog box, enable one of the following options: Paper: bases extents on paper measurements Georeferenced: bases extents on a geographic coordinate system 3. Enter a value measured from the left edge of the Map to the lower left corner of the neatline in the X min spin box and choose a unit of measurement from the list box. 4. Enter a value measured from the left edge of the Map to the lower right corner of the neatline in the X max spin box. 5. Enter a value measured from the bottom edge of the Map to the lower left corner of the neatline in the Y min spin box. 6. Enter a value measured from the bottom edge of the Map to the upper left corner of the neatline in the Y max spin box. 7. Click OK. About borders A border is a decorative frame that surrounds a Map. You can build a border as simple or as complex as you want. To add a border to an area, see Creating a surround on page 371. To open the Border Properties dialog box, see Setting surround element properties on page 372. The look of a border is determined by its: General properties (see Changing border style and proximity to neatline on page 374 ) Position (see Setting the updating behavior on page 395 ) Quick Style (see Selecting an existing quick style on page 397 ) 373

376 Changing border style and proximity to neatline A border is a decorative frame around a Map. For more information, see About borders on page 373. The position of a border is based on the position of a neatline or on the Area if the neatline is not set. 1. From the Maps tree, right-click a border and click Properties. 2. In the Border Properties dialog box, click the General tab. 3. Click the Style button and create a style for the border (see Selecting a style on page 354 ). 4. In the Distance To Neatline area, enter a value representing the distance from the left border to the left neatline (or Area) in the Left spin box and choose a unit of measurement from the list box. If you want to keep the distance between the border and the neatline (or Area) the same on all sides, enable the Keep equal check box and go to step Enter a value representing the distance from the right border to the neatline (or Area) in the Right spin box. 6. Enter a value representing the distance from the top border to the neatline (or Area) in the Top spin box. 7. Enter a value representing the distance from the bottom border to the neatline (or Area) in the Bottom spin box. 8. Click OK. A grid is an array of regularly-spaced parallel and perpendicular lines arranged over an Area. Each cell is used as a reference point for determining locations or coordinates. For example, they can be used in conjunction with street indexes. A grid A graticule is drawn along latitude and longitude lines or a representation that relates points in an Area to locations on the ground. A georeferenced graticule About grids 374

377 Georeferenced grids are linked to Area data. They can be used to locate and reference Map features with the Earth through georeferenced coordinate systems. Georeferenced grids are not always rectilinear. For example, latitude/longitude grids have curved grid lines, while UTM grids have both curved and straight lines. The position of a grid is based on the position of a neatline or on an Area if a neatline is not set. To add a grid to an area, see Creating a surround on page 371. You cannot create a grid in a rotated Area (Raster Up). For more information, see About rotated rasters on page 34. To open the Grid Properties dialog box, see Setting surround element properties on page 372. The look of a grid (or graticule) is determined by its: General properties (see Changing grid pacing and proximity to neatline on page 375 ) Layout properties (see Changing the style and layout of the grid on page 376 ) Headings properties (see Changing the location and style of the grid headings on page 377 ) Label properties (see Changing the location and style of the grid labels on page 377 ) Position (see Setting the updating behavior on page 395 ) Quick Style (see Selecting an existing quick style on page 397 ) Changing grid pacing and proximity to neatline The position of a grid is based on the position of the neatline or on an Area if the neatline is not set. 1. From the Maps tree, right-click a grid and click Properties. 2. In the Grid Properties dialog box, click the General tab. 3. In the Distance To Neatline area, enter a value representing the distance from the left border to the left neatline (or Area) in the Left spin box and choose a unit of measurement from the list box. If you want to keep the distance between the border and the neatline (or Area) the same on all sides, enable the Keep equal check box and go to step Enter a value representing the distance from the right border to the neatline (or Area) in the Right spin box. 5. Enter a value representing the distance from the top border to the neatline (or Area) in the Top spin box. 6. Enter a value representing the distance from the bottom border to the neatline (or Area) in the Bottom spin box. 7. Enable one of the following options: Fixed Interval: sets the grid spacing according to a fixed distance between the lines. Follow step 8 to step 10. Fixed count: sets grid line spacing according to a fixed number of lines. Follow step 11 and step In the Fixed Interval area, enable one of the 375

378 following options: Paper: bases a grid on paper measurements Georeferenced: bases a grid on an Area projection Latitude/Longitude: bases a grid on latitude and longitude coordinates 9. Enter a value representing the horizontal width of the column in the Column Width spin box and choose a unit of measurement from the list box. 10. Enter a value representing the vertical width of the row in the Row Height spin box. If you want to keep the column width and row height the same size, enable the Keep equal check box. See also Changing the style and layout of the grid on page 376 Changing the location and style of the grid headings on page 377 Changing the location and style of the grid labels on page 377 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Changing the style and layout of the grid 11. In the Fixed Interval area, enter a value representing the number of columns that you want to cover the Area in the Column spin box. 12. Enter a value representing the number of rows that you want to cover the Area in the Row spin box. If you want to keep the number of columns and rows the same, enable the Keep equal check box. 13. Click OK. You can change the look of a grid. 1. In the Grid Properties dialog box, click the Layout tab. 2. In the Border area, enable the Show border check box and click the Style button. 3. Create a style for the line (see Selecting a style on page 354 ). 4. In the Display area, enable one of the following options: Lines: forms the grid using solid lines Crosses: displays only parts of the grid where the lines intersect. Enter a value representing the measurement for the crosses in the Size spin box and choose a unit of measurement. None: hides the grid lines 5. Click the Style button and create a style for the 376

379 lines or crosses (see Selecting a style on page 354 ). 6. Click OK. See also Changing grid pacing and proximity to neatline on page 375 Changing the location and style of the grid headings on page 377 Changing the location and style of the grid labels on page 377 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Changing the location and style of the grid headings Headings are numbers or letters (or both) positioned on the edges of the grid that identify the lines or sections on the grid. 1. In the Grid Properties dialog box, click the Headings tab. 2. In the Location and Appearance area, enable any of the check boxes to indicate where you want the headings to appear. 3. Click the Style button and create a style for the text (see Selecting a style on page 354 ). 4. Enter a measurement representing the space that you want between the grid border and the headings in the Distance from grid spin box. 5. In the Type area, enable one of the following options: Geo style: aligns the headings with the grid lines.choose a format representing how you want the headings to appear in the Format list box. Paper style: center the headings between the grid lines. Choose an alphabetic or numeric format from the Rows and Columns list boxes. By default, headings are ordered from the top down and from left to right. If you want to reverse the order, enable the Reverse check box for the row or column, or both. 6. Click OK. See also Changing grid pacing and proximity to neatline on page 375 Changing the style and layout of the grid on page 376 Changing the location and style of the grid labels on page 377 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Changing the location and style of the 377

380 grid labels Labels are the numbers positioned on the grid lines that show the Northings and Eastings for a grid. You can change the look of the numbers and adjust the position of Northings and Eastings relative to the grid lines. 1. In the Grid Properties dialog box, click the Label tab. 2. In the Easting Placement area, enable any of the check boxes to indicate where you want the label to be positioned in reference to the lines on the X-axis. UR represents upper right, UL represents upper left, LR represents lower right, and LL represents lower left. 3. Enter a value representing the space between the label and the Y-axis as the label moves along the X-axis in the Horizontal Offset spin box. 5. In the Northing Placement area, enable any of the check boxes to indicate where you want the label to be positioned in reference to the lines on the Y-axis. UR represents upper right, UL represents upper left, LR represents lower right, and LL represents lower left. 6. Enter a value representing the space between the label and the Y-axis as the label moves along the X-axis in the Horizontal Offset spin box. If you want to have both the horizontal offset and vertical offset the same distance from the lines, enable the Keep equal check box and skip step Enter a value representing the space between the label and the X-axis as the label moves along the Y-axis in the Vertical Offset spin box. If you want to have both the horizontal offset and vertical offset the same distance from the lines, enable the Keep equal check box and skip step Enter a value representing the space between the label and the X-axis as the label moves along the Y-axis in the Vertical Offset spin box. 8. In the Appearance area, click the Style button and create a left-aligned style for the text (see Selecting a style on page 354 ). 9. Choose a format that represents how you want the labels to appear from the Format list box. 10. Click OK. See also Changing grid pacing and proximity to neatline on page 378

381 375 Changing the style and layout of the grid on page 376 Changing the location and style of the grid headings on page 377 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 About legends A legend is a list of colors, symbols, and patterns displayed in an Area with a description or label explaining what each means. Each color, symbol, and pattern is represented in the legend by a small sample or example of itself. The legend is anchored to the neatline or to an Area if a neatline is not set and is positioned in reference to that anchor. Example of a legend To add a legend to an Area, see Creating a surround on page 371. To open the Legend Properties dialog box, see Setting surround element properties on page 372. The look of a legend is determined by its: 379

382 General properties (see Setting the number of columns and designing a border for a legend on page 380 ) Title properties (see Adding a title to the legend on page 380 ) Filter properties (see Adding styles to a legend on page 381 ) Structure properties (see Organizing sections in a legend on page 382 andcreating a design for sections in a legend on page 383 ) Columns properties (see Organizing legend columns on page 384 ) Position (see Setting the updating behavior on page 395 ) Quick Style (see Selecting an existing quick style on page 397 ) Setting the number of columns and designing a border for a legend The General properties of a legend control the number of columns into which it is divided, the alignment of the columns, and the style of the borders. 1. From the Maps tree, right-click a legend and click Properties. 2. In the Legend Properties dialog box, the General tab. 3. In the Columns area, enter a value for the number of columns that you want in the Number of columns box. 4. Enable one of the following Column alignment options: Top: aligns the columns along their top edges Bottom: aligns the columns along their bottom edges 5. In the Borders area, enable any of the following check boxes: Show legend border: creates a border around the legend. Click the Style button and create a style (See Selecting a style on page 354 ). Show sample border: draws an outline around each sample in the legend. Click the Style button and create a style (see Selecting a style on page 354 ). 6. Click OK. See also Adding a title to the legend on page 380 Adding styles to a legend on page 381 Organizing sections in a legend on page 382 Creating a design for sections in a legend on page 383 Organizing legend columns on page 384 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Adding a title to the legend A title is the main heading for a legend. It identifies the 380

383 information included in the legend. Subtitles inside a legend are controlled on the Structure tab (See Organizing sections in a legend on page 382 ). 1. In the Legend Properties dialog box, click the Title tab. 2. Enable the Show title check box. 3. Type the legend title in the Title box. 4. Click the Style button and create a style (see Selecting a style on page 354 ). 5. Enable one of the following Title placement options: Top: places the title at the top of the legend Bottom: places the title at the bottom of the legend 6. Enter a value representing the distance between the title and the legend in the Spacing from columns spin box and choose a unit of measurement from the list box. 7. Enable one of the following Alignment options: Left: aligns the title along the left edge of the legend Center: centers the title over or under the legend Right: aligns the title along the right edge of the legend 8. Click OK. See also Setting the number of columns and designing a border for a legend on page 380 Adding styles to a legend on page 381 Organizing sections in a legend on page 382 Creating a design for sections in a legend on page 383 Organizing legend columns on page 384 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Adding styles to a legend You can make a first draft of the legend in a filter table. The table contains all layers in an Area. You can select layer styles or whether you want the legend to contain all the styles in the Representation Style Table (RST) linked to the selected layers or only the styles that are used in the Area. Once you have made an initial selection, you can refine the legend. Cells that appear gray under the All Repcode column in the filter table indicate the layer is not associated to an indirect RST and cannot be used in the legend. For more information about RSTs, see Understanding representation on page 352. If a style in the RST contains a text attribute, you can include it in the legend. The style associated to a text attribute is represented in the legend by a capital letter T in the corresponding style. For more information about text attributes, see Using an attribute as part of the style on page

384 1. In the Legend Properties dialog box, click the Filter tab. 2. Click a layer in the Generate column. A check mark indicates a layer is included in the legend. 3. Click a layer in the All Repcode column that you want in the legend. A check mark indicates a layer is included in the legend. If you want to include styles associated to the text attributes in the legend, enable the Add text to RST hierarchy check box. 4. Click OK. See also Organizing sections in a legend You can refine a legend and design its look. The RST hierarchy list contains all RSTs associated with layers, even those not uses in the Area. Items listed in the Legend hierarchy box appear in the legend. You can group items under sections and subsections to make the information more easily found in an Area. In the following figure, the items are separated in two sections: Transportation and Sports Facilities. The Sports Facilities section is divided into two subsections, making it easier to find the Indoor Pool. Example of the organization of a legend Setting the number of columns and designing a border for a legend on page 380 Adding a title to the legend on page 380 Organizing sections in a legend on page 382 Creating a design for sections in a legend on page 383 Organizing legend columns on page 384 Setting the updating behavior on page 395 Selecting an existing quick style on page

385 To add sections 1. In the Legend Properties dialog box, click the Structure tab. 2. In the Legend hierarchy list, select the section under which you want to add a subsection. 3. Click the Add button. To remove sections 1. In the Legend Properties dialog box, click the Structure tab. 2. In the Legend hierarchy list, select a section. 3. Click the Remove button. To move an item to a section Drag an item to a section. To add an item from an RST to a legend 1. In the Legend hierarchy list, select a section. 2. In the RST hierarchy box, select an item. 3. Click the button between the lists. For more information, see: Setting the number of columns and designing a border for a legend on page 380 Adding a title to the legend on page 380 Adding styles to a legend on page 381 Creating a design for sections in a legend on page 383 Organizing legend columns on page 384 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Creating a design for sections in a legend Once you have decided the groupings that you want in the legend (see Organizing sections in a legend on page 382 ), you can define the font for the titles and the design for the delimiters. 1. In the Legend Properties dialog box, click the Structure tab. 2. Select a section title in the Legend hierarchy box. The default section titles are Base Section, New Group, and Default Section. 3. Enable the Show section title check box. 4. Click the Title style button and create a title style (see Selecting a style on page 354 ). 5. Click the Item text style button and create an item text style (see Selecting a style on page 354 ). 6. Click the Delimiter style button and create a delimiter style (see Selecting a style on page 354 ). 7. Enable one of the following Sample placement options to determine which side the samples appear in the legend: Left: places the samples on the left followed by their descriptions Right: places the descriptions followed by samples on the right 8. Click Advanced and determine the position of descriptions, the size of samples, the position of section titles, and the length of delimiters. For more 383

386 information, see Customizing a section layout on page 384. If you want to change the selected section or subsection title, click it and type a new title. 9. Click OK. See also Setting the number of columns and designing a border for a legend on page 380 Adding a title to the legend on page 380 Adding styles to a legend on page 381 Organizing sections in a legend on page 382 Organizing legend columns on page 384 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Customizing a section layout Using the legend advanced properties, you can customize the alignment and spacing of the legend titles, subtitles, and delimiters, and determine the size of the color, symbol, and pattern samples. 1. In the Legend Properties dialog box, click the Structure tab and click Advanced. 2. Enable one of the following Description alignment options: Left: aligns the description or label for the sample to the left Right: aligns the description or label to the right 3. Enter a value that represents the indent between the left border and the left side of the legend in the Left spin box and choose a unit of measurement from the list box. 4. Enter a value that represents the indent between the right border and the right side of the legend in the Right spin box. If you want to have both the left and right sides the same distance from the border, enable the Keep equal check box. 5. Enter a value that represents the space between each item in the list in the Inter-item spacing spin box. 6. In the Sample size area, enter a value representing the width and height of the box in the Width and Height spin boxes. 7. In the Section title area, enable an Alignment option. 8. Enter a value that represents the spacing above and below the title in the Above and Below spin boxes. 9. Enable the Delimiters check box. 10. Enter a value for the Minimum length, Lead, and Tail spin boxes for the delimiters. 11. Click OK. Organizing legend columns 384

387 You can specify the list item that appears at the top of each column, customize the width and margins of the individual columns, and define a style for a border. 1. In the Legend Properties dialog box, click the Columns tab. 2. Choose the number for the column you want to edit in the Edit column list box. 3. Choose the legend item that you want listed as the first item in the selected column in the Select start item for this column list box. If you want to reinstate the default, click Reset start items. 4. Enter a value that represents the width of the selected column in the Width spin box and choose a unit of measurement from the list box. 5. If you want all columns to be of equal width, enable the Keep all columns same width check box. 6. Enter a value that represents the distance between the left border and the left side of the legend items in the Left spin box. 7. Enter a value that represents the distance between the right border and the right side of the legend items in the Right spin box. If you want to keep the margin sizes equal, enable the Keep equal check box. 8. Enable the Show column border check box. 9. Click the Style button and create a style (see Selecting a style on page 354 ). 10. Click OK. See also Setting the number of columns and designing a border for a legend on page 380 Adding a title to the legend on page 380 Adding styles to a legend on page 381 Organizing sections in a legend on page 382 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Adding a picture to a map You can add a picture, such as an image, a graphic, or a logo to a Map. The picture is anchored to the neatline or to the Area if a neatline is not set and is positioned in reference to that anchor. To add a picture to an Area, see Creating a surround on page 371. To open the Picture Properties panel, see Setting surround element properties on page From the Maps tree, right-click a picture element and click Properties. 2. Click the General tab and click Browse. 3. In the File Selector dialog box, locate and select a file, and click Open. 4. In the Picture Properties dialog box, enter a value that represents the horizontal size of the picture in the Width spin box and select a unit of measurement from the list box. 385

388 5. Enter a value that represents the vertical size of the picture in the Height spin box. 6. Click OK. See also Setting the updating behavior on page 395 Selecting an existing quick style on page 397 About north arrows North arrows are graphical representations indicating where north is in the Area. By default, north arrows are placed vertically in the Area, which usually points north, except in a rotated Area (Raster Up). When you create a north arrow in a rotated Area, the north arrow is rotated by the amount set in the Area properties. For more information, see About Rotated Rasters on page 34. North arrows are anchored to a neatline or to an Area if a neatline is not set, and are positioned in reference to that anchor. Focus offers three arrow types: True North: the arrow points to geographic north pole where the lines of longitude converge. Magnetic North: the arrow points to the magnetic north pole, which is the direction indicated by a magnetic compass. Grid North: the arrow points in a northerly direction along a grid line parallel to the central meridian of the Area projection. This arrow is most often used in topographic maps. You can add more than one north arrow to an Area and set each arrow property separately. Several default symbols are available; you can also use the Symbol Editor (see Designing a symbol on page 360 ) to design your own. To add a north arrow to an Area, see Creating a surround on page 371. To open the North Arrow Properties dialog box, see Setting surround element properties on page 372. To define a North Arrow, see: True North (see Setting the angle and style for a true North arrow on page 386 ) Magnetic North (see Setting the angle and style for the magnetic north arrow on page 387 ) Grid North (see Setting the angle and style for the grid north arrow on page 388 ) Position (see Setting the updating behavior on page 395 ) Quick Style (see Selecting an existing quick style on page 397 ) Setting the angle and style for a true North arrow A True North arrow is a symbol that indicates the direction of the geographic north pole in an Area. For more information, see About north arrows on page From the Maps tree, right-click an arrow element and click Properties. 2. In the North Arrow Properties dialog box, click the 386

389 True North tab and enable the Show true north arrow check box. 3. Enter a value that represents the counterclockwise rotation that you want to apply so that the arrow points north in the Angle spin box and choose a unit of angular measurement from the list box. 4. Click the Style button and create an arrow style (see Selecting a style on page 354 ). 5. Enable the Show arrow label check box and choose a label from the list box. If you want to customize the position of the label, click Advanced. 6. Click the Style button and create a font style (see Selecting a style on page 354 ). 7. Click OK. See also Setting the angle and style for the magnetic north arrow on page 387 Setting the angle and style for the grid north arrow on page 388 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Adjusting the position of a north arrow label 1. In the North Arrow Properties dialog box, click the True North tab and click Advanced. 2. In the North arrow heading - Advanced dialog box, enter a value that represents the space between the arrow and the label in the Distance from arrow spin box and choose a unit of measurement from the list box. 3. Enable one of the following Angle options: Custom: adjusts the angle of the label. Enter a value that represents the rotation that you want in the spin box and choose a unit of measurement from the list box. Perpendicular: changes the angle of the label so it is vertical to the baseline of the map Parallel: changes the angle of the label so it coincides with the baseline of the map 4. Enable one of the following Alignment options: Left: places the label to the left of the arrow Center: centers the label over the arrow Right: places the label to the right of the arrow 5. Click OK. Setting the angle and style for the magnetic north arrow 1. In the North Arrow Properties dialog box, click the Magnetic North tab and enable the Show magnetic north arrow check box. 2. Enter a value that represents the counterclockwise rotation that you want to apply so that the arrow points north in the Angle box and choose a unit of angular measurement from the list box. 3. Click the Style button and create an arrow style 387

390 (see Selecting a style on page 354 ). 4. Enable the Show arrow label check box and choose a label from the list box. If you want to customize the position of the label, click Advanced. 5. Click the Style button and create a font style (see Selecting a style on page 354 ). 6. Click OK. See also Setting the angle and style for a true North arrow on page 386 Setting the angle and style for the grid north arrow on page 388 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Setting the angle and style for the grid north arrow 1. In the North Arrow Properties dialog box, click the Grid North tab and enable the Show grid north arrow check box. 2. Enter a value that represents the counterclockwise rotation that you want to apply so that the arrow points north in the Angle box and choose a unit of angular measurement from the list box. 3. Click the Style button and create an arrow style (see Selecting a style on page 354 ). 4. Enable the Show arrow label check box and choose a label from the list box. If you want to customize the position of the label, click Advanced. 5. Click the Style button and create a font style (see Selecting a style on page 354 ). 6. Click OK. See also Setting the angle and style for a true North arrow on page 386 Setting the angle and style for the magnetic north arrow on page 387 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 About scale bars A scale bar is a visual aid to help you measure actual ground distances in an Area. It is marked with measurement units in proportion to the scale of the Area. Scale bars are anchored to a neatline or to an Area if a neatline is not set and are positioned in reference to that anchor. You can create two types of scale bars: 388

391 Line and Tick Bar If you want to show two different scales, such as kilometers and miles, you must create two separate scale bars. If you want both scale bars lined up at zero, you must align them manually. To add a scale bar to an Area, see Creating a surround on page 371. To open the Scale Bar Properties panel, see Setting surround element properties on page 372. The look of a scale bar is determined by its: General properties (see Determining the style and position of the title for the scale bar on page 389 ) Scale bar type (see Selecting a scale bar type on page 390 ) Division (see Setting the divisions for the scale bar on page 390 ) Subdivision (see Setting subdivisions for a scale bar on page 392 ) Style (see Designing a Line and Tick scale bar on page 393 ) Position (see Setting the updating behavior on page 395 ) Quick Style (see Selecting an existing quick style on page 397 ) Determining the style and position of the title for the scale bar 1. From the Maps tree, right-click a scale bar and click Properties. 2. In the Scale bar Properties dialog box, click the General tab and enable the Show title check box. 3. Type a title for the scale bar in the Show title box. By default, the title is the current scale in the Area. 4. Click the Style button and create a font style of the scale bar title (see Selecting a style on page 354 ). 5. Enable one of the following options for the title placement: Above: displays the title on top of the scale bar Below: displays the title under the scale bar 6. Enable a title Alignment option. 7. Enter a value that represents the space between the title and the scale bar in the Distance from scale bar box, and choose a unit of measurement from the list box. 8. Click OK. See also Selecting a scale bar type on page 390 Setting the divisions for the scale bar on page 390 Setting subdivisions for a scale bar on page

392 Designing a Line and Tick scale bar on page 393 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Selecting a scale bar type 1. From the Scale bar Properties dialog box, click the Scale bar type tab. 2. Enable one of the following options: Line and Tick : uses a Line and Tick scale bar. Single bar: uses a scale bar type with one row Double bar: uses a scale bar type with two rows Triple bar: use a scale bar type with three rows 3. Click OK. Selecting an existing quick style on page 397 Setting the divisions for the scale bar A scale bar is separated into sections called divisions. Divisions represent the actual ground distances as displayed in an Area. To provide a greater degree of accuracy, you can provide smaller increments by subdividing a division, as shown in the following example. Divisions and subdivisions can display headings that indicate the distance in the selected measurement unit. See also Determining the style and position of the title for the scale bar on page 389 Setting the divisions for the scale bar on page 390 Setting subdivisions for a scale bar on page 392 Designing a Line and Tick scale bar on page 393 Setting the updating behavior on page From the Scale bar Properties dialog box, click the Division tab and enable the Automatic divisions check box. If you want to manually set the number of divisions, disable the Automatic divisions check box, enter the number of divisions that you want in the Number of divisions spin box, enter a value that represents the real distances on the ground that the division covers in the Division size spin box, and 390

393 choose a unit of measurement. If you want to display a unit of measurement on the scale bar and set which tick represents zero, click Advanced. 2. Enable the Show headings check box. 3. Click the Style button and create a heading font style (see Selecting a style on page 354 ). 4. Enable one of the following Placement options: Top: places the headings on top of the divisions Bottom: places the headings under the divisions For the Line and Tick scale bar type, ticks are placed on the same side as the headings. 5. Enter a value that represents the space between the headings and scale bar in the Distance from scale bar spin box and choose a unit of measurement from the list box. 6. Click OK. See also Determining the style and position of the title for the scale bar on page 389 Selecting a scale bar type on page 390 Setting subdivisions for a scale bar on page 392 Designing a Line and Tick scale bar on page 393 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Labeling a scale bar with a unit of measurement and setting a zero tick You can specify where a unit of measurement is displayed on a scale bar and which tick represents zero. 1. From the Scale bar Properties dialog box, click the Division tab, disable the Automatic divisions check box, and click Advanced. 2. In the Scalebar Divisions - Advanced dialog box, enable any of the following check boxes: Place units label at the start of scale bar: displays a unit of measurement to the left of the scale bar. Choose a unit of measurement from the Label list box. Place units label at the end of scale bar: displays a unit of measurement to the right of the scale bar. Choose a unit of measurement from the Label list box. 3. Click the Style button and create a label font style (see Selecting a style on page 354 ). 4. Enter a number of the tick on your scale bar where 391

394 you want the zero mark to appear in the Zero is at tick spin box. 5. Click OK. Setting subdivisions for a scale bar To provide a greater degree of accuracy, you can provide smaller increments by subdividing a division. the headings and scale bar in the Distance from scale bar spin box and choose a unit of measurement from the list box. 7. Click OK. See also Determining the style and position of the title for the scale bar on page 389 Selecting a scale bar type on page 390 Setting the divisions for the scale bar on page 390 Designing a Line and Tick scale bar on page 393 Setting the updating behavior on page 395 Selecting an existing quick style on page From the Scale bar Properties dialog box, click the Subdivisions tab and enable the Show subdivisions check box. 2. Enter the number of subdivisions you want in the scale bar in the Number of subdivisions spin box. If you want to specify how many and which divisions to subdivide, click Advanced. 3. Enable the Show headings check box. 4. Click the Style button and create a font heading style (see Selecting a style on page 354 ). 5. Enable a heading Placement option. 6. Enter a value that represents the space between Specifying which divisions to subdivide You can choose the number of subdivisions you want in a scale bar and where to show the subdivisions. For example, one subdivision in the scale bar can be displayed in the second division, as shown in the following illustration. 392

395 You can also choose the colors for a scale bar pattern: 1. From the Scale bar Properties dialog box, click the Subdivision tab and click Advanced. 2. In Scalebar Subdivisions Advanced dialog box, enter the number of divisions you want to subdivide in the Divisions to subdivide spin box. 3. Enter the number of the division where you want to begin showing the subdivisions in the Starting at division spin box. 4. Click OK. Designing a Line and Tick scale bar For a Line and Tick scale bar, you can determine the color, thickness, and height of the ticks. For a Single, Double, or Triple scale bar, you can determine the color and pattern of the divisions and subdivisions, and the height and the outline. For example, in a Line and Tick scale bar, the ticks can overlap the scale bar as shown: 1. In the Scale bar Properties dialog box, click the Scale Bar Type tab and enable the Tick and Line option. 2. Click the Style tab. 3. In the Scalebar area, click the Style button and create a style for the bar (see Selecting a style on page 354 ). If you want the ticks to overlap the scale bar, enable the Center ticks vertically on scale bar check box. 4. In the Division Ticks area, click the Style button and create a division ticks style (see Selecting a style on page 354 ). 5. Enter a value that represents the length of a division tick in the Tick height spin box. 6. In the Subdivision Ticks area, click the Style button and create a subdivision ticks style (see Selecting a style on page 354 ). 7. Enter a value that represents the length of the subdivision tick in the Tick height spin box. 8. Click OK. Designing a single, double, or triple 393

396 scale bar 1. In the Scale bar Properties dialog box, click the Scale Bar Type tab, enable the Single bar, Double bar, or Triple bar option, and click the Style tab. 2. In the Colors area, click any section box and choose a color from the color palette. 3. Enter a value that represents the total height of all sections in the scale bar in the Scale bar height spin box and choose a unit of measurement from the list box. For a triple-bar style, you can set the height of the middle row differently than the top and bottom rows by entering a value representing the height of the middle row of the scale bar in the Middle section height spin box. 4. Enable the Show outline check box and click the Style button to create an outline style (see Selecting a style on page 354 ). 5. Click OK. See also Determining the style and position of the title for the scale bar on page 389 Selecting a scale bar type on page 390 Setting the divisions for the scale bar on page 390 Setting subdivisions for a scale bar on page 392 Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Adding a map title to an area You can add a title and subtitle to an Area, adjust their positions, and change their font styles. The title and subtitle are anchored to a neatline or to the Area if a neatline is not set and positioned in reference to that anchor. To add a title and subtitle to an Area, see Creating a surround on page 371. To open the Title Properties panel, see Setting surround element properties on page From the Maps tree, right-click a title element and click Properties. 2. Click the General tab and type a title for the Area in the Title box. 3. Click the Style button and create a font style (see Selecting a style on page 354 ). 4. Enable the Subtitle check box and type a subtitle in the box. If you want to change the font of the subtitle, click the Style button and create a style (see Selecting a style on page 354 ). 5. Enter a value that represents the space between the title and subtitle in the Spacing from title spin box and choose a unit of measurement from the list box. 394

397 6. Enable one of the following Alignment options: Left: aligns the title and subtitle to the left Center: centers the title and subtitle Right: aligns the title and subtitle to the right 7. Click OK. See also Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Adding text to a surround You can include a paragraph of text with the other Map surround elements. You can set a text style, import text from another file, set the position of a paragraph, and change the Quick Style format of the paragraph text. A paragraph element is anchored to a neatline or to the Area if a neatline is not set and positioned in reference to that anchor. Multiple styles are not allowed in individual text elements. You can also rotate a paragraph. Text remains perpendicular to the baseline of the element. To add a text to an Area, see Creating a surround on page 371. To open the Paragraph Properties panel, see Setting surround element properties on page From the Maps tree, right-click a paragraph element and click Properties. 2. Click the General tab and type in the Text box. If you want to change the font of the text, click the Style button and create a style (see Selecting a style on page 354 ). 3. Enter a value that represents the angle of rotation you want to apply to the text in the Angle spin box and choose a unit of angular measurement from the list box. If you want to import text from a text file, click Import Text, locate and select a file in the File Selector dialog box, and click Save. 4. Click OK. See also Setting the updating behavior on page 395 Selecting an existing quick style on page 397 Setting the updating behavior Depending on the type of surround element, the positioning method differs: For Neatline: The position of a neatline is calculated relative to the extents of the Area. For Border and Grid: The position of a border and grid is calculated relative to the extents of a neatline. If no neatline is used, the positions are calculated relative to the extents of the Area. 395

398 For Legend, Picture, North Arrow, Scale bar, Title, and Paragraph: Elements are anchored to a neatline and are positioned in reference to that anchor. If no neatline is used, the surround element positions are calculated relative to the extents of the Area. The location of a surround element is determined by the Offset, which is the horizontal (X) and vertical (Y) coordinates measured from the anchor. You can see the neatline or the Area represented by a rectangle with white handles. The surround element is represented by a rectangle with gray handles. You can anchor any one of the surround element handles to any one of the neatline or Area handles. To change the location of a surround element, you can drag the surround element by its handle, or you can enter new values. If you want to modify the neatline or Area after you have set the properties for the surround elements, you can set how they behave: Reposition: the surround element automatically adjust its position in correlation with a neatline (or Area), but retains its original settings. Regenerate: the surround element is recalculated and positioned based on new settings for a neatline (or Area). This behavior is useful for the neatline, border, grid, and scale bar elements. Do nothing: the surround element does not adjust to the new settings and remains as originally positioned. 1. From the Maps tree, right-click a surround element and click Properties. 2. In the surround element Properties dialog box, click the Position tab. 3. In the Updating area, choose how you want the surround element to react when a neatline (or Area) changes position from the When neatline/area moves list box. 4. Choose how you want the surround element to react when the scale of a neatline (or Area) changes from the When area/neatline is rescaled list box. 5. In the When area/neatline is resized list box, choose how you want the surround element to react when a neatline (or Area) is enlarged or reduced in size. 6. Click Apply. Setting the offset (not available for neatline, border, and grid) 1. In the Offset area, enter a value for the horizontal position in the X spin box and a value for the vertical position in the Y spin box. You can also click a gray handle and drag the surround element into position. 2. In the preview area, click a gray handle. 3. Click a white handle to determine the anchor point. By default, the origin of a starting point of a grid is the lower-left corner of a neatline. Setting a grid starting point 1. Enable the Use starting point check box. 2. Enter an X-coordinate for the new starting point in the X spin box. 3. Enter a Y-coordinate for the new starting point in the 396

399 Y spin box. 2. In the surround element Properties dialog box, click the Quick Style tab. 3. Select a custom Quick Style and click the Remove QS button. Creating a custom quick style As you set the properties for surround items, you build a Current Working Style. You can save the settings for a surround element in a Quick Style. Understanding Grids Selecting an existing quick style 1. From the Maps tree, right-click a surround element and click Properties. 2. In the surround element Properties dialog box, click the Quick Style tab. 3. Select a Quick Style. 4. Click OK. Removing a custom quick style from the list 1. From the Maps tree, right-click a surround element and click Properties. When you select a Quick Style, the settings are copied to the Current Working Style and are applied to the surround item. If you change the properties, the changes are applied to the Current Working Style, not to the Quick Style. 1. From the Maps tree, right-click a surround element and click Properties. 2. In the surround element Properties dialog box, make changes to the properties of the surround element. 3. Click the Quick Style tab and click the Add QS button. If you want to rename the new Quick Style, double-click it, type a name, and press Enter. Creating an index for a project, you must provide Indexing a Map means you extract information, sort it as text information, and present it as part of a surround. For example, you can create an index of streets, cities, 397

400 buildings, or parks, or a combination of these. An index lists the Map locations and features. The names of the items are usually listed in alphabetical order. You can use combinations of letters and numbers that correspond to grid locations on the Map. 1. Index Information: All content used in the index matching specified conditions. You can compose a list of these items. 2. Information: A reference that identifies a location for each item in the index, information matches specified conditions. You can specify grid information. Adding a default index to a map 1. On the toolbar, click Map View Mode. Note: The image must be in Map View Mode for the Indexation dialog box to be accessible. 2. From the Maps tree, right-click an Area and click Indexation. 3. In the Indexation dialog box, click OK. Indexation properties You can set the properties for an index, including filters and lists. and building names. You can also edit redundant words, such as #street# from appearing in the index. Index List: Generates an alphabetical listing of index entries with grid locations. You can add, delete, and modify list entries. Verification Mode, when enabled, is used to interactively locate a list entry within the current Map. An index is generated in its own area on a Map, which is designated as Indexation. There is only one layer in an index area. A grid created by the index is also generated in its own area on the Map and is designated as Index. There is only one layer in a grid area. Setting general parameters for an index You can set the number of columns, column spacing, and RepCode for an index. Filtering: Specifies the type of information you want to include in an index. For example, you may want to include only road 398