IMAGE/OBJECT BASED CLASSIFICATION TOOL Developed by NASA DEVELOP at BLM at ISU GIS TReC, Pocatello, Idaho

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1 IMAGE/OBJECT BASED CLASSIFICATION TOOL Develped by NASA DEVELOP at BLM at ISU GIS TReC, Pcatell, Idah 1. Intrductin This image/bject based classificatin tl was develped by NASA DEVELOP participants in The bjective f this tl is t imprve the fire cmmunity s access t infrmatin regarding Juniper land cver, tree density, and frequency. This tl uses multiband Imagery and pint data t classify different vegetatin types. It is designed t calculate the resulting classificatin s density f juniper (class value 5). These results are then interpreted t identify juniper management phase. Phase categries are: Phase 1 = >1 and <= 15% juniper cver Phase 2 = >15 and <= 45% juniper cver Phase 3 = > 45% juniper cver T use this tl, yu will need ArcGIS and the Gestatistical Analyst Extensin. 2. Dwnlad and Extract Image/Object Classifier tl 1. Dwnlad sftware frm; 2. Unzip the file t yur cmputer. Fr this exercise we will be using the C:\Data flder 3. Open the Image/Object Classifier tl in ArcMap 1. Frm Windws Explrer Navigate t C:/Data Classificatin Tl_Dcuments Duble-click the Classificatin.mxd This ArcMap dcument will cntain the vegetatin pints layer yu can use in classificatin, a link t Idah NAIP imagery, and an Example Area plygn 4. Define the Area f Interest (AOI) 1. In this example the area f interest has been created fr yu (Example Area) This represents a sample AOI that yu will use in yur vegetatin classificatin. 5. The Vegetatin Pint Feature Class 1. The Veg_Pints feature class, which (fund in the table f cntents (TOC)), will be used t identify knwn vegetatin sites. 2. Pre-defined vegetatin types have been created fr yu.

2 6. Edit Vegetatin Classificatin Pints 1. Start adding pints that will be used t classify the imagery. Frm the editr tl bar, click Start Editing Select the Veg_Pints feature class In the Create Features Pane, select a specific vegetatin type t map. In this step, yu are shwing ArcGIS pints where yu knw this specific cver type exists. If the Create features pane des nt display autmatically, lcate this icn in yu editr tl bar. Select the Veg_Pint type yu want t digitize frm the Create Feature pane Zm in, ut, and arund yur area f interest t place as many knwn pints as yu can. Peridically save yur edits Nte: yu d nt need pints fr each VegType categry. Only thse f interest t yur current prject. 2. When dne adding pints; Save edits Stp editing TIPs: T accelerate re-draw perfrmance, right click the image service and select prperties. Click the extent tab, and set the extent t yur AOI plygn feature class. During digitizing, if yu wish t pan the map, hld dwn c n yur keybard and yu will be able t pan acrss the imagery withut having t first select the pan tl. 7. Run the Tl 1. Enable the Gestatistical Prcessing Extensin Click Custmize Extensins Check Gestatistical Analyst 2. Open the tl frm ArcTl Bx ; Frm the OBJ_Based_Classificatin tl bx Duble click the OBJ Based Classificatin tl Set the fllwing parameters Area f Interest = AOI plygn feature class (Example Area) Output Name = users chice (used as a prefix fr all utput names) Vegetatin Pints = Veg_Pints pint feature class

3 Output File Path = Create a new flder inside the utput flder 3. Click OK Prcessing will take sme time and is a functin f the size f yur AOI, the number f bands f imagery used in the classificatin, and the number f vegetatin types being classified. Results All the resulting feature classes, tiffs, r tables will be added t the Table f cntents (TOC) and the Output flder yu selected as the utput file path. Fur layers will be added t the TOC _Juniper_Phase Divides the study area int 1 acre blcks t calculate percent juniper cver (this is based n tp-mst canpy and des nt take int accunt understry vegetatin) Phase categries are calculated as: i. Phase 1 = >1 and <= 15% juniper cver ii. Phase 2 = >15 and <= 45% juniper cver iii. Phase 3 = > 45% juniper cver _Pivit_Table This table will shw yu hw yur pints were classified and can be used t identify misclassificatins. _Juniper.tif Displays nly thse pixels classified as juniper _Classificatin.tif Displays the fully classified raster layer Reading the Results 1. The Juniper_Phase layer; Open the Phase attribute table The tw clumns t pay clse attentin t are the Percentage and Phase clumns The percentage clumn tells yu the percent cver in a given acre The Phase clumn labels each acre depending n its phase categry T view the plygn crrespnding t a given recrd, simply select that recrd

4 2. The Pivt Table; The pivt table is actually a matrix. T interpret this table yu will need t knw what the cded values are fr each Veg type. See the table belw Cded Value Vegetatin Type Red Green Blue 1 Sagebrush Bare Grund Cheatgrass Other/Nn-Vegetated Juniper Aspen Duglas Fir Maple Ldge ple Pine Muntain Mahgany Reading the example table (abve): RASTERVALU 1 and VegType1 (sagebrush) have an agreement between 14 pints. Meaning 14 pints were crrectly classified as sagebrush. Hwerver, three sagebrush pints were misclassified as VegType2 (bare grund).

5 2. The_Juniper.tif Classified Juniper nly 3. The _Classificatin.tif All Classified Juniper = Light Blue Sagebrush = Dark Blue Bare Grund = Medium Blue

6 Apply a Clrmap 1. T add a clrmap t the _Classificatin.tif r _Juniper.tif; Open the layer s Prperties Click Symblgy Select Unique Values Click the Clrmap drpdwn Select Imprt Clrmap Navigate t the.clr file in the TlData flder Click Apply 2. Repeat fr _Juniper.tif Clr Map Applied Sagebrush Bare Grund Juniper

7 Title: OBJ Based Classificatin Descriptin: Object Based Classificatin using Multiband Imagery and Pint class t classify vegetatin type. This tl als als calculates the classificatins Cell density f value "5"(Juniper) This density is then visualized using a fishnet t identify the Juniper phase. Limitatins: Pints feature Class has t be lcated in the Classifcatin Gedatabase lcated in "..\Classificatin\TlData\Classificatin.gdb". This allws the "Class" Dmain t be applied t the VegType field. This dmain cntrls the Cded Values. Authrs: Ryan Hwertn (hweryan@isu.edu) Jenna Williams (will55200@gmail.cm) Prject Lead Sara Rams Created: 4/8/16