Lidar Working with LAS Datasets

Transcription

1 2013 Esri International User Conference July 8 12, 2013 San Diego, California Technical Workshop Lidar Working with LAS Datasets Raghav Vemula (3D Team) Esri UC2013. Technical Workshop.

2 Agenda Las Dataset Overview Demo What's new in ArcGIS 10.2 Demo Recommendations Custom tools (3D Resource Center) Demo Future (Post 10.2) Q & A

3 LAS Dataset - Overview LAS Dataset - File based data structure - Stores references to LAS files on disk - Treats a collection of LAS files as one logical dataset - Optionally reference break-line data

4 LAS Dataset - Visualization In 2D (ArcMap) or 3D (ArcScene) As points - Symbolize using LAS attributes (Class Codes, RGB etc.)

5 LAS Dataset - Visualization As a surface - Symbolize & filter (Bare-earth, First-return, etc.) Control the number of points shown

6 LAS Dataset - Editing Manual editing (data errors, mis-classifications) Using Geo-processing tools

7 LAS Dataset - Surface definition Support for break-lines (Surface constraints)

8 GP Tool Summary 3D Analyst Conversion Data Management Conversion To Raster LAS Dataset Data Management Layers and Table Views Tools enhanced to support LAS Dataset

9 LAS Dataset - Analysis Derive surfaces - LAS Dataset As Raster - LAS Dataset As TIN Direct analysis - Interpolate Shape - Add Surface Information - Line Of Sight - Locate Outliers Rasterize on point metrics - LAS Point Statistics As Raster

10 LAS Dataset - Spatial Reference Support Assign spatial reference (if missing) Override using a.prj file (if already present) Project Clip using an area-of-interest File extent Study Area Clipped file extent

11 Lidar data - Sharing Mosaic Dataset - Manage Lidar data like imagery - Add / remove LAS files - Add / remove LAS datasets Share the data as Image services - Easy for others to see available Lidar data - Easy to download for project work

12 LAS Dataset API for developers Freedom to work in multiple languages - Arcobjects exposed in C++,.NET, Java Access to lidar data through image services - E.g. download and query 3 rd party developers can build custom applications - E.g. Automated classification, Feature extraction, Reality augmentation

13 DEMO LAS Dataset Basics Esri UC2013. Technical Workshop.

14 New in ArcGIS Indexing LAS auxiliary file (.lasx) Improves performance of spatial queries Efficient use of larger files and files over a network Benefits both visualization and data processing Index auto-updates after editing operations

15 Index creation. Folder file1.las file2.las Add LAS Dataset Compute Stats Folder file1.las file1.lasx file2.las. file2.lasx

16 The index (.LASX) file Container file for stats and index One-to-one association with LAS file Located next to LAS file Reusable

17 New in ArcGIS Rearrange Rewrite LAS files with optimal point ordering Physical sort of point records Results in an optimized index Benefits data retrieval operations Custom GP tool will be published Utility for evaluating need for rearrangement will be available

18 LAS Dataset To Raster - Performance Improvement with Spatial Index Small files < 200MB Large files > 1GB

19 DEMO New in ArcGIS 10.2 Esri UC2013. Technical Workshop.

20 Data delivery Recommendations Rearranged LAS, including.lasx file, provided as deliverable to client Yields best performance without client needing to do anything Does not hurt non-esri clients

21 Usage Recommendations Classified LAS files organized as tiles 200 MB file size limit All participating LAS files have the same Spatial Reference (Projected CS) Data location (preferably on a local disk)

22 Licensing Standard, 3D, or Spatial Analyst License - Create LAS dataset - Modify LAS dataset schema - Include in Mosaic dataset - Publishing requires Image Server extension - View in 2D - Rasterize 3D Analyst License - Edit class codes - View in 3D - TIN based surface analysis - Rearrangement

23 3D Resource Center - Utilities CheckLAS LAS Model Key LAS To LAS Height Above Ground Ground Classifier LAS Dataset Tools

24 DEMO Custom Tools Esri UC2013. Technical Workshop.

25 Airborne Vs. Terrestrial Lidar Many tools cater to airborne Lidar data - Surface views and analysis tools - LAS attribute relevance Terrestrial lidar supported as point cloud in ArcScene - Points used as backdrop for measuring and digitizing - Display integrated with other GIS layers

26 Las Dataset Vs. Terrains Geo-database Z-tolerance pyramiding Duplication of Lidar data Editing 3D Viewing Las Dataset and Terrains are complimentary

27 Future (Post 10.2) Enhancements - Some custom tools will be provided out of the box - Ground classifier, Model key etc. - Potential new functionality - Tile, Clip, Merge - Break-line extraction - Include Z as part of point filtering - Assign RGB from photo - Fast outlier detection

28 Future (Post 10.2) Compression - Esri compressed LAS - Lossless - Transparently treated as LAS but much better for use and exploitation - Library for 3 rd party use

29 Why use 3D GIS? Because our world is 3D Improve understanding 3D is easy for everyone to understand Solve 3D problems Some spatial problems can only be solved in 3D Better communication 3D makes it easier to articulate ideas

30 What can you do with ArcGIS 3D? 3D Geodesign Multiscale 3D Models ArcGIS for 3D Cities Surface modeling Share 3D scenes Native lidar support 3D Analysis Integrated 3D

31 Thank you Please fill out the session evaluation Offering ID: 1334 Online Paper pick up and put in drop box

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