Integrating LiDAR data into the workflow of cartographic representation.

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Jeffry Harmon
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1 Integrating LiDAR data into the workflow of cartographic representation.

2 Cartographic Workflow I Surveying Vector (Nat. GDB) GPS, Laser Range Finder Yes/ No Scanning old maps LiDARflights Capture technical data Raster data (WMS) Digital elevation models Technical data (DB, Lists) Orthophotos & DEM while vectorizing: Contour lines Road & tracks Vegetation Cliffs Others Open Street Map Complete

3 Cartographic Workflow II Editing Vectors Mobile devices 9 Course Setting Topological Adjustments GDB, WMS Routing (OSM) Editing Raster Web maps Editing DB Printing

4 Orienteering Maps. 8 Years ago: LiDAR data / DEM / Tablets (OCAD 10/11) Base map: Digital Survey Maps / WMS / LiDAR data Contour lines Relief shading Slope map Density Maps Intensity Maps Surveying: GPS Receiver Tracks Laser Range Finder Tablet PC

5 Cartographic Workflow I Yes/ No Surveying Scanning old maps LiDARflights Capture technical data Vector (Nat. GDB) Raster data (WMS) Digital elevation models Technical data (DB, Lists) GPS, Laser Range Finder Orthophotos & DEM while vectorizing: Contour lines Road & tracks Vegetation Cliffs Others Open Street Map Complete

6 Cartographic Workflow II. O maps Editing Vectors O maps O maps Mobile devices 9 O maps Course Setting Topological Adjustments GDB, WMS Routing (OSM) Editing Raster Web maps O maps Editing DB Printing

7 LiDAR Data. RGB Photo GRID Laser Raw Data Hill Shading Contour Lines DSM DTM

8 Contour Lines. Individual contour interval. Problem: Large file of Danish Land Survey with 36 km 2 several days Solution: Split into tiles of 1km km 2 6 minutes and merge contour lines afterwards!

9 Contour Lines. Problem: jagged contour lines Solution: 1 st use Douglas Peucker Algorithm and 2 nd change into Bèzier Curve.

10 Contour Lines. Problem: differentiate depressions from hills Solution: Combine with hill shading picture

terrain, like trail and track network ditches and depressions hills

11 Hill Shading. Open hill shading as background map and vectorize the shape of terrain, like trail and track network ditches and depressions hills The quality of the hill shading can differ due to the quality of the resolution. Experienced user can detect vegetation boundaries as well.

12 Contour Line vs. Hill Shading

13 Orthophoto. Open georeferenced orthophotos as a background map and vectorize vegetation edges. Quality can differ a lot, due to the date of the shot. Restriction due to shadow and stage of vegetation

14 Vegetation Height Maps. Calculate difference from Digital Surface Model (DSM) and Digital Terrain Model (DTM) Classify the differences. More distinct than orthophotos

15 Vegetation Height Maps. Orthophotos vs. Vegetations Heights Maps (DSM minus DTM)

16 Vegetation Height Maps. Orthophotos vs. Vegetation Heights Maps (DSM minus DTM) Illustration: B. Imhof, U. Steiner

17 Cliffs Calculate slope map Classify all slopes (pixels) more than 45

18 Is this workflow useful only for orienteering maps?

Contour lines and hill Nomenclature shading Properties are missing!

19 Data of Official Survey in Switzerland. 11 Thematic Layers Survey marks Ground cover Single objects Heights (DEM) Contour lines and hill Nomenclature shading Properties are missing! Piping Boundaries Permanent erosion and mudflow Address of houses Administrative boundaries Source : Toilets for dogs

20 Survey Map 1: Raw data (DXF) Individual visualization With relief shading and toilets for dogs

21 Cartographic Workflow I Yes/ No Surveying Scanning old maps LiDAR flights Survey Maps Capture technical data Vector (Nat. GDB) Raster data (WMS) Digital elevation models Survey Maps Technical data (DB, Lists) GPS, Laser Range Finder Orthophotos & DEM while vectorizing: Contour lines Road & tracks Vegetation Cliffs Others Open Street Map Complete Survey Maps

22 Cartographic Workflow II. O maps Editing Vectors Survey Maps O maps Survey Maps Survey Maps Survey Maps Mobile devices 9 O maps Course Setting Survey Maps Topological Adjustments GDB, WMS Survey Maps Survey Maps Routing (OSM) Editing Raster Survey Maps Web maps Survey Maps Editing DB Printing O maps

23 Conclusion. Laser Airborne Scanning has revolutionized orienteering maps very much: Products: Contour lines Hill shading Cliffs Vegetation Height Maps This manner to complete maps is not only practicable for orienteering maps, it is suitable also for other topographic maps.

24 Thank you for your attention!

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