Presentation on using ArcObjects and LAStools to combine AHN2 raster data and aerial photography to create a LAS dataset and visualize it in the new ArcGIS 10.1
Playing around with LiDAR, AHN2, Aerial Photography and LAStools in ArcGIS 10.1
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AHN2 surface and bare earth 0.5m raster dataset
Aerial Photography 0.5m
Some ArcObjects code tot create text file
LAStools to convert into LAS file
ArcGIS 10.1 + 3D analyst to create LAS dataset
Visualization in ArcGIS 10.1
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0.5m bare earth raster or bare earth + objects, but no point clouds
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Along with AHN2 you may obtain some aerial photography or
just use one of the many web services available…
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Now use IIdentify::Identify(IPoint) or the much faster
IPixelBlock3 to loop through the pixels and build a text file with
the following format:
X [TAB] Y [TAB] Z [TAB] R [TAB] G [TAB] B
Use IRasterIdentifyObj::MapTip for the RGB values, note that
the maptip gives a string with:
Red = 100, Green = 150, Blue = 200
It would be nice if ArcGIS 10.1 would offer a way to create LAS
data, but no worries that part is solved by…
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Using LAStools it is easy to convert a text file into LAS:
txt2las -i input.txt -parse xyzRGB -skip 1 -o output.las -set_version 1.2
the input file (-i) is “input.txt"
the output file (-o) is “output.las"
the first 3 columns are parsed to xyz, columns 4th to 6th to RGB
the first line (header) is skipped using "-skip 1"
the output LAS version is set to 1.2 by "-set_version 1.2"
LAStools can do a lot more!
More information on LAStools:
https://twitter.com/#!/LAStools
http://www.cs.unc.edu/~isenburg/lastools/
http://www.linkedin.com/groups/LAStools-4408378
http://www.facebook.com/LAStools
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Recently Martin released a Toolbox for ArcGIS:
… and yes, it supports ArcGIS 10.1!
More information on LAStools:
https://twitter.com/#!/LAStools
http://www.cs.unc.edu/~isenburg/lastools/
http://www.linkedin.com/groups/LAStools-4408378
http://www.facebook.com/LAStools
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The LAS file can be imported into a LAS dataset in ArcGIS 10.1
Select your files of folder
Specify the output lasd
Define any surface constraints
Coordinate system, etc …
… and hit OK
http://resourcesbeta.arcgis.com/en/help/main/10.1/index.html#/Create_LAS_Dataset/00170000016w000000/
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Use the LAS Dataset toolbar to view profile and edit classes
http://resourcesbeta.arcgis.com/en/help/main/10.1/index.html#//015w00000053000000
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Use ArcScene to show the LAS data in RGB
http://resourcesbeta.arcgis.com/en/help/main/10.1/index.html#/Point_display_options/015w0000005t000000/