Generating DEM only within a provided polygon

Skip to first unread message

André Kunert

May 7, 2020, 4:19:12 AM5/7/20
to LAStools - efficient tools for LiDAR processing

I have to calculate the DEM of countless small buildings. I have the footprints of the buildings as a polygon shape file. Is it possible to specify these footprints as boundaries for the "house-DOM"? Or do I first have to calculate a DOM for the whole area and then clip out the house areas again? Unfortunately I couldn't find anything in the readme file about this. For me, the areas outside the houses are not interesting, so that I don't want to calculate a DOM outside these house areas. I already tried it with -keep_class 6 -nodata -9999, but unfortunately it calculates the spaces in between anyway. Is there an hidden command?
Thanks a lot for your support.

Martin Isenburg

Jul 15, 2021, 1:08:34 PM7/15/21
to LAStools - efficient command line tools for LIDAR processing
Hello André,

if you clip the LiDAR points with a shape file such that only the building footprints remain you can create a DSM of only the buildings if you set the '-concavity 1.0' value of las2dem to something that is lower than the spacing between the buildings (but higher than the pulse spacing). However, this DSM will not have very nice edges along the buildings as the typical boundary artifacts will occur. It might lead to better results to create a spike-free DSM

that nicely preserves the building points and then clip the raster afterwards against your building footprint polygons.



Download LAStools at
Be social with LAStools at
Manage your settings at
You received this message because you are subscribed to the Google Groups "LAStools - efficient tools for LiDAR processing" group.
To unsubscribe from this group and stop receiving emails from it, send an email to
To view this discussion on the web visit
Reply all
Reply to author
0 new messages