In this video we show how to use the Point Cloud Processor and Improved Point Cloud Classification tools from TBC v5.90 to find Ground in a point cloud. If you don’t have the Photogrammetry Module you cannot use the Point Cloud Classification Tools to extract the Ground Surface so Point Cloud Processor is your best solution. If you have both the Photogrammetry Module and the RPS Tools then you can use either approach to find the Ground surface in a point cloud containing a lot of tree canopy.
In TBC v5.90 the Point Cloud Classification tools have been improved, however they are still a lot slower to use than Point Cloud Processor - in addition they don’t reduce the data extracted for Ground in any intelligent way so you still end up with a very large point cloud that you still have to sample to reduce to make it usable for surface modeling, you still need to apply boundaries to limit the extents and eliminate e.g. Wetland Areas and you still have to build the surface model itself.
Point Cloud Processor in one step reduces the point cloud, finds you the ground data, applies internal and external boundaries and builds you the surface model in a single step function that is quicker to execute. You may have a few spikes to eliminate depending on the settings used but in most cases you will have the same situation with Extract Ground also. In tests we have also found that the "Ground Extracted using the Classification function is typically higher than the lowest data in the point cloud in the same locations - see the images below for details
This is the surface and points created using Point Cloud Processor
This is the data from the Extracted Ground using the Classification along the same line and using the same depth of view settings
The highest points are ~+0.5’ to the Lowest Point Surface typically which over an entire project would be a significant material quantity to take care of.
Video shows you how