I have created a DEM, DSM, and nDSM from a LiDAR Point Cloud using SAGA-GIS. I extracted the appropriate returns from the point cloud, then converted to grid, and then closed gaps to fill in any nodata regions.
I'm finding that my resultant rasters are still pretty noisy. For example, a region of pixels in the DSM that is obviously a tree or cluster of trees has several pixels with a very similar value to ground in stead of the surrounding higher value pixels.
I've tried doing a majority filter on the DSM, but it didn't help. Any suggestions for other filters that might help create more contiguous regions of pixels?