I am wondering if there is an efficient interpolation method to close the holes in a dtm resulting from groundfiltering. At the moment I am directly interpolating the point cloud to a raster using idw or kriging but finally there are dents in the dtm where for example trees where located before. In general the result is sufficient but it would be nice to know if someone found another way in R or SAGA not creating a dent or small mount. I am thinking of something like closing the gaps from outside to the inside, in extending the edges.
Try the result if you use in SAGA: Grid-Tools-Close Gaps. But first, you need to bring pointcloud to the grid. To do this use Shapes-Point Clouds- Point Cloud to Grid.