@maphew Re: MCC and ground filters - IMO there is no clear winner. Best to have a number of tools at your disposal. I find that the morphological ones are quite good, reasonably fast, and intuitive. But they aren’t perfect by any means. MCC caught my attention many years ago, being one of the first open source ground segmentation algorithms I was aware of. I’ve never spent any time scoping out the complexity of adding it to the mix. I suppose you could run their binary as a preprocessing step, and then bring the resulting classifications into PDAL for further analysis.