CSF - adaptive threshold

[glenrs]

Hello,

First, thank you all for the amazing software. I've only just started using LiDAR (mostly for topographic surveys) and CC has helped immensely.

I use the CSF plugin to remove trees and buildings for DEM creation. I've had a lot of success by playing around with the settings and usually applying it twice to really thin the point cloud and choose only the lowest points. However, I've noticed a problem with banding when the terrain is stepped:

https://imgur.com/a/teyuUwv

(I haven't worked out how people are putting images cleanly in their posts; any help appreciated.)

I stumbled on the paper "An Adaptive Surface Interpolation Filter Using Cloth Simulation and Relief Amplitude for Airborne Laser Scanning Data" https://www.mdpi.com/2072-4292/13/15/2938 which seems like it improves the CSF method in cases of stepped terrain by adaptively altering the threshold.

I have no idea how difficult this would be to implement (I do a bit of scripting but software development is completely out of my league) but this might be a worthwhile thing to look at including in the CSF plugin?

(Also, I'm not 100% sure but I think the CSF CC plugin is maintained by the CC developers, rather than the original author? Let me know if I should be making this suggestion elsewhere.)

Regards,

Glen

[daniel]

To share images, you have to use the 'Attachments' tab below the message edition field (you can 'add files' then place them inline in the message).

And thanks for the pointer. We maintain the plugin indeed so that it can work with the latest version of CC. But the algorithm and initial version was submitted by the authors. What we can do is add this suggestion to the TODO list in case someone motivated can update the code (my only fear is that the TODO list is already huge...)