Issue of Rasterize tool in the latest version and suggestion on CHM

[dan86]

Hi Daniel,
first of all many thanks for this amazing software which I know from few months but it already helped me a lot with my research.
During some tests aimed at producing a Canopy Height model from UAS-based point cloud I noticed an issue in the latest version of Cloud compare(2.12) with the rasterize tool. I suppose that is a problem because making the same steps in CC v. 9.2 all worked like a charm.
In particular, I Used CSF filter to classify my point cloud in ground points ad off grounds points and to create a cloth mesh (which seems to me something similar to bare earth DTM). Successively, I sampled 2000000 of points on the cloth mesh and I used this new point cloud to compute 2.5 Volume with off-ground points. I got another point cloud with scalar field represented by relative height of trees as you can see in the attached image (https://drive.google.com/file/d/1_U_qwi ... sp=sharing). First of all, could I ask you if you deem appropriate such method to achieve this task ? I am new to such things so any suggestion is more then welcome :-).
Now, the real odd thing: when I export as geotiff my output (choosing relative height as active layer in the grid option) I get always only a geotiff with height grids and no the relative heights (trees heights, in my case from 0 to 11.2 m) as you can see by the value read in ArcGis.
https://drive.google.com/file/d/1HpcFY_ ... sp=sharing
Moreover if I try to select "active layer" in the raster export option panel nothing is created.
Do you have some suggestion or it is preferable for now that I return to old version ?

Many thanks and all the best for this new year.
Daniele

[daniel]

Yes, the method is good.

Can you maybe share the cloud (with relative height) with me? (admin [at] cloudcompare.org)

[dan86]

Hello Daniel,
sorry but I haven't received the notification on my email so I missed your answer.
Yes of course I can share the cloud with you but since is it part of a research project if possible I would prefer to share it privately. I can sent it via email o we transfer or whatever you prefer.
Many thanks and best regrds,
Daniele

[daniel]

Yes, you can send me the link to admin [at] cloudcompare.org

[daniel]

Thanks for the data. Actually it helped me to detect an issue that looks a little bit different: if only the 'Export active layer' field is exported, and this SF is the first scalar field of the input cloud, CC would simply not save the raster?!

This is now fixed. And now, when I export this 'active scalar field' (making sure the active scalar field is 'Relative height', I get a proper geotiff file with the 'Relative height' SF values.

cc_raster_export.JPG (16.91 KiB) Viewed 4543 times

I've updated the latest 2.12.alpha version online.

[dan86]

Dear Daniel,
many thanks again for your great support and ultra quick fix!.
Ok I will download the last version asap.
All the best,
daniele