georeferenced pointclouds

[msc818]

Hi everyone!
For my bachelor thesis I created pointclouds of trees to measure the diameter. For half of the point clouds I used a 3D ImageVector --Mono-- PPK camera attachment, which georeferences each photo with GNSS data.
My problem is, that I cannot open the georeferenced point clouds in cloud compare. The project is visible in the DB Tree section, but not in the main part. (picture attached)
Is there something I can do to make them visible?
Thanks for any help!

[daniel]

It can happen if all the points are at the exact same position (it may be the case in the file, or it's maybe because there's a reading error).

Can you send me the file maybe? (admin [at] cloudcompare.org)

[msc818]

I have the same problem with 8 data sets so far.

The ply file seems to be too big to send by email, is there another way?

[daniel]

wetransfer?

[TMC]

For my bachelor thesis I created point-clouds of trees to measure the diameter.

Since I'm working with tree point-clouds as well for my bachelor thesis, I want to suggest you another software: CompuTree. It is designed to measure the DBH (and lot more). Its not as sophisticated as CloudCompare, but for measuring the DBH its quite good.

(I hope this recommendation is not against the rules)

Best TMC

[daniel]

@msc818 Okay so your problem is that the points are in a strange coordinate system with XY having different units than the Z dimension.

When you load your point cloud, just rotate the camera (or look at the cloud bounding-box) and you'll see that it's elongated:

elongated.PNG (5.14 KiB) Viewed 3050 times

Either you find a way to export your points in a 'cartesian/homogenic' coordinate system, or you scale the points afterwards in CC (with the 'Edit > Scale / Multiply tool). But that's generally not a good idea when the differences in scale is that big (10^5!!!) as you'll lose a lot of accuracy.

@TMC absolutely no problem, it's not as if we were making money with CloudCompare :D

[msc818]

Thank you for your help! I think I will try if CompuTreeworks better for me.