Characterize different point clouds, parameters, tools

Hello, I have a lot of different point cloud, like the following:

I'm trying to characterize them with several parameters,

I am trying to characterize them with different parameters. I would like a parameter that would allow me, even with some approximation, to distinguish for example the two yellow point clouds above: one has many more "holes" than the other.

Any idea how to do this in matlab? What index or tool to use? Thanks in advance

[Veronica Taurino]

I am currently using this as reference, but since my PCs are very different, PC with low density but without holes are classified the same the PC with big holes but closer points:

How to compute the density of a 3D point cloud? - MATLAB Answers - MATLAB Central (mathworks.com)

Answer 1

[Sarthak]

Hi Veronica,

You can try to use the Euler’s characteristic/number as a parameter to distinguish which cloud has more holes than the other. The following is the documentation for binary images. You can try to implement the same for your point clouds.

https://www.mathworks.com/help/images/ref/bweuler.html

[Veronica Taurino]

Thank you for the hint, i'm gonna try it!