Detect holes from point clouds

[Jenny_S]

Hi,

I am new to this software. I have a set of points forming into a spherical surface. And there are some holes on the surface. Can I use this software to find and output the properties of the holes, which can be detected from the point cloud? Just find the holes and no need to fill them. Is it possible?

Looking forwards to replies!!!! Thanks a lot.

[daniel]

Well there's no easy way to do this (far from it).

The only method that may give you something is the following:

• use the qPoissonRecon plugin to build a closed mesh of your cloud (see http://www.cloudcompare.org/doc/wiki/in ... n_(plugin)). Make sure to output the mesh 'density' as a scalar field.
• then use the scalar-field based segmentation capabilities of CC to keep only the parts of the mesh with the lowest density (they should roughly correspond to your holes)
• eventually you can segment those holes with the scissors tool. If there are too much of them, you can sample points on the holes (mesh) and use the connected components extraction tool on the resulting cloud. Anyway at the end you should get several subsets of points corresponding to each hole. For each subset you can get various pieces of information: center, contour, perimeter, surface, etc.)