Rectangular holes or patterns in photogrammetry mesh?

[AMetner]

Hello everyone!

Going a few months back I started to have an issue when reconstructing a mesh from a photogrammetry in Reality Capture.

The finished mesh seems to have rectangular holes or sometimes a rectangle pattern in it - especially visible from the front view!

Here is what I think I found out through testing:

• The holes don’t always appear at the same spot but more or less at the same ‘area’, regardless of whether the spot was well ceptured by the camera.
• They appear on big meshes as well as smaller ones.
• The number of photos does not seem to make much of a difference. I tried reconstructing with 190 photos and with 70 photos. The holes appeared either way.

I will attach screenshots for you to see what I mean.

I found 2 or 3 entries in the Reality Capture Forum from people having the exact same problem and tried the mentioned ‘solutions’ (setting the reconstruction region anew or using high instead of normal detail) but they sadly did not work for me.
High Detail seemed to make the holes smaller, but they are still there.
Also the newest reply is from 2017, so no idea if there are any new solutions already!

The threads I found are these ones:

Rectangular holes / missing parts?

Hi there, I resumed a project recently I had to pause a while ago. It has 273 images and took 4,5 days to reconstruct in High Detail. The result is very good, however I have some rectangular holes. It looks as if some parts haven’t been calculated. All parts are set to enabled. til_0.jpg 1/ Does anyone have an idea, why these holes were generated and if I can avoid them? I had to pause the calculation several times durind the 4,5 days. My only guess is that pausing and resuming the calculati…

Issue with mesh.Holes on Normal\High reconstruction

While I’m looking for a solution on the forum, the same problem on another scan. Point cloud Preview Normal

I also updated RC to the newest version, it makes no difference.

Does anybody know anything and could help me out?

[OndrejTrhan (otrhan)]

Hi AMetner,
what are your reconstruction settings?

Here are some steps you can try:

1. Always use a reconstruction region.
2. Change the RECONSTRUCTION REGION slightly, say +10-15 % bigger and rotate it by say 10-15 degrees.
3. Set Minimal distance between two vertices (Reconstruction settings - Mesh calculation) to some value, e.g. 0.001
4. Raise the number of Maximal vertex count per part (Reconstruction settings - Advanced) to higher value, e.g. 10M or 20M

[AMetner]

Hello @OndrejTrhan

I tried your suggestions and it indeed fixed the holes!
Thank you very much!

I don’t know which point had the solution but I would gues its was the ‘Minimal distance between points’ and the ‘Maximal vertex count per part’.

Here is a screenshot to show the dix (compared to the first screenshot):