OpenDroneMap / ODM

A command line toolkit to generate maps, point clouds, 3D models and DEMs from drone, balloon or kite images. 📷
https://opendronemap.org
GNU Affero General Public License v3.0
4.81k stars 1.09k forks source link

Feature request: option to disable OpenMVS point cloud filter (filtering by visibility) #1785

Open originlake opened 1 month ago

originlake commented 1 month ago

I noticed the OpenMVS point cloud filter might have a problem, how it determines the point visibility cannot handle when seeing a plane from side. I had a dataset that the majority of good points on a plane get removed.

Before filter before_filter

After filter after_filter

I believe the case like the red camera is causing this issue, when seeing a plane from side, every closer point occludes further points, which leads to unpredictable behavior in the visibility filtering algorithm. This might also cause points on the wall of a building removed. I can share the intermediate openmvs files if needed (scene_dense.mvs), images won't be allowed. Screenshot from 2024-07-30 12-07-21

pierotofy commented 1 month ago

Interesting find, as a workaround there's the option to skip filtering in ODM by setting pc-filter: 0, but would be awesome to improve things in OpenMVS.

smathermather commented 1 month ago

@originlake -- thanks for getting this issue into the OpenMVS queue too.