I have a point cloud (.ply format) that I got after using Structure from motion techniques (with MicMac). I would like to calculate its volume with r.report in GRASS. Will r.report work on a ply file? If not, how can I convert my file into something that will work with r.report?
You can import PLY files with v.in.ply which creates a GRASS GIS vector map from a PLY file (install v.in.ply with g.extension). Then you can set the computational region to this vector map, set an appropriate raster target resolution at the same time and convert or interpolate it to a raster map for the volume calculation.
As Marion mentioned in the comments of the other answer, this error can be caused by whitespace at the end of each vertex line. I'm adding an expanded answer so that google makes it easier to find.
In my case, I used Colmap to generate binary .ply, then MeshLab to convert the binary version to ascii. I used all combinations of options in MeshLab export, including and excluding face flags, flags, colors, and normals, and GRASS v.in.ply gave two different error messages:
ERROR: Wrong number of properties
ERROR: PLY faces must have only one property
The second occurs any time face properties are included, but the first is fixable by removing the trailing space on each line.