What does internal coordinate system mean in Agisoft Metashape ?
I have taken some images with the drone and they contain coordinates in WGS84 CRS. In Metashape documentation, I read that there is possibility to convert from internal CRS to geocentric CRS e.g. WGS84 using Python API for Metashape but I don't understand what is this internal CRS and the transformation matrix to convert ( to and from it) is computed.
Internal coordinates in this case mean, how the application treats the coordinate information internally. So it is always some arbitrary coordinate system with its own scale and orientation not related to real world.
But if the project is georeferenced, you can transform the coordinates from the internal coordinates to the real world coordinate system, as you have mentioned: using chunk transformation matrix and coordinate system .project method. This also works in the opposite way: via .unproject method for the coordinate system and inverted chunk transformation matrix.