Finding the ground truth of images without creating masks for every object?

Hi,
I would like to know if there is a way to find the ground truth of images without creating a mask for every object. Is there any post-processing technique that I can use to achieve this? For example, if I have a remote sensing image with multiple buildings, can I group all the buildings together as a single object instead of creating individual masks for each building?

The issue names no target file, test, or entry point. Start with the repository's example notebooks and inspect how masks are produced for multiple buildings; clarify whether grouping them into one object is supported, then define and document an agreed workflow or implementation before proceeding.

Written by the indexing model from the issue text.