Re: grid_map versus proj_map for same bag data

Posted by brigit on
URL: http://official-rtab-map-forum.206.s1.nabble.com/grid-map-versus-proj-map-for-same-bag-data-tp1779p1791.html

matlabbe wrote

The algorithm used to create occupancy map from projection is labeling ground points as empty and obstacle points as occupied. The camera needs to "see" the ground to add empty cells.

I have a question regarding this: technically speaking, the ground is still an obstacle (albeit a flat one) with zero or minimal height. As you say, the camera sees the ground plane, but how does the algorithm know to label these ground points as empty? Is there some height threshold that is used?