Deriving occlusions in static scenes from observations of interactions with a moving figure

Many applications in computer vision are based on a single static camera observing a scene which is static except for one or more figures (people, vehicles, etc.) moving through it. In these applications it is useful to understand whether the moving figure is partially occluded by some static element of the scene. Such partial occlusions, when undetected, confuse the analysis of the figure's pose and activity. We present an algorithm that uses only the information provided by moving figures to simply and efficiently derive the position of static occluding bodies. Once these occlusions are obtained, we demonstrate successful reasoning about the occlusion status of future figures within the same scene. The occlusion positions from multiple views of the same scene are used to extract an estimate of the three-dimensional position and shape of the occlusion. Experimental results validating the method are included.