USE OF MONOCULAR GROUPINGS AND OCCLUSION ANALYSIS IN A HIERARCHICAL STEREO SYSTEM

We describe a hierarchical stereo system that computes a hierarchy of descriptions up the surface level from each view using a perceptual grouping technique and matches these features at the different levels, With the description and correspondence processes going hand in hand, we allow high-level abstract features to help reduce correspondence ambiguities, and we exploit the multiple views to help confirm the different levels of descriptions in the scene. Occlusion is a major problem in stereo analysis and is often not treated explicitly. We present a basic property of occlusions in stereo views and show how we can use this property incorporated with the structural descriptions to identify different types of occlusions in the scene, In particular, we identify depth discontinuities and limb boundaries and infer properties of surfaces that are visible only in one of the stereo views, We give some experimental results on scenes with curved objects and with multiple occlusions. (C) 1995 Academic Press, Inc.