Interpretation Of Geometric Structure From Image Boundaries

General constraints on the interpretation of image boundaries are described and implemented. We illustrate the use of these constraints to carry out geometric interpretation of images up to the volumetric level. A general coincidence assumption is used to derive suggestive but incomplete interpretations for local features. A reasoning system is described which can use these suggestive hypotheses to derive consistent global interpretations, while maintaining the ability to remove the implications of hypotheses which are disproved in the face of further evidence. An important aspect of interpretation is the classification of image boundaries (intensity discontinuities) into those caused by geometric, reflectance, or illumination discontinuities. These interact with other hypotheses regarding occlusion by solid objects, the direction of illumination, aspects of object geometry, and the production of illumination discontinuities by geometric discontinuities. Although only a subset of the constraints and system design features have been implemented to date, we demonstrate the successful interpretation of some simulated image boundaries up to the volumetric level, including the construction of a three-space model.