Recovering building structures from stereo

Addresses the problem of extracting polyhedral building structures from a stereo pair of aerial intensity images. The authors describe a system that computes a hierarchy of descriptions such as segments, junctions, and links between junctions from each view, and matches these features at the different levels. Such high level features not only help reduce correspondence ambiguity during stereo matching, but also allow us to infer surface boundaries even though the boundaries may be broken because of noise and weak contrast. The authors hypothesize surface boundaries by examining global information such as continuity and coplanarity of linked edges in 3-D, rather than merely by looking at local depth information. When the walls of the buildings are visible, they also exploit the relationship among adjacent surfaces in a polyhedral object to help confirm the different levels of descriptions. The authors give some experimental results for aerial images taken from overhead views and oblique views.<<ETX>>