Interpreting Aerial Photographs By Segmentation And Search

A knowledge-based system for interpreting aerial photographs, Picture Query (PQ), first segments an image into primitive, homogeneous regions, then searches among combinations of these to find instances which satisfy definitions of object types. If primary evidence is insufficient, there may be an hypothesis-based search for the supporting evidence of related objects. This secondary search is restricted to windows by expected spatial relations. First instances are improved by searching for overlapping variants having better goodness-of-figure. The process may be repeated using re-estimated parameters of object definitions based on instances found previously. Results are reported for images of suburban neighborhoods, including roads, houses, and their shadows.