Building Verification from Disparity of Contour Points

This paper presents building verification in the context of change detection for database update. Disparity values between the left and right images of a stereo couple are estimated from grey level correlation in the vicinity of edge pixels and harmonized along contours for better coherence and accuracy. This estimation is very fast as only edge pixels are considered and accurate thanks to grey level and geometrical constraints. Building evidence is derived from the presence of edge points with high disparity near or inside building polygons of the database. Verification results compared favourably with a previous work based on straight line and shadow detection. The system intends to assist geographers in the process of topographic database update for the building layer. It also aims at delivering useful by-products like building elevation (Z coordinate) and Digital Terrain Model (DTM).