Recovering 3D information from complex aerial imagery

The authors describe a comprehensive stereo analysis system developed to recover the 3D description of an urban area using high-resolution aerial imagery. Given an area of interest in terms of geographic coverage, the system can automatically find the appropriate stereo pair using a spatial database, select control points to register the two images so that epipolar geometry is satisfied, and recover disparity information using two complementary matching techniques. It is believed that stereo mapping research must explicitly address error and uncertainty in both scene registration and stereo matching. In the registration process, five different features can be automatically extracted to select control points for fine image registration. In the stereo matching process two techniques are utilized, an area-based and a feature-based stereo matcher, to generate a disparity map for a scene. Results are shown. An algorithm for stereo matching based upon 1D waveform matching is described. Techniques for generating a rigorous performance analysis to compare stereo matching algorithms on the basis of a manually derived 3D ground truth segmentation are discussed