STEREO IMAGE MATCHING STRATEGIES: IMPLEMENTATION OF ALGORITHMS BASED ON CORNER DETECTION AND DYNAMIC PROGRAMMING

An important products obtained from high resolution satellite stereopairs are Digital Surface Models (DSMs). Thanks to the very high resolution and the good radiometric quality of the images, it seems possible to extract a DSM comparable to middle scale aerial products. The accuracy level of DSM is strictly related both to the image orientation and to the matching process . In the last year a facility for the image matching has been included in the SISAR software, which is a scientific program suitable for the high resolution image orientation, developed at the Geodesy and Geomatic Area - University of Rome “La Sapienza”. The SISAR image matching facility is based on two different algorithms: a combination of Area Based Matching (ABM) and the Feature Based Matching (FBM) and a two-stage dynamic programming technique. In order to assess the accuracy of the two algorithms many tests were carried out, using a stereo pair acquired from WorldView-1 for first algorithm and a stereo pair with quasi-epipolar geometry acquired by GeoEye-1 for the second one; as reference data, a DSM obtained from LiDAR surveys and from a 3D vector cartography at 1:2000 scale have been employed respectively.