Performance analysis of DEM automatic extraction from SPOT5 sensors

During the first six months following the successful SPOT5 launch, the capabilities of its various sensors for topographic applications have been widely tested. This paper summarizes the extensive experiments we made with SPOT5 high resolution sensors in the domain of automatic terrain extraction. Correlation based Digital Elevation Models were produced from along the track HRS and cross track HRG stereo pairs. In the case of HRG, different modes and stereo angles have been evaluated. The results have been compared to a high resolution reference DEM covering the whole swath of the HRS images. The experiments have been made with and without using ground control points. The analysis shows the improvement that could be expected, respectively, from resolution enhancement, almost simultaneous stereoscopy and better attitudes estimates, compared to the previous SPOT satellite generation.