DSM generation from high resolution imagery: applications with WorldView-1 and Geoeye-1

In this paper we present and discuss some results obtained with a new proprietary matching strategy for DSMs generation, which is implemented in the SISAR software developed at the Area di Geodesia e Geomatica - Università di Roma "La Sapienza". In order to assess the accuracy of the new strategy, some tests were carried out, using a stereo pair of Augusta coastal zone (Sicily, South Italy) acquired from WorldView-1 and one of the first available GeoEye-1 stereo pairs, which was acquired over Rome. The results show that an accuracy at the level of about 2 m is achievable in open areas with both WorldWiew-1 and GeoEye-1 stereo pairs, whereas higher errors are displayed in urban areas. For WorldWiew-1 the results are still acceptable, being the accuracy at the level of 3 meters, but for GeoEye-1 the DSM extracted over a very dense urban area are much worse, with an accuracy at the level of 8-10 meters. Nonetheless, the new matching strategy has been proven effective, performing always better if compared with the one implemented in a well known and largely used software as PCI-Geomatics.