A NOVEL 3D CITY MODELLING APPROACH FOR SATELLITE STEREO DATA USING 3D ACTIVE SHAPE MODELS ON DSMS
Since remote sensing provides new sensors and techniques to accumulate stereo data on urban regions, three-dimensional (3D) repre- sentation of these regions gained much interest for various applications. 3D urban region representation can e.g. be used for detailed urban monitoring, change and damage detection purposes. In order to obtain 3D representation, one of the easiest and cheapest way is to use Digital Surface Models (DSMs) which are generated from very high resolution stereo satellite images using stereovision tech- niques. Unfortunately after applying the DSM generation process, we cannot directly obtain a full 3D urban region representation. In the DSM which is generated using only one stereo image pair, generally noise, matching errors, and uncertainties on building wall loca- tions are very high. These undesirable effects prevents a DSM to provide a realistic 3D city representation. Therefore, some automatic techniques should be applied to obtain real 3D city models using DSMs as input. In order to bring a solution to the existing problems in this field, herein we propose a fully automated approach based on the usage of a novel 3D active shape model. Our experimental results on DSMs of Munich city which are obtained from different satellite (Cartosat-1, Ikonos, WorldView-2) and airborne sensors (3K camera, HRSC, and LIDAR) indicate possible usage of the algorithm to obtain 3D city representation results automatically.