Acquisition of 3d Urban Models by Analysis of Aerial Images, Digital Surface Models and Existing 2d Building Information

For a task like 3D building reconstruction, there are three main data sources carrying information which i s required for a highly automated data acquisition. These data sources are aerial images, Digital Surface Models (DSM), which can either be derived by stereo matching from aerial images or be directly measured by scanning laser systems, and { at least for highly developed countries { existing (2D) GIS information on the ground plan or usage of buildings. The way these diierent data sources should be utilized by a process of 3D building reconstruction depends on the distinctive c haracteristics of the diierent, partly complementary type of information they contain. Image data contains much information, but just this complexity causes enormous problems for the automatic interpretation of this data type. The GIS as a secondary data source provides information on the 2D shape, i.e. the ground plan of a building, which i s v ery reliable, although information on the third dimension is missing and therefore has to be provided by other data sources. As the information of a DSM is restricted to surface geometry, the interpretation of this kind of data is easier compared to the interpretation of image data. Nevertheless, due to insuucient spatial resolution or quality o f t h e DSM, optimal results can o n l y b e a c hieved by the combination of all data sources. Within this paper two a p p r o a c hes aiming on the combination of aerial images, digital surface models and existing ground plans for the reconstruction of three-dimensional building reconstructions will be demonstrated.