Automated Generation and Updating of Digital City Models Using High-resolution Line Scanning Systems

During the past few years lots of research has been carried out in the field of building extraction from airborne laser scanner data and airborne large-scale imagery. This data can be used to create highly detailed Digital Surface Models (DSMs) and eventually Digital City Models (DCMs). It seems that there exists also a potential in data acquired by high-resolution satellites and airborne multi-line scanners in order to derive these models. Already existing extraction-algorithms for Lidar data cannot be adopted to those spaceborne and airborne imageries since the geometric resolution is too coarse. The proposed method can be divided into the following steps. The derived normalized DSM is used together with image data to localize potential building areas. Afterwards the building edges and corners are extracted, which is carried out with an adaptive region growing process and an iterative step-by-step Hough transformation. Finally, change detection techniques and a method for updating existing data-bases in an automated way are discussed.