ABSTRACT
Due to the high spatial resolution requirements for urban information systems, aerial photography has been used as standard imaging input. However, the advent of new satellites with a resolution of better than 1 m (e.g., IKONOS, Quickbird) and digital airborne scanners with excellent geometric fidelity and high spatial resolutions in the centimeter range (e.g., HRSC, ADS, DMC) challenges the analog airphoto techniques. These airborne and space-borne high-resolution sensors offer an advanced potential for generating and updating GIS databases, especially for urban areas. Moreover, digital airborne stereo sensors are capable of producing digital surface models (DSMs) by automated techniques. Coupled with differential GPS and inertial navigation systems (INS), these sensors generate georeferenced ultrahigh resolution multispectral image data together with their accompanying DSMs.
