CityGML – OGC Standard for Photogrammetry?

Virtual 3D city models are an important data source for an increasing number of applications. Today, most 3D city models are created using data and methods from photogrammetry, remote sensing, and surveying. New applications of 3D city models require additional information about the city objects besides geometry and radiometry. Especially the ontological structure including thematic classes, attributes, and their interrelationships has to be represented and reconstructed. This means that photogrammetric software systems will have to be able to generate and handle more complex models as in the past. Since complex geodata products like cadastre objects or 3D city models are seldom produced in one step, additionally an appropriate data exchange format is required that avoids information loss during the processing chain starting from initial geometry registration, leading over semantic qualification and finally to the end-user applications. In this paper we discuss the requirements along the processing chain in detail and raise the question to which extent CityGML, the new international standard of the Open Geospatial Consortium for the representation and exchange of virtual 3D city models, can support the manual and automated steps for the acquisition of 3D city models.