Photogrammetric data capture and calculation for 3D city models

The 2D building data from the public Automated Real Estate Map (ALK) serve as a suitable basis for photogrammetric data capture for construction of large-area 3D city models. The following report provides an insight into the procedure for the measurement and calculation operations based primarily on the experience and requirements of the 3D city model in preparation for the state capitol of Stuttgart. This is a semi-automatic process, whose photogrammetric variables are generated analytically or digitally in 21/2D mode. Generation of the 3D model is accomplished exclusively with calculation programs in batch operation. The result is a high quality, digital 3D wire screen model for the data levels, terrain shape, buildings, structures and traffic areas. The fully renderable 3D city model is available in DXF format as well as an object-structured ASCII file.