Cooperation for analysis of maps and aerial images for urban scene description

In this paper we present a method to generate 3D cartographic databases in dense urban areas using simultaneously scanned maps and aerial images. The generation of digital terrain models (DTM) and the 3D description of buildings using aerial imagery are both supported by the previous analysis of scanned maps. Our approach relies on various information extracted form the maps on different features like the road network, the urban blocks and the buildings. These features are used to guide the analysis of a disparity image calculated with a stereo pair of aerial images. For the generation of a DTM, the road network allows to focus the algorithms on regions where the information on the ground elevation is available: the crossroads and the road sections. For the detection and the description of buildings, each urban block provided by the road network of the map is analyzed separately, taking into account the different features detected in the map. The effectiveness of this approach is demonstrated using complex imagery over large and dense urban areas presenting a large variety of landscapes.