3D Information extraction by structural matching of SAR and optical features

The subject of this paper is the extraction of 3D information using an optical image and a SAR image. This aim is made difficult by the very different appearances of the landscape and the man-made features in both images. The proposed method is based on the extraction of SAR primitives (bright linear and point features). They are then matched to the optical image using the directional and modulus gradient map computed on the optical image. A set of matches and associated heights is selected for each primitive. In a first step, the digital terrain model is computed in an iterative way around the predominant height of the SAR primitives. In a second step, using the external knowledge of a building map, the mean height of each building is computed by means of the previous DTM and the remaining matching primitives. The results obtained on an industrial test area are evaluated.