Using multisource databases for automated identification of control points on RADARSAT images

The users of RADARSAT images need ground control points (GCPs) to geometrically correct or to match the images. But the selection of GCPs has been done manually until now. Thus, the quality of the rectified images depends on the ability of the operator to select high quality GCPs. This selection is more dif- ficult in SAR images due to their particular geometry and radiometry. We worked on the development of a method and software to automatically identify high quality GCPs in RADARSAT images using data from a topographic database. Different strategies have been elaborated to fit with different contexts. These strategies are gathered into two approaches used to match the two data sources: the vector and the raster approach. Fo r both approach, a method has been developed to automatically identify GCPs from the category "stretches of water". A GCP software prototype has also been implemented according to these methods.