A multi step approach to rectify radar images geometrically and radiometrically is presented. The method uses digital elevation models (DEMs) and an image simulator to establish the relation between radar image coordinates and ortho image locations. The simulation serves to create a synthetic gray value image similar in its geometry to the real radar image, associating with each image pixel a backscatter value dependent on the incidence angle and a DEM address. Correlation between simulated and real and real image results in a relation between radar backscatter values and DEM addresses and produces an ortho image in an additional step. Stereo derived and map derived elevation models were used to demonstrate the rectification process for air and spaceborne radar images.
|Publisher||Inst. für Digitale Bildverarbeitung und Graphik|