Model based radiometric correction of optical imagery in mountainous regions for snow cover segmentation

Presents a model based technique for an efficient correction to topographically induced radiometric influences on remotely sensed imagery. In a first step, relief-induced geometric distortions are removed from optical imagery, taking terrain elevation into account. In a second step the radiometry is considered. Synthetic images are generated based on the digital elevation model, and Sun and satellite position at the time of acquisition of the image. The synthetically derived images model the image formation process for the directly lighted and shadow areas. Using direct, indirect and diffuse illumination. The resemblance of the synthesized image to reality is evaluated for a mountainous alpine region covered by snow. In a last step the derived image is used for the snow cover segmentation