Abstract
Images issued from a SAR (Synthetic Aperture Radar) sensor are effected by a specific noise called speckle;
therefore, many studies have been dedicated to modulate this noise with the aim to be able to reduce its
effects. But, studies in the area of polarimetric SAR (PolSAR) images despeckling are still poor and don't take
advantage correctly of polarimetric information. In this way, this paper describes an original and efficient method
of despeckling PolSAR images in order to improve the visualization and the extraction of planimetric features.
The proposed filter, takes into account all polarization modes for each polarization mode despeckling. So, for a
pixel in a single polarization mode, the modification of its radiometric value will be supervised by it adjacent
pixels in the same polarization mode and also by their equivalent pixels in other polarization modes. Furthermore,
to avoid error propagation, the filter will be very cautious in modification of radiometric values in such way that
it runs in many iterations modifying the less ambiguous pixels firstly and leaves the rest of the pixels for the
next iterations for a possible modification. To combine the information resulting from each polarization mode
and make a decision, the proposed filter calls some rules of the Evidence Theory. The experimentation was done
on Radarsat-2 images of the Arctic and Quebec regions of Canada, and the results show clearly the benefit and
the high performance of this despeckling approach.
