A Comparative Study of Speckle Filtering In Polarimetric Radar SAR Images

Speckle appearing in polarimetric synthetic aperture radar (SAR) images is generated by coherent processing of radar signals. It hampers perception and extraction of fine details in the image. That is why speckle reducing is necessary before images analysis because Speckle filtering of polarimetric synthetic aperture radar (POLSAR) image has a great impact on the accuracy of terrain and land-use classification and scene interpretation. In this communication, we studied and tested several linear and non linear methods (Boxcar, Lee, Novak, Russell and Saad filters) to remove speckle in polarimetric SAR images. The single look complex (SLC) images to be filtered were acquired on the P band in airborne polarimetric mode. The evaluation of each filter is based on the following principal criteria: i) Its capacity to smooth the homogeneous areas, ii) Its aptitude to preserve contours, and iii) its capacity to preserve polarimetric information