Adaptative ranked-order vectorial speckle filtering in polarimetric SAR images : Comparaison with a class of filters

摘要

Speckle appearing in synthetic aperture radar (SAR) images is generated by coherent processing of radar signals . It hampersudperception and extraction of fine details in the image . That is why speckle reducing is necessary before images analysis .udIn this paper, we have studied and tested several linear and non linear vectorial methods (Novak, Lee, Russell) to remove speckle inudSAR images. Russell's method has proved its efficiency and simplicity of implementation, it is not adaptive . So we have generalizedudRussell's method to make it adaptive by pixel . Adaptivity is based on the generalization of local scalar variation towards a caseudof a vectorial variation, on one hand, and on local and global statistic analysis of the latter, on the other hand .udTo evaluate the performance of a filtering method, we propose criteria that join the two qualities, smoothing and edge preservation .udA comparative study with several vectorial filtering methods show that the proposed method provides the best results according toudthe proposed criteria.