Non-Local SAR Image Despeckling Based on Similar Pixels Selected
Li Guang-ting①② Huang Ping-ping③ Yu Wei-dong①
①(Department of Space Microwave Remote Sensing System, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China) ②(Graduate University of the Chinese Academy of Sciences, Beijing 100049, China) ③(College of Information Engineering, Inner Mongolia University of Technology, Hohhot 010051, China)
Abstract Based on the ratio distance pixel-relativity and thresholding pixel-similarity, a modified non-local filter is proposed for SAR image despeckling in this paper. Firstly, the ratio distance pixel-relativity is obtained by transforming the joint probability density function of two pixels. Then, a table of pixel-similarity threshold, as a function of the SAR image look number and neighboring reflectivity ratio, is trained according to the minimum error probability. Finally, the pixel-similarity threshold is applied to select similar pixels from the searching window for the real reflectivity estimation. The proposed approach was verified by synthetic and real SAR images, and was compared with the PPB and LHRS-PRM filters. The visual quality and the quantification comparison show that the proposed approach is excellent not only in the reconstruction of the uniform area, the character of edges, texture, and details, but also with the lower computation complexity.
Li Guang-ting,Huang Ping-ping,Yu Wei-dong. Non-Local SAR Image Despeckling Based on Similar Pixels Selected[J]. JOURNAL OF RADARS, 2012, 1(2): 171-181.
2012, Vol. 1 
