A Gamma Distribution-Based Fuzzy Clustering Approach for Large Area SAR Image Segmentation

Xuemei Zhao, Haijian Wang, Jun Wu, Zhiyong Peng, Xiaoli Li

Abstract: Synthetic aperture radar (SAR) image segmentation is a challenge due to its inherent speckle. Gamma distribution is believed to be an appropriate statistical model to describe the characteristics of speckle in SAR images. In this letter, a fuzzy clustering algorithm based on gamma distribution for SAR image segmentation is proposed, in which the Stirling equation is used to approach the gamma function in the dominator of gamma distribution under the assumption of mean field theory to make the shape parameter $\alpha $ derivable. Then, the value range of the estimated $\alpha $ is demonstrated to meet the requirement of gamma distribution by Jensen’s inequality. Experimental results show that the proposed method gives promising results in SAR image (including large area SAR image) segmentation and effectively suppresses the influence of speckle.