保持边缘的SAR图像滤波方法

Edge-preserving Filter for SAR Images

首先阐明了SAR图像边缘和边缘保持的概念。其次 ,提出了一种评价平滑图像边缘保持的方法。通过计算发现 ,常用的标准滤波方法 :增强Lee滤波、Kuan滤波、增强Frost滤波和GammaMAP滤波的边缘保持能力很差。最后发展了一种能保持边缘的SAR图像滤波方法。这种方法是对Han等人去除SAR图像斑点噪声方法的改进 。

This paper makes three contributions. It first clarifies the definition of edge and edge preservation in SAR images. The definition of edges preservation is important for edges preservation evaluation of digital speckle filters. Only the definition of edges preservation is reasonable, the edges preservation evaluation can be successfully performed. Second, an algorithm to evaluate edges preservation of digital speckle filters is proposed. Application of this algorithm to SAR images processed by Enhanced Lee, Enhanced Frost, Gamma, and Kuan has shown that these methods cannot effectively preserve edges. Third, the authors develop a new edge preserving speckle filters based on the method proposed by Han et al. and analyse the reason why the method proposed by Han et al. can effectively preserve edges in smoothed image.