一种用于合成孔径雷达图像相干斑抑制的双边滤波参数配置新方法

A novel method to configure the parameters of the bilateral filtering for synthetic aperture radar images speckle reduction

基于最优折衷假设以及等效视数曲线和边缘保持指数曲线的单调特性,提出了一种用于合成孔径雷达(SAR)图像相干斑抑制的双边滤波参数配置新方法.该方法与传统方法相比,在计算时间相当的情况下,灰度值近似方差精度提高一个数量级;当灰度值近似方差精度相同时,计算时间减少一个数量级.

Bilateral filtering can effectively smooth SAR images with the edges preserved,but it is difficult to optimally configure the parameters of bilateral filtering.Traditional method is based on an optimal trade-off hypothesis according to the despeckling estimation indexes,including the equivalent number of looks（ENL） and edge preserving index（EPI）.However,the variance of gray value similarity obtained by traditional method has large error,and to improve accuracy,the computing time is increased linearly.In this paper, we present a novel method to configure the parameters of bilateral filtering based on the hypothesis and the monotone properties of the ENL and EPI curves.Experimental results show that the accuracy of variance of gray value similarity is increased by one order of magnitude in the case of almost the same computing time;the computing time is reduced by one order of magnitude for the same accuracy of variance of gray value similarity.