Performance Analysis of SAR Image Speckle Filters and its Recent Challenges

Speckle noise is a critical disturbance in the Synthetic Aperture Radar (SAR) image that alters its quality. Initially, the speckle noise in SAR images should be reduced when recognizing and detecting automatic targets. This paper presents the performance analysis of different speckle filters which are applied in SAR images. The performance of individual filters to achieve speckle suppression and its ability to preserve image edges and details are analyzed. The performance analysis of some of the speckle and morphological filters are explored. Some of these filters result in small losses in the information on SAR images. It has also been found that the performance of these filters in the region of homogeneous area tends to increase with respect to the filter window size. Some of the morphological filters provide good performance in preserving the details of an image while suppressing the speckle noise compared to other adaptive filters. Finally, the recent challenges in speckle noise reduction filters are also explored.