Modified Value-and-Criterion Filters for Speckle Noise Reduction in SAR Images

Abstract

Speckle noise disturbance is the most essential factor that affects the quality and the visual appearance of the synthetic aperture radar (SAR) coherent images. For remote sensing systems, the initial step always involves a suitable method to reduce the effect of speckle noise. Several non-adaptive and adaptive filters have been proposed to enhance the noisy SAR images. In this paper, two proposed non-adaptive filters have been introduced. These proposed filters utilize traditional mean, median, root-mean square (RMS) values, and large size filter kernels to improve the SAR image appearance while maintaining image information. The performance of the proposed filters is compared with a number of non-adaptive filters to assess their ability to reduce speckle noise. For quantitative measurements, four metrics have been used to evaluate the performance of the proposed filters. From the experimental results, the proposed filters have achieved promising results for significantly suppressing speckle noise and preserving image information compared with other well-known filters.