Despeckling of SAR Images via an Improved Anisotropic Diffusion Algorithm

Synthetic Aperture Radar (SAR) is a powerful tool for producing high-resolution images but these images are highly contaminated with speckle noise. This paper proposes an improved Anisotropic Diffusion Algorithm for despeckling SAR images. The proposed algorithm is obtained by using a diffusion coefficient which consists of a combination of first and second order derivative operators. The spatial variation of this diffusion coefficient occurs in such a way that it prefers forward diffusion to backward diffusion resulting in improved structural details and edge preservation. The simulation results also show better computational efficiency in comparison to other denoising techniques.

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