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SAR Speckle Reduction Based on Nonlocal Means Method

Synthetic aperture radar (SAR) images are inherently affected by speckle noise, which is due to the coherent nature of the scattering phenomenon. This paper presents a novel SAR speckle reduction method base on nonlocal means (NLM) filter. NLM is applied to remove additive noise after taking the logarithm of the original speckle noise. The proposed method can preserve edges and protect more fine details. Results on real speckle SAR images are given. We have also compared our method with some related methods.