Speckle Denoising of the Multipolarization Images by Hybrid Filters

Abstract

Speckle reduction in synthetic aperture radar (SAR) images and SAR polarimetry (PolSAR) is important for the extraction of important information for homogeneous extended areas. Finding good balance between spatial detail preservation and high equivalent number of looks is a challenge. In this paper, we validate the use of the infinite number of looks filter (INLP) method for the denoising of the multipolarization channels (i. e. hh, hv and vv) by representing their analogy with the eingenvalues of the coherency matrix. The denoised pixels obtained by a traditional filtering method served as inputs for the INLP method. Results demonstrated that the proposed method outperformed traditional filters i. e. boxcar and the refined sigma filter in terms of spatial detail preserving and speckle reduction.