Polarimetric radar image despeckling by iteratively refined nonlocal means

doi:10.11947/j.AGCS.2019.20180034

Abstract

Abstract: The presence of speckle degrades the quality of the polarimetric synthetic aperture radar (PolSAR) image, hence despeckling is an essential procedure before using SAR images to obtain land-cover information in most cases. In this paper, a PolSAR filtering method based on iteratively refined nonlocal means is presented. In each iteration step of the proposed method, by considering both the statistical trait of the original image and the information of the image obtained in last iteration, the polarimetric similarity between pixels is refined, so as to improve the estimation results. Experiments on a simulated PolSAR image and two real PolSAR images revealed the positive despeckling performances of our proposed method:the speckle is reduced to a large degree, and the image details, such as the edges and the polarimetric traits, are effectively preserved.

Key words: polarimetric synthetic aperture radar, speckle filtering, nonlocal means, likelihood-ratio test

CLC Number:

P237

MA Xiaoshuang, WU Penghai. Polarimetric radar image despeckling by iteratively refined nonlocal means[J]. Acta Geodaetica et Cartographica Sinica, 2019, 48(8): 1038-1045.

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