期刊名称:ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN:2194-9042
电子版ISSN:2194-9050
出版年度:2008
卷号:XXXVII Part B1
页码:117-122
出版社:Copernicus Publications
摘要:This paper introduces a wavelet transform speckle reduction algorithm for Synthetic Aperture Radar (SAR) imagery based on edge detection. Existing speckle algorithm can efficiently reduce the speckle effect but unfortunately also, to some degree, smear edges and blur images. In this paper, the original image is firstly logarithmic transformed and decomposed with multi-scale wavelet transform. For each pyramid level, edge cross points are detected by using the wavelet transform modulus maximum. The multi-scale and edge fusion strategy enables to detect only edge crossings and ignore the local oscillations. Then local wavelet soft-threshold filter is applied to the area that there is no edge crossing point. Repeat it through the image pyramid levels, and the despeckled image is reconstructed. The experiments have been carried out to verify the method proposed in this paper and the results is elaborately analyzed. The results have shown that our method can not only filter the speckle noise efficiently, but well preserve the image detail in the SAR imagery