An Edge-enhanced Modified Lee Filter for the Smoothing of Sar Image Speckle Noise
نویسنده
چکیده
One problem in processing Synthetic Aperture Radar (SAR) images is the presence of speckle noise which is multiplicative in the sense that the noise level increases with the magnitude of radar backscattering. In this paper, an edge-enhanced ltering method is presented which is based on a ratio-based edge detector used in conjunction with an iterative application of a modi ed Lee lter. Test results obtained by applying this method to synthetic images corrupted by SAR speckle show that the edge-enhanced modi ed Lee lter has the ability to remove speckle in both low and high variance regions while retaining the sharpness of edges even after several iterations. As such, this ltering method may be useful in SAR image segmentation and classi cation applications.
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