SPECKLE NOISE REDUCTION FOR SAR IMAGES USING INTERSCALE MULTIPLICATION AND SOFT THRESHOLDING

This paper presents a technique for speckle reduction in SAR images by using the interscale multiplication in Mallat wavelet transform (MWT) and stationary wavelet transform (SWT). The edge and non-edge regions can be detected from median of squared amplitude in each scale. Applying this technique, the large wavelet coefficients generated by edge region and the small wavelet coefficients or speckle noises are then suppressed by using soft thresholding in all high frequency hands. The well-known threshold estimation for soft thresholding based on SimpleShrink, NormalShrink, VisuShrink, SureShrink, and BayesShrink. The despeckled image is then obtained by reconstruction from the resulted coefficients. The assessment of the proposed method, the experiment has conducted using SAR images from JERS-1 satellite. The experimental result shows that the proposed method yields noise suppression and preserves the detail feature of the images, as well as perceptual image quality.