Unsupervised multiscale speckle filtering

In this paper a new speckle filter for SAR images is proposed, based on a wavelet decomposition. The N-levels decomposition of the initial image with a filter bank provides high frequency images containing wavelet coefficients and low frequency images. This analysis tool allows us to separate details, edges, ... from low frequency information (intensity averages). High frequency images are treated specifically in order to keep only significant wavelet coefficients. An adaptive filter is applied on the low frequency images during the reconstruction stage so as to eliminate the residual speckle.