Bayesian-Based Speckle Suppression for SAR Image Using Contourlet Transform

摘要

A novel and efficient speckle noise reduction algorithm based on Bayesian contourlet shrinkage using contourlet transform is proposed. First, we show the sub-band decompositions of SAR images using contourlet transforms, which provides sparse representation at both spatial and directional resolutions. Then, a Bayesian contourlet shrinkage factor is applied to the decomposed data to estimate the best value for noise-free contourlet coefficients. Experimental results show that compared with conventional wavelet despeckling algorithm, the proposed algorithm can achieve an excellent balance between suppresses speckle effectively and preserves image details, and the significant information of original image like textures and contour details is well maintained.