The Construction of Redundant Contourlet Transform and Its Application to SAR Image Despeckling
冗余轮廓波变换的构造及其在SAR图像降斑中的应用

The redundant contourlet transform implemented by undecimated pyramidal decomposition and directional filter bank is proposed. The circular symmetric filter bank satisfying perfect reconstruction conditions in the undecimated pyramidal decomposition is designed by McClellan transform. The adaptive local statistical model in the redundant contourlet domain and MAP estimator are employed to reduce speckle noise in SAR images. Compared with the despeckling methods based on stationary wavelet and contourlet transform, the proposed algorithm can reduce speckle noise more effectively while preserving the edges of the SAR images.