DT-CWT Based Phase Preserving Algorithm for SAR Image Despeckling
基于双树复小波变换的相位保持SAR图像降噪

In this paper,a despeckling method is proposed for synthetic aperture radar(SAR) images.The method improves the phase preserving method using the non-orthogonal,complex valued,log-Gabor wavelets.Threshold of the wavelet responses in the complex domain ensures the important phase information in the image is not corrupted.The multiplicative and additive speckle noise components play an important role in SAR images,but sparately using the two models cannot result in satisfactory despeckling.The shift invariant dual tree complex wavelet transform(DT-CWT) is used which has an increased directional sensitivity. A wavelet-based image fusion method is developed based on the DT-CWT.Expected denoising performance is achieved through a well-chosen fusion scheme.Experimental results demonstrate that our method outperforms several other despeckling methods such as Frost filtering,Kuan filtering,Lee filtering and median filtering on the test images.