Image denoising is an important issue of image processing as the degraded image can cause a lot of limitations for further application. Mathematically, image denoising is an inverse problem, and it will be an ill-posed inverse problem if there is a blur kernel. At present the most important and effective way of solving inverse problem is regularization method. The main idea of regularization method is that take regularization operator as the approximation of the original ill-posed operator, the regularizati...