Image Denoising with Wavelet Threshold Based on SURE Rule
Zhao Ruizhen · Journal of Beijing Jiaotong University · 2007
Based on the wavelet threshold denoising theory proposed by D.L.Donoho,a new threshold function is presented in this paper.It is rather similar to the hard threshold one,but it has two order continuous derivatives.Compared to soft threshold function,it can reserve image details much better due to its“hard”characteristic.Moreover,us two order deirvative makes it possible to construct an adaptive algorithm for image denoising.By using the new threshold function,a new adaptive shrinkage method is presented based on Stein's unbiased risk estimate(SURE).Two examples of Lenna and Bar- bara are given.The results indicate that the proposed method is very effective for image denoising ap- plication,in adaptively finding the optimal solution with least mean square error(LMSE)sense.