A Novel Directionlet Based Image Denoising Method Using MMSE Estimator and Lapla

A novel method based on directionlet transform is proposed for image denoising under Bayesian framework. In order to achieve noise removal, the directionlet coefcients of the uncorrupted image are modeled independently and identically by a two-state Laplacian mixture model with zero mean. Te expectation-maximization algorithm is used to estimate the parameters that characterize the assumed prior model. Within the framework of Bayesian theory, the directionlet coefcients of noise-free image are e