Image denoising method based on adaptive anisotropic diffusion equation

When denoising with the method of Weickert's anisotropic diffusion equation, a lot of textures and details will be compromised during the process of denoising. Based on the defect, a fidelity term is added into Weickert's equation. The coefficient of fidelity term will vary adaptively with the contents of instant spatial position, which makes that the diffusion term and the fidelity term come to a better compromise. Otherwise, when deciding the edge directions, because of the strong smoothness of linear Gaussian function, a few other edge directions hiding in the main direction will be lost. To preserve these detailed edge directions, Gaussian kernel is substituted for nonlinear wavelet threshold. In addition, in order to realize the fact that different type of diffusion can be used in different position, the two eigenvalues are reset by combining the two methods: edge enhancing diffusion and coherence enhancing diffusion. Experiment results show that the new method has obvious effect in preserving textures and details.EI062261-2268