关键词: 各向异性扩散滤波, 多方向中值滤波, 扩散系数, 局部方差, 图像梯度

Abstract: This paper proposes an algorithm improved by anisotropic diffusion filtering. Existing research methods have many problems, such as unclear with the image edge, also there is a plenty of false recognition and it is usually a subjective choice to the diffusion coefficient. The algorithm uses Median Filtering Method in multi directions of diffusion which can retain the edge and the details. Improve the diffusion coefficient by using local variance and image gradient and modify the diffusion coefficient by multiple iterations, and this can enhance the robustness of the algorithm. The algorithm can de-noise and retain the edges and the details. By several simulation experiments, compared the simulation results with the peak signal noise ratio, the mean square error, the structure similarity and the figure of merit as four quantitative indicators. It shows that the algorithm has great ability on de-noise and retain image edges than the traditional anisotropic diffusion method and Catt _PM model.

Key words: anisotropic diffusion filtering, median filtering method in multi directions, diffusion coefficient, local variance, image gradient