Anisotropic diffusion filter without conductivity parameters

Two novel automatic anisotropic diffusion filters without conduction parameters were proposed in this paper. In the proposed first method, initially, the gradient of the noisy image to be filtered was calculated by Sobel operator and then the center of gravity of gradient image was used as diffusivity parameter, K and edge threshold. It was observed that the center of gravity of gradient image changed with noise. In the second approach, the complement of gradient image was directly employed as heat conductivity parameter in image filter. Consequently, the user dependency was avoided. The proposed image filter was tested with well-known test images.