Patent ID: 7277590

Claim:
An image processing method for conducting anisotropic diffusion filtering on a pixel value I i,j in a two-dimensional image, comprising the steps of: finding conduction coefficients C n , C s , C w , C e , C nw , C sw , C ne and C se in eight surrounding directions for each pixel based on a pixel value gradient ∇I to produce a two-dimensional distribution image of the conduction coefficients; and finding pixel value first partial differentials ∇ n I, ∇ s I, ∇ w I, ∇ e I, ∇ nw I, ∇ sw I, ∇ ne I and ∇ se I in the eight surrounding directions for each pixel to calculate a pixel value in an output image according to: I i , j n + 1 = ⁢ I i , j m + ⁢ λ [ [ C n · ∇ n ⁢ I + C s · ∇ s ⁢ I + C w · ∇ w ⁢ I + C e · ∇ e ⁢ I ] + ⁢ 1 2 ⁡ [ C nw · ∇ nw ⁢ I + C sw · ∇ sw ⁢ I + C ne · ∇ ne ⁢ I + C nw · ∇ nw ⁢ I ] ] i , j n , (n: the number of times of repetition, λ: a constant).