Ringing reduction in image restoration by orientation-selective regularization

The success of ringing artifact reduction in image restoration depends mainly on how the restoration methods accommodate the piecewise smoothness of the image. The article presents a regularization method that adapts both its degree and orientation of regularization operation to the spatial activities of the image intensity and edge orientations. This is achieved by anisotropic diffusion. Its restoration quality compares favorably with that of a previously proposed regularization method that is space adaptive only in the degree of regularization.