Post-Filtering Of Transforms-Coded Images
Kou-Hu Tzou · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1988
An effective filtering technique has been introduced to reduce the blocking effect in transform-coded images. The proposed approach, employs circular-asymmetric two-dimensional (anisotropic) filters adapted to the characteristics of the blocking noise. By adaptively pointing the major axis of the anisotropic filters to the direction perpendicular to the orientation of the block boundary, the anisotropic filter can effectively reduce the block appearance while preserving the sharpness of the transform-coded pictures. Computer simulation of this new method shows significant improvement in image quality subjectively as well as objectively.