A new approach for restoring block-transform coded images with estimation of correlation matrices

This paper presents a new restoration approach to reduce coding artifacts in block-transform image coding. Different from conventional restoration techniques, the proposed one is non-iterative and requires a low computational cost, yet can reconstruct objectively and subjectively better images. This good performance is achieved because of the following advantages the proposed approach has: (i) efficient incorporation of the solution bound into restoration; and (ii) effective exploitation of local image properties and statistical knowledge about the quantizers used