Adaptive Blocking Artifacts Reduction Algorithm Based on DCT-Domain

Block-based DCT compression methods usually result in discontinuities called blocking artifacts at the boundaries of blocks due to the coarse quantization of the coefficients. In order to save more computations, an algorithm directly based on DCT-domain is proposed. It reduces the blocking artifacts as much as possible and preserve edge adequately as well. The algorithm presents a specific and convenient edge detection criterion. For the non-edge blocks, one-dimension DCT is used on each row of two adjacent blocks and the shifted block, and then the transform coefficients of the shifted block are replaced by adaptively weighted average of three blocks coefficients. For the edge blocks, Sigma filter is used to smooth the block boundaries. Simulation results show that the proposed reducing blocking artifacts algorithm outperforms the existing algorithms