Low complexity deblocking filter perceptual optimization for the HEVC codec

The compression efficiency of the state-of-art H.264/AVC video coding standard must be improved to accommodate the compression needs of high definition videos. To this end, ITU and MPEG started a new standardization project called High Efficiency Video Coding. The video codec under development still relies on trans form domain quantization and includes the same in-loop deblocking filter adopted in the H.264/AVC standard to reduce quantization blocking artifacts. This deblocking filter provides two offsets to vary the amount of filtering for each image area. This paper proposes a perceptual optimization of these offsets based on a quality metric able to quantify the blocking artifacts impact on the perceived video quality. The proposed optimization involves low computational complexity and provides quality improvements with respect to a non-perceptually optimized H.264/AVC deblocking filter. Moreover, the proposed optimization allows up to 92% of complexity reduction regarding a brute force perceptual optimization which exhaustively tests all the possible offsets values.