A 5.3 Gpixels/s Frame Memory Recompression Method for QHD Video Coding

摘要

4K (3840×2160) and 8K (7680×4320) formats video applications enhance visual experience, however, at the expense of much more complicated video encoder needed. High-Efficiency Video Coding(HEVC) standard is a new video compression standard which can double the compression ratio with respect to the previous H.264/AVC standard at the same level of video quality. H.265/HEVC adopts the quad-tree coding structure, leading to serious design problems, such as high computational complexity, high energy consumption and huge external memory bandwidth requirement. Frame memory recompression is an efficient way to reduce both system power and external memory traffic. This work emphasizes the hardware implementation of a high-throughput reference frame recompression scheme. Compared to no compression, the proposed algorithm can reach an average lossless compression rate of 51.0% for evaluated video sequences. The hardware architecture is implemented with 29.5k gates for the compressor and 14.4k gates for the decompressor at 500MHz using TSMC 65nm CMOS standard-cell libraries. The throughput of this architecture is 5.3 Gpixels/s under 4:2:0 sampling, which is able to process Quad High Definition (QHD) at 60 fps.