VLSI Implementation of HEVC Motion Compensation With Distance Biased Direct Cache Mapping for 8K UHDTV Applications

Shihao Wang, Dajiang Zhou, Jian-Bin Zhou, Takeshi Yoshimura, Satoshi Goto

Abstract: Ultrahigh definition television is becoming increasingly attractive and practical with the doubled compression performance delivered by High Efficiency Video Coding (H.265/HEVC). Meanwhile, implementation of real-time video codecs is challenged by not only the huge throughput and memory bandwidth requirements but also the increased complexity of new algorithms. For motion compensation (MC) that is a known bottleneck in video decoding, the enlarged and diversified prediction unit sizes impose notably higher difficulties in trading off area, power, and memory traffic. This paper presents a very large scale integration implementation of HEVC MC that supports 7680 × 4320@60 frames/s bidirectional prediction. The MC design incorporates a highly efficient cache realized by novel architecture optimizations including distance biased directing mapping, eight-bank memory structure, row-based miss information compression, and mask-based block conflict checking. As a result, the proposed design not only achieves 8× throughput enhancement but also improves hardware efficiency by at least 2.01 times, in comparison with prior arts.