A 249Mpixel/s HEVC video-decoder chip for Quad Full HD applications

Abstract

The latest video coding standard High Efficiency Video Coding (HEVC) provides 50% improvement in coding efficiency compared to H.264/AVC, to meet the rising demand for video streaming, better video quality and higher resolutions. The coding gain is achieved using more complex tools such as larger and variable-size coding units (CU) in a hierarchical structure, larger transforms and longer interpolation filters. This paper presents an integrated circuit which supports Quad Full HD (QFHD, 3840×2160) video decoding for the HEVC draft standard. It addresses new design challenges for HEVC (“H.265”) with three primary contributions: 1) a system pipelining scheme which adapts to the variable-size largest coding unit (LCU) and provides a two-stage sub-pipeline for memory optimization; 2) unified processing engines to address the hierarchical coding structure and many prediction and transform block sizes in area-efficient ways; 3) a motion compensation (MC) cache which reduces DRAM bandwidth for the LCU and meets the high throughput requirements which are due to the long filters.