ASIC Solution for the Directional Intra Prediction of the AV1 Encoder Targeting UHD 4K Videos

AOMedia Video 1 (AV1), developed by the Alliance for Open Media consortium and released in 2018, is an open-source and royalty-free video format. It was designed to deliver substantial compression gains over its predecessor VP9 whilst keeping hardware feasibility and a practical decoding complexity. When compared to state-of-the-art formats, AV1 has more complex encoder tools, including the intra prediction which is the focus of this work. This paper presents a highly parallelized ASIC solution for the directional intra prediction module. It supports all 56 directional modes defined in AV1 and is able to process all combinations of block partitions. When synthesized to the TSMC 40nm technology with a target frequency of 1,296MHz, the proposed design used an area of 455.8K gates and showed a power dissipation and energy consumption per predicted sample of 40.92mW and 0.055pJ/sample, respectively. The reached throughput supports the processing of 60 frames per second for UHD 4K videos (3840×2160 pixels). No other work was found in the literature with a hardware design supporting the AV1 intra prediction directional modes.