Heuristic-Based Algorithms for Low-Complexity AV1 Intraprediction

Abstract

Modern video encoders, such as the state-of-the-art AOMedia Video 1 (AV1) and Versatile Video Coding (VVC), offer significant compression gains at the cost of an increase in computational effort. This is partially because of the novel intra prediction techniques, including an increased number of prediction modes and block sizes supported by the codecs. To reduce this computational effort, this work proposes two heuristic-based algorithms for AV1 intra prediction: a fast mode decision that reduces the number of intra candidates with a low-cost direction detection method, and a mode-adaptive subsampling algorithm that significantly reduces the number of Sum of Squared Errors (SSE) operations after prediction. On average, a notable encoding time reduction of 29.8% was achieved, at the cost of a compression efficiency loss of 1.28%.