Computationally efficient HEVC/H.265 motion estimation algorithm for low power applications

High Efficiency Video Coding (HEVC/H.265) is an emerging standard for video compression that provides almost double compression efficiency at the cost of major computational complexity increase as compared to current industry-standard Advanced Video Coding (AVC/H.264). In HEVC more flexible coding options and partitioning types are provided for prediction units (PUs) and consequently motion estimation (ME) is more involved than previous video-coding standards. The existing fast ME algorithms, including the test zone search provided in the HEVC reference software, cannot generate high-quality video with reasonable computational complexity. In this paper, four algorithms are proposed and designed for optimizing the motion estimation process for the H.265/HEVC whilst maintaining the same quality and the compression rate as the standard. The conducted experiments show significant speed improvements, thus making a novel contribution to the implementation of realtime H.265 standard encoders in computationally constrained environments such as low-power mobile devices and general purpose computers.