Towards Perceptually Guided Rate-Distortion Optimization For Hevc

This paper proposes a novel approach for perceptually guiding the rate-distortion optimization (RDO) process within the High Efficiency Video Coding (HEVC) standard. The reference codec does not consider effectively the perceptual characteristics of the input video and further, the particular perceptual sensitivity of each coding tree unit (CTU) inside a frame. The corresponding frame-level Lagrangian multiplier depends only on the quantization parameter. Inspired by the mechanisms of the human visual system, the proposed solution is a CTU-Ievel adjustment of the standard Lagrangian value based on a set of complementary measured features. These measures rely on the spatial and temporal analysis of the current CTU in the frequency domain. Based on perceptual quality indices and Bjontegaard delta measurements, over several resolutions of tested video sequences, the proposed method demonstrates a promising coding performance according to the rate-distortion compromise.