Performance improvement in HEVC using contrast sensitivity function

Abstract

High efficiency video coding (HEVC), the most recent video compression standard, offers about double the compression ratio over its immediate predecessor H.264/AVC at the same level of video quality or substantially higher video quality at the same bit-rate. Careful refinement of existing tools, as well as the introduction of a variety of parallel processing tools, helps the HEVC to attain the same. In HEVC, quantization is one of the key processes that decides the coding efficiency and the quality of the reconstructed video. Adaptive quantizers based on human visual system (HVS) models can be incorporated into the HEVC anchor model to improve the performance of the HEVC anchor. However, the major limitations of such schemes are the complexity involved. This paper presents an encoder, which uses a mathematical model of the contrast sensitivity function (CSF) to remove the visually insignificant information before the quantization without much impact on the visual quality of the video. The proposed method provides an average bit rate reduction of 2.75% for intra main configuration for a quantization parameter (QP) value of 22.