View Synthesis Prediction in the 3-D Video Coding Extensions of AVC and HEVC
Advanced multiview video systems are able to generate intermediate viewpoints of a 3-D scene. To enable low-complexity free view generation, texture and its associated depth are used as input data for each viewpoint. To improve the coding efficiency of such content, view synthesis prediction (VSP) is proposed to further reduce interview redundancy in addition to traditional disparity compensated prediction. This paper describes and analyzes rate-distortion optimized VSP designs, which were adopted in the 3-D extensions of both Advanced Video Coding (AVC) and High Efficiency Video Coding (HEVC). In particular, we propose a novel backward-VSP scheme using a derived disparity vector, as well as efficient signalling methods in the context of AVC and HEVC. In addition, we put forward a novel depth-assisted motion vector prediction method to optimize the coding efficiency. A thorough analysis of coding performance is provided using different VSP schemes and configurations. Experimental results demonstrate average bit rate reductions of 2.5% and 1.2% in AVC and HEVC coding frameworks, respectively, with up to 23.1% bit rate reduction for dependent views.