Fast Depth Coding for Virtual View Synthesis in Real Time 3DV System

The synthesized result in depth based three-dimensional video system highly depends on the quality of the depth map. A fast depth map compression method oriented to virtual view rendering is proposed in order to speed up the compression of depth data while ensure the image quality of the synthesized virtual view. According to the characteristics of depth data and the impacts of depth distortion on virtual view synthesis, depth map is divided into edge regions and smooth regions, and correspondingly two search strategies are designed for the mode decision in depth map coding. Full search is for relatively complexity regions and edge regions, while SKIP, Inter 16×16 and all macroblock modes of Intra are for smooth regions and low complex regions. The experimental results evaluated by objective and subjective methods indicate that compared to X264, the proposed algorithm not only accelerates the depth map encoding greatly but also maintains considerable virtual view rendering quality with constant bit rate. It can be applied in real time depth based three-dimensional video system.