Depth Map Coding for View Synthesis Based on Distortion Analyses

In 3-D video, view synthesis with depth-image-based rendering is employed to generate any virtual view between available camera views. Distortions in depth map induce geometry changes in the virtual views, and thus degrade the performance of view synthesis. This paper proposes a depth map coding method to improve the performance of view synthesis based on distortion analyses. The major technical innovation of this paper is to formulate maximum tolerable depth distortion (MTDD) and depth disocclusion mask (DDM), since such depth sensitivity for view synthesis and inter-view redundancy can be well utilized in coding. To be more specific, we define two different encoders (e.g., base encoder and side encoder) for depth maps in left and right views, respectively. For base encoding, different types of coding units are extracted based on the distribution of MTDD and assigned with different quantitative parameters for coding. For side encoding, a warped-SKIP mode is designed to remove inter-view redundancy based on the distribution of DDM. The experimental results show that the proposed scheme not only achieves high view synthesis performance, but also reduce the computational complexity of encoding.