Neighboring block based disparity vector derivation for 3D-AVC

3D-AVC, being developed under Joint Collaborative Team on 3D Video Coding (JCT-3V), significantly outperforms the Multiview Video Coding plus Depth (MVC+D) which has no new macroblock level coding tools compared to Multiview video coding extension of H.264/AVC (MVC). However, for multiview compatible configuration, i.e., when texture views are decoded without accessing depth information, the performance of the current 3D-AVC is only marginally better than MVC+D. The problem is caused by the lack of disparity vectors which can be obtained only from the coded depth views in 3D-AVC. In this paper, a disparity vector derivation method is proposed by using the motion information of neighboring blocks and applied along with existing coding tools in 3D-AVC. The proposed method improves 3D-AVC in the multiview compatible mode substantially, resulting in about 20% bitrate reduction for texture coding. When enabling the so-called view synthesis prediction to further refine the disparity vectors, the performance of the proposed method is 31% better than MVC+D and even better than 3D-AVC under the best performing 3D-AVC configuration.