Low complexity depth intra coding combining fast intra mode and fast CU size decision in 3D-HEVC

3D-HEVC is the new coding standard dealing with both the texture and the associated depth video. In addition to some new coding tools designed for texture video with improved coding efficiency, some specified tools are devoted for depth video, such as depth modeling mode (DMM), segment-wise DC (SDC) mode and single depth intra mode. In this paper, we propose two techniques to speed up the encoding of depth video, including fast intra mode decision and fast CU size decision. For the fast intra mode decision, early termination is performed if the minimum rate-distortion (RD) cost of test candidate modes is smaller than the threshold computed from full mode search. For the fast CU size decision, smaller CU size will not be evaluated if the current CU presents some desired properties. The experimental results report that the proposed techniques achieve on average 37.6% time saving with 0.8% bitrate increase for the synthesized views under the all intra scenario.