Research on Fast Merge Mode Decision Method for 3D-HEVC

High Efficiency Video Coding based 3D Video Coding (3D-HEVC) is a novel 3D video coding standard under research. In the test model of 3D-HEVC, due to the exhaustive checks of prediction modes for coding units (CU) derived from quad-tree partitioning structure, the mode decision process brings significantly high computational complexity. To reduce the complexity of mode decision, a fast merge mode decision method was proposed based on the high selection rate of merge mode in dependent texture views. For B frame, the correlation between coding modes of the current CU and inter-view reference blocks was analyzed. For P frame, the correlation between coding modes of CUs located in adjacent depth levels was analyzed. Based on the correlations, conditions of fast merge mode decision and fast skip mode decision were designed. When the conditions were satisfied, merge mode coded CUs and skip mode coded CUs were early determined. For the early determined CUs, only relevant candidate prediction modes were checked and other prediction modes were skipped to reduce computational complexity. Experimental results show that average 11.2% of total encoding time saving and 25.4% of encoding time saving for dependent texture views can be achieved with negligible rate distortion performance loss compared with the original method in 3D-HEVC.