Spatial/temporal motion consistency based MERGE mode early decision for HEVC

A framework for the early decision of MERGE mode (EDM) is proposed to overcome the brute force inter mode decision for the coding unit (CU) in High Efficiency Video Coding (HEVC). Firstly, the prediction-results of merge candidates (MrgCands) in previous and current frame are modeled to identify smooth/single-motion regions for EDM. Secondly, the RD-cost based statistical model is proposed for EDM since MERGE is selected 98.20% on average when 2N×2N and MERGE produce similar RD-cost. Finally, a model is proposed that obtains the SAD values for the prediction units (PU) of modes using the motion-estimation of 2N×2N and performs EDM based on the comparison of these SAD values. Experimental results demonstrate that an average 46.75% coding time can be saved, while the Bjøntegaard delta bit rate (BDBR) increase is only 1.79%. In addition, an average of 68.54% complexity reduction is achieved with 1.79% BDBR increase for conference video sequences.