Research In Fast Mode Decision Algorithm Of HEVC

:As people pursue high quality of the visual and auditory, the requirements of the existing video compression standard is more and more higher. The latest High Efficiency Video Coding (HEVC) video coding standard version offers50%bit rate reduction against the H.264/AVC at the same visual quality. However, HEVC encoder complexity, especially in the part of intra prediction and inter prediction, is tremendously increased. It is therefore important to develop efficient encoding algorithms for the success of HEVC based applications.In order to reduce the algorithm complexity of HEVC video coding, this thesis firstly studies the HEVC video coding and its key technology, then an in-depth study on Intra prediction and Inter prediction algorithm of HEVC video coding. Based on the analysis of their algorithms complexity, we propose a priority classification based fast mode decision for speed up the HEVC encoder. Each prediction unit (PU) is given a priority label out of four based on its spatial and temporal neighbor PU information as well as the predicted PU depth. Different processing strategy will be applied to different priority class, under the assumption that more computing resource should be allocated to the high priority class since its corresponding PU has the high potential to be chosen as the optima.Experiments are performed using all the common test sequences, and results show that, the encoder complexity is significantly reduced by about46%for All Intra configuration with BD-Rate (Bjontegaard Delta bit rate) increase less than0.9%for luma component. Meanwhile, compared with several recent works, our proposed solution demonstrates the well trade-off between the coding efficiency and complexity reduction. For Inter configuration, the algorithm can save an average of38%encoding time with only1.44%of BD-Rate loss. The experimental results indicate that the algorithm of priority classification can reduce the complexity of HEVC encoder and greatly improved the performance and feasibility of HEVC.