Study On Fast Mode Selection Algorithm For The Next Generation Video Coding Standard Hevc

High Efficiency Video Coding (HEVC) is a next generation standard that is developed jointly by International Telecommunication Union-Telecommunication Standardization (ITU-T) and International Organization for Standardization and International Electro Technical Commission (ISO/IEC) which regarded as the most famous video coding standard developers. HEVC reserved the framework of traditional video coding and adopted the newest technology in recent years about video coding field. As a result, the performance is two times as the H.264/AVC standard, and it applied not only in high-definition video but also in more widely field. However, the improvement of compression performance sacrificed the time performance. Based on former problem, this thesis studied on the fast mode selection algorithms with expecting to decrease the coding time.Firstly, In order to decrease the complexity of coding, we deeply researched and analyzed the HEVC’s core technology, specially the mode selection and the modules that could influence the performance of mode selection. Secondly, we went through the fast mode selection algorithms on H.264/AVC, analyzed and studied rare papers related with fast mode selection on HEVC. Finally, we borrowed ideas from H.264/AVC’s fast mode selection algorithms, proposed fast mode selection algorithms for HEVC.Initially, this thesis studied on intra mode and proposed two algorithms; one is fast mode selection based on prediction unit edge grain direction detection, and the other is spatial-based fast mode selection algorithm. The former adopted edge direction detection technology to reduce intra modes’ candidate and the simulation result shows that this method can save the encoding time by16%on average, the latter adopted spatial adjacent coding unit similarity quickly determining the level of the coding unit and prediction direction, the simulation result indicates that this method saves the encoding time by28%. Secondly, we studied on HEVC inter mode and inter fast mode selection on H.264/AVC, then proposed adaptive Skip mode fast selection algorithm and coding unit quick determination algorithm. The former algorithm adopted the characteristic of cost distribution concentration of Skip mode which could adaptively adjust Skip cost mean and regard it as the threshold to determine Skip mode in advance, the simulation result indicates that this method saves encoding time by56.98%. The latter algorithm was applied in scenario of B images coding, it borrowed ideas from the regularity that the deeper time-domain level the more large coding unit number, the simulation result indicates that this method saves coding time47.64%.