The Implementation And Optimization Of HEVC Encoding On Mobile Terminals

High efficiency video coding is the next generation video codec standard, which saves about 50% bitrates than H.264 in the same quality of videos. HEVC high compression ratio is at the expense of more complex recursive partition algorithm and longer encoding time. As the mainstream video codec standard, H.264/AVC makes great effort to meet user requirement. HEVC meets user demands for HD videos and brings new opportunities to develop in the future. New interactive broadcasting media project on the New Media product line promotes the integration of the traditional and new media. The project needs to provide higher resolution and smaller bitrates videos in the limited bandwidth of mobile devices. The research on HEVC is the requirement of the new media project and the forefront domain in the field of video codec. The paper presents the optimization results of the coding complexity and the process of transplanting the HEVC test mode to the mobile device.This paper describes the new codec technology which is adopted in HEVC and analyses the current research situation at home and abroad. A fast divided algorithm based on the statistics is proposed to reduce unnecessary sub-division and cut down the encoding complexity on the basis of the above research. The algorithm relays on the spatial correlation characters of the CUs. The algorithm decides whether to partition the sub-CU by comparing the sub-CU rate distortion value with the CU quarter.The experimental results show the encoding time saves about 24% in low complexity and 29% in high efficiency configuration compared with the reference software on the condition that the bitrates increase is no more than 2% and PSNR changes can be negligible. In order to make further optimization, a fast algorithm based on the statistics and variable coefficients is proposed. The increase of coding bitrates is about 1% and the encoding time saves about 24% and 25% in two configurations. In order to encode on mobile devices, the HEVC test mode and the optimization is transplanted to the mobile device. Mobile terminal experiment indicates: encoding time saves about 27% in two configurations under the condition that bitrates increase about 1%. Finally the research results are summarized, and the paper points the way for the next stage of the research and proposes the new request for the further optimization.