Research On Next Generation Video Coding Technology Based On HEVC

In recent years,with the rapid development of Internet technology and the popularization of high-speed mobile Internet,digital video,one of the main representatives of the multimedia content,plays an increasingly important role in people's daily life and work.But the original digital video data is very large,which is difficult to store and transmit.Video coding technology can effectively compress original digital video data with little sacrifice on subjective quality of the original video to achieve efficient storage and fast transmission.High Efficiency Video Coding(HEVC)is the latest generation of video coding standard promulgated by international standards organization in June 2013.It achieves over50% coding efficiency gain comparing to the last generation video coding standard by utilizing a more flexible coding structure,expanding the size of coding units,increasing the number of coding modes and introducing new techniques.But it is foreseeable that as the video resolution increases,the storage space and network bandwidth are increasing,and the industrial community will have a higher demand for coding efficiency,so developing next-generation video coding standard to continuously improve coding efficiency has become a hot issue in academia.This thesis further explores how to optimize the standard algorithm to improve the coding efficiency,based on the detailed analysis of the HEVC framework and some main coding algorithms in HEVC,and puts forward three programs that can effectively improve the efficiency of video coding: firstly,on the basis of the deblocking filter of HEVC,the anomalous spike position caused by the filter is located by adding a judging step,and a corresponding algorithm is used to eliminate it;secondly,in the process of HEVC intra mode coding,the DC coefficients which account a high proportion in the bit stream are omitted,and those coefficients can be recovered by a texture based prediction algorithm using the decoded neighboring image blocks;thirdly,a new adaptive guided image filter is introduced in the HEVC in-loop process to sharpen the edge and texture.Experimental results show that the optimized deblocking filtering algorithm can better smooth the block boundary effect of the image,bringing about 0.50% coding gain and the DC coefficient prediction algorithm can effectively save about 1.38% biterate without lowering the image quality,and the adaptive guided image filter can effectively reserve the texture and edge information of the object in the video to improve the quality of the reconstructed image,which can also bring about 0.47% coding gain.