文献类型：期刊文献

英文题名：String Prediction for 4:2:0 Format Screen Content Coding and Its Implementation in AVS3

作者：Zhou, Qingyang[1];Zhao, Liping[2];Zhou, Kailun[1];Lin, Tao[1];Wang, Huihui[1];Wang, Shuhui[1];Jiao, Mengcao[1]

机构：[1]Tongji Univ, Coll Elect & Informat Engn, VLSI Lab, Shanghai 200092, Peoples R China;[2]Shaoxing Univ, Dept Comp Sci & Engn, Shaoxing 312000, Peoples R China

年份：2021

卷号：23

起止页码：3867

外文期刊名：IEEE TRANSACTIONS ON MULTIMEDIA

收录：SCI-EXPANDED(收录号：WOS:000709093100034)、、EI(收录号：20214411099907)、Scopus(收录号：2-s2.0-85118210867)、WOS

基金：This work was supported in part by the Natural Science Foundation of Zhejiang Province under Grant LY19F020015, in part by the National Science Foundation of China under Grant 61871289, in part by the Public Service Technology Application Research Project of Shaoxing city under Grant 2018C10015, and in part by the Natural Science Foundation of Shanghai under Grants 18ZR1440600 and 19ZR1461100. The associate editor coordinating the review of this manuscript and approving it for publication was Prof. Marco Grangetto. (Qingyang Zhou, Liping Zhao and Kailun Zhou contributed equally to this work.)

语种：英文

外文关键词：Audio video coding standard; screen content coding; string prediction; 4:2:0 format

外文摘要：In the past, string prediction (also known as string matching) was applied only to RGB and YUV 4:4:4 format screen content coding. This paper proposes a string prediction approach to 4:2:0 format screen content coding implemented in the third generation of Audio Video Standard (AVS3) in China. String prediction is applied to both YUV CU and Y CU. To further improve the coding performance, several improved technicals of string prediction are presented, including a mixed string searching strategy for finding the optimal reference string, a joint picture-level, CU-level, and pixel-level early termination strategy to reduce coding complexity, and two effective coding methods for string prediction parameters. For low-complexity hardware implementation of string prediction decoder, the memory access bandwidth is reduced by introducing string constraints. Meanwhile, string prediction reuses the reference pixel buffer of intra block copy (IBC). Compared with the newest AVS3 reference software HPM7.0 with string prediction disabled, the proposed string prediction approach achieves up to 18.48% Y BD-rate reduction. Using AVS3 Screen Content Coding (SCC) Common Test Condition and YUV test sequences in Text and Graphics with Motion category, the proposed technique achieves an average Y BD-rate reduction of 10.33%, 8.47%, 6.91% for All Intra (AI), Random Access (RA) and Low Delay (LD) configurations, respectively, with low additional encoding and decoding complexity. The proposed string prediction approach has been adopted in the newest AVS3 reference software HPM7.0.