低延迟视频编码技术  

Low-latency video coding techniques

作　　者：宋利[1,2] 刘孝勇 武国庆 朱辰 黄琰 解蓉[1] 张文军[1,2] SONG Li;LIU Xiaoyong;WU Guoqing;ZHU Chen;HUANG Yan;XIE Rong;ZHANG Wenjun(Institute of Image Communication and Network Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Cooperative Medianet Innovation Center,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学图像通信与网络工程研究所,上海200240 [2]上海交通大学未来媒体网络协同创新中心,上海200240

出　　处：《北京航空航天大学学报》2021年第3期558-571,共14页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家重点研发计划(2019YFB1802701);国家自然科学基金(61671296)。

摘　　要：随着视频编码和视频传输技术的广泛应用,视频需求量剧增,实时视频通信成为视频行业的一项重要研究内容,核心目标是提供更好的用户体验和更低的延迟。低延迟视频编码是实时视频通信应用的关键部分,通过降低编码延迟可以有效地降低系统的整体延迟。首先,分析了视频传输系统的延迟来源,从通用的视频编码框架出发着重介绍了编码延迟的产生机制;其次,概述了国内外主流的视频编码标准,介绍了率失真优化技术的原理和模型,为低延迟视频编码器的设计提供了理论基础;最后,从参考结构、流水线设计、编码模式搜索、码率控制和硬件加速多个维度描述了优化编码延迟的技术手段,并总结了业界具有代表性的低延迟视频编码方案,简要说明了现有低延迟视频编码技术的局限性,并对未来的发展方向做了展望。With the widespread usage of video coding and transmission techniques,demands for video have increased dramatically.Real-time video communication has become the research focus of the video industry.Its core goal is to provide a better user experience and lower latency.Low-latency video coding is a key component for real-time video communication applications.The overall system latency can be effectively reduced by reducing the coding latency.First,this paper analyzes sources of latency in the video transmission system.Focusing on the general video coding framework,this paper introduces the generation mechanism of the coding latency.Then,mainstream video coding standards at home and abroad are outlined.The detailed description of the principle and models of rate-distortion optimization techniques provides a theoretical basis for the design of low-latency video encoders.Additionally,this paper summarizes how to optimize the coding latency in terms of the reference structures,pipeline design,encoding modes search,rate control,and hardware acceleration and generalizes industrial representative low-latency video coding schemes.Finally,this paper summarizes the limitations of the existing low-latency video coding techniques and presents future research directions.

关 键 词：低延迟 视频编码 实时视频通信 率失真优化 编码用例 

分 类 号：TN919.8[电子电信—通信与信息系统]