Scalability is an essential coding feature for adaptive video streaming applications, notably considering the growing heterogeneity of the transmission, display and consumption environments. Versatile video coding (VVC) is the emerging video coding standard, targeting offering higher compression efficiency regarding previous standards to further facilitate already available and novel video applications, notably at higher spatial resolutions. In this context, this letter proposes the first VVC-based quality scalability extension, targeting to offer higher compression efficiency than the native VVC quality scalability solution. The proposed Quality Scalable Versatile Video Coding (QS-VVC) solution is designed based on a layered coding approach with one base layer (BL) and one or more enhancement layers (EL). To achieve higher compression performance, a novel joint layer referencing approach is proposed where the base and enhancement layers decoded information are jointly exploited to create a new EL coding reference. Experimental results shown that the proposed QS-VVC codec outperforms the most relevant benchmarks, notably VVC-based simulcasting, native VVC quality scalability, and the previous Scalable High Efficiency Video Coding (SHVC) standard.

中文翻译：

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基于质量可扩展性和联合层参考的多功能视频编码


可扩展性是自适应视频流应用的一项重要编码功能，特别是考虑到传输、显示和消费环境日益增长的异构性。多功能视频编码 (VVC) 是新兴的视频编码标准，其目标是相对于先前的标准提供更高的压缩效率，以进一步促进现有的新颖视频应用，特别是在更高的空间分辨率下。在此背景下，这封信提出了第一个基于 VVC 的质量可扩展性扩展，旨在提供比原生 VVC 质量可扩展性解决方案更高的压缩效率。所提出的质量可扩展通用视频编码（QS-VVC）解决方案是基于具有一个基础层（BL）和一个或多个增强层（EL）的分层编码方法而设计的。为了实现更高的压缩性能，提出了一种新颖的联合层参考方法，其中联合利用基础层和增强层解码信息来创建新的 EL 编码参考。实验结果表明，所提出的 QS-VVC 编解码器的性能优于最相关的基准，特别是基于 VVC 的联播、本机 VVC 质量可扩展性以及之前的可扩展高效视频编码 (SHVC) 标准。