Overview of the Versatile Video Coding (VVC) Standard and its Applications

Abstract

Versatile Video Coding (VVC) was finalized in July 2020 as the most recent international video coding standard. It was developed by the Joint Video Experts Team (JVET) of the ITU-T Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG) to serve an ever-growing need for improved video compression as well as to support a wider variety of today's media content and emerging applications. This paper provides an overview of the novel technical features for new applications and the core compression technologies for achieving significant bit rate reductions in the neighborhood of 50% over its predecessor for equal video quality, the High Efficiency Video Coding (HEVC) standard, and 75% over the currently most-used format, the Advanced Video Coding (AVC) standard. It is explained how these new features in VVC provide greater versatility for applications. Highlighted applications include video with resolutions beyond standard-and high-definition, video with high dynamic range and wide color gamut, adaptive streaming with resolution changes, computer-generated and screen-captured video, ultralow-delay streaming, 360° immersive video, and multilayer coding e.g., for scalability. Furthermore, early implementations are presented to show that the new VVC standard is implementable and ready for real-world deployment.

Inverse Transform Using Linearity for Video Coding

“…In most video coding standards, to reduce computational complexity, the 2D transform and inverse transform are implemented as separable transforms by applying the 1D inverse transform in Equation (2) to each row and each column. The separable inverse transform for non-square block size is expressed in Equation (6).…”

“…Transform coding is an important part of video coding, and it has been successfully adopted in most video coding standards, including MPEG-4 AVC (advanced video coding)/H.264 [1,2], HEVC (high efficiency video coding)/H.265 [3,4], and VVC/H.266 [5,6]. In hybrid block-based video coding, a transform is applied to the residual signal obtained after intra/inter-prediction, and the residual signals in the spatial domain are converted into the frequency domain.…”

AV1 and VVC Video Codecs: Overview on Complexity Reduction and Hardware Design

“…VVC enhances many of the inter prediction tools from HEVC, including the conventional ME and merge mode. The main VVC novelties are: (i) the use of Affine Motion Compensation (AMC) [24], to represent higher-order motion beyond translation, such as rotation, scaling, and shearing; (ii) the increase in the motion vector (MV) precision to 1/16 (compared to 1/4 in HEVC); (iii) Adaptive Motion Vector Resolution (AMVR), that allows the selection of the MV precision according to the coded mode [25]; (iv) Geometric Partitioning Mode (GPM) [26], which splits a CU into two non-rectangular partitions to perform the inter prediction separately; (v) Combined Inter and Intra Prediction (CIIP), which combines the inter prediction (merge mode) with the intra prediction (planar mode) [27]; (vi) Decoder-side MV refinement (DMVR), intending to improve the compression efficiency [28]; (vii) Bidirectional Optical Flow (BDOF), which explores the optical flow concept [29]; (viii) Prediction Refinement with Optical Flow (PROF), used for affine prediction also exploring the optical flow concept [4]; (ix) Bi-prediction with CU-level Weights (BCW), which uses till five predefined weights instead of the traditional weighted prediction [4]; (x) Extended Merge Prediction, allowing a new set of tools to improve the merge process [4].…”

“…The quantization brings a small number of improvements in both encoders. In VVC, specifically, the Quantization Parameter (QP) was increased from 53 to 61, to allow higher compression rates, and the Dependent Quantization (DQ) tool was included allowing the use of two scalar quantizers [4].…”

“…The AOMedia Video 1 (AV1) [2], [3] and the Versatile Video Coding (VVC) [4], [5] are the next-generation video coding formats developed to tackle these problems. AV1 was released in June 2018 by the Alliance for Open Media (AOMedia) industry consortium, as the successor of VP9 [6].…”