ISO/IEC 23090-3:2026

• Abstract:

  This document specifies a video coding technology known as versatile video coding (VVC), comprising a video coding technology with a compression capability that is substantially beyond that of the prior generations of such standards and with sufficient versatility for effective use in a broad range of applications. Only the syntax format, semantics, and associated decoding process requirements are specified, while other matters such as pre-processing, the encoding process, system signalling and multiplexing, data loss recovery, post-processing, and video display are considered to be outside the scope of this document. Additionally, the internal processing steps performed within a decoder are also considered to be outside the scope of this document; only the externally observable output behaviour is required to conform to the specifications of this document. This document is designed to be generic in the sense that it serves a wide range of applications, bit rates, resolutions, qualities and services. Applications include, but are not limited to, video coding for digital storage media, television broadcasting and real-time communication. In the course of creating This document, various requirements from typical applications have been considered, necessary algorithmic elements have been developed, and these have been integrated into a single syntax. Hence, this document is designed to facilitate video data interchange among different applications.

• Status: Published
• Publication Date: 27-Sep-2026
• ICS: 35.040.40 - Coding of audio, video, multimedia and hypermedia information
• Technical Committee: ISO/IEC JTC 1/SC 29 - Coding of audio, picture, multimedia and hypermedia information
• Drafting Committee: ISO/IEC JTC 1/SC 29/WG 5 - MPEG Joint Video Coding Team(s) with ITU-T SG 16
• Current Stage: 6060 - International Standard published
• Start Date: 28-Sep-2026
• Due Date: 16-Jul-2027
• Completion Date: 28-Sep-2026

• Revises: ISO/IEC 23090-3:2024 - Information technology — Coded representation of immersive media — Part 3: Versatile video coding
• Effective Date: 24-Jan-2026

Overview

ISO/IEC 23090-3:2026 is the International Standard for versatile video coding (VVC) within the ISO/IEC series Information technology - Coded representation of immersive media. It specifies the syntax format, semantics, and associated decoding process requirements for a modern video coding technology designed to deliver substantially improved compression compared with prior generations of video coding standards.

This standard is intended to support a broad range of applications, bit rates, resolutions, qualities, and services. It is especially relevant where efficient video compression, interoperability, and reliable decoder conformance are important. The document is structured to support practical deployment across sectors such as digital storage media, television broadcasting, video streaming services, and real-time communication.

A key strength of ISO/IEC 23090-3:2026 is its generic design. It integrates algorithmic elements from typical use cases into a single syntax, helping facilitate video data interchange among different applications. The standard focuses on what must be represented and decoded, while leaving encoding methods and many system-level functions outside its scope.

Key Topics

ISO/IEC 23090-3:2026 covers the core technical framework needed for VVC bitstream conformance and decoder behavior.

• Syntax and semantics

  • Defines how coded video data is represented
  • Specifies the meaning of syntax elements and the order in which they are parsed

• Decoding process requirements

  • Describes the externally observable output behavior required for conformance
  • Provides the basis for consistent decoded output across conforming implementations

• Profiles, tiers, and levels

  • Establishes subsets of the full syntax for practical implementation
  • Supports different capability ranges for diverse decoder and application requirements

• Bitstream and picture formats

  • Addresses bitstream structure, picture partitioning, and scanning processes
  • Supports structured handling of coded video data

• Supplemental enhancement information

  • Includes conformance-related SEI usage and integration with related VUI and SEI specifications

Applications

ISO/IEC 23090-3:2026 is relevant wherever high-efficiency video compression and interoperability matter. Typical application areas include:

• Video coding for digital storage media
• Television broadcasting
• Video streaming services
• Real-time communication
• Immersive media, including 360° and other advanced viewing formats

It is particularly valuable for organizations working with ultra-high-definition video, high dynamic range (HDR), and wide color gamut content. The standard is also well suited to environments where consistent decoding behavior and standardized interchange of encoded video are important across devices and services.

Related Standards

ISO/IEC 23090-3:2026 works in conjunction with several related standards:

• ISO/IEC 23090-13 - Video decoding interface for immersive media
• ISO/IEC 23001-11 - Energy-efficient media consumption (green metadata)
• Rec. ITU-T H.274 | ISO/IEC 23002-7 - Versatile supplemental enhancement information messages for coded video bitstreams
• Rec. ITU-T T.35 - Procedure for the allocation of ITU-T defined codes for non standard facilities

Together, these standards support a broader ecosystem for immersive media coding, decoder interoperability, and video system integration. For stakeholders evaluating VVC standards, ISO/IEC 23090-3:2026 remains a key reference for modern video compression standardization and cross-platform video delivery.

International
Standard
ISO/IEC 23090-3
Fourth edition
Information technology — Coded
2026-09
representation of immersive
media —
Part 3:
Versatile video coding
Technologies de l'information — Représentation codée de média
immersifs —
Partie 3: Codage vidéo polyvalent
Reference number
© ISO/IEC 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
© ISO/IEC 2026 – All rights reserved
ii
Contents
Foreword viii
Introduction x
1 Scope 1
2 Normative references 1
3 Terms and definitions 1
4 Abbreviated terms 17
5 Conventions 19
5.1 General 20
5.2 Arithmetic operators 20
5.3 Logical operators 20
5.4 Relational operators 21
5.5 Bit-wise operators 21
5.6 Assignment operators 21
5.7 Range notation 22
5.8 Mathematical functions 22
5.9 Order of operation precedence 22
5.10 Variables, syntax elements and tables 23
5.11 Text description of logical operations 24
5.12 Processes 25
6 Bitstream and picture formats, partitionings, scanning processes and neighbouring
relationships 26
6.1 Bitstream formats 26
6.2 Source, decoded and output picture formats 26
6.3 Partitioning of pictures, subpictures, slices, tiles, and CTUs 28
6.3.1 Partitioning of pictures into subpictures, slices, and tiles 28
6.3.2 Block, quadtree and multi-type tree structures 31
6.3.3 Spatial or component-wise partitionings 32
6.4 Availability processes 32
6.4.1 Allowed quad split process 32
6.4.2 Allowed binary split process 33
6.4.3 Allowed ternary split process 35
6.4.4 Derivation process for neighbouring block availability 36
6.5 Scanning processes 37
6.5.1 CTB raster scanning, tile scanning, and subpicture scanning processes 37
6.5.2 Up-right diagonal scan order array initialization process 42
6.5.3 Horizontal and vertical traverse scan order array initialization process 42
7 Syntax and semantics 43
7.1 Method of specifying syntax in tabular form 43
7.2 Speci�ication of syntax functions and descriptors 44
7.3 Syntax in tabular form 46
7.3.1 NAL unit syntax 46
7.3.2 Raw byte sequence payloads, trailing bits and byte alignment syntax 47
7.3.3 Profile, tier, and level syntax 67
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7.3.4 DPB parameters syntax 70
7.3.5 Timing and HRD parameters syntax 70
7.3.6 Supplemental enhancement information message syntax 72
7.3.7 Slice header syntax 72
7.3.8 Weighted prediction parameters syntax 75
7.3.9 Reference picture lists syntax 76
7.3.10 Reference picture list structure syntax 76
7.3.11 Slice data syntax 77
7.4 Semantics 101
7.4.1 General 101
7.4.2 NAL unit semantics 101
7.4.3 Raw byte sequence payloads, trailing bits and byte alignment semantics 110
7.4.4 Pro�ile, tier, and level semantics 171
7.4.5 DPB parameters semantics 177
7.4.6 Timing and HRD parameters semantics 178
7.4.7 Supplemental enhancement information message semantics 183
7.4.8 Slice header semantics 183
7.4.9 Weighted prediction parameters semantics 194
7.4.10 Reference picture lists semantics 195
7.4.11 Reference picture list structure semantics 197
7.4.12 Slice data semantics 198
8 Decoding process 226
8.1 General decoding process 226
8.2 NAL unit decoding process 229
8.3 Slice decoding process 229
8.3.1 Decoding process for picture order count 229
8.3.2 Decoding process for reference picture lists construction 231
8.3.3 Decoding process for reference picture marking 237
8.3.4 Decoding process for generating unavailable reference pictures 238
8.3.5 Decoding process for symmetric motion vector difference reference indices 238
8.3.6 Decoding process for collocated picture and no backward prediction 239
8.4 Decoding process for coding units coded in intra prediction mode 240
8.4.1 General decoding process for coding units coded in intra prediction mode 240
8.4.2 Derivation process for luma intra prediction mode 242
8.4.3 Derivation process for chroma intra prediction mode 245
8.4.4 Cross-component chroma intra prediction mode checking process 247
8.4.5 Decoding process for intra blocks 248
8.5 Decoding process for coding units coded in inter prediction mode 285
8.5.1 General decoding process for coding units coded in inter prediction mode 285
8.5.2 Derivation process for motion vector components and reference indices 290
8.5.3 Decoder-side motion vector re�inement process 314
8.5.4 Derivation process for geometric partitioning mode motion vector
components and reference indices 320
8.5.5 Derivation process for subblock motion vector components and
reference indices 322
8.5.6 Decoding process for inter blocks 352
8.5.7 Decoding process for geometric partitioning mode inter blocks 379
8.5.8 Decoding process for the residual signal of coding blocks coded in inter
prediction mode 385
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iv
8.5.9 Decoding process for the reconstructed signal of chroma coding blocks
coded in inter prediction mode 387
8.6 Decoding process for coding units coded in IBC prediction mode 389
8.6.1 General decoding process for coding units coded in IBC prediction mode 389
8.6.2 Derivation process for block vector components for IBC blocks 391
8.6.3 Decoding process for IBC blocks 396
8.7 Scaling, transformation and array construction process 397
8.7.1 Derivation process for quantization parameters 397
8.7.2 Scaling and transformation process 399
8.7.3 Scaling process for transform coef�icients 400
8.7.4 Transformation process for scaled transform coef�icients 403
8.7.5 Picture reconstruction process 424
8.8 In-loop filter process 428
8.8.1 General 428
8.8.2 Picture inverse mapping process for luma samples 429
8.8.3 Deblocking �ilter process 430
8.8.4 Sample adaptive offset process 462
8.8.5 Adaptive loop �ilter process 465
9 Parsing process 478
9.1 General 478
9.2 Parsing process for k-th order Exp-Golomb codes 479
9.2.1 General 479
9.2.2 Mapping process for signed Exp-Golomb codes 480
9.3 CABAC parsing process for slice data 480
9.3.1 General 480
9.3.2 Initialization process 482
9.3.3 Binarization process 507
9.3.4 Decoding process �low 518
Annex A   (normative) Profiles, tiers and levels 537
A.1 Overview of profiles, tiers and levels 537
A.2 Requirements on video decoder capability 537
A.3 Pro�iles 538
A.3.1 Main 10 and Main 10 Still Picture profiles 538
A.3.2 Main 10 4:4:4 and Main 10 4:4:4 Still Picture pro�iles 539
A.3.3 Multilayer Main 10 pro�ile 540
A.3.4 Multilayer Main 10 4:4:4 pro�ile 540
A.3.5 Operation range extensions pro�iles 540
A.4 Tiers and levels 544
A.4.1 General tier and level limits 544
A.4.2 Pro�ile-speci�ic level limits 546
A.4.3 Effect of level limits on picture rate 550
Annex B   (normative) Byte stream format 558
B.1 General 558
Annex C   (normative) Hypothetical reference decoder 561
C.1 General 561
C.2 Operation of the CPB 567
C.2.1 General 567
C.2.2 Timing of DU arrival 567
© ISO/IEC 2026 – All rights reserved
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C.2.3 Timing of DU removal and decoding of DU 570
C.3 Operation of the DPB 573
C.3.1 General 573
C.3.2 Removal of pictures from the DPB before decoding of the current picture 573
C.3.3 Picture output 574
C.3.4 Current decoded picture marking and storage 575
C.4 Bitstream conformance 575
C.5 Decoder conformance 577
C.5.1 General 577
C.5.2 Operation of the output order DPB 578
C.5.2.1 General 578
C.5.2.2 Output and removal of pictures from the DPB 579
C.5.2.3 Additional bumping 580
C.5.2.4 "Bumping" process 580
C.6 General sub-bitstream extraction process 580
C.7 Subpicture sub-bitstream extraction process 582
Annex D   (normative) Supplemental enhancement information and use of SEI and VUI 588
D.1 General 588
D.2 General SEI payload 588
D.2.1 General SEI payload syntax 588
D.2.2 General SEI payload semantics 591
D.3 Buffering period SEI message 595
D.3.1 Buffering period SEI message syntax 595
D.3.2 Buffering period SEI message semantics 596
D.4 Picture timing SEI message 601
D.4.1 Picture timing SEI message syntax 601
D.4.2 Picture timing SEI message semantics 602
D.5 DU information SEI message 607
D.5.1 DU information SEI message syntax 607
D.5.2 DU information SEI message semantics 608
D.6 Scalable nesting SEI message 609
D.6.1 Scalable nesting SEI message syntax 609
D.6.2 Scalable nesting SEI message semantics 610
D.7 Subpicture level information SEI message 612
D.7.1 Subpicture level information SEI message syntax 612
D.7.2 Subpicture level information SEI message semantics 613
D.8 SEI manifest SEI message 616
D.8.1 SEI manifest SEI message syntax 616
D.8.2 SEI manifest SEI message semantics 617
D.9 SEI prefix indication SEI message 618
D.9.1 SEI prefix indication SEI message syntax 618
D.9.2 SEI pre�ix indication SEI message semantics 619
D.10 Constrained RASL encoding indication SEI message 620
D.10.1 Constrained RASL encoding indication SEI message syntax 620
D.10.2 Constrained RASL encoding indication SEI message semantics 620
D.11 Use of ITU-T H.274 | ISO/IEC 23002-7 VUI parameters 621
D.12 Use of SEI messages specified in other documents 621
D.12.1 General 621
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D.12.2 Use of the �ilm grain characteristics SEI message 622
D.12.3 Use of the decoded picture hash SEI message 622
D.12.4 Use of the dependent random access point (DRAP) indication SEI message 623
D.12.5 Use of the equirectangular projection, generalized cubemap projection,
and region-wise packing SEI messages 623
D.12.6 Use of the frame-�ield information SEI message 623
D.12.7 Use of the annotated regions SEI message 624
D.12.8 Use of the extended dependent random access point (EDRAP) indication
SEI message 624
D.12.9 Use of the colour transform information SEI message 624
D.12.10 Use of the shutter interval information SEI message 624
D.12.11 Use of the neural network post-�ilter characteristics SEI message and
the neural network post-�ilter activation SEI message 624
D.12.12 Use of the phase indication SEI message 628
D.12.13 Use of the SEI processing order and processing order nesting SEI messages 628
D.12.14 Use of the encoder optimization information SEI messages 629
D.12.15 Use of the source picture timing SEI message 629
D.12.16 Use of the object mask information SEI message 629
D.12.17 Use of the digitally signed content initialization, digitally signed content
selection, and digitally signed content veri�ication SEI messages 630
D.12.18 Use of the generative face video SEI message 630
D.12.19 Use of the generative enhancement face video SEI message 630
D.12.20 Use of the packed regions information SEI message 631
Bibliography 632
© ISO/IEC 2026 – All rights reserved
vii
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members
of ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
document should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC
Directives, Part 2 (see www.iso.org/directives or www.iec.ch/members_experts/refdocs).
ISO and IEC draw attention to the possibility that the implementation of this document may involve the use of
(a) patent(s). ISO and IEC take no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO and IEC had received notice
of (a) patent(s) which may be required to implement this document. However, implementers are cautioned
that this may not represent the latest information, which may be obtained from the patent database available
at www.iso.org/patents and https://patents.iec.ch. ISO and IEC shall not be held responsible for identifying
any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www.iso.org/iso/foreword.html.
In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information, in collaboration with
ITU-T (as ITU-T H.266).
This fourth edition cancels and replaces the third edition (ISO/IEC 23090-3:2024), which has been technically
revised. It also replaces ISO/IEC 23090-3:2024/Amd1.
The main changes are as follows:
— the addition of support for 15 SEI messages specified in Rec. ITU-T H.274 | ISO/IEC 23002-7, namely 1)
SEI processing order, 2) processing order nesting, 3) encoder optimization information, 4) source picture
timing information, 5) object mask information, 6) modality information, 7) text description information,
8) digitally signed content initialization, 9) digitally signed content selection, 10) digitally signed content
verification, 11) generative face video, 12) generative enhancement face video, 13) AI usage restrictions
request, 14) packed regions information, and 15) image format metadata.
— some updates to the interface text for support of the two neural-network post-filter (NNPF) SEI messages.
A list of all parts in the ISO/IEC 23090 series can be found on the ISO and IEC websites.
© ISO/IEC 2026 – All rights reserved
viii
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html and www.iec.ch/national-
committees.
© ISO/IEC 2026 – All rights reserved
ix
Introduction
Purpose
This document specifies a video coding technology known as versatile video coding. It has been designed with
two primary goals. The first of these is to specify a video coding technology with a compression capability that
is substantially beyond that of the prior generations of such standards, and the second is for this technology
to be highly versatile for effective use in a broader range of applications than that addressed by prior
standards. Some key application areas for the use of this document particularly include ultra-high-definition
video (e.g., with 3840×2160 or 7620×4320 picture resolution and bit depth of 10 bits as specified in Rec. ITU-
R BT.2100), video with a high dynamic range and wide colour gamut (e.g., with the perceptual quantization or
hybrid log-gamma transfer characteristics specified in Rec. ITU-R BT.2100), and video for immersive media
applications such as 360° omnidirectional video projected using a common projection format such as the
equirectangular or cubemap projection formats, in addition to the applications that have commonly been
addressed by prior video coding standards.
Profiles, tiers, and levels
This document is designed to be versatile in the sense that it serves a wide range of applications, bit rates,
resolutions, qualities, and services. Applications include, but are not limited to, video coding for digital storage
media, television broadcasting, video streaming services, real-time communication. In the course of creating
this document, various requirements from typical applications have been considered, necessary algorithmic
elements have been developed, and these have been integrated into a single syntax. Hence, this document is
designed to facilitate video data interchange among different applications.
Considering the practicality of implementing the full syntax of this document, however, a limited number of
subsets of the syntax are also stipulated by means of "profiles", "tiers", and "levels". These and other related
terms are formally defined in Clause 3.
A "profile" is a subset of the entire bitstream syntax that is specified in this document. Within the bounds
imposed by the syntax of a given profile it is still possible to require a very large variation in the performance
of encoders and decoders depending upon the values taken by syntax elements in the bitstream, such as the
specified size of the decoded pictures. In many applications, it is currently neither practical nor economical to
implement a decoder capable of dealing with all hypothetical uses of the syntax within a particular profile.
In order to deal with this problem, "tiers" and "levels" are specified within each profile. A level of a tier is a
specified set of constraints imposed on values of the syntax elements in the bitstream. Some of these
constraints are expressed as simple limits on values, while others take the form of constraints on arithmetic
combinations of values (e.g. picture width multiplied by picture height multiplied by number of pictures
decoded per second). A level specified for a lower tier is more constrained than a level specified for a higher
tier.
Coded video content conforming to this document uses a common syntax. In order to achieve a subset of the
complete syntax, flags, parameters, and other syntax elements are included in the bitstream that signal the
presence or absence of syntactic elements that occur later in the bitstream.
Encoding process, decoding process, and use of VUI parameters and SEI messages
Any encoding process that produces bitstream data that conforms to the specified bitstream syntax format
requirements of this document is considered to be in conformance with the requirements of this document.
The decoding process is specified such that all decoders that conform to a specified combination of capabilities
known as the profile, tier, and level will produce numerically identical cropped decoded output pictures when
invoking the decoding process associated with that profile for a bitstream conforming to that profile, tier and
level. Any decoding process that produces identical cropped decoded output pictures to those produced by
© ISO/IEC 2026 – All rights reserved
x
the process described herein (with the correct output order or output timing, as specified) is considered to be
in conformance with the requirements of this document.
Rec. ITU-T H.274 | ISO/IEC 23002-7 specifies the syntax and semantics of the video usability information (VUI)
parameters and supplemental enhancement information (SEI) messages that do not affect the conformance
specifications in Annex C. These VUI parameters and SEI messages may be used together with this document.
Versions of this document
Rec. ITU-T H.266 | ISO/IEC 23090-3 version 1 refers to the first approved version of this document. The first
edition published by ISO/IEC as ISO/IEC 23090-3:2021 corresponded to the first version.
Rec. ITU-T H.266 | ISO/IEC 23090-3 version 2 refers to the integrated text additionally containing operation
range extensions, a new level (level 6.3), additional supplement enhancement information, and corrections to
various minor defects in the prior content of the document. The second edition published by ISO/IEC as
ISO/IEC 23090-3:2022 corresponded to the second version.
Rec. ITU-T H.266 | ISO/IEC 23090-3 version 3 refers to the integrated text containing the specification of a
new level (level 15.5) for the video profiles to provide a suitable label for bitstreams that can exceed the limits
of all other specified levels, additional supplement enhancement information, and corrections to various
minor defects in the prior content of the document. This document corresponds to the third version. At the
time of publication of this document, a corresponding third edition of Rec. ITU-T H.266 was in preparation for
publication by ITU-T.
Rec. ITU-T H.266 | ISO/IEC 23090-3 version 4 (the current version) refers to the integrated text containing
the specification of 15 additional SEI messages through referencing the Versatile Supplemental Enhancement
Information (VSEI) standard (Rec. ITU T H.274 | ISO/IEC 23002 7), namely 1) SEI processing order, 2)
processing order nesting, 3) encoder optimization information, 4) source picture timing information, 5) object
mask information, 6) modality information, 7) text description information, 8) digitally signed content
initialization, 9) digitally signed content selection, 10) digitally signed content verification, 11) generative face
video, 12) generative enhancement face video, 13) AI usage restrictions request, 14) packed regions
information, and 15) image format metadata. The additions also includes some updates to the interface text
for support of the two neural-network post-filter (NNPF) SEI messages and corrections to various minor
defects in the prior content of the document. This document corresponds to the fourth version. At the time of
publication of this document, a corresponding fourth edition of Rec. ITU-T H.266 was in preparation for
publication by ITU-T.
Overview of the design characteristics
The coded representation specified in the syntax is designed to enable a high compression capability for a
desired image or video quality. The algorithm is typically not mathematically lossless, as the exact source
sample values are typically not preserved through the encoding and decoding processes, although some
modes are included that provide lossless coding capability. A number of techniques are specified to enable
highly efficient compression. Encoding algorithms (not specified within the scope of this document) may select
between inter, intra, intra block copy (IBC), and palette coding for block-shaped regions of each picture. Inter
coding uses motion vectors for block-based inter-picture prediction to exploit temporal statistical
dependencies between different pictures, intra coding uses various spatial prediction modes to exploit spatial
statistical dependencies in the source signal within the same picture, and intra block copy coding uses block
displacement vectors to reference previously decoded regions of the same picture to exploit statistical
similarities among different areas of the same picture. Motion vectors, intra prediction modes, and IBC block
vectors are specified for a variety of block sizes in the picture. The prediction residual can then be further
compressed using a spatial transform to remove spatial correlation inside a block before it is quantized,
producing a possibly irreversible process that typically discards less important visual information while
forming a close approximation to the source samples. Finally, the motion vectors, intra prediction modes, and
© ISO/IEC 2026 – All rights reserved
xi
block vectors can also be further compressed using a variety of prediction mechanisms, and, after prediction,
are combined with the quantized transform coefficient information and encoded using arithmetic coding.
How to read this document
It is suggested that the reader starts with Clause 1 and moves on to Clause 3. Clause 6 should be read for the
geometrical relationship of the source, input, and output of the decoder. Clause 7 specifies the order to parse
syntax elements from the bitstream. See subclauses 7.1 to 7.3 for syntactical order and subclause 7.4 for
semantics; e.g. the scope, restrictions, and conditions that are imposed on the syntax elements. The actual
parsing for most syntax elements is specified in Clause 9. Finally, Clause 8 specifies how the syntax elements
are mapped into decoded samples. Annexes A through D also form an integral part of this document.
Annex A specifies profiles, each being tailored to certain application domains, and defines the so-called tiers
and levels of the profiles. Annex B specifies syntax and semantics of a byte stream format for delivery of coded
video as an ordered stream of bytes. Annex C specifies the hypothetical reference decoder, bitstream
conformance, decoder conformance, and the use of the hypothetical reference decoder to check bitstream and
decoder conformance. Annex D specifies syntax and semantics for supplemental enhancement information
(SEI) message payloads that affect the conformance specifications in Annex C. Rec. ITU-T H.274 | ISO/IEC
23002-7 specifies the syntax and semantics of the video usability information (VUI) parameters as well as SEI
messages that do not affect the conformance specifications in Annex C. These VUI parameters and SEI
messages may be used together with this document.
The term "this document" is used to refer to this Recommendation | International Standard.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “may” indicates a permission;
— “can” indicates a possibility or a capability.
Information marked as “NOTE” is intended to assist the understanding or use of the document. “Notes to entry”
used in Clause 3 provide additional information that supplements the terminological data and can contain
provisions relating to the use of a term.

© ISO/IEC 2026 – All rights reserved
xii
International Standard ISO/IEC 23090-3:2026(en)

Information technology — Coded representation of
immersive media —
Part 3:
Versatile video coding
1 Scope
This document specifies a video coding technology known as versatile video coding (VVC), comprising a video
coding technology with a compression capability that is substantially beyond that of the prior generations of
such standards and with sufficient versatility for effective use in a broad range of applications.
Only the syntax format, semantics, and associated decoding process requirements are specified, while other
matters such as pre-processing, the encoding process, system signalling and multiplexing, data loss recovery,
post-processing, and video display are considered to be outside the scope of this document. Additionally, the
internal processing steps performed within a decoder are also considered to be outside the scope of this
document; only the externally observable output behaviour is required to conform to the specifications of this
document.
This document is designed to be generic in the sense that it serves a wide range of applications, bit rates,
resolutions, qualities and services. Applications include, but are not limited to, video coding for digital storage
media, television broadcasting and real-time communication. In the course of creating This document, various
requirements from typical applications have been considered, necessary algorithmic elements have been
developed, and these have been integrated into a single syntax. Hence, this document is designed to facilitate
video data interchange among different applications.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 23001-11, Information Technology — MPEG Systems technologies — Part 11: Energy-efficient media
consumption (green metadata)
Rec. ITU-T H.274 | ISO/IEC 23002-7, Versatile supplemental enhancement information messages for coded video
bitstreams
ISO/IEC 23090-13, Information technology — Coded representation of immersive media — Part 13: Video
decoding interface for immersive media
Rec. ITU-T T.35, Procedure for the allocation of ITU-T defined codes for non standard facilities
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
 ISO Online browsing platform: available at https://www.iso.org/obp
 IEC Electropedia: available at https://www.electropedia.org/
© ISO/IEC 2026 – All rights reserved
3.1
access unit
set of PUs that belong to different layers and contain coded pictures associated with the same time for output
from the DPB
3.2
adaptation parameter set
syntax structure containing syntax elements that apply to zero or more slices as determined by zero or more
syntax elements found in slice headers
3.3
adaptive colour transform
cross-component transform applied to the decoded residual of a coding unit in the 4:4:4 colour format prior
to reconstruction and loop filtering
3.4
adaptive loop filter
filtering process that is applied as part of the decoding process and is controlled by parameters conveyed in
an APS
3.5
ALF APS
APS that controls the ALF process
3.6
associated GDR picture
previous GDR picture (when present) in decoding order, for a particular picture with nuh_layer_id equal to a
particular value layerId, that has nuh_layer_id equal to layerId and between which and the particular picture
in decoding order there is no IRAP picture with nuh_layer_id equal to layerId
3.7
associated IRAP picture
previous IRAP picture (when present) in decoding order, for a particular picture with nuh_layer_id equal to a
particular value layerId, that has nuh_layer_id equal to layerId and between which and the particular picture
in decoding order there is no GDR picture with nuh_layer_id equal to layerId
3.8
associated IRAP subpicture
previous IRAP subpicture (when present) in decoding order, for a particular subpicture with nuh_layer_id
equal to a particular value layerId and subpicture index equal to a particular value subpicIdx, that has
nuh_layer_id equal to layerId and subpicture index equal to subpicIdx and between which and the particular
subpicture in decoding order there is no GDR subpicture with nuh_layer_id equal to layerId and subpicture
index equal to subpicIdx
3.9
associated non-VCL NAL unit
non-VCL NAL unit (when present) for a VCL NAL unit where the VCL NAL unit is the associated VCL NAL unit
of the non-VCL NAL unit
3.10
associated VCL NAL unit
preceding VCL NAL unit in decoding order for a non-VCL NAL unit with nal_unit_type equal to EOS_NUT,
EOB_NUT, SUFFIX_APS_NUT, SUFFIX_SEI_NUT, FD_NUT, RSV_NVCL_27, UNSPEC_30, or UNSPEC_31; or
otherwise the next VCL NAL unit in decoding order
© ISO/IEC 2026 – All rights reserved
3.11
bin
bit of a bin string
3.12
bin string
intermediate binary representation of values of syntax elements from the binarization of the syntax element
3.13
binarization
set of bin strings for all possible values of a syntax element
3.14
binarization process
unique mapping process of all possible values of a syntax element onto a set of bin strings
3.15
binary split
split of a rectangular MxN block of samples into two blocks where a vertical split results in a first (M / 2)xN
block and a second (M / 2)xN block, and a horizontal split results in a first Mx(N / 2) block and a second
Mx(N / 2) block
3.16
bi-predictive slice
B slice
slice that is decoded using intra prediction or using inter prediction with at most two motion vectors and
reference indices to predict the sample values of each block
3.17
bitstream
sequence of bits, in the form of a NAL unit stream or a byte stream, that forms the representation of a
sequence of AUs forming one or more coded video sequences (CVSs)
3.18
block
MxN (M-column by N-row) array of samples, or an MxN array of transform coefficients
3.19
block vector
two-dimensional vector that provides an offset from the coordinates of the current coding block to the
coordinates of the reference block in the same decoded slice
3.20
byte
sequence of 8 bits, within which, when written or read as a sequence of bit values, the left-most and right-
most bits represent the most and least significant bits, respectively
3.21
byte-aligned
positioned an integer multiple of 8 bits from the position of the first bit in the bitstream
3.22
byte-aligned
position at which it appears in a bitstream is byte-aligned
© ISO/IEC 2026 – All rights reserved
3.23
byte stream
encapsulation of a NAL unit stream into a series of bytes containing start code prefixes and NAL units
3.24
chroma
sample array or single sample representing one of the two colour difference signals related to the primary
colours, represented by the symbols Cb and Cr
Note 1 to entry: The term chroma is used rather than the term chrominance in order to avoid the implication of the use
of linear light transfer characteristics that is often associated with the term chrominance.
3.25
CRA picture
IRAP picture for which each VCL NAL unit has nal_unit_type equal to CRA_NUT
Note 1 to entry: A CRA picture does not use inter prediction in its decoding process, and could be the first picture in the
bitstream in decoding order, or could appear later in the bitstream. A CRA picture could have associated RADL or RASL
pictures. When a CRA picture has NoOutputBeforeRecoveryFlag equal to 1, the associated RASL pictures are not output
by the decoder, because they might not be decodable, as they could contain references to pictures that are not present in
the bitstream.
3.26
CRA PU
PU in which the coded picture is a CRA picture
3.27
CRA subpicture
IRAP subpicture for which each VCL NAL unit has nal_unit_type equal to CRA_NUT
3.28
coded layer video sequence:
sequence of PUs with the same value of nuh_layer_id that consists, in decoding order, of a CLVSS PU, followed
by zero or more PUs that are not CLVSS PUs, including all subsequent PUs up to but not including any
subsequent PU that is a CLVSS PU
Note 1 to entry: A CLVSS PU could be an IDR PU, a CRA PU, or a GDR PU. The value of NoOutputBeforeRecoveryFlag is
equal to 1 for each IDR PU, and each CRA PU that has HandleCraAsClvsStartFlag equal to 1, and each CRA or GDR PU that
is the first PU in the layer of the bitstream in decoding order or the first PU in the layer of the bitstream that follows an
EOS NAL unit in the layer in decoding order.
3.29
CLVSS PU
PU in which the coded picture is a CLVSS picture
3.30
CLVSS picture
coded picture that is an IRAP picture with NoOutputBeforeRecoveryFlag equal to 1 or a GDR picture with
NoOutputBeforeRecoveryFlag equal to 1
3.31
coded picture
coded representation of a picture comprising VCL NAL units with a particular value of nuh_layer_id within an
AU and containing all CTUs of the picture
3.32
coded picture buffer
first-in first-out buffer containing DUs in decoding order specified in the hypothetical reference decoder
© ISO/IEC 2026 – All rights reserved
Note 1 to entry: The hypothetical reference decoder is specified in Annex C.
3.33
coded representation
data element as represented in its coded form
3.34
coded slice NAL unit
NAL unit that contains a coded slice
3.35
coded video sequence
sequence of AUs that consists, in decoding order, of a CVSS AU, followed by zero or more AUs that are not
CVSS AUs, including all subsequent AUs up to but not including any subsequent AU that is a CVSS AU
3.36
CVSS AU
IRAP AU or GDR AU for which the coded picture in each PU is a CLVSS picture
3.37
coding block
MxN block of samples for some values of M and N such that the division of a CTB into coding blocks is a
partitioning
3.38
coding tree block
N×N block of samples for some value of N such that the division of a component into CTBs is a partitioning
3.39
coding tree unit
CTB of luma samples, two corresponding CTBs of chroma samples of a picture that has three sample arrays,
or a CTB of samples of a monochrome picture, and syntax structures used to code the samples
3.40
coding unit
coding block of luma samples, two corresponding coding blocks of chroma samples of a picture that has three
sample arrays in the single tree mode, or a coding block of luma samples of a picture that has three sample
arrays in the dual tree mode, or two coding blocks of chroma samples of a picture that has three sample
arrays in the dual tree mode, or a coding block of samples of a monochrome picture, and syntax structures
used to code the samples
3.41
component
array or single sample from one of the three arrays (luma and two chroma) that compose a picture in 4:2:0,
4:2:2, or 4:4:4 colour format or the array or a single sample of the array that compose a picture in
monochrome format
3.42
context variable
variable specified for the adaptive binary arithmetic decoding process of a bin by a formula containing
recently decoded bins
3.43
deblocking filter
filtering process that is applied as part of the decoding process in order to minimize the appearance of visual
artefacts at the boundaries between blocks
© ISO/IEC 2026 – All rights reserved
3.44
decoded picture
picture produced by applying the decoding process to a coded picture
3.45
decoded picture buffer
buffer holding decoded pictures for reference, output reordering, or output delay specified for the
hypothetical reference decoder
3.46
decoder
embodiment of a decoding process
3.47
decoding order
order in which syntax elements are processed by the decoding process
3.48
decoding process
process specified in this document that reads a bitstream and derives decoded pictures from it
3.49
decoding unit
AU if DecodingUnitHrdFlag is equal to 0 or a subset of an AU otherwise, consisting of one or more VCL NAL
units in an AU and the associated non-VCL NAL units
3.50
emulation prevention byte
byte equal to 0x03 that is present within a NAL unit when the syntax elements of the bitstream form certain
patterns of byte values in a manner that ensures that no sequence of consecutive byte-aligned bytes in the
NAL unit can contain a start code prefix
3.51
encoder
embodiment of an encoding process
3.52
encoding process
process not specified in this document that produces a bitstream conforming to this document
3.53
filler data NAL units
NAL units with nal_unit_type equal to FD_NUT
3.54
flag
variable or single-bit syntax element that can take one of the two possible values: 0 and 1
3.55
frequency index
one-dimensional or two-dimensional index associated with a transform coefficient prior to the application of
a transform in the decoding process
3.56
GDR AU
© ISO/IEC 2026 – All rights reserved
AU in which there is a PU for each layer present in the CVS and the coded picture in each present PU is a GDR
picture
3.57
GDR PU
PU in which the coded picture is a GDR picture
3.58
GDR picture
picture for which each VCL NAL unit has nal_unit_type equal to GDR_NUT
Note 1 to entry: The value of pps_mixed_nalu_types_in_pic_flag for a GDR picture is equal to 0. When
pps_mixed_nalu_types_in_pic_flag is equal to 0 for a picture, and any slice of the picture has nal_unit_type equal to
GDR_NUT, all other slices of the picture have the same value of nal_unit_type, and the picture is known to be a GDR picture
after receiving the first slice.
3.59
GDR subpicture
subpicture for which each VCL NAL unit has nal_unit_type equal to GDR_NUT
3.60
hypothetical reference decoder
hypothetical decoder model that specifies constraints on the variability of conforming NAL unit streams or
conforming byte streams that an encoding process may produce
3.61
hypothetical stream scheduler
hypothetical delivery mechanism used for checking the conformance of a bitstream or a decoder with
regards to the timing and data flow of the input of a bitstream into the hypothetical reference decoder
3.62
IDR picture
IRAP picture for which each VCL NAL unit has nal_unit_type equal to IDR_W_RADL or IDR_N_LP
Note 1 to entry: An IDR picture does not use inter prediction in its decoding process, and could be the first picture in the
bitstream in decoding order, or could appear later in the bitstream. Each IDR picture is the first picture of a CVS in
decoding order. When an IDR picture for which each VCL NAL unit has nal_unit_type equal to IDR_W_RADL, it could have
associated RADL pictures. When an IDR picture for which each VCL NAL unit has nal_unit_type equal to IDR_N_LP, it does
not have any associated leading pictures. An IDR picture does not have associated RASL pictures.
3.63
IDR PU
PU in which the coded picture is an IDR picture
3.64
IDR subpicture
IRAP subpicture for which each VCL NAL unit has nal_unit_type equal to IDR_W_RADL or IDR_N_LP
3.65
inter coding
coding of a coding block, slice, or picture that uses inter prediction
3.66
inter-layer reference picture
picture in the same AU with the current picture, with nuh_layer_id less than the nuh_layer_id of the current
picture, and is marked as "used for long-term reference"
3.67
inter prediction
© ISO/IEC 2026 – All rights reserved
prediction derived from blocks of sample values of one or more reference pictures as determined by motion
vectors
3.68
intra block copy prediction
prediction derived from blocks of sample values of the same decoded slice as determined by block vectors
3.69
intra coding
coding of a coding block, slice, or picture that uses intra prediction
3.70
intra prediction
prediction derived from neighbouring sample values of the same decoded slice
3.71
IRAP AU
AU in which there is a PU for each layer present in the CVS and the coded picture in each PU is an IRAP picture
3.72
IRAP picture
coded picture for which all VCL NAL units have the same value of nal_unit_type in the range of IDR_W_RADL
to CRA_NUT, inclusive
Note 1 to entry: An IRAP picture could be a CRA picture or an IDR picture. An IRAP picture does not use inter prediction
from reference pictures in the same layer in its decoding process. The first picture in the bitstream in decoding order is
an IRAP or GDR picture. For a single-layer bitstream, provided the necessary parameter sets are available when they
need to be referenced, the IRAP picture and all subsequent non-RASL pictures in the CLVS in decoding order are correctly
decodable without performing the decoding process of any pictures that precede the IRAP picture in decoding order.
Note 2 to entry: The value of pps_mixed_nalu_types_in_pic_flag for an IRAP picture is equal to 0. When
pps_mixed_nalu_types_in_pic_flag is equal to 0 for a picture, and any sli
...