ISO/IEC 23090-16:2025

Information technology - Coded representation of immersive media - Part 16: Reference software for versatile video coding

This document provides reference software for Rec. ITU-T H.266 | ISO/IEC 23090-3. The reference software includes both encoder and decoder functionality. Reference software is useful in aiding users of a video coding standard to establish and test conformance and interoperability, and to educate users and demonstrate the capabilities of the standard. For these purposes, the accompanying software is provided as an aid for the study and implementation of Rec. ITU-T H.266 | ISO/IEC 23090-3.

Technologies de l'information — Représentation codée de média immersifs — Partie 16: Logiciel de référence pour le codage vidéo polyvalent (VCC)

General Information

• Status: Published
• Publication Date: 19-Nov-2025
• 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: 20-Nov-2025
• Due Date: 22-Jul-2026
• Completion Date: 20-Nov-2025

Relations

• Revises: ISO/IEC 23090-16:2022 - Information technology - Coded representation of immersive media - Part 16: Reference software for versatile video coding
• Effective Date: 17-Aug-2024

Overview

ISO/IEC 23090-16:2025 - "Information technology - Coded representation of immersive media - Part 16: Reference software for versatile video coding" - provides the official reference software package for Rec. ITU‑T H.266 | ISO/IEC 23090-3 (Versatile Video Coding, VVC). The document includes both a reference encoder and decoder (referred to as the VTM software package) and is intended as an aid for study, implementation, conformance testing and interoperability verification. The software and accompanying specification are available from the ISO standards portal.

Key Topics

• Reference implementation: A packaged encoder and decoder (VTM) illustrating the decoding and encoding processes defined in Rec. ITU‑T H.266 / ISO/IEC 23090‑3.
• Supported profiles: Main 10, Main 10 Still Picture, Main 10 4:4:4, various multilayer and Main 12/Main 16 profiles and still-picture variants (profiles listed in the standard).
• Supplemental enhancement information (SEI): Support for SEI messages specified in Rec. ITU‑T H.266 and Rec. ITU‑T H.274 / ISO/IEC 23002‑7, including encoding/parsing and export of associated data.
• Conformance and interoperability: Tools and behavior intended to help test bitstream conformance and decoder conformity to H.266 decoding processes.
• Software updates: The 2025 second edition updates include additional SEI implementations, bug fixes, runtime improvements and modified encoder configurations for improved compression performance.
• Limitations & legal: The standard notes that reference software is illustrative; conformance requirements in the base VVC specification take precedence. Standard includes warranty disclaimers for the provided software.

Applications

• Codec implementers and integrators: Use the reference encoder/decoder as a starting point for development or to validate implementation behavior against VVC/H.266.
• Quality assurance and interoperability labs: Generate and decode test bitstreams to verify conformance and interoperability across devices and software.
• Researchers and educators: Study algorithms, SEI handling and encoder options to understand VVC features and behavior.
• Content providers and device manufacturers: Evaluate encoding quality and bitstream features supported by VVC profiles supported in the reference software.

Related standards

• Rec. ITU‑T H.266 (2023) / ISO/IEC 23090‑3:2024 - Versatile Video Coding (VVC) - normative basis for this reference software.
• Rec. ITU‑T H.274 / ISO/IEC 23002‑7 - Versatile supplemental enhancement information messages - referenced for SEI support.

Keywords: ISO/IEC 23090-16:2025, reference software, VVC, H.266, VTM, encoder, decoder, conformance testing, interoperability, SEI messages.

Standards Content (Sample)

International
Standard
ISO/IEC 23090-16
Second edition
Information technology — Coded
2025-11
representation of immersive media —
Part 16:
Reference software for versatile
video coding
Technologies de l'information — Représentation codée de média
immersifs —
Partie 16: Logiciel de référence pour le codage vidéo
polyvalent (VCC)
Reference number
© ISO/IEC 2025
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 2025 – All rights reserved
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Conventions . 2
6 Reference software for Rec. ITU-T H.266 | ISO/IEC 23090-3 . 2
Bibliography . 3

© ISO/IEC 2025 – All rights reserved
iii
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 not
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 Rec. ITU-T H.266.2).
This second edition cancels and replaces the first edition (ISO/IEC 23090-16:2022), which has been
technically revised.
The main changes are as follows:
— Inclusion of software implementation of additional SEI messages defined in Rec. ITU-T H.266 |
ISO/IEC 23090-3 and in Rec. ITU-T H.274 | ISO/IEC 23002-7.
— General software improvements such as bug fixes, run time improvements, and additional encoder
configuration options.
— Modified encoder configuration files yielding improved compression performance.
A list of all parts in the ISO/IEC 23090 series can be found on the ISO and IEC websites.
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 2025 – All rights reserved
iv
Introduction
0.1  General
This document provides reference software for Rec. ITU-T H.266 | ISO/IEC 23090-3. The reference software
includes both encoder and decoder functionality.
Reference software is useful in aiding users of a video coding standard to establish and test conformance
and interoperability, and to educate users and demonstrate the capabilities of the standard. For these
purposes, the accompanying software is provided as an aid for the study and implementation of Rec. ITU-T
H.266 | ISO/IEC 23090-3.
0.2  Purpose
The purpose of this document is to provide the following:
— Reference decoder software capable of decoding bitstreams that conform to Rec. ITU-T H.266 |
ISO/IEC 23090-3 in a manner that conforms to the decoding process specified in Rec. ITU-T H.266 |
ISO/IEC 23090-3.
— Reference encoder software capable of producing bitstreams that conform to Rec. ITU-T H.266 |
ISO/IEC 23090-3.
0.3  Examples of use
Some examples of uses that can be appropriate for the reference decoder software are as follows:
— As an illustration of how to perform the de
...