ISO/IEC 23008-9:2023

Information technology - High efficiency coding and media delivery in heterogeneous environments - Part 9: 3D Audio conformance testing

This document specifies conformance criteria for both bitstreams and decoders compliant with the MPEG-H 3D audio standard as defined in ISO/IEC 23008-3. This is done to assist implementers and to ensure interoperability.

Technologies de l'information — Codage à haut rendement et fourniture de supports dans les environnements hétérogènes — Partie 9: Essais de conformité 3D Audio

General Information

• Status: Published
• Publication Date: 14-May-2023
• 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 - Coding of audio, picture, multimedia and hypermedia information
• Current Stage: 6060 - International Standard published
• Start Date: 15-May-2023
• Due Date: 16-Jun-2024
• Completion Date: 15-May-2023

Relations

• Revises: ISO/IEC 23008-9:2022 - Information technology - High efficiency coding and media delivery in heterogeneous environments - Part 9: 3D Audio conformance testing
• Effective Date: 24-Dec-2022

Overview

ISO/IEC 23008-9:2023 - "Information technology - High efficiency coding and media delivery in heterogeneous environments - Part 9: 3D Audio conformance testing" specifies conformance criteria for MPEG‑H 3D audio bitstreams and decoders (as defined in ISO/IEC 23008-3). Published May 2023 (3rd edition), this standard helps implementers validate implementations, ensure interoperability, and provide repeatable test methods for product qualification and certification.

Key topics and technical scope

The standard defines technical requirements, test procedures and test assets for MPEG‑H 3D audio conformance testing. Major technical topics include:

• Conformance framework and profiles
  • Test profiles, naming conventions, and general conformance procedures.
• Bitstream structure and characteristics
  • Descriptions of configuration elements (e.g., mpegh3daConfig(), FrameworkConfig3d(), Signals3d(), SpeakerConfig3d()) and how they are validated.
• Core audio and frame elements
  • Core configuration (mpegh3daDecoderConfig(), mpegh3daCoreConfig()), frame structures (mpegh3daFrame(), channel elements) and expected behaviors.
• Advanced audio features
  • Object metadata and EnhancedObjectMetadataConfig, dynamic range control (uniDrc), AudioPreRoll, and object‑based metadata frames.
• Spatial and rendering technologies
  • MPEG Surround/SpatialSpecificConfig, SAOC and SAOC 3D configuration and frames, HOA/ambisonics related configuration.
• Conformance tooling and test artefacts
  • Conformance test tools, test procedures, naming conventions and recommended test cases for bitstreams and decoders.

Practical applications and users

ISO/IEC 23008-9:2023 is intended for professionals who develop, test or certify immersive audio workflows:

• Codec implementers and decoder developers - to validate compliance with MPEG‑H 3D audio bitstream and decoder behavior.
• Device manufacturers (TVs, set‑top boxes, AV receivers, mobile/VR devices) - to ensure correct rendering and interoperability with content providers.
• Broadcasters and streaming services - to verify delivered streams meet conformance criteria and behave consistently across receivers.
• Test labs and certification bodies - to create reproducible test suites and certification programs.
• Content creators and post‑production houses - to confirm exported bitstreams will play back as intended on compliant decoders.

Why it matters (SEO keywords)

Conformance testing specified in ISO/IEC 23008-9:2023 enables consistent MPEG‑H 3D audio playback, reliable 3D audio conformance, and verified bitstream and decoder conformance-key for interoperability across streaming platforms, broadcast chains, and consumer devices supporting immersive audio.

Related standards

• ISO/IEC 23008-3 - MPEG‑H 3D audio (reference normative source for the conformance criteria)

For implementers, this standard is a practical reference for designing conformance test suites, debugging interoperability issues, and certifying MPEG‑H 3D audio implementations.

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 23008-9
Third edition
2023-05
Information technology — High
efficiency coding and media delivery
in heterogeneous environments —
Part 9:
3D Audio conformance testing
Technologies de l'information — Codage à haut rendement et
fourniture de supports dans les environnements hétérogènes —
Partie 9: Essais de conformité 3D Audio
Reference number
© ISO/IEC 2023
© ISO/IEC 2023
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
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© ISO/IEC 2023 – All rights reserved

Contents Page
Foreword .vii
Introduction .viii
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviated terms . 1
3.1 Terms and definitions . 1
3.2 Abbreviated terms . 2
4 MPEG-H 3D audio conformance testing . 3
4.1 General . 3
4.2 Profiles . 3
4.3 Test procedure . 3
4.3.1 General . 3
4.3.2 Naming convention . 4
4.3.3 Conformance test tools . 6
5 MPEG-H 3D audio bitstreams . 7
5.1 Characteristics, test procedure . 7
5.2 MPEG-H 3D audio general configuration . 7
5.2.1 mpegh3daConfig() . 7
5.2.2 FrameworkConfig3d() . 7
5.2.3 Signals3d() . . 7
5.2.4 SpeakerConfig3d() . 8
5.2.5 mpegh3daFlexibleSpeakerConfig(). 8
5.2.6 mpegh3daSpeakerDescription() . . 8
5.3 MPEG-H 3D core audio configuration . 8
5.3.1 mpegh3daDecoderConfig() . 8
5.3.2 mpegh3daSingleChannelElementConfig() . 8
5.3.3 mpegh3daChannelPairElementConfig() . 9
5.3.4 mpegh3daCoreConfig() . 9
5.3.5 mpegh3daLfeElementConfig() . 9
5.3.6 mpegh3daExtElementConfig() . 9
5.3.7 mpegh3daConfigExtension() . 10
5.3.8 SbrConfig() . 10
5.3.9 Mps212Config() . . 10
5.4 MPEG-H 3D core audio frame . 11
5.4.1 mpegh3daFrame() . 11
5.4.2 mpegh3daSingleChannelElement() . 11
5.4.3 mpegh3daChannelPairElement() . 11
5.4.4 mpegh3daLfeElement() . 11
5.4.5 mpegh3daExtElement() . 11
5.4.6 ics_info() .12
5.4.7 mpegh3daCoreCoderData() .12
5.4.8 StereoCoreToolInfo() .12
5.4.9 fd_channel_stream() . 13
5.4.10 lpd_channel_stream(). 13
5.4.11 acelp_coding() . 14
5.4.12 tcx_coding () . 14
5.4.13 lpd_stereo_stream() .15
5.4.14 igf_stereo_pred_data(). 15
5.4.15 igf_data() . 15
5.4.16 tbe_data() . 15
5.4.17 tw_data() . 16
5.4.18 scale_factor_data() . 16
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5.4.19 tns_data() . 16
5.4.20 ac_spectral_data() . 16
5.4.21 arith_data() . 16
5.4.22 fac_data() . 16
5.4.23 code_book_indices() . 16
5.4.24 UsacSbrData() . 16
5.4.25 Mps212Data() . 16
5.5 Fill element . . 17
5.6 MPEG surround configuration, SpatialSpecificConfig(). 17
5.7 MPEG surround frame, SpatialFrame() . 17
5.8 SAOC configuration, SAOCSpecificConfig() . 17
5.9 SAOC frame, SAOCFrame() . 17
5.10 AudioPreRoll . 17
5.10.1 Recursive presence of AudioPreRoll extension payload . 17
5.10.2 AudioPreRoll() . 17
5.11 Dynamic range control configuration . 17
5.11.1 mpegh3daUniDrcConfig() . 17
5.11.2 mpegh3daUniDrcChannelLayout(). 18
5.11.3 drcCoefficientsUniDrc() . 18
5.11.4 drcInstructionsUniDrc() . 18
5.11.5 uniDrcConfigExtension() . 18
5.12 Dynamic range control frame, uniDrcGain() . 18
5.13 Object metadata configuration, ObjectMetadataConfig() . 18
5.14 Object metadata frame . 18
5.14.1 object_metadata_efficient() . 18
5.14.2 object_metadata() . 18
5.14.3 object_metadata_efficient() . 19
5.14.4 intracoded_object_metadata_efficient() . 19
5.14.5 differential_object_metadata() . 20
5.14.6 offset_data() . 21
5.14.7 object_metadata_low_delay() . 21
5.14.8 intracoded_object_metadata_low_delay() . 21
5.14.9 dynamic_object_metadata() . 22
5.14.10 single_dynamic_object_metadata() . 22
5.15 EnhancedObjectMetadataConfig() . 23
5.16 EnhancedObjectMetadataFrame() . 24
5.17 SAOC 3D Config . 24
5.17.1 SAOC3DSpecificConfig() . 24
5.17.2 SAOC3DgetNumChannels() . 25
5.17.3 SAOC3DExtensionConfig() . 25
5.17.4 SAOC3DExtensionConfigData() . 25
5.17.5 SAOCExtensionConfig() .25
5.18 SAOC 3D frame . 25
5.18.1 Saoc3DFrame() . 25
5.18.2 SAOC3DFramingInfo() . 26
5.18.3 EcDataSaoc() . . .26
5.18.4 ByteAlign() .26
5.18.5 SAOC3DExtensionFrame() . 26
5.18.6 SAOC3DExtensionFrameData() . 26
5.18.7 SAOCExtensionFrame() . 26
5.18.8 HOAConfig() .26
5.18.9 HOADecoderConfig() . 26
5.18.10 HOAEnhConfig() . 27
5.18.11 HOADecoderEnhConfig () . 27
5.18.12 getSubbandWidths () . 27
5.19 HOA frame.28
5.19.1 HOAFrame() .28
5.19.2 HOAEnhFrame () .28
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© ISO/IEC 2023 – All rights reserved

5.19.3 ChannelSideInfoData() .28
5.19.4 AddAmbHoaInfoChannel() .28
5.19.5 HOAGainCorrectionData() .28
5.19.6 VVectorData() .29
5.19.7 HOAPredictionInfo() .29
5.19.8 HOADirectionalPredictionInfo() .29
5.19.9 readDirPredDiffValues() .30
5.19.10 HOAParInfo () .30
5.19.11 readParDiffValues () .30
5.20 FMT converter frame, FormatConverterFrame() .30
5.21 Multi-channel coding tool config, MCTConfig () .30
5.22 Multi-channel coding tool frame . 30
5.22.1 MultichannelCodingBoxRotation () .30
5.22.2 MultichannelCodingBoxPrediction () . 31
5.22.3 MultichannelCodingFrame() . 31
5.23 Tonal component coding configuration, TccConfig () . 32
5.24 Tonal component coding frame . 32
5.24.1 General . 32
5.24.2 TccGroupOfSegments() . 32
5.25 HREP config, HREPConfig() . 32
5.26 HREP frame, HREPFrame() .33
5.27 ICG config, ICGConfig () .33
5.28 SignalGroupInformation Config, SignalGroupInformation () . 33
5.29 DownmixMatrix . 33
5.29.1 downmixConfig() . 33
5.29.2 DownmixMatrixSet() . 33
5.29.3 DownmixMatrix() .34
5.29.4 DecoderGainValue() .34
5.29.5 ReadRange() . 35
5.29.6 EqualizerConfig() . 35
5.30 Loudness info . 35
5.30.1 mpegh3daLoudnessInfoSet() . 35
5.30.2 loudnessInfo() . 35
5.30.3 loudnessInfoSetExtension() . 35
5.31 Audioscene info . 36
5.31.1 mae_AudioSceneInfo . .36
5.31.2 mae_Data() . 36
5.31.3 mae_GroupDefinition() . . 36
5.31.4 mae_SwitchGroupDefinition() . 37
5.31.5 mae_Description() . 37
5.31.6 mae_ContentData() . 37
5.31.7 mae_CompositePair() .38
5.31.8 mae_GroupPresetDefinition() .38
5.31.9 mae_ProductionScreenSizeData() .39
5.31.10 mae_LoudnessCompensationData () .39
5.31.11 mae_ProductionScreenSizeDataExtension() .39
5.31.12 mae_GroupPresetDefinitionExtension() .40
5.31.13 mae_DrcUserInterfaceInfo() .40
5.32 HOA matrix . 41
5.32.1 HoaRenderingMatrixSet() . 41
5.32.2 HoaRenderingMatrix() . 41
5.32.3 DecoderHoaMatrixData() . 42
5.32.4 DecoderHoaGainValue() . 42
5.33 CompatibleProfileLevelSet(). 42
5.34 Restrictions depending on profiles and levels . 42
5.34.1 General . 42
5.34.2 Low complexity profile . 42
6 MPEG-H 3D audio interfaces to the MPEG-H 3D audio decoder .46
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6.1 Characteristics and test procedure .46
6.2 Interface for local setup information .46
6.2.1 mpegh3daLocalSetupInformation().46
6.2.2 LoudspeakerRendering() .46
6.2.3 BinauralRendering() . 47
6.2.4 LocalScreenSizeInformation() . . 47
6.3 Interface for user interaction . 47
6.3.1 mpegh3daElementInteraction() . 47
6.3.2 ElementInteractionData () . 47
6.3.3 ei_GroupInteractivityStatus () .48
6.3.4 LocalZoomAreaSize() .48
6.4 Interface for loudness normalization and dynamic range control .48
6.5 Interface for scene displacement data, mpegh3daSceneDisplacementData() .48
6.6 Interface for positional scene displacement data,
mpegh3daPositionalSceneDisplacementData() .48
7 MPEG-H 3D audio decoders .49
7.1 General .49
7.2 Basic conformance test conditions .49
7.2.1 Element configuration test condition .49
7.2.2 Sampling rate. 51
7.2.3 Core mode tests [Fd|Lpd|Cct] . 52
7.3 Additional test conditions . 52
7.3.1 3D audio core (FD) . 52
7.3.2 3D audio core (LPD) .60
7.3.3 3D audio core (FD and LPD) .64
7.3.4 Object rendering . 71
7.3.5 Higher order ambisonics (HOA) .74
7.3.6 Signalling of HOA rendering matrix [Hmx] . 78
7.3.7 Downmix matrix test condition (dwx) . 78
7.3.8 Dynamic range and loudness control .80
7.3.9 AudioPreRoll() condition, immediate playout frame (IPF) .84
7.4 Decoder settings .85
7.4.1 Target layout (Lay-) .85
7.4.2 Target loudness (Lou-) .86
7.4.3 DRC effect type request (Eff-) .87
7.4.4 Group preset request (Pr-) .87
7.4.5 Conformance point (Cpo-) .88
Bibliography .89
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© ISO/IEC 2023 – All rights reserved

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).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents) or the IEC
list of patent declarations received (see https://patents.iec.ch).
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.
This third edition cancels and replaces the second edition (ISO/IEC 23008-9:2022) which has been
technically revised.
The main changes are as follows:
— Sample rate conversion.
A list of all parts in the ISO 23008 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.
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© ISO/IEC 2023 – All rights reserved

Introduction
This document specifies how tests can be designed to verify whether bitstreams and decoders meet
the requirements as specified in ISO/IEC 23008-3 and allow interoperability with remote terminals in
interactive, broadcast, streaming and local (with stored contents) sessions. These tests can be used for
various purposes, such as:
— manufacturers of encoders, and their customers, can use the tests to verify whether the encoder
produces bitstreams compliant with ISO/IEC 23008-3,
— manufacturers of decoders and their customers can use the tests to verify whether the decoder
meets the requirements specified in ISO/IEC 23008-3 for the claimed decoder capabilities,
— manufacturers and customers of terminals supporting interactive, broadcast, streaming, and local
sessions over a multitude of transport protocols and networks, can use the tests to verify whether
the claimed functionalities are compliant with ISO/IEC 23008-3,
— manufacturers of test equipment, and their customers can use the tests to verify compliance with
ISO/IEC 23008-3.
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© ISO/IEC 2023 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 23008-9:2023(E)
Information technology — High efficiency coding and
media delivery in heterogeneous environments —
Part 9:
3D Audio conformance testing
1 Scope
This document specifies conformance criteria for both bitstreams and decoders compliant with the
MPEG-H 3D audio standard as defined in ISO/IEC 23008-3. This is done to assist implementers and to
ensure interoperability.
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 23003-1, Information technology — MPEG audio technologies — Part 1: MPEG Surround
ISO/IEC 23003-2, Information technology — MPEG audio technologies — Part 2: Spatial Audio Object
Coding (SAOC)
ISO/IEC 23003-3:2020, Information technology — MPEG audio technologies — Part 3: Unified speech and
audio coding
ISO/IEC 23003-4:2020, Information technology — MPEG audio technologies — Part 4: Dynamic range
control
ISO/IEC 23008-3:2022, Information technology — High efficiency coding and media delivery in
heterogeneous environments — Part 3: 3D audio
ISO/IEC 23091-3, Information technology — Coding-independent code points — Part 3: Audio
3 Terms, definitions and abbreviated terms
3.1 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/
3.1.1
bitstream
encoded audio data
3.1.2
conformance test bitstream
MPEG-H 3DA encoded bitstream used for testing the conformance of a MPEG-H 3DA decoder
© ISO/IEC 2023 – All rights reserved

3.1.3
conformance test case
combination of one or more conformance test conditions for which one conformance test bitstream is
provided
3.1.4
conformance test condition
condition which applies to properties of a conformance test bitstream in order to test a certain
functionality of the MPEG-H 3DA decoder
3.1.5
conformance test criteria
one or more conformance test tools with requirements that define whether a given output from a
decoder under test fulfils the conformance
3.1.6
conformance test data
conformance test sequences and conformance criteria
3.1.7
conformance test sequences
generic term for conformance test bitstream and decoder settings with a corresponding reference
3.1.8
conformance test tool
tool to compare the reference waveform with the output from a decoder under test
3.1.9
decoder setting case
combination of one or more decoder setting conditions to trigger specific settings of the decoder
3.1.10
decoder setting condition
condition applied to the decoder behaviour in order to test functionality of the MPEG-H 3DA decoder
3.1.11
reference waveform
decoded counterpart of a conformance test bitstream with specific decoder settings
3.2 Abbrevi
...