ISO/IEC 23003-6:2022

INTERNATIONAL ISO/IEC
STANDARD 23003-6
First edition
2022-08
Information technology — MPEG
audio technologies —
Part 6:
Unified speech and audio coding
reference software
Technologies de l'information — Technologies audio MPEG —
Partie 6: Logiciel de référence pour le codage unifié parole et audio
Reference number
© ISO/IEC 2022
© ISO/IEC 2022
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© ISO/IEC 2022 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Reference software structure .1
4.1 General . 1
4.2 Copyright disclaimer for software modules . 2
5 Bitstream decoding software .3
5.1 General . 3
5.2 USAC decoding software . 3
Annex A (informative) Bitstream encoding software . 4
Annex B (informative) Additional utility software . 5
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© ISO/IEC 2022 – All rights reserved

Foreword
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Commission) form the specialized system for worldwide standardization. National bodies that are
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www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information.
A list of all parts in the ISO/IEC 23003 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
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© ISO/IEC 2022 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 23003-6:2022(E)
Information technology — MPEG audio technologies —
Part 6:
Unified speech and audio coding reference software
1 Scope
This document contains simulation software for the Unified speech and audio coding standard as
defined in ISO/IEC 23003-3.
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 23003-3, Information technology — MPEG audio technologies — Part 3: Unified speech and audio
coding
3 Terms and definitions
No terms and definitions are listed in this document.
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/
4 Reference software structure
4.1 General
This software has been derived from reference models used in the process of developing of
ISO/IEC 23003-3.
Reference software is normative in the sense that it correctly implements the USAC decoding processes
described in ISO/IEC 23003-3. Complying ISO/IEC 23003-3 implementations are not expected to follow
the algorithms or the programming techniques used by the reference software. Although the decoding
software is considered normative, it cannot add anything to the textual technical description of USAC
included in ISO/IEC 23003-3.
The software contained in this document is divided into several categories:
a) Bitstr
...