IEC 61937-10:2017

Digital audio - Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 - Part 10: Non-linear PCM bitstreams according to the MPEG-4 audio lossless coding (ALS) format

IEC 61937-10:2017(E) specifies the method for IEC 60958 to convey non-linear PCM bitstreams encoded in accordance with the MPEG-4 audio lossless coding (ALS) format.
This second edition cancels and replaces the first edition published in 2011. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) Addition of Levels 2, 3, 4 of MPEG-4 ALS Simple Profile;
b) Addition of data-type bits 0-4 and data-type bits 5-6 for MPEG-4 ALS with LATM/LOAS header.

General Information

• Status: Published
• Publication Date: 27-Jul-2017
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 33.160.30 - Audio systems
• ICS: 35.240.99 - IT applications in other fields
• Technical Committee: TA 20 - Analogue and digital audio
• Drafting Committee: MT 61937-10 - TC 100/MT 61937-10
• Current Stage: PPUB - Publication issued
• Start Date: 04-Aug-2017
• Completion Date: 28-Jul-2017

Relations

• Revises: IEC 61937-10:2011 - Digital audio - Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 - Part 10: Non-linear PCM bitstreams according to the MPEG-4 audio lossless coding (ALS) format
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61937-10 ®
Edition 2.0 2017-07
INTERNATIONAL
STANDARD
Digital audio – interface for non-linear PCM encoded audio bitstreams applying
IEC 60958 –
Part 10: Non-linear PCM bitstreams according to the MPEG-4 audio lossless
coding (ALS) format
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IEC 61937-10 ®
Edition 2.0 2017-07
INTERNATIONAL
STANDARD
Digital audio – interface for non-linear PCM encoded audio bitstreams applying

IEC 60958 –
Part 10: Non-linear PCM bitstreams according to the MPEG-4 audio lossless

coding (ALS) format
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.160.30; 35.240.99 ISBN 978-2-8322-4560-6

– 2 – IEC 61937-10:2017 © IEC 2017

CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions, abbreviated terms and conventions . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms . 7
3.3 Presentation convention . 7
4 Mapping of the audio bitstream onto IEC 61937 . 7
4.1 General . 7
4.2 MPEG-4 ALS burst-info . 7
5 Format of MPEG-4 ALS data-bursts . 8
5.1 General . 8
5.2 Audio data-bursts . 9
5.2.1 Data-burst for MPEG-4 ALS . 9
5.2.2 Latency of MPEG-4 ALS decoding . 10
5.2.3 Data-burst for MPEG-4 ALS in LATM/LOAS . 12
Annex A (informative) Effect of repetition period of data-burst and IEC 60958 frame
rate on frame period for the MPEG-4 ALS bitstreams . 13
Annex B (normative) Burst payload format for MPEG-4 ALS . 14
Annex C (normative) Values for ALSSpecificConfig in the MPEG-4 ALS burst payload
format . 15
Annex D (informative) Example use case of the ALS simple profile in LATM/LOAS . 17

Figure 1 – MPEG-4 ALS data-burst . 9
Figure 2 – Latency of MPEG-4 ALS decoding . 11
Figure 3 – The MPEG-4 ALS burst-payload . 11
Figure 4 – MPEG-4 ALS burst-payload with LATM/LOAS header . 12
Figure B.1 – MPEG-4 ALS burst-payload . 14

Table 1 – Fields of burst-info (data-type bits 0-4=23, data-type bits 5-6=0/ data-type
bits 0-4=25, data-type bits 5-6=2) . 8
Table 2 – Sampling frequency, multiplier, and IEC 60958 frame rate . 10
Table A.1 – MPEG-4 ALS payload and frame repetition: some examples . 13
Table C.1 – Recommended values for the ALSSpecificConfig in the MPEG-4 ALS
burst-payload . 15
Table D.1 – MPEG-4 ALS simple profile, maximum payload size and frame repetition:
some examples . 17

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIGITAL AUDIO – INTERFACE FOR NON-LINEAR PCM ENCODED
AUDIO BITSTREAMS APPLYING IEC 60958 –

Part 10: Non-linear PCM bitstreams according to the MPEG-4 audio
lossless coding (ALS) format
FOREWORD
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International Standard IEC 61937-10 has been prepared by technical area 4: Digital system
interfaces and protocols, of IEC technical committee 100: Audio, video and multimedia
systems and equipment.
This second edition cancels and replaces the first edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Addition of Levels 2, 3, 4 of MPEG-4 ALS Simple Profile;
b) Addition of data-type bits 0-4 and data-type bits 5-6 for MPEG-4 ALS with LATM/LOAS
header.
– 4 – IEC 61937-10:2017 © IEC 2017

The text of this International Standard is based on the following documents:
CDV Report on voting
100/2630/CDV 100/2930/RVC
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 61937 series, published under the general title Digital audio –
Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 can be found on
the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

DIGITAL AUDIO – INTERFACE FOR NON-LINEAR PCM ENCODED
AUDIO BITSTREAMS APPLYING IEC 60958 –

Part 10: Non-linear PCM bitstreams according to the MPEG-4 audio
lossless coding (ALS) format
1 Scope
This part of IEC 61937 specifies the method for IEC 60958 to convey non-linear PCM
bitstreams encoded in accordance with the MPEG-4 audio lossless coding (ALS) format.
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.
IEC 60958-1, Digital audio interface – Part 1: General
IEC 60958-3, Digital audio interface – Part 3: Consumer applications
IEC 61937-1, Digital audio – Interface for non-linear PCM encoded audio bitstreams applying
IEC 60958 – Part 1: General
IEC 61937-2, Digital audio – Interface for non-linear PCM encoded audio bitstreams applying
IEC 60958 – Part 2: Burst-Info
ISO/IEC 14496-3:2009, Information technology – Coding of audio-visual objects – Part 3:
Audio
ISO/IEC 14496-3:2009/AMD2:2010, ALS simple profile and transport of SAOC
ISO/IEC 14496-3:2009/AMD5:2015, Support for Dynamic Range Control, New Levels for ALS
Simple Profile, and Audio Synchronization
3 Terms, definitions, abbreviated terms and conventions
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/
...