SIST EN 61937-12:2010

Digital audio - Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 - Part 12: Non-linear PCM bitstreams according to the DRA formats (IEC 61937-12:2010)

IEC 61937-12:2010(E) specifies the method for IEC 60958 to convey non-linear PCM bitstreams encoded in accordance with the DRA formats.

Digitalton - Schnittstelle für nichtlinear-PCM-codierte Audio-Bitströme unter Verwendung von IEC 60958 - Teil 12: Nichtlineare PCM-Bitströme entsprechend DRA-Formaten (IEC 61937-12:2010)

Audionumérique - Interface pour les flux de bits audio à codage MIC non linéaire conformément à la CEI 60958 - Partie 12 : Flux de bits à codage MIC non linéaire conforme au format DRA (CEI 61937-12:2010)

La CEI 61937-12:2010 spécifie la méthode de la CEI 60958 pour acheminer des flux de bits MIC non linéaires codés selon les formats DRA. La présente version bilingue, publiée en 2010-10, correspond à la version anglaise. La version française de cette norme n'a pas été soumise au vote.

Digitalni avdio - Vmesnik za nelinearne PCM kodirane avdio bitne struje po IEC 60958 - 12. del: Bitne struje nelinearne PCM v formatih DRA (IEC 61937-12:2010)

Ta del IEC 61937 določa metodo za IEC 60958 za prenos nelinearne PCM bitne struje, kodirane v skladu z DRA formati.

General Information

• Status: Published
• Publication Date: 13-Oct-2010
• ICS: 33.160.30 - Audio systems
• ICS: 35.200 - Interface and interconnection equipment
• Technical Committee: AVM - Audio, video and multimedia systems and equipment
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 04-Oct-2010
• Due Date: 09-Dec-2010
• Completion Date: 14-Oct-2010
• Ref Project: EN 61937-12:2010 - Digital audio - Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 - Part 12: Non-linear PCM bitstreams according to the DRA formats

Overview

EN 61937-12:2010 (equivalent to IEC 61937-12:2010) defines how to carry non‑linear PCM audio bitstreams encoded in the DRA formats over the digital audio interface specified by IEC 60958. In practical terms, this part of the EN/IEC 61937 family describes the packet (data‑burst) structure, timing, and signalling needed so DRA‑encoded streams can be transmitted, detected and decoded across consumer and professional digital audio links.

Keywords: EN 61937-12:2010, IEC 61937-12, DRA formats, IEC 60958, digital audio interface, non-linear PCM, burst-info, data-burst.

Key topics and technical requirements

• Scope: Specifies the method for IEC 60958 to convey DRA (Digital Rise Audio) non‑linear PCM bitstreams.
• Burst-info and data-type: Defines a 16‑bit burst‑info (Pc) field and assigns the DRA data‑type/sub‑data‑type (data‑type = 23, sub‑data‑type = 3).
• Data‑burst format: Each DRA audio data‑burst comprises a burst‑preamble, a burst‑payload containing one complete DRA frame, and stuffing bits to fill IEC 60958 frames.
• Frame size and samples: A DRA data‑burst payload represents 1 024 samples per encoded channel; length-code (Pd) units are in bytes.
• Sampling‑rate relation: Bits 8–9 of Pc identify the relation between DRA sampling frequency and the IEC 60958 frame rate:
  • 00 = regular rate (repetition period 1 024 IEC 60958 frames)
  • 01 = half‑rate low sampling frequency (2 048 frames)
  • 10 = quarter‑rate low sampling frequency (4 096 frames)
  • 11 = reserved
• Pause data‑bursts: Recommended repetition periods for pause bursts are 32, 64 or 128 IEC 60958 frames depending on the sampling‑rate relation.
• Latency signalling: The standard defines the notion of decoding latency (sum of receive and decode delays) and requires transmitters to schedule bursts considering latency to maintain AV sync.
• Normative references: The document references IEC 60958, IEC 61937 (parts 1 & 2) and points to the DRA frame specification (e.g., GB/T 22726‑2008).

Practical applications

• Interoperability of DRA‑encoded audio over S/PDIF or AES3 links that follow IEC 60958 framing
• Implementation guidance for audio interface firmware, digital audio transmitters, and decoder front‑ends
• Design of consumer electronics (set‑top boxes, DVD/Blu‑ray players), broadcast encoders and professional audio equipment that need to carry DRA streams
• Test labs and conformance testing for digital audio transport and synchronization

Who should use this standard

• Audio equipment manufacturers and hardware engineers
• Codec and DSP developers implementing DRA encoders/decoders
• System integrators and firmware developers for digital audio interfaces
• Test laboratories and standards compliance teams

Related standards

• IEC 60958 (Digital audio interface)
• IEC 61937-1 (General) and IEC 61937-2 (Burst‑info)
• DRA format specification (e.g., GB/T 22726‑2008)

This standard is essential when transporting DRA non‑linear PCM over IEC 60958 interfaces to ensure correct framing, timing, latency handling and interoperability.

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2010
Digitalni avdio - Vmesnik za nelinearne PCM kodirane avdio bitne struje po IEC
60958 - 12. del: Bitne struje nelinearne PCM v formatih DRA (IEC 61937-12:2010)
Digital audio - Interface for non-linear PCM encoded audio bitstreams applying IEC
60958 - Part 12: Non-linear PCM bitstreams according to the DRA formats (IEC 61937-
12:2010)
Digitalton - Schnittstelle für nichtlinear-PCM-codierte Audio-Bitströme unter Verwendung
von IEC 60958 - Teil 12: Nichtlineare PCM-Bitströme entsprechend DRA-Formaten (IEC
61937-12:2010)
Audionumérique - Interface pour les flux de bits audio à codage MIC non linéaire
conformément à la CEI 60958 - Partie 12 : Flux de bits à codage MIC non linéaire
conforme au format DRA (CEI 61937-12:2010)
Ta slovenski standard je istoveten z: EN 61937-12:2010
ICS:
33.160.30 Avdio sistemi Audio systems
35.200 Vmesniška in povezovalna Interface and interconnection
oprema equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 61937-12
NORME EUROPÉENNE
June 2010
EUROPÄISCHE NORM
ICS 33.160.30; 33.170
English version
Digital audio -
Interface for non-linear PCM encoded audio bitstreams
applying IEC 60958 -
Part 12: Non-linear PCM bitstreams according to the DRA formats
(IEC 61937-12:2010)
Audionumérique -  Digitalton – Schnittstelle für nichtlinear-
Interface pour les flux de bits audio PCM-codierte Audio-Bitströme
à codage MIC non linéaire unter Verwendung von IEC 60958 –
conformément à la CEI 60958 - Teil 12: Nichtlineare PCM-Bitströme
Partie 12 : Flux de bits à codage MIC entsprechend DRA-Formaten
non linéaire conforme au format DRA (IEC 61937-12:2010)
(CEI 61937-12:2010)
This European Standard was approved by CENELEC on 2010-06-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2010 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61937-12:2010 E
Foreword
The text of document 100/1578/CDV, future edition 1 of IEC 61937-12, prepared by IEC TC 100, Audio,
video and multimedia systems and equipment, was submitted to the IEC-CENELEC parallel vote and was
approved by CENELEC as EN 61937-12 on 2010-06-01.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
(dop) 2011-03-01
national standard or by endorsement
– latest date by which the national standards conflicting
(dow) 2013-06-01
with the EN have to be withdrawn
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61937-12:2010 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60958-1 NOTE  Harmonized as EN 60958-1.
IEC 60958-3 NOTE  Harmonized as EN 60958-3.
__________
- 3 - EN 61937-12:2010
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

IEC 60958 Series Digital audio interface EN 60958 Series

IEC 61937 Series Digital audio - Interface for non-linear PCM EN 61937 Series
encoded audio bitstreams
applying IEC 60958
IEC 61937-1 2007 Digital audio - Interface for non-linear PCM EN 61937-1 2007
encoded audio bitstreams
applying IEC 60958 -
Part 1: General
IEC 61937-2 - Digital audio - Interface for non-linear PCM EN 61937-2 -
encoded audio bitstreams
applying IEC 60958 -
Part 2: Burst-info
IEC 61937-12 ®
Edition 1.0 2010-05
INTERNATIONAL
STANDARD
Digital audio – Interface for non-linear PCM encoded audio bitstreams applying
IEC 60958 –
Part 12: Non-linear PCM bitstreams according to the DRA formats

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
N
ICS 33.160.30; 33.170 ISBN 978-2-88910-934-0
– 2 – 61937-12 © IEC:2010(E)
CONTENTS
FOREWORD.3
1 Scope.5
2 Normative references .5
3 Terms and definitions .5
3.1 Terms and definitions .5
3.2 Abbreviations .6
3.3 Presentation convention .6
4 DRA burst-info.6
5 Format of DRA data-bursts .6
5.1 General .6
5.2 Pause data-burst.7
5.3 Audio data-bursts .7
5.3.1 DRA condition .7
5.3.2 DRA half-rate low sampling frequency condition .9
5.3.3 DRA quarter-rate low sampling frequency condition.11
Bibliography.14

Figure 1 – DRA data-burst .8
Figure 2 – Latency of DRA decoding.9
Figure 3 – DRA data-burst half-rate low sampling frequency.10
Figure 4 – Latency of DRA decoding half-rate low sampling frequency .11
Figure 5 – DRA data-burst quarter-rate low sampling frequency.12
Figure 6 – Latency of DRA decoding quarter-rate low sampling frequency .13

Table 1 – Fields of burst-info .6
Table 2 – Data-type-dependent information for data-type DRA.7
Table 3 – Repetition period of pause data-bursts .7

61937-12 © IEC:2010(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIGITAL AUDIO –
INTERFACE FOR NON-LINEAR PCM ENCODED
AUDIO BITSTREAMS APPLYING IEC 60958 –

Part 12: Non-linear PCM bitstreams according to the DRA formats

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61937-12 has been prepared by technical area 4: Digital system
interfaces and protocols, of IEC technical committee 100: Audio, video and multimedia
systems and equipment.
The text of this standard is based on the following documents:
CDV Report on voting
100/1578/CDV 100/1651/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – 61937-12 © IEC:2010(E)
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

61937-12 © IEC:2010(E) – 5 –
DIGITAL AUDIO –
INTERFACE FOR NON-LINEAR PCM ENCODED
AUDIO BITSTREAMS APPLYING IEC 60958 –

Part 12: Non-linear PCM bitstreams according to the DRA formats

1 Scope
This part of IEC 61937 specifies the method for IEC 60958 to convey non-linear PCM
bitstreams encoded in accordance with the DRA formats.
2 Normative references
The following referenced documents are indispensable for the application 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 (all parts), Digital audio interface
IEC 61937 (all parts), Digital audio – Interface for non-linear PCM encoded audio bitstreams
applying IEC 60958
IEC 61937-1:2007, 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
3 Terms and definitions
For the purposes of this document, the following terms, definitions, abbreviations and
presentation conventions apply.
3.1 Terms and definitions
3.1.1
sub data-type
type of payload of the data-burst for use with the specified data-type
3.1.2
latency
delay time of an external audio decoder to decode a DRA data-burst
NOTE It is defined as the sum of two values of the receiving delay time and the decoding delay time.
3.1.3
length code
indicates the length of t
...