IEC 61937-12:2010

IEC 61937-12 ®
Edition 1.0 2010-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Digital audio – Interface for non-linear PCM encoded audio bitstreams applying
IEC 60958 –
Part 12: Non-linear PCM bitstreams according to the DRA formats

Audionumérique – Interface pour les flux de bits audio à codage MIC non
linéaire conformément à la CEI 60958 –
Partie 12: Flux de bits MIC non linéaire selon les formats DRA

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IEC 61937-12 ®
Edition 1.0 2010-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Digital audio – Interface for non-linear PCM encoded audio bitstreams applying
IEC 60958 –
Part 12: Non-linear PCM bitstreams according to the DRA formats

Audionumérique – Interface pour les flux de bits audio à codage MIC non
linéaire conformément à la CEI 60958 –
Partie 12: Flux de bits MIC non linéaire selon les formats DRA

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
N
CODE PRIX
ICS 33.160.30; 33.170 ISBN 978-2-88912-146-5
– 2 – 61937-12 © IEC:2010
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 – 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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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.
This bilingual version, published in 2010-10, corresponds to the English version.
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.

– 4 – 61937-12 © IEC:2010
The French version of this standard has not been voted upon.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
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.
61937-12 © IEC:2010 – 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
...