IEC 61937-3:2003

INTERNATIONAL IEC
STANDARD
61937-3
First edition
2003-05
Digital audio –
Interface for non-linear PCM encoded
audio bitstreams applying IEC 60958 –
Part 3:
Non-linear PCM bitstreams
according to the AC-3 format
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INTERNATIONAL IEC
STANDARD
61937-3
First edition
2003-05
Digital audio –
Interface for non-linear PCM encoded
audio bitstreams applying IEC 60958 –
Part 3:
Non-linear PCM bitstreams
according to the AC-3 format
 IEC 2003  Copyright - all rights reserved
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–  – 61937-3  IEC:2003(E)
CONTENTS
FOREWORD . 3

1 Scope . 5

2 Normative references. 5

3 Terms and definitions . 5

3.1 Definitions . 5

3.2 Abbreviations. 5
3.3 Presentation convention . 6
4 Mapping of the audio bitstream on to IEC 61937. 6
4.1 AC-3 burst-info . 6
5 Format of AC-3 data-burst . 6
5.1 General . 6
5.2 Pause data-burst . 6
5.3 Audio data-bursts . 6
5.3.1 The data AC-3 . 6
5.3.2 Latency of AC-3 decoding . 7
Bibliography. 9
Figure 1 – AC-3 data-burst, with reference point R. 7
Figure 2 – Latency of AC-3 decoding . 8
Table 1 – Fields of burst-info.6
Table 2 – Repetition period of pause data-bursts . 6
Table 3 – Data-type-dependent when data-type = 1 . 7

61937-3  IEC:2003(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
DIGITAL AUDIO –
INTERFACE FOR NON-LINEAR PCM ENCODED

AUDIO BITSTREAMS APPLYING IEC 60958 –

Part 3: Non-linear PCM bitstreams according to the AC-3 format

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes International Standards. Their preparation is
entrusted to technical committees; any IEC National Committee interested in the subject dealt with may
participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. The IEC collaborates closely with the International
Organization for Standardization (ISO) in accordance with conditions determined by agreement between the
two organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61937-3 has been prepared by technical area 4: Digital system
interfaces, of IEC technical committee 100: Audio, video and multimedia systems and
equipment.
This standard cancels and replaces IEC 61937, published in 2000, which has been divided
into four parts (see below). This first edition constitutes a technical revision.

The text of this standard is based on the following documents:
FDIS Report on voting
100/646/FDIS 100/672/RVD
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.

–  – 61937-3  IEC:2003(E)
IEC 61937 consists of the following parts under the general title Digital audio – Interface for
non-linear PCM encoded audio bistreams applying IEC 60958:

Part 1: General
Part 2: Burst-info
Part 3: Non-linear PCM bitstreams according to the AC-3 format

Part 4: Non-linear PCM bitstreams according to the MPEG audio formats

Part 5: Non-linear PCM bitstreams according to the DTS (Digital Theatre Systems) format(s)

Part 6: Non-linear PCM bitstreams according to the MPEG-2 AAC format

Part 7: Non-l
...