IEC TS 62312-2:2018

IEC TS 62312-2 ®
Edition 2.0 2018-11
TECHNICAL
SPECIFICATION
Guideline for synchronization of audio and video –
Part 2: Methods for synchronization of audio and video systems

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IEC TS 62312-2 ®
Edition 2.0 2018-11
TECHNICAL
SPECIFICATION
Guideline for synchronization of audio and video –

Part 2: Methods for synchronization of audio and video systems

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.160.01 ISBN 978-2-8322-6188-0

– 2 – IEC TS 62312-2:2018 © IEC 2018
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 System model . 7
4.1 Audio and video system . 7
4.2 System model . 7
4.3 Audio and video device . 7
4.4 Controller . 9
4.5 Source device and display device . 9
4.6 Controller function of audio and video device . 10
5 Methods for synchronization . 11
5.1 Information for synchronization . 11
5.1.1 Time-code information . 11
5.1.2 Latency information . 11
5.1.3 Synchronization information . 11
5.2 Methods for synchronization . 12
5.2.1 General . 12
5.2.2 Method with time-code information . 13
5.2.3 Method with latency information . 14
5.2.4 Method with synchronization information . 14
5.3 Method with IEC 60958-3 . 14
5.4 Method with IEC 61883-6 . 14
5.5 Method with other interface specifications . 15
Annex A (informative) Information for synchronization . 16
A.1 Time-code information . 16
A.2 Latency information . 16
A.3 Synchronization information . 16
Bibliography . 17

Figure 1 – System model . 7
Figure 2 – Audio and video device . 8
Figure 3 – Information and control in audio and video device . 9
Figure 4 – Source device . 10
Figure 5 – Display device . 10
Figure 6 – Audio amplifier . 10
Figure 7 – Controller function of audio and video device . 11
Figure 8 – Additional delay . 12
Figure 9 – Multiple reproductions . 13

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDELINE FOR SYNCHRONIZATION OF AUDIO AND VIDEO –

Part 2: Methods for synchronization of audio and video systems

FOREWORD
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The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a Technical
Specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical Specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC 62312-2, which is a technical specification, has been prepared by technical area 11:
Quality for audio, video and multimedia systems, of IEC technical committee 100: Audio,
video and multimedia systems and equipment.

– 4 – IEC TS 62312-2:2018 © IEC 2018
This second edition cancels and replaces the first edition published in 2007. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) fingerprint is newly introduced;
b) addition of the synchronization information from fingerprint (SMPTE spec.);
c) addition of the method for using the above information.
The text of this Technical Specification is based on the following documents:
Draft TS Report on voting
100/3049/DTS 100/3106/RVDTS
Full information on the voting for the approval of this Technical Specification 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.
The list of all the parts of IEC 62312, published under the general title Guideline for
synchronization of audio and video, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

INTRODUCTION
Audio, video and multimedia systems and equipment have begun to use digital technologies.
Digital systems or equipment may cause delay of audio and video signals because digital
signal processing causes latency and delay. The unevenness of the delay between audio and
video can cause synchronization problems.
For instance, a digital broadcasting system uses signal compression of audio and video. A
receiver has signal decoders, and this can cause unevenness of the delay between audio and
...