IEC 60461:2010

Time and control code

IEC 60461:2012 specifies a digital time and control code for use in television, film, and accompanying audio systems operating at nominal rate of 60, 59, 94, 50, 30, 29, 97, 25, 24 and 23,98 frames per second. This International Standard specifies a time address, binary groups, and flag bit structure. In addition, the standard specifies a binary group flag assignment, a linear time code transport, and a vertical interval time code transport. It cancels and replaces the third edition published in 2001, of which it constitutes a technical revision. It includes the following significant change with regard to the previous edition: The time code for progressive television systems with a frame rate greater than 30 frames per second is added. This bilingual version (2012-01) corresponds to the monolingual English version, published in 2010-03.

Code temporel et de commande

La IEC 60461 :2010 spécifie un code temporel et de commande numérique destiné aux systèmes de télévision, films et systèmes audio annexes, fonctionnant à des fréquences image nominales de 60, 59,94, 50, 30, 29,97, 25, 24 et 23,98 images par seconde. La présente Norme internationale spécifie une structure d'adresse temporelle, de groupes binaires et de bits drapeaux. Cette norme spécifie en outre une affectation des drapeaux des groupes binaires, un transport linéaire du code temporel et un transport du code temporel dans l'intervalle vertical. Cette quatrième édition annule et remplace la troisième édition parue en 2001, dont elle constitue une révision technique. Par rapport à l'édition précédente elle comporte la modification significative suivante: est ajouté le code temporel pour des systèmes de télévision à balayage progressif de fréquence image supérieure à 30 images par seconde. La présente version bilingue (2012-02) correspond à la version anglaise monolingue publiée en 2010-03.

General Information

• Status: Published
• Publication Date: 29-Mar-2010
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 33.160.40 - Video systems
• ICS: 33.170 - Television and radio broadcasting
• Technical Committee: TC 100 - Audio, video and multimedia systems and equipment
• Current Stage: PPUB - Publication issued
• Start Date: 30-Jun-2010
• Completion Date: 30-Mar-2010

Relations

• Revises: IEC 60461:2001 - Time and control code for video tape recorders
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60461 ®
Edition 4.0 2010-03
INTERNATIONAL
STANDARD
Time and control code
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

IEC Central Office
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About the IEC
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International Standards for all electrical, electronic and related technologies.

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IEC 60461 ®
Edition 4.0 2010-03
INTERNATIONAL
STANDARD
Time and control code
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
X
ICS 33.160.40; 33.170 ISBN 978-2-88910-197-9
– 2 – 60461 © IEC:2010(E)
CONTENTS
FOREWORD.6
INTRODUCTION.8
1 Scope.9
2 Normative references.9
3 Terms, definitions and reserved .9
3.1 Terms and definitions .9
3.2 Reserved.11
4 Time representation in 30 frames per second and 60 frames per second systems .11
4.1 Definitions of real time and NTSC time.11
4.1.1 Definition of real time.11
4.1.2 Definition of NTSC time .11
4.2 Time address of a frame.11
4.2.1 Definition of time address of a frame.11
4.2.2 Non-drop frame – Uncompensated mode .12
4.2.3 Drop frame – NTSC time compensated mode.12
4.3 Colour frame identification in NTSC analogue composite television systems.12
5 Time representation in 25 frames per second and 50 frames per second systems .12
5.1 Definition of real time.12
5.2 Time address of a frame.12
5.3 Colour frame identification in PAL analogue composite television systems .13
5.3.1 Colour frame identification .13
5.3.2 Logical relationship .13
5.3.3 Arithmetic relationship .13
6 Time representation in 24-frame systems.13
6.1 Definitions of real time and NTSC time.13
6.1.1 Definition of real time.13
6.1.2 Definition of NTSC time .14
6.2 Time address of a frame.14
7 Structure of the time address and control bits.14
7.1 Numeric code .14
7.2 Time address .14
7.3 Flag bits .14
7.3.1 Definition of flag bits .14
7.3.2 Drop frame flag (NTSC composite television system only) .14
7.3.3 Colour frame flag (NTSC and PAL composite television systems only).14
7.3.4 Binary group flags.15
7.3.5 Modulation method specific flag .15
7.4 Use of the binary groups.15
7.4.1 Binary group flag assignments .15
7.4.2 Character set not specified and unspecified clock time (BGF2=0,
BGF1=0, BGF0=0) .15
7.4.3 Eight-bit character set and unspecified clock time (BGF2=0, BGF1=0,
BGF0=1).15
7.4.4 Date/time zone and unspecified clock time (BGF2=1, BGF1=0,
BGF0=0).16
7.4.5 Page/line multiplex system and unspecified clock time (BGF2=1,
BGF1=0, BGF0=1) .16

60461 © IEC:2010(E) – 3 –
7.4.6 Clock time specified and unspecified character set (BGF2=0, BGF1=1,
BGF0=0).16
7.4.7 Unassigned binary group usage and unassigned clock time (BGF2=0,
BGF1=1, BGF0=1) .16
7.4.8 Date/time zone and clock time (BGF2=1, BGF1=1, BGF0=0) .16
7.4.9 Specified clock time and page/line multiplex system (BGF2=1,
BGF1=1, BGF0=1) .16
7.5 Clock time reference – Binary group flag combinations.16
8 Linear time code application.17
8.1 Code word format .17
8.2 Code word data content .17
8.2.1 LTC code word content .17
8.2.2 Time address.17
8.2.3 Flag bits .17
8.2.4 Binary groups .18
8.2.5 Synchronization word .18
8.2.6 Biphase mark polarity correction .19
8.3 Modulation method .19
8.4 Bit rate .20
8.5 Timing of the code word relative to a television signal .20
8.6 Linear time code interface electrical and mechanical characteristics.21
8.6.1 Measurements .21
8.6.2 Rise/fall time.21
8.6.3 Amplitude distortion .21
8.6.4 Timing of the transitions.21
8.6.5 Interface connector .21
8.6.6 Output impedance.21
8.6.7 Output amplitude .21
9 Vertical interval application – Analogue television systems .26
9.1 Code word format .26
9.2 Code word data content .26
9.2.1 VITC code word content.26
9.2.2 Time address.29
9.2.3 Flag bits .29
9.2.4 Binary groups .29
9.2.5 Field mark flag.30
9.2.6 Synchronization bits.30
9.2.7 Cyclic redundance check code .30
9.3 Modulation method .31
9.4 Bit timing .31
9.5 Timing of the code word relative to the television signal .32
9.5.1 525/59,94 television system .32
9.5.2 625/50 television system .32
9.6 Location of the address code signal in the vertical interval .32
9.6.1 Location of the VITC code.32
9.6.2 525/59,94 television system .32
9.6.3 625/50 television system .32
9.6.4 Component television system.32
9.7 Redundancy .32

– 4 – 60461 © IEC:2010(E)
9.8 Vertical interval time code waveform characteristics.33
9.8.1 Waveform characteristics.33
9.8.2 Logic level .33
9.8.3 Rise/fall time.33
9.8.4 Amplitude distortion .33
10 Relationship between LTC and VITC .33
10.1 Time address data.33
10.2 Binary group data .33
10.2.1 General .33
10.2.2 Transferring vertical interval binary group data to linear binary group
data.34
10.2.3 Transferring linear binary group data to vertical interval binary group
data.34
10.3 VITC and LTC
...

IEC 60461 ®
Edition 4.0 2010-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Time and control code
Code temporel et de commande
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

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International Standards for all electrical, electronic and related technologies.

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IEC 60461 ®
Edition 4.0 2010-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Time and control code
Code temporel et de commande
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX X
ICS 33.160.40; 33.170 ISBN 978-2-88912-849-5

– 2 – 60461  IEC:2010
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references. 9
3 Terms, definitions and reserved . 9
3.1 Terms and definitions . 9
3.2 Reserved . 11
4 Time representation in 30 frames per second and 60 frames per second systems . 11
4.1 Definitions of real time and NTSC time . 11
4.1.1 Definition of real time . 11
4.1.2 Definition of NTSC time . 11
4.2 Time address of a frame . 11
4.2.1 Definition of time address of a frame . 11
4.2.2 Non-drop frame – Uncompensated mode . 12
4.2.3 Drop frame – NTSC time compensated mode . 12
4.3 Colour frame identification in NTSC analogue composite television systems . 12
5 Time representation in 25 frames per second and 50 frames per second systems . 12
5.1 Definition of real time . 12
5.2 Time address of a frame . 12
5.3 Colour frame identification in PAL analogue composite television systems . 13
5.3.1 Colour frame identification . 13
5.3.2 Logical relationship . 13
5.3.3 Arithmetic relationship . 13
6 Time representation in 24-frame systems . 13
6.1 Definitions of real time and NTSC time . 13
6.1.1 Definition of real time . 13
6.1.2 Definition of NTSC time . 14
6.2 Time address of a frame . 14
7 Structure of the time address and control bits . 14
7.1 Numeric code . 14
7.2 Time address . 14
7.3 Flag bits . 14
7.3.1 Definition of flag bits . 14
7.3.2 Drop frame flag (NTSC composite television system only) . 14
7.3.3 Colour frame flag (NTSC and PAL composite television systems only) . 14
7.3.4 Binary group flags . 15
7.3.5 Modulation method specific flag . 15
7.4 Use of the binary groups . 15
7.4.1 Binary group flag assignments . 15
7.4.2 Character set not specified and unspecified clock time (BGF2=0,
BGF1=0, BGF0=0) . 15
7.4.3 Eight-bit character set and unspecified clock time (BGF2=0, BGF1=0,
BGF0=1) . 15
7.4.4 Date/time zone and unspecified clock time (BGF2=1, BGF1=0,
BGF0=0) . 16
7.4.5 Page/line multiplex system and unspecified clock time (BGF2=1,
BGF1=0, BGF0=1) . 16

60461  IEC:2010 – 3 –
7.4.6 Clock time specified and unspecified character set (BGF2=0, BGF1=1,
BGF0=0) . 16
7.4.7 Unassigned binary group usage and unassigned clock time (BGF2=0,
BGF1=1, BGF0=1) . 16
7.4.8 Date/time zone and clock time (BGF2=1, BGF1=1, BGF0=0) . 16
7.4.9 Specified clock time and page/line multiplex system (BGF2=1,
BGF1=1, BGF0=1) . 16
7.5 Clock time reference – Binary group flag combinations. 16
8 Linear time code application. 17
8.1 Code word format . 17
8.2 Code word data content . 17
8.2.1 LTC code word content . 17
8.2.2 Time address . 17
8.2.3 Flag bits . 17
8.2.4 Binary groups . 18
8.2.5 Synchronization word . 18
8.2.6 Biphase mark polarity correction . 19
8.3 Modulation method . 19
8.4 Bit rate . 20
8.5 Timing of the code word relative to a television signal . 20
8.6 Linear time code interface electrical and mechanical characteristics . 21
8.6.1 Measurements . 21
8.6.2 Rise/fall time . 21
8.6.3 Amplitude distortion . 21
8.6.4 Timing of the transitions . 21
8.6.5 Interface connector . 21
8.6.6 Output impedance . 21
8.6.7 Output amplitude . 21
9 Vertical interval application – Analogue television systems . 26
9.1 Code word format . 26
9.2 Code word data content . 26
9.2.1 VITC code word content . 26
9.2.2 Time address . 29
9.2.3 Flag bits . 29
9.2.4 Binary groups . 29
9.2.5 Field mark flag . 30
9.2.6 Synchronization bits . 30
9.2.7 Cyclic redundance check code . 30
9.3 Modulation method .
...