IEC 61966-12-2:2024

IEC 61966-12-2 ®
Edition 2.0 2024-10
INTERNATIONAL
STANDARD
Multimedia systems and equipment – Colour measurement and management –
Part 12-2: Simple metadata format for identification of colour gamut

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IEC 61966-12-2 ®
Edition 2.0 2024-10
INTERNATIONAL
STANDARD
Multimedia systems and equipment – Colour measurement and management –

Part 12-2: Simple metadata format for identification of colour gamut

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 17.180.20; 33.160.40 ISBN 978-2-8322-9821-3

– 2 – IEC 61966-12-2:2024 © IEC 2024
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Simple description of gamut . 7
5 Relationship with IEC 61966-12-1 . 9
Annex A (informative) Conversion from IEC 61966-12-2 to IEC 61966-12-1 simple
profile . 11
Annex B (informative) Example of simple metadata format and conversion to
IEC 61966-12-1 simple profile . 13
Annex C (informative) Handling HDR content . 18
C.1 General . 18
C.2 Relationship with other HDR related standards . 18
Bibliography . 20

Figure 1 – The colour gamut for display types comprising three primary additive
colours . 9
Figure 2 – IEC 61966-12-1 full and medium profiles . 10
Figure 3 – IEC 61966-12-1 simple profile and IEC 61966-12-2 . 10

Table 1 – Simple metadata format for identification of colour gamut . 8
Table 2 – Differences of IEC 61966-12-1 simple profile and IEC 61966-12-2 . 10
Table B.1 – Colour gamut for IEC 61966-2-5 opRGB . 13
Table B.2 – Encoded simple metadata format . 14
Table B.3 – Conversion result to CIE-XYZ values for five colour vertices . 14
Table B.4 – Example for the header . 15
Table B.5 – Example for the header of description of gamut geometry . 15
Table B.6 – Example of definition of vertices. 15
Table B.7 – Example of encoded colour space coordinates for vertices. 16
Table C.1 – P3D65x1000n0005 in ITU-R H Supl.19 . 18
Table C.2 – Metadata example when distributing content whose colour gamut is DCI-P3 . 19

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MULTIMEDIA SYSTEMS AND EQUIPMENT –
COLOUR MEASUREMENT AND MANAGEMENT –

Part 12-2: Simple metadata format for identification of colour gamut

FOREWORD
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IEC 61966-12-2 has been prepared by technical area 2: Colour measurement and management,
of IEC technical committee 100: Audio, video and multimedia systems and equipment. It is an
International Standard.
This second edition cancels and replaces the first edition published in 2014. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the number of bits of metadata format has been extended in Clause 4;
b) Annex C has been added for handling HDR content.

– 4 – IEC 61966-12-2:2024 © IEC 2024
The text of this International Standard is based on the following documents:
Draft Report on voting
100/3847/CDV 100/4109/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts of the IEC 61966 series, published under the general title Multimedia systems
and equipment – Colour measurement and management, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
INTRODUCTION
New technologies in capturing and displaying wide-gamut colour images enable a new market
of wide-gamut video colour content creation. Recent video standards for wide gamut colour
space encoding such as ITU-R BT.2100 (HDR), ITU-R BT.2020 (UHDTV) and IEC 61966-2-4
(xvYCC) were developed in order to be able to distribute content with a colour gamut that is
extended with respect to classical colour gamuts such as those defined by standards ITU-R
BT.601 (standard-definition television) and ITU-R BT.709 (high-definition television). With the
increasing popularity of wide gamut and high dynamic range content and displays, the variety
of colour gamuts of displays is expected to increase. This issue can be an obstacle to adoption
of wide-gamut video colour content in professional content creation since the compatibility of
the content to the employed displays, as well as the compatibility among different displays, is
not ensured. The term "display" includes here any video colour reproduction equipment, such
as direct view displays and projectors. Thanks to improvements in technology, the variety of
colour gamuts and colour reproduction capacities of displays are increasing while the colour
gamut and the colour encoding rules of existing colour space encoding standards are fixed.
To address this issue, IEC 61966-12-1 (Metadata for identification of colour gamut (Gamut ID))
specifies a colour gamut metadata scheme for video systems including information for colour
reproduction. This metadata can apply to video content or displays. More specifically,
improvements can be achieved if the wide-gamut colour content is created with the knowledge
of the display colour gamut and if the colour reproduction in the display is done with the
knowledge of the colour gamut of the pictorial content.
IEC 61966-12-1 has the capability to describe arbitrary 3D colour gamuts in a given colour
space and include the full/medium profile for professional use and the simple profile for
consumer use with easier product implementation. This approach is effective, but some
ambiguities can occur in practical
...