ISO 18620:2016

Graphic technology — Prepress data exchange — Tone adjustment curves exchange

ISO 18620:2016 specifies a simple extensible format for the exchange of tone adjustment curves between applications including but not limited to colour management, calibration and raster image processor systems.

Technologie graphique — Échange de données pré-imprimées — Échanges des courbes d'ajustement des tons

General Information

• Status: Published
• Publication Date: 26-Apr-2016
• ICS: 37.100.01 - Graphic technology in general
• Technical Committee: ISO/TC 130 - Graphic technology
• Drafting Committee: ISO/TC 130/WG 2 - Prepress data exchange
• Parallel Committee: ISO/TC 6/SC 2 - Test methods and quality specifications for paper and board
• Current Stage: 9093 - International Standard confirmed
• Completion Date: 07-Sep-2021

Relations

• Consolidated By: ISO 8044:2020 - Corrosion of metals and alloys — Vocabulary
• Effective Date: 06-Jun-2022

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 18620
First edition
2016-05-01
Graphic technology — Prepress data
exchange — Tone adjustment curves
exchange
Technologie graphique — Échange de données pré-imprimées —
Échanges des courbes d’ajustement des tons
Reference number
ISO 18620:2016(E)
©
ISO 2016

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ISO 18620:2016(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2016 – All rights reserved

---------------------- Page: 2 ----------------------
ISO 18620:2016(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 1
4.1 Text styles . 1
4.2 Data types . 1
5 Requirements . 2
5.1 XML Namespace . 2
5.2 File structure . 2
5.2.1 General. 2
5.2.2 TransferCurveSet . 2
5.2.3 FormPreparationDetails . 3
5.2.4 PrintingCondition . 3
5.2.5 TransferCurve . 4
5.3 Interpretation of TransferCurve . 5
5.4 Examples . 5
5.4.1 Example 1 . 5
5.4.2 Example 2 . 6
Annex A (informative) Schema . 8
Bibliography .10
© ISO 2016 – All rights reserved iii

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ISO 18620:2016(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 130, Graphic technology.
iv © ISO 2016 – All rights reserved

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ISO 18620:2016(E)

Introduction
The aim of this International Standard is to define a simple format to exchange data of Tone Adjustment
Curves (also called transfer functions and plate curves) between applications including, but not limited
to, colour management, calibration and raster image processor systems.
In many cases, it is useful to be able to provide calibration data for printing plates in a standard form
to ensure easy and accurate exchange of data. Graphic arts raster image processor vendors all provide
support for printing plate calibration and adjustment of tone curves for digital presses using essentially
the same data, however, each uses a proprietary format. One consequence of this is that companies
providing tools to support print certification need to provide support for many different file formats.
Increasingly, the importance of calibration is being recognized by printers who wish to provide a single,
often centralized, solution for calibration and in this context it is becoming increasingly difficult to
keep up with the many different formats in use.
TC 130 experts know of no commercial reason for each vendor to adopt a different standard and believe
that if there was an ISO standard format, this would be likely to be adopted by the industry. This
International Standard aims to define the minimum set of data required by all of today’s applications
and provide a format that is easily extensible so that additional metadata can be included when agreed
on between the parties.
© ISO 2016 – All rights reserved v

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INTERNATIONAL STANDARD ISO 18620:2016(E)
Graphic technology — Prepress data exchange — Tone
adjustment curves exchange
1 Scope
This International Standard specifies a simple extensible format for the exchange of tone adjustment
curves between applications including but not limited to colour management, calibration and raster
image processor systems.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
Namespaces in XML 1.0 (Third Edition), W3C (World Wide Web Consortium) Recommendation 8
1)
December 2009
XML Schema Part 2: Datatypes (Second Edition), W3C (World Wide Web Consortium) Recommendation
2)
28 October 2004
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
transfer curve
curve that defines the relationship between input code values and output values, imaged or printed
4 Symbols and abbreviated terms
4.1 Text styles
The following documentation conventions are used.
Names of XML elements are shown in bold type, for example TransferCurve.
Names of XML attributes are shown in italics, for example SpotColorName.
4.2 Data types
All datatypes used in this International Standard are as defined by XML Schema Part 2: Datatypes.
st
1) Available at http://www.w3.org/TR/REC-xml-names/. [Accessed 21 December 2015].
st
2) Available at http://www.w3.org/TR/2004/REC-xmlschema-2-20041028/. [Accessed 21 December 2015].
© ISO 2016 – All rights reserved 1

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ISO 18620:2016(E)

5 Requirements
5.1 XML Namespace
This International Standard relies on XML to ensure clear communication of metadata. It is very likely
that different systems will want to add elements and attributes whose intended use falls outside of this
specification.
Extension of this sort is well supported by XML and the following rules apply.
— All elements and attributes defined by this International Standard shall use the namespace ‘http://
www.npes.org/schema/ISO18620/’.
— Vendor-specific attributes and elements may be included and when included shall be defined in a
vendor-specific namespace as described in “Namespaces in XML 1.0”.
— Compliant reader applications may safely ignore vendor specific attributes and elements. These
attributes and elements may enable additional functionality in closed environments but shall not
change the base functionality as defined in elements and attributes defined in this International
Standard.
Such proprietary elements and attributes are out of the scope of this International Standard.
5.2 File structure
5.2.1 General
The file is intended to contain a single set of transfer curves comprising one or more transfer curves. A
schema is provided in Annex A for information.
The first line of the file shall be as follows:

5.2.2 TransferCurveSet
A single TransferCurveSet element shall be included and shall be as shown in Table 1.
Table 1 — TransferCurveSet element
a
Name Cardinality Data type Description
xmlns Required anyURI The namespace shall be declared in accord-
ance with Namespaces in XML1.0 (Third Edition),
Clause 3 and shall be ‘http://www.npes.org/sche-
ma/ISO18620/’.
Creator Optional string Describes the creator of the document. This is usually
the name and version of the authoring application used.
CreationDate Optional dateTime The date and time when the file was created.
OperatorName Optional string Describes the operator who created the file.
PressName Optional string The name used to describe the press for which the
data has been created.
MediaName Optional string The name used to describe the media for which the
data has been created
a
Cardinality: unless otherwise specified, only a single instance of each element or attribute may be included.
2 © ISO 2016 – All rights reserve
...

DRAFT INTERNATIONAL STANDARD
ISO/DIS 18620
ISO/TC 130 Secretariat: SAC
Voting begins on: Voting terminates on:
2015-09-14 2015-12-14
Graphic technology — Prepress data exchange — Tone
adjustment curves exchange
Titre manque
ICS: 37.100.01
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 18620:2015(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
©
PROVIDE SUPPORTING DOCUMENTATION. ISO 2015

---------------------- Page: 1 ----------------------
ISO/DIS 18620:2015(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2015 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/DIS 18620
Contents Page
Foreword . iv
Introduction . v
1  Scope . 1
2  Normative references . 1
3  Terms and definitions . 1
4  Symbols and abbreviated terms . 1
4.1  Text styles . 1
4.2  Data types . 2
5  Requirements . 2
5.1  XML Namespace . 2
5.2  File structure . 2
5.3  Interpretation of TransferCurve . 5
5.4  Examples . 5
Annex A (Informative) Schema . 8
Bibliography . 10

© ISO 2015 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO/DIS 18620
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 18620 was prepared by Technical Committee ISO/TC 130, Graphic technology.
iv © ISO 2015 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/DIS 18620
Introduction
The aim of this standard is to define a simple format to exchange data of Tone Adjustment Curves (also called
transfer functions and plate curves) between applications including but not limited to colour management,
calibration and raster image processor systems.
In many cases it is useful to be able to provide calibration data for printing plates in a standard form to ensure
easy and accurate exchange of data. Graphic arts raster image processor vendors all provide support for
printing plate calibration and adjustment of tone curves for digital presses using essentially the same data,
however each uses a proprietary format. One consequence of this is that companies providing tools to support
print certification must provide support for many different file formats. Increasingly the importance of
calibration is being recognised by printers who wish to provide a single, often centralised, solution for
calibration and in this context it is becoming increasingly difficult to keep up with the many different formats in
use.
TC130 experts know of no commercial reason for each vendor to adopt a different standard and believe that if
there was an ISO standard format this would be likely to be adopted by the industry. This standard aims to
define the minimum set of data required by all of today's applications and provide a format that is easily
extensible so that additional metadata can be included when agreed on between the parties.
© ISO 2015 – All rights reserved v

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DRAFT INTERNATIONAL STANDARD ISO/DIS 18620

Graphic technology — Prepress data exchange — Tone
adjustment curves exchange
1 Scope
This International Standard specifies a simple extensible format for the exchange of tone adjustment curves
between applications including but not limited to colour management, calibration and raster image processor
systems.
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.
Namespaces in XML 1.0 (Third Edition), W3C Recommendation 8 December 2009, available from
http://www.w3.org/TR/REC-xml-names/.
XML Schema Part 2: Datatypes Second Edition, W3C Recommendation 28 October 2004, Produced by:
World Wide Web Consortium (W3C), Available at http://www.w3.org/TR/2004/REC-xmlschema-2-20041028/.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
transfer curve
a curve that defines the relationship between input code values and output values, imaged or printed
3.2
transfer curve set
a set of transfer curves
4 Symbols and abbreviated terms
4.1 Text styles
The following documentation conventions are used.
Names of XML elements are shown in bold type, for example TransferCurve.
Names of XML attributes are shown in italics, for example SpotColorName.
© ISO 2015 – All rights reserved
1

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ISO/DIS 18620
4.2 Data types
All datatypes used in this International Standard are as defined by XML Schema Part 2: Datatypes.
5 Requirements
5.1 XML Namespace
This International Standard relies on XML to ensure clear communication of metadata. It is very likely that
different systems will want to add elements and attributes whose intended use falls outside of this
specification.
Extension of this sort is well supported by XML and the following rules apply:
 All elements and attributes defined by this International Standard shall use the
namespace ’http://www.npes.org/schema/ISO18620/’.
 Vendor specific attributes and elements may be included and when included shall be defined in a vendor-
specific namespace as described in “Namespaces in XML 1.0”.
 Compliant reader applications may safely ignore vendor specific attributes and elements. These attributes
and elements may enable additional functionality in closed environments but shall not change the base
functionality as defined in elements and attributes defined in this standard.
Such proprietary elements and attributes are out of the scope of this International Standard.
5.2 File structure
5.2.1 General
The file is intended to contain a single transfer curve set comprising one or more transfer curves. A schema is
provided in Annex A for information.
The first line of the file shall be:

5.2.2 TransferCurveSet
A single TransferCurveSet element shall be included and shall be as shown in Table 1.
Table 1 — TransferCurveSet element
1
Name Cardinality Data Type Description
xmlns Required anyURI The namespace shall be declared in accordance
with Clause 3 of Namespaces in XML1.0 (Third
Edition) and shall be
‘http://www.npes.org/schema/ISO18620/’.
Creator Optional string Describes the creator of the document. This is
usually the name and version of the authoring
application used.
© ISO 2015 – All rights reserved
2

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ISO/DIS 18620
CreationDate Optional dateTime The date and time when the file was created.
OperatorName Optional string Describes the operator who created the file.
PressName Optional string The name used to describe the press for which
the data has been created.
MediaName Optional string The name used to describe the media for which
the data has been created
Side Optional enumeration The side of the sheet for which the data has been
created. One of Front or Back.
Note that this attribute should be omitted if the
data applies to both sides of the sheet.
MeasurementFile Optional anyURI URI providing the location of one or more
(more than one measurement file(s) from which the data has been
may be provided) derived.
Note that there is no convention specified for the
URI or for the content of the files.
TransferCurveSetID Optional NMTOKEN TransferCurveSet identifier.
The value selected for this ID should be agreed
between stakeholders.
FormPreparationDetails Optional element Provides details of any specific form preparation
configuration, for example the screening family,
gravure engraving parameters, flexo anilox lpi etc
to which the data relates.
This information is likely to be vendor-specific.
PrintingCondition Optional (unless element Metadata describing the printing condition that
match a standard this adjustment applies to.
printing condition)
This shall be
...