1、BSI Standards PublicationBS ISO 16760:2014Graphic technology Prepressdata exchange Preparationand visualization of RGBimages to be used in RGB-based graphics arts workflowsBS ISO 16760:2014 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 16760:2014.The UK parti
2、cipation in its preparation was entrusted to TechnicalCommittee PAI/43, Graphic technology.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible fo
3、r its correctapplication. The British Standards Institution 2014. Published by BSI StandardsLimited 2014ISBN 978 0 580 80470 0ICS 35.240.30; 37.100.99Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandard
4、s Policy and Strategy Committee on 31 December 2014.Amendments issued since publicationDate Text affectedBS ISO 16760:2014 ISO 2014Graphic technology Prepress data exchange Preparation and visualization of RGB images to be used in RGB-based graphics arts workflowsTechnologie graphique change de donn
5、es pr-impression Prparation et visualisation dimages RGB utiliser dans les flux de travail des arts graphiques bass sur le RGBINTERNATIONAL STANDARDISO16760First edition2014-12-15Reference numberISO 16760:2014(E)BS ISO 16760:2014ISO 16760:2014(E)ii ISO 2014 All rights reservedCOPYRIGHT PROTECTED DOC
6、UMENT ISO 2014All 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 ca
7、n be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 16760:2014ISO 16760:2014(E)Cont
8、ents PageForeword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 RGB workflow overview 34.1 General . 34.2 RGB Reference Images 34.2.1 Configuration of RGB workflow 34.2.2 Setup and calibration . 44.2.3 Operation procedure 44.2.4 Highlight and shadow point adjustment
9、 . 54.2.5 Additional data requirements 54.3 Print-simulation workflow . 64.3.1 Basic functions of print-simulation workflow . 64.3.2 Ways to achieve basic functions . 75 File format requirements 85.1 Data delivery . 85.2 File format extensions 85.2.1 General 85.2.2 Tiff file . 85.2.3 JPEG (JFIF and
10、EXIF) . 95.3 XMP data for approval status. 106 RGB Reference Prints 116.1 Colour measurement and viewing 116.2 RGB Reference Print requirements 116.2.1 Print substrate colour .116.2.2 Margin information 126.2.3 Print stability .126.2.4 RGB digital control strip . 126.3 Regular checks of RGB Referenc
11、e Printer . 126.3.1 Colour requirements .126.3.2 Determining aim values 136.3.3 Reproduction of vignettes . 136.3.4 Uniformity test 13Annex A (informative) Relationship between highlight and neutral tone value .15Annex B (normative) Viewing condition .17Annex C (normative) RGB Reference Print colour
12、 test chart .18Annex D (informative) Key RGB workflow concepts .23Annex E (informative) Example aim values for common rendering options 29Annex F (normative) Media relative measurements 30Annex G (normative) JPEG extension (JPEG-XT) marker segment .32Bibliography .35 ISO 2014 All rights reserved iii
13、BS ISO 16760:2014ISO 16760:2014(E)ForewordISO (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 inte
14、rested 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 Electrotechnica
15、l 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 docum
16、ents 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 responsibl
17、e 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 t
18、he 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 ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL:
19、Foreword Supplementary information .The committee responsible for this document is ISO/TC 130, Graphic technology.iv ISO 2014 All rights reservedBS ISO 16760:2014ISO 16760:2014(E)IntroductionThis International Standard provides guidelines for image preparation and print simulation in a graphic arts
20、print workflow using RGB images (RGB workflow).Digital still camera (DSC) images have now largely replaced film in the prepress stage of graphic arts printing and most images printed originate from digital cameras. Standard document exchange using PDF/X-4 and PDF/X-5 formats supports the use of RGB
21、content and provides a late binding printing solution where colour conversion is performed only when the document is printed. In this way, all of the original image data can be retained and the conversion for print can be optimised based on the original image content, key image attributes, and the a
22、vailable press colour gamut. These standard document formats provide an ideal framework for RGB workflow.The current best practice for image preparation is to view and adjust images on display. When RGB images are adjusted, proofing mode is selected for a reference printing condition and a calibrate
23、d monitor is used. In this way, users can see an accurate preview of the printed result. This workflow is shown in Figure 1.This documentwas made to showhow RGB Workflowshould work.Figure 1 Current best practice RGB workflowThere are a number of limitations in this workflow: Although it is possible
24、to set up a calibrated monitor and viewing environment defined by Adobe RGB (1998) Colour Image Encoding or ISO/IEC 61966-2-1, it is not usually the case that all stakeholders have a calibrated monitor and the same viewing conditions. In the proposed RGB workflow, an RGB Reference Print can be share
25、d easily among stakeholders. For inexperienced users, critical colour judgement on screen is harder than on print and so the resulting colour might not be what the user desires. The proposed RGB workflow is described for both experts and inexperienced users. The intended printing condition needs to
26、be communicated to every stakeholder by independent means and all users need to know how to set up a viewing environment appropriate to the printing condition. In the proposed RGB workflow, the intended printing condition is included as metadata with the image. ISO 2014 All rights reserved vBS ISO 1
27、6760:2014ISO 16760:2014(E) The approval status of an image is not clearly shown. In the proposed RGB workflow, the approval status is included as metadata with the image.The proposed RGB workflow addresses these limitations as shown in Figure 2. In this RGB workflow, candidate images are printed on
28、an RGB Reference Printer that has been calibrated to produce an accurate simulation of the intended printing condition. These printed images are checked in a controlled print viewing environment and, if necessary, further adjustments are made until the intended print result is achieved. When RGB ima
29、ge files are created and checked in this way, metadata that describes the intended printing condition and the image approval status is added.Digitalcamerascene captureand renderingRGBReferenceImageRGB ReferencePrintcreationRetouchImageapproved?DocumentcreationDigitalprinterConventionalpressDigitalpr
30、essOtherCaptureImage preparation Documentcreation and printingAdd referenceprintersOutputIntentR GBCalibrated to simulateintended printingconditionAdd Output intent metadatacorresponding tointended print conditionFigure 2 RGB workflow from scene to printing via RGB image dataCareful preparation of R
31、GB images holds the key to a successful RGB workflow. There are a number of aspects to consider when preparing images for print, including the identification of image highlight and shadow points and the careful mapping of important image colours into the colour gamut of the printing press. Since mos
32、t printing processes have a significantly different colour gamut size and shape from the set of colours represented in an image, care needs to be taken when editing images so that important colours are retained. This is done most effectively by associating the RGB image with a CMYK press profile. Th
33、is International Standard describes how to prepare these RGB images. Figure 2 shows the RGB workflow described by this International Standard and RGB is the prepared RGB image.NOTE For the proposed workflow, although a calibrated soft proof viewing environment is not required, the calibration of a r
34、eference printer is required and this print needs to be viewed in a standard calibrated viewing environment. If possible, printers with automatic calibration need to be used in cases where users are not familiar with the calibration process.When this workflow is adopted, images can be prepared and i
35、ncorporated in documents which can be printed on multiple printing systems producing prints with a similar appearance.When the RGB image data are approved based on a hardcopy print, consistent judgement can be made.This workflow is supported by the PDF/X-4 and PDF/X-5 standard document formats. Docu
36、ments are expected to be approved using ISO 12647-8 (validation print) or ISO 12647-7 (contract proof).It is envisaged that printing systems will be developed to produce prints that conform to this International Standard. It can be the case that systems that already conform to the requirements of IS
37、O 12647-8 or ISO 12647-7 will be extended to produce RGB Reference Prints. Such systems will provide an easy means for users to ensure that images and the documents that include these images are printed reliably.vi ISO 2014 All rights reservedBS ISO 16760:2014ISO 16760:2014(E)This workflow relates t
38、o images that are destined for four-colour commercial printing. Photographers need to be aware that alternative file versions of an image can still be required for specialized printing conditions.Annex D provides further details of key RGB workflow concepts. ISO 2014 All rights reserved viiBS ISO 16
39、760:2014BS ISO 16760:2014Graphic technology Prepress data exchange Preparation and visualization of RGB images to be used in RGB-based graphics arts workflows1 ScopeThis International Standard specifies requirements for an RGB workflow for graphic arts printing based on the use of reflection prints
40、(RGB Reference Prints) as the evaluation vehicle for coloured images. It provides guidelines on the creation of print-targeted RGB images (RGB Reference Images) and simulation prints.This International Standard requires the identification of a pair of ICC profiles for each image: an image profile an
41、d a profile describing the reference printing system. These profiles provide individual colour transformations for gamut mapping and colour separation. This International Standard does not provide any guidance as to how these gamut mapping or colour separation transforms can be specified.2 Normative
42、 referencesThe 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) appli
43、es.ISO 3664:2009, Graphic technology and photography Viewing conditionsISO 11664-4 (CIE S 014-4/E:2007), Colorimetry Part 4: CIE 1976 L*a*b* Colour spaceISO 12234-1, Electronic still-picture imaging Removable memory Part 1: Basic removable-memory modelISO 13655, Graphic technology Spectral measureme
44、nt and colorimetric computation for graphic arts imagesISO 15076-1:2010, Image technology colour management Architecture, profile format and data structure Part 1: Based on ICC.1:2010ISO 15790, Graphic technology and photography Certified reference materials for reflection and transmission metrology
45、 Documentation and procedures for use, including determination of combined standard uncertaintyISO 186191), Image technology colour management Black point compensationISO 194452), Graphic technology Metadata for graphic arts workflow XMP metadata for image and document proofingISO/IEC 10918-1, Infor
46、mation technology Digital compression and coding of continuous-tone still images: Requirements and guidelines Part 1ISO/CIE 11664-6 (CIE S 014-6/E:2013), Colorimetry Part 6: CIEDE2000 Colour-difference formulaTIFF, Revision 6.0 Final, Adobe Systems Incorporated, June 3, 19923 Terms and definitionsFo
47、r the purposes of this document, the following terms and definitions apply.1) Under preparation.2) Under preparation.INTERNATIONAL STANDARD ISO 16760:2014(E) ISO 2014 All rights reserved 1BS ISO 16760:2014ISO 16760:2014(E)3.1RGB colour spacethree-component colour encoding defined by a linear transfo
48、rm from CIE XYZNote 1 to entry: Such a transform can be specified as a 3 3 matrix, and the transform between XYZ and additive RGB is then performed by multiplying by this matrix or its inverse.Note 2 to entry: Adobe RGB (1998) is an example of an RGB colour space.3.2characterized printing conditionp
49、rinting condition for which process control aims are defined and for which the relationship between input data (printing-tone values, usually CMYK) and the colorimetry of the printed image is documentedNote 1 to entry: The relationship between input data (printing tone values) and the colorimetry of the printed image is commonly referred to as characterization.Note 2 to entry: It is generally preferred that the process control aims of the printing condition and the associated characteriza
