1、ICS 17.180.20NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISHSTANDARDColorimetryPart4:CIE1976L*a*b*ColourspaceBS EN ISO11664-4:2011This British Standardwas published under theauthority of the StandardsPolicy and StrategyCommittee on 30 April2010BS EN ISO 11664-4:2011Nati
2、onal forewordThis British Standard is the UK implementation of EN ISO 11664-4:2011.The UK participation in its preparation was entrusted to TechnicalCommittee STI/14, Colour measurement and schedules.A list of organizations represented on this committee can be obtained onrequest to its secretary.Thi
3、s publication does not purport to include all the necessary provisionsof a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.It is identical to ISO 11664-4:2008. It supersedes BS ISO 11664-4:2008, which is with
4、drawn. BSI 2011Amendments/corrigenda issued since publicationDate Comments 30 June 2011 This corrigendum renumbers BS ISO 11664-4:2008 as BS EN ISO 11664-4:2011ISBN 978 0 580 72262 2EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 11664-4 April 2011 ICS 17.180.20 English Version Colorimetry
5、- Part 4: CIE 1976 L*a*b* Colour space (ISO 11664-4:2008) Colorimtrie - Partie 4: Espace chromatique L*a*b* CIE 1976 (ISO 11664-4:2008) Farbmetrik - Teil 4: CIE 1976 L*a*b* Farbenraum (ISO 11664-4:2008) This European Standard was approved by CEN on 17 March 2011. CEN members are bound to comply with
6、 the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Manage
7、ment Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same stat
8、us as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal
9、, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means res
10、erved worldwide for CEN national Members. Ref. No. EN ISO 11664-4:2011: EBS EN ISO 11664-4:2011EN ISO 11664-4:2011 (E)ii Foreword The text of ISO 11664-4:2008 has been prepared by Technical Committee CIE “International Commission on Illumination” of the International Organization for Standardization
11、 (ISO) and has been taken over as EN ISO 11664-4:2011 by Technical Committee CEN/TC 139 “Paints and varnishes” the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest
12、 by October 2011, and conflicting national standards shall be withdrawn at the latest by October 2011. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all suc
13、h patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
14、 Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 11664-4:2008 has been approved by CEN as a EN ISO 11664-4:2011 without any modific
15、ation. BS EN ISO 11664-4:2011EN ISO 11664-4:2011 (E)iii CIE S 014-4/E:2007 CIE 2007 All rights reserved ISO 2011 All rights reserved vStandardColorimetry - Part 4: CIE 1976 L*a*b* Colour Space Colorimtrie - Partie 4: Espace chromatique L*a*b* CIE 1976 Farbmessung - Teil 4: CIE 1976 L*a*b* Farbenraum
16、 CIE Standards are copyrighted and shall not be reproduced in any form, entirely or partly, without the explicit agreement of the CIE. CIE Central Bureau, Vienna CIE S 014-4/E:2007 Kegelgasse 27, A-1030 Vienna, Austria UDC: 535.65:006 Descriptor: Standardisation of colour measurement 535.643.2 Stand
17、ard colorimetric systems CIE S 014-4/E:2007 BS EN ISO 11664-4:2011EN ISO 11664-4:2011 (E)CIE S 014-4/E:2007 vi CIE 2007 All rights reserved ISO 2011 All rights reservednull CIE, 2007 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any for
18、m or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from CIE Central Bureau at the address below. CIE Central Bureau Kegelgasse 27 A-1030 Vienna Austria Tel.: +43 1 714 3187 0 Fax: +43 1 714 3187 18 e-mail: ciecbcie.co.at Web: www.cie.co.a
19、t BS EN ISO 11664-4:2011EN ISO 11664-4:2011 (E)CIE S 014-4/E:2007 CIE 2007 All rights reserved ISO 2011 All rights reserved viiFOREWORD Standards produced by the Commission Internationale de lEclairage (CIE) are a concise documentation of data defining aspects of light and lighting, for which intern
20、ational harmony requires such unique definition. CIE Standards are therefore a primary source of internationally accepted and agreed data, which can be taken, essentially unaltered, into universal standard systems. This CIE Standard has been prepared by the Technical Committee TC 1-57* of Division 1
21、 “Vision and Colour“ and was approved by the National Committees of the CIE. The following ISO and IEC committees and working groups co-operated in the preparation of this standard: IEC TC100/TA2 (Audio, Video and Multimedia Systems) ISO TC6 (Paper, Board and Pulps) ISO TC35/SC9/WG22 (Paint and Varn
22、ishes) ISO TC38/SC1/WG7 (Textiles) ISO TC42 (Photography) ISO TC130 (Graphic Technology) ISO/IEC/JTC1/SC28 (Office Systems)* The chairperson of this TC was A.R. Robertson (CA), members were: P.J. Alessi (US), J.A. Bristow (SE), J. Campos Acosta (ES), R. Connelly (US), J.-F. Decarreau (FR), R. Harold
23、 (US), R. Hirschler (HU), H. Ikeda (JP), B. Jordan (CA), C. Kim (KR), D. McDowell (US), P. McGinley (AU), Y. Ohno (US), M.R. Pointer (GB), K. Richter (DE), G. Rsler (DE), J.D. Schanda (HU), R. Sve (FR), K. Smith (GB), K. Witt (DE), H. Yaguchi (JP), J. Zwinkels (CA). BS EN ISO 11664-4:2011EN ISO 1166
24、4-4:2011 (E)CIE S 014-4/E:2007 viii CIE 2007 All rights reserved ISO 2011 All rights reservedTABLE OF CONTENTS FOREWORD viiINTRODUCTION 11. SCOPE 12. NORMATIVE REFERENCES3. DEFINITIONS, SYMBOLS AND ABBREVIATIONS 14. CALCULATION METHOD 24.1 Basic coordinates 24.2 Correlates of lightness, chroma and h
25、ue 34.3 Colour differences 4ANNEX (INFORMATIVE): REVERSE TRANSFORMATION 6BIBLIOGRAPHY 7BS EN ISO 11664-4:2011EN ISO 11664-4:2011 (E)CIE S 014-4/E:2007 CIE 2007 All rights reserved ISO 2011 All rights reserved 1COLORIMETRY - PART 4: CIE 1976 L*a*b* COLOUR SPACE INTRODUCTION The three-dimensional colo
26、ur space produced by plotting CIE tristimulus values ( X , Y , Z ) in rectangular coordinates is not visually uniform, nor is the ( x , y , Y ) space nor the two-dimensional CIE ( x , y ) chromaticity diagram. Equal distances in these spaces do not represent equally perceptible differences between c
27、olour stimuli. For this reason, in 1976, the CIE introduced and recommended two new spaces (known as CIELAB and CIELUV) whose coordinates are non-linear functions of X , Y and Z . The recommendation was put forward in an attempt to unify the then very diverse practice in uniform colour spaces and as
28、sociated colour difference formulae (Robertson, 1990; CIE, 2004). Both these more-nearly uniform colour spaces have become well accepted and widely used. Numerical values representing approximately the magnitude of colour differences can be described by simple Euclidean distances in the spaces or by
29、 more sophisticated formulae that improve the correlation with the perceived size of differences. The purpose of this CIE Standard is to define procedures for calculating the coordinates of the CIE 1976 L*a*b* (CIELAB) colour space and the Euclidean colour difference values based on these coordinate
30、s. The standard does not cover more sophisticated colour difference formulae based on CIELAB, such as the CMC formula (Clarke et al., 1984), the CIE94 formula (CIE, 1995), the DIN99 formula (DIN, 2001), and the CIEDE2000 formula (CIE, 2001), nor does it cover the alternative uniform colour space, CI
31、ELUV. 1. SCOPE This CIE Standard specifies the method of calculating the coordinates of the CIE 1976 L*a*b* colour space including correlates of lightness, chroma and hue. It includes two methods for calculating Euclidean distances in this space to represent the perceived magnitude of colour differe
32、nces. The Standard is applicable to tristimulus values calculated using colour-matching functions of the CIE 1931 standard colorimetric system or the CIE 1964 standard colorimetric system. The Standard may be used for the specification of colour stimuli perceived as belonging to a reflecting or tran
33、smitting object, where a three-dimensional space more uniform than tristimulus space is required. It does not apply to colour stimuli perceived as belonging to an area that appears to be emitting light as a primary light source, or that appears to be specularly reflecting such light. This Standard d
34、oes apply to self-luminous displays, like cathode ray tubes, if they are being used to simulate reflecting or transmitting objects and if the stimuli are appropriately normalized. 2. NORMATIVE REFERENCES The following referenced documents are indispensable for the application of this document. For d
35、ated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. CIE 17.4-1987. International Lighting Vocabulary (Joint publication IEC/CIE). CIE S 014-1:2006. Colorimetry Part 1 . CIE Standard Colorimetric Ob
36、servers . ISO 11664-1:2007CIE S 014-2:2006. Colorimetry Part 2 . CIE Standard Illuminants. ISO 11664-2:20073. DEFINITIONS, SYMBOLS AND ABBREVIATIONS For the purposes of this International Standard, the terms and definitions given in CIE 17.4-1987 (International Lighting Vocabulary), as amended by th
37、is standard and the following symbols and abbreviations apply. X, Y, Z tristimulus values of test stimulus calculated using the colour-matching functions of the CIE 1931 standard colorimetric system (also known as the CIE 2 standard colorimetric system) BS EN ISO 11664-4:2011EN ISO 11664-4:2011 (E)C
38、IE S 014-4/E:2007 2 CIE 2007 All rights reserved ISO 2011 All rights reservedX n , Yn , Zn tristimulus values of a specific white colour stimulus calculated using the colour-matching functions of the CIE 1931 standard colorimetric system L* CIELAB lightnessa *, b * CIELAB a *, b * coordinates C*ab C
39、IELAB chroma h ab CIELAB hue angle null L* CIELAB lightness difference null a*,null b* CIELAB a*, b* difference null C*ab CIELAB chroma difference null h ab CIELAB hue angle difference null H*ab CIELAB hue difference null E*ab CIELAB colour difference If the character “ null “ is not available, it m
40、ay be replaced by the character “D“. The phrase “CIE 1976 L*a*b*“ and the term “CIELAB“ may be used interchangeably. Where tristimulus values are calculated using the colour-matching functions of the CIE 1964 standard colorimetric system (also known as the CIE 10 standard colorimetric system), a sub
41、script 10 shall be added to all the above symbols. 4. CALCULATION METHOD 4.1 Basic coordinates The CIE 1976 L*a*b* colour space is a three-dimensional, approximately uniform colour space produced by plotting in rectangular coordinates, L*, a*, b *, quantities defined by the equations: nullnull16/116
42、* n nullnull YYfL (1) nullnullnullnullnn /500* YYfXXfa nullnull 2) nullnullnullnullnullnullnn /200* ZZfYYfb nullnull 3) where nullnullnull null 3/1nn / XXXXf null if null null 3n )29/6(/ nullXX (4) nullnull nullnull29/4/)108/841(/ nn nullnull XXXXf if null null 3n )29/6(/ nullXX 5) and nullnullnulln
43、ull3/1nn / YYYYf null if null null 3n )29/6(/ nullYY (6) nullnull nullnull29/4/)108/841(/ nn nullnull YYYYf if null null 3n )29/6(/ nullYY 7) and nullnullnullnull3/1nn / ZZZZf null if null null 3n )29/6(/ nullZZ (8) nullnull nullnull29/4/)108/841(/ nn nullnull ZZZZf if null null 3n )29/6(/ nullZZ 9)
44、 where X, Y, Z are the tristimulus values of the test colour stimulus based on the CIE 1931 standard colorimetric system defined in CIE S 014-1, and X n , Y n , Z n are the corresponding tristimulus values of a specified white stimulus. BS EN ISO 11664-4:2011EN ISO 11664-4:2011 (E)CIE S 014-4/E:2007
45、 CIE 2007 All rights reserved ISO 2011 All rights reserved 3In the case of simulated reflecting or transmitting objects produced on a self-luminous display, all the tristimulus values shall be first normalized by the same factor so that Y would be equal to 100 for an object with 100% reflectance or
46、transmittance. If the angle subtended at the eye by the test stimulus is between about 1 and 4 the tristimulus values X, Y, Z calculated using the colour-matching functions of the CIE 1931 standard colorimetric system should be used. If this angular subtense is greater than 4 the tristimulus values
47、X 10, Y 10, Z 10 calculated using the colour-matching functions of the CIE 1964 standard colorimetric system should be used. The same colour-matching functions and the same specified white stimulus shall be used for all stimuli to be compared with each other. When tristimulus values based on the CIE
48、 1964 standard colorimetric system defined in CIE S 014-1 are used, a subscript 10 shall be added to all the symbols in equations (1) to (9). If the tristimulus values X, Y, Z are obtained by spectrophotometry, the tristimulus values X n , Y n , Z n of the specified white stimulus shall be calculate
49、d using the same method as used for the test stimulus (same colour-matching functions, same range and interval of wavelength, and same bandwidth). If the tristimulus values X, Y, Z are obtained by direct measurement using a tristimulus colorimeter, X n , Y n , Z n shall be measured using the same tristimulus colorimeter and a white reflectance standard calibrated relative to a perfect reflecting diffuser. NOTE 1 For real object colours, the specified
