1、BRITISH STANDARD BS EN 61966-8:2001 IEC 61966-8:2001 Multimedia systems and equipment Colour measurement and management Part 8: Multimedia colour scanners The European Standard EN 61966-8:2001 has the status of a British Standard ICS 33.160.60; 35.180 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERM
2、ITTED BY COPYRIGHT LAWBS EN 61966-8:2001 This British Standard, having been prepared under the direction of the Electrotechnical Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 03 December 2001 BSI 03 December 2001 ISBN 0 580
3、38732 1 National foreword This British Standard is the official English language version of EN 61966-8:2001. It is identical with IEC 61966-8:2001. The UK participation in its preparation was entrusted to Technical Committee EPL/100, Audio, video and multimedia systems and equipment, which has the r
4、esponsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. From 1 January 1997, all IEC publications have the number 60000 added to the old number. For instance, IEC 27-1 has been renumbered as IEC 60027-1. For a period of time during the cha
5、nge over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “
6、International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance wi
7、th a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and Eur
8、opean developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 38, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Ame
9、ndments issued since publication Amd. No. Date CommentsEUROPEAN STANDARD EN 61966-8 NORME EUROPENNE EUROPISCHE NORM May 2001 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secret
10、ariat: rue de Stassart 35, B - 1050 Brussels 2001 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61966-8:2001 E ICS 33.160.60; 35.180 English version Multimedia systems and equipment - Colour measurement and management Part 8: Mu
11、ltimedia colour scanners (IEC 61966-8:2001) Systmes et appareils multimdia - Mesure et gestion de la couleur Partie 8: Numriseurs couleur (CEI 61966-8:2001) Multimediasysteme und -gerte - Farbmessung und Farbmanagement Teil 8: Multimedia-Farbscanner (IEC 61966-8:2001) This European Standard was appr
12、oved by CENELEC on 2001-04-01. CENELEC members are bound to comply with 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 nati
13、onal standards may be obtained on application to the Central Secretariat or to any CENELEC 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 CENELEC member into its own languag
14、e and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spa
15、in, Sweden, Switzerland and United Kingdom.Foreword The text of document 100/192/FDIS, future edition 1 of IEC 61966-8, prepared by IEC TC 100, Audio, video and multimedia systems and equipment, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61966-8 on 2001-04-01. T
16、he following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (don) 2002-01-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2004-04-01 Annexes des
17、ignated “normative“ are part of the body of the standard. Annexes designated “informative“ are given for information only. In this standard, annexes A, B and ZA are normative and annex C is informative. Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard I
18、EC 61966-8:2001 was approved by CENELEC as a European Standard without any modification. _ Page2 EN619668:2001 BSI03DecemberCONTENTS Page INTRODUCTION 6 1 Scope and object. 9 2 Normative references. 9 3 Terms and definitions .10 4 Letters and symbols11 5 Conditions 11 5.1 General conditions.11 5.2 O
19、utput digital image data.12 6 Measurement equipment and target of scan12 6.1 Spectrophotometer 12 6.2 Spectroradiometer .12 6.3 Specification of the target 13 7 Spectral power distribution of the built-in light source .15 7.1 Characteristics to be measured .15 7.2 Measurement conditions15 7.3 Presen
20、tation of results.15 8 Tone characteristics17 8.1 Characteristics to be measured .17 8.2 Measurement conditions17 8.3 Method of measurement 17 8.4 Calculation of results .17 8.5 Presentation of results.18 9 Inverse tone characteristics 19 9.1 Characteristics to be calculated 19 9.2 Method of calcula
21、tion.19 9.3 Presentation of results.20 10 Spectral responsivity characteristics .20 10.1 Characteristics to be measured .20 10.2 Measurement conditions21 10.3 Method of measurement 21 10.4 Presentation of results.21 11 Spatial non-uniformity.25 11.1 Characteristics to be measured .25 11.2 Measuremen
22、t conditions25 11.3 Method of measurement 25 11.4 Presentation of results.27 12 Mid-term instability28 12.1 Characteristics to be measured .28 12.2 Measurement conditions28 12.3 Method of measurement 29 12.4 Presentation of results.29 Page3 EN619668:2001 BSI03December 4 619-668 EI:C002(1)E 13 Large
23、area spatial crosstalk 29 13.1 Characteristics to be measured .29 13.2 Measurement conditions29 13.3 Method of measurement 30 13.4 Presentation of results.31 Annex A (normative) Estimation of multiband of wavelength sensitivities32 A.1 Quantities to be estimated .32 A.2 Input to the algorithm.32 A.3
24、 Output to the algorithm 33 A.4 Internal variables of the algorithm33 A.5 Estimation algorithm 33 Annex B (normative) Scanner model output data from estimated multiband sensitivities.35 Annex C (informative) Examples for the application of the spectral characteristics .36 C.1 Calculation of the ICC
25、profiles .36 C.2 Calculation of an optimized conversion for sRGB colour space36 Annex ZA (normative) Normative references to international publications with their corresponding European publications .38 Bibliography37 Figure 1 Specification of the target for characterization of multimedia colour sca
26、nners .13 Figure 2 Example of graphical representation of multiband spectral reflection of a colour patch 14 Figure 3 Scanning area and the points of measurement .15 Figure 4 Example of the normalized spectral power distribution of the built-in light source.16 Figure 5 Example of reporting form of t
27、one characteristics, light flux vs. output data 19 Figure 6 An example of multiband spectral responsivity, R s , G s and B s 24 Figure 7 Example of reporting form of the overall multiband spectral responsitivity, n s S n R , n s S n Gand n s S n B 25 Figure 8 Measurement points for spatial non-unifo
28、rmity26 Figure 9 Example of report of mid-term instability.29 Figure 10 Target for the measurement of spatial crosstalk .30 Table 1 Example of reporting form of a spectral table.14 Table 2 Example of multiband spectral characteristics of the light source.16 Table 3 Example of reporting form of the p
29、olynomial coefficients of the red, green and blue channel.18 Table 4 Example of reporting form of the polynomial coefficients of the red, green and blue channels.20 Table 5 Example of reporting form of the multiband responsitivity characteristics.22 Table 6 Reporting form for the measurement of spat
30、ial non-uniformity .28 Table 7 Reporting form for the measurement of spatial crosstalk31 Page4 EN619668:2001 BSI03December169-668 EI:C002(1)E 5 Table 8 Reporting form of average data and maximum crosstalk given by relative maximum differences and relative standard deviations of data in red, green an
31、d blue channels (8 bits per channel) 31 Page5 EN619668:2001 BSI03December 6 619-668 EI:C002(1)E INTRODUCTION This introduction is intended to distinguish the field of application of ISO 12641 and IEC 61966-8. In order to standardize the calibration procedure for input scanners used in the printing a
32、nd prepress industry, ISO 12641 was published in 1997. This part of IEC 61966 targets colour scanners for multimedia applications by providing characterization data necessary for colour management in open multimedia systems. It characterizes any multimedia colour scanners for consumer use, typically
33、 being connected to personal computers so as to capture colour images and display the colour information, either locally or distributed worldwide. In such applications, colour management is important. Any red green blue data should have their colorimetric attributes clearly specified. The characteri
34、zation data reported from this part of IEC 61966 will be used for the calculation of equipment specific colorimetric characterization so that colour management in open systems can be conducted. The capture of colour information in a prepress input scanner usually assumes that the source is a positiv
35、e film (transparent) original. The second most common type of original is positive photographic printing paper (reflective). Recently, prepress input scanners can support various types of reflective originals in addition to printing paper and can also capture an image directly from a negative film,
36、although this is not yet very common. Due to these circumstances, ISO 12641 was established for prepress digital data exchange corresponding to transparent and reflective originals. However, a standard colour target for transparent film negative originals has not yet been established. Spectral sensi
37、tivity characteristics of prepress scanners are not derived from the calculation based on a special colour system or the spectral distribution of printing ink; but are base signals relatively close to the three primary colours (red, green, blue) acquired for calibration purposes. The characteristics
38、 of the prepress input scanners are guaranteed by the experience of the operator or the sophistication of the colour processing application so that subtle variations among the colours appear in the printed result. In fact, printing and prepress scanners have many settings that are made available to
39、professional users, and the operator can control the input scanner characteristics in a non-linear fashion to suit their objectives. In older input scanners, these controls were part of the stand-alone scanner system itself. For the scanners of the printing industry, these controls are typically par
40、t of the colour processing application software which processes the signals after capture and transfers them to the general purpose computer (workstation or server). In other words, a highly experienced and skilled operator can adjust the settings to freely change scanner characteristics such as ton
41、e and colour separation as he desires. Furthermore, scanner characteristics can be changed to correct and compensate for the characteristics of the original image target, such as colour fogging, as well as absorb them, and the operator can even change scanner colour separation conditions (typically
42、cyan, yellow, magenta and black) in anticipation of the later printing process so as to obtain the most feasible printed result. As such, on the site of the prepress scanner, good colour separation (reproduction) is and has been dependent on the skill of the operator. All prepress input scanners sho
43、w variation in colour sensitivity characteristics depending on types, manufacturers, manufactured time and condition. Prepress input scanners tend to show less variation than other general-purpose multimedia colour scanners because of their usage in critical colour capturing in a closed system in co
44、mparison with the worldwide open system such as the Internet. There has never been an attempt to standardize the colour character- istics of prepress input scanners put on the market by different manufacturers. Page6 EN619668:2001 BSI03December169-668 EI:C002(1)E 7 However, it is demanded that the p
45、rinting process should produce essentially the same results from the same original regardless of the input scanner used. This demand has been accomplished by the skill of the operator. For this reason, the process of scanning, including colour processing for the raw data, should involve the human op
46、erator, and the total system be considered as one system. In this human-machine interaction system, the characteristics can be understood as unified or standardized. Under these circumstances, and in consideration of the actual work process, ISO/TC 130 (Graphic technology) has established a method u
47、sing a colour target as stipulated in ISO 12641 for prepress input scanner calibration that includes functions capable of handling colour changes accompanying local distortions in colour regions. These targets for both positive reflective material (photographic printing paper) and positive transmiss
48、ion material (photographic film) are implemented by the photographic manufacturers on their specific materials of their particular products. Multimedia colour scanners for general use which are much less expensive in comparison with prepress input scanners, are available for small office/home office
49、 personal computers. Targets for scanning are not specified as in prepress input scanners. Images of natural objects such as the petals of violets, green plants or human skin will be most important. As many of the users of multimedia colour scanners are not colour experts, it is preferable to have an automatic system requiring minimal adjustment. The manufacturers of this type of colour scanner do not provide colorimetric specifications of the red g
