GB/T 20147.4-2023 English PDFUS$189.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email. GB/T 20147.4-2023: Colorimetry - Part 4: CIE 1976 L*a*b* colour space Status: Valid
Basic dataStandard ID: GB/T 20147.4-2023 (GB/T20147.4-2023)Description (Translated English): Colorimetry - Part 4: CIE 1976 L*a*b* colour space Sector / Industry: National Standard (Recommended) Classification of Chinese Standard: K71 Classification of International Standard: 29.140.01 Word Count Estimation: 10,128 Date of Issue: 2023-08-06 Date of Implementation: 2024-03-01 Issuing agency(ies): State Administration for Market Regulation, China National Standardization Administration GB/T 20147.4-2023: Colorimetry - Part 4: CIE 1976 L*a*b* colour space---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.ICS 29.140.01 CCSK71 National Standards of People's Republic of China Colorimetry Part 4.CIE1976L*a*b* color space (ISO /CIE11664-4.2019,MOD) Published on 2023-08-06 2024-03-01 Implementation State Administration for Market Regulation Released by the National Standardization Administration Committee Table of contentsPrefaceⅠ Introduction II 1 Scope 1 2 Normative reference documents 1 3 Terms and Definitions 1 4 Symbols and abbreviations1 5 Calculation method 2 5.1 Basic coordinates 2 5.2 Correlation between lightness, chroma and hue3 5.3 Color difference 3 Appendix A (informative) Inverse transformation 5 Reference 6ForewordThis document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1.Structure and Drafting Rules of Standardization Documents" Drafting. This document is Part 4 of GB/T 20147 "Colorimetry". GB/T 20147 has released the following parts. ---Part 3.CIE tristimulus value; ---Part 4.CIE1976L*a*b* color space. This document is modified to adopt ISO /CIE11664-4.2019 "Colorimetry Part 4.CIE1976L*a*b* Color Space". The technical differences between this document and ISO /CIE11664-4.2019 and their reasons are as follows. ---Replaced CIES017 (see Chapter 3) with normatively cited GB/T 2900.65 to adapt to my country's technical conditions, adding Operability. Please note that some content in this document may be subject to patents. The publisher of this document assumes no responsibility for identifying patents. This document is proposed by China Light Industry Federation. This document is under the jurisdiction of the National Lighting Appliances Standardization Technical Committee (SAC/TC224). This document was drafted by. China Institute of Metrology, Foshan Electrical and Lighting Co., Ltd., Zhejiang University, Shenzhen Kangguan Technology Co., Ltd. Co., Ltd., Guangdong Zhongsi Micro Optoelectronics Co., Ltd., Chengdu Hengkun Optoelectronics Technology Co., Ltd., Shenzhen Senbang Lighting Co., Ltd., Shenzhen Shenzhen Arctic Light Technology Co., Ltd., Fudan University, Beijing Electric Light Source Research Institute Co., Ltd., Wuhan University, China Illuminating Society, Wuxi University, Communications and Signal Research Institute of China Academy of Railway Sciences Group Co., Ltd. The main drafters of this document. Liu Hui, Yu Shaotao, Xu Haisong, Ye Wei, Chen Maohua, Cheng Shengpeng, Huo Yongfeng, Li Zhengjun, Xie Qingbo, Lin Yandan, Zhang Bo, Liu Qiang, Xu Xinxin, Huang Sungang, Li Toyota.IntroductionThe three-dimensional color space drawn by the CIE tristimulus values (X, Y, Z) in the Cartesian coordinate system is visually uneven, (x, y, Y) The color space and CIE(x,y) two-dimensional chromaticity diagram are also non-uniform. Equal distances in these spaces do not represent color differences between color stimuli. Differences in color perception. Therefore, in 1976 CIE introduced and recommended two new color spaces (called CIELAB and CIELUV), whose coordinates are nonlinear functions of X, Y and Z. The proposal was introduced to unify the many uniformities arising from practice at the time. Color spaces and color difference formulas. Both of these more uniform color spaces are widely accepted and used. It uses simple Euclidean geometric distance Distance or more complex formulas can be used to approximately describe the size of the color difference to improve the correlation between color perception and color difference. The purpose of this document is to define a process for calculating the chromaticity coordinates of the L*, a*, b* (CIELAB) color space and the Euclidean color difference based on these coordinates. Procedure. This document does not include more complex color difference formulas based on CIELAB color space, such as CMC formula, CIE94 formula, DIN99 formula formula and the CIEDE2000 formula, nor does it include the alternative uniform color space CIELUV. According to the characteristics of different workplaces, GB/T 20147 is planned to be divided into the following six parts. ---Part 1.CIE standard colorimetric observer. The purpose is to specify two sets of color matching functions in colorimetry. ---Part 2.CIE standard lighting body. The purpose is to specify two standard illuminants in colorimetry. ---Part 3.CIE tristimulus value. The purpose is to specify a method for calculating the tristimulus value of a color stimulus of known spectral distribution. ---Part 4.CIE1976L*a*b* color space. The purpose is to specify the calculation of CIE1976L*a*b* color space coordinates method and two methods for calculating Euclidean color difference in this space. ---Part 5.CIE1976L*u*v* color space and u', v' uniform chromaticity scale diagram. The purpose is to specify the calculation CIE1976 L*u*v* color space coordinate method, two methods for calculating Euclidean color difference in this space, and calculating u', v' uniformity Method for chromaticity scale diagram coordinates. ---Part 6.CIEDE2000 color difference formula. The purpose is to specify the method for calculating color difference based on the CIEDE2000 color difference formula. Colorimetry Part 4.CIE1976L*a*b* color space1 ScopeThis document specifies a method for calculating the brightness, chroma and hue related quantities of CIE1976L*a*b* color space coordinates, which includes Two methods for calculating the Euclidean geometric distance that represents color perception differences in color space. This document applies to the CIE1931 standard colorimetric system or the CIE1964 standard colorimetric system that uses color matching functions to calculate tristimulus values. system. This document can be used to describe the color properties of reflective or transmissive objects, in which case a more uniform than tristimulus color space is required three-dimensional color space. This document applies to self-illuminating displays, such as cathode ray tubes, if they are used to simulate color stimuli from reflective or transmissive objects, and and color stimuli were appropriately normalized. This document does not apply to color stimuli that are primarily illuminated by the light source itself or that specularly reflect that luminous area. The method of calculating the inverse transformation is given in Appendix A.2 Normative reference documentsThe contents of the following documents constitute essential provisions of this document through normative references in the text. Among them, the dated quotations For undated referenced documents, only the version corresponding to that date applies to this document; for undated referenced documents, the latest version (including all amendments) applies to this document. GB/T 2900.65 Electrical terminology lighting [GB/T 2900.65-2004, IEC 60050(845).1987, MOD]3 Terms and definitionsThe terms and definitions defined in GB/T 2900.65 apply to this document.4 Symbols and abbreviationsThe following symbols and abbreviations apply to this document. X, Y, Z are calculated using the color matching function of the CIE1931 standard colorimetric system (also known as the CIE2 standard colorimetric system) tristimulus value Xn,Yn,Zn Tristimulus values for a specific white stimulus calculated using the color matching function of the CIE1931 standard colorimetric system L* CIE1976 lightness (CIELAB lightness) a*,b* CIELABa*,b*chromaticity coordinates C*ab CIE1976a,b chroma (CIELAB chroma) hab CIE1976a,b hue angle (CIELAB hue angle) ΔL* CIELAB brightness difference Δa*, Δb* CIELABa*, b* chromaticity coordinate difference ΔC*ab CIELABa*,b*chroma difference Δhab CIELAB hue angle difference ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB/T 20147.4-2023_English be delivered?Answer: Upon your order, we will start to translate GB/T 20147.4-2023_English as soon as possible, and keep you informed of the progress. The lead time is typically 1 ~ 3 working days. 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