CIE标准色度学系统介绍VIP专享VIP免费

第1页共17页编号：时间：2021年x月x日书山有路勤为径，学海无涯苦作舟页码：第1页共17页二、1931CIE-XYZ标准色度系统所谓1931CIE-XYZ系统，就是在RGB系统的基础上，用数学方法，选用三个理想的原色来代替实际的三原色，从而将CIE-RGB系统中的光谱三刺激值和色度坐标r、g、b均变为正值。（一）、CIE-RGB系统与CIE-XYZ系统的转换关系选择三个理想的原色（三刺激值）X、Y、Z，X代表红原色,Y代表绿原色,Z代表蓝原色,这三个原色不是物理上的真实色，而是虚构的假想色。它们在图5-27中的色度坐标分别为：rgbX1.275-0.2780.003Y-1.7392.767-0.028Z-0.7430.1411.602从图5-27中可以看到由XYZ形成的虚线三角形将整个光谱轨迹包含在内。因此整个光谱色变成了以XYZ三角形作为色域的域内色。在XYZ系统中所得到的光谱三刺激值、、、和色度坐标x、y、z将完全变成正值。经数学变换，两组颜色空间的三刺激值有以下关系：X=0.490R+0.310G+0.200BY=0.177R+0.812G+0.011B…………………………（5-8）Z=0.010G+0.990B两组颜色空间色度坐标的相互转换关系为：x=（0.490r+0.310g+0.200b）/（0.667r+1.132g+1.200b）y=（0.117r+0.812g+0.010b）/（0.667r+1.132g+1.200b）………………(5-9)z=（0.000r+0.010g+0.990b）/（0.667r+1.132g+1.200b）这就是我们通常用来进行变换的关系式，所以，只要知道某一颜色的色度坐标r、g、b，即可以求出它们在新设想的三原色XYZ颜色空间的的色度坐标x、y、z。通过式（5-9）的变换，对光谱色或一切自然界的色彩而言，变换后的色度坐标均为正值，而且等能白光的色度坐标仍然是（0.33，0.33），没有改变。表5-3是由CIE-RGB系统按表5-2中的数据，由式（5-9）计算的结果。从表5-3中可以看到所有光谱色度坐标x(l)，y(l)，z(l)的数值均为正值。光谱色度坐标光谱三刺激值第2页共17页第1页共17页编号：时间：2021年x月x日书山有路勤为径，学海无涯苦作舟页码：第2页共17页l（毫微米）xyz3800.17410.00500.82090.001450.00000.00653850.17400.00500.82100.00220.00010.01053900.17380.00490.82130.00420.00010.02013950.17360.00490.82150.00760.00020.03624000.17330.00480.82190.01430.00040.06794050.17300.00480.82220.02320.00060.11024100.17260.00480.82260.04350.00120.20744150.17210.00480.82310.07760.00220.37134200.17140.00510.82350.13440.00400.64564250.17030.00580.82390.21480.00731.03914300.16890.00690.82420.28390.01161.38564350.16690.00860.82450.32850.01681.62304400.16440.01090.82470.34830.02301.74714450.16110.01380.82510.34810.02981.78264500.15660.01770.82570.33620.03801.77214550.15100.02270.82630.31870.04801.74414600.14400.02970.82630.29080.06001.66924650.13550.03990.82460.25110.07391.52814700.12410.05780.81810.19540.09101.28764750.10960.08680.80360.14210.11261.04194800.09130.13270.77600.09560.13900.81304850.06870.20070.73060.05800.16930.61624900.04540.29500.65960.03200.20800.46524950.02350.41270.56380.01470.25860.35335000.00820.53840.45340.00490.32300.27205050.00390.65480.34130.00240.40730.2123第3页共17页第2页共17页编号：时间：2021年x月x日书山有路勤为径，学海无涯苦作舟页码：第3页共17页5100.01390.75020.23590.00930.50300.15825150.03890.81200.14910.02910.60820.11175200.07430.83380.09190.06330.71000.07825250.11420.82620.05960.10960.79320.05735300.15470.80590.03940.16550.86200.04225350.19290.78160.02550.22570.91490.02985400.22960.75430.01610.29040.95400.02035450.26580.72430.00990.35970.98030.01345500.30160.69230.00610.43340.99500.00875550.33730.65890.00380.51211.00000.00575600.37310.62450.00240.59450.99500.00395650.40870.58960.00170.67840.97860.00275700.44410.55470.00120.76210.95200.00215750.47880.52020.00100.84250.91540.00105800.51250.48660.00090.91630.87000.00175850.54480.45440.00080.97860.81630.00145900.57520.42420.00061.02630.75...