色彩标准转换_Color SPACE

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CIE Standard Illuminants
Illuminant A B C X 109.85 99.09 98.07 Y 100 100 100 Z 35.58 85.31 118.23 Wx 0.448 0.348 0.310 Wy 0.407 0.352 0.316
D50
D55 D65 D75 E
Color matching experimental setup
Test Light
Primary Mixture
Tristimulus values
700(RO), 546.1(GO), and 435.8 nm (BO), with units such that equal amounts of the three stimuli are required to match light from the equi-energy illuminant Se
X K S ( )R ( ) x ( ) d Y K S ( )R ( ) y ( ) d Z K S ( )R ( ) z ( )d
0.31 0.20 R O X 0.49 Y 0.17697 0.81240 0.01063 G O Z 0.00 0.01 0.99 Байду номын сангаасBO
5
Light source : fluorescent lamp
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Light source : Flash Light
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Commercial Lights
Correlated colour temperatures of
Source Typical north-sky light Typical average daylight Artificial Daylight fluorescent lamps (*1) Xenon (electronic flash or continuous) Typical sunlight plus skylight Blue flash-bulbs Carbon arc (for projectors) Sunlight at solar altitude 20° Cool White fluorescent lamps (*2) Sunlight at solar altitude 10° Clear flash-bulbs White fluorescent lamps (*3) Photo-flood tungsten lamps Tungsten-halogen lamps Projection tungsten lamps Studio tungsten lamps Warm White fluorescent lamps Floodlighting tungsten lamps Kelvins 7500 6500 6500 6000 5500 5500 5000 4700 4300 4000 3800 3500 3400 3300 3200 3200 3000 3000 Mireds 133 154 154 167 182 182 200 213 233 250 263 286 294 303 312 312 333 333
0.4 0.3 Tristimulus values b 0.2 0.1 0.0 -0.1 380 480 580 680 Wavelength (nm) 780 g
r ( ) r ( ) /( r ( ) g ( ) b( ))
r
g ( ) g ( ) /( r ( ) g ( ) b( )) b( ) b( ) /( r ( ) g ( ) b( ))
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CIE 1931 Standard Observer (r, g, b)
The following color matching functions were obtained. There were problems with the r, g, b color matching functions. Negative values meant that the color had to be added to the test light before the two halves could be balanced.
Relative spectral power distribution curves of daylight typical of various weather condi- tions as received on a nearly vertical surface facing towards the sun. O: overcast; C: clear; LC: light cloud; H: hazy (Condit and Grum, 1964). Relative spectral power distribution curves of daylight with clear sky for various solar altitudes, as received on a nearly vertical surface facing towards the sun (Condit and Grum, 1964).
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Munsell
Hue_Value / Chroma
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RGB / CMY color
One of the simplest color models. Cartesian coordinates for each color; an axis is each assigned to the three primary colors red (R), green (G), and blue (B).
480
580 680 Wavelength (nm)
780
1931 standard observer (2° observer).
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Standard Observer : 2° vs 10° in xy
The colour-matching functions for the CIE matching stimuli X, Y, and Z. Full lines: for the 2° Standard Observer, using X, Y, Z; broken lines: for the 10° Standard Observer, using X10, Y10, Z10. The x, y triangle for the 2° Standard Observer (full line) and for the 10° Standard Observer (broken line) using x10, y10.
X Y ; y ; XYZ XYZ Z z 1 x y XYZ x
r
Tristimulus values
R R GB G g R GB
2.0 z 1.5 y 1.0 x
0.5
0.0 380 The positions of the matching stimuli X, Y, and Z in the Standard Observer colour triangle Ro Go Bo
1931 standard observer (2° observer).
* CIE:Commission Internationale de l'Eclairage
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Color-matching function
for 1931 Standard Observer : spectrum with primaries of Bo=435.8nm, Go=546.1 nm, and Ro=700 nm, each wavelength of the equal energy , the average of 17 color-normal observers having matched on a bipartite 2° field, surrounded by darkness. Special properties of X, Y, Z:- Imaginary (non-physical) primary. All luminance information is contributed by Y. Linearly related to R, G, B.Non-negative values for all tristimulus values.
Corresponds to the principles of additive colors. Other colors are represented as an additive mix of R, G, and B. Ideal for use in computers.
Blue (0,0,1)
*1 Sometimes called North-light or Colour Matching lamps *2 Sometimes called Daylight lamps *3 Sometimes called Natural lamps
Domestic tungsten lamps (100 to 200 W.)
Light source :
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Sunlight
角度 ( ° ) 0 60 70.5 75.5 78.5
輝度(cd/m ) 150,000 125,000 100,000 80,000 65,000
色温度(K) 5,600 5,100 4,700 4,400 4,100
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Sunlight spectrum
96.42
95.68 95.04 94.96
100
100 100 100
82.49
92.14 108.89 122.61
0.346
0.332 0.313 0.299 0.333
0.359
0.347 0.329 0.315 0.333
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CIE Standard Illuminants spectrum
Domestic tungsten lamps (40 to 60 W.) Sunlight at sunset Candle flame
2900
2800 2000 1900
345
357 500 526
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Color model
Munsell RGB (Red, Green, Blue) based CMY(K) (Cyan, Magenta, Yellow, Black) based Luminance - Chrominance based
Green Channel
Blue Channel
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CMY Image Data
Full Color Image Cyan Image (1-R)
Magenta Image (1-G)
Yellow Image (1-B)
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Color Matching Experiment
Observer views a split screen of pure white (100% reflectance). On one half, a test lamp casts a pure spectral color on the screen. On the other, three lamps emitting variable amounts of red, green, and blue light are adjusted to match the color of the test light. The amounts of red, green and blue light used to match the pure colors were recorded when an identical match was obtained. The RGB tristimulus values for each distinct color was obtained this way.
Cyan (0,1,1)
Magenta (1,0,1)
White (1,1,1)
Black (0,0,0) Green (0,1,0) Red (1,0,0) Yellow (1,1,0)
*Red, Green, and Blue
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RGB Image Data
Full Color Image Red Channel