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whitepoint

XYZ color values of standard illuminants

Description

example

xyz = whitepoint returns the XYZ value corresponding to the default ICC white reference illuminant, scaled so that Y = 1.

example

xyz = whitepoint(illuminant) returns the XYZ value corresponding to the white reference illuminant, illuminant, scaled so that Y = 1.

Examples

Get XYZ Value of ICC Illuminant

Return the XYZ color space representation of the default white reference illuminant, 'icc'.

wp_icc = whitepoint
wp_icc =

    0.9642    1.0000    0.8249

Note that the second element, corresponding to the Y value, is 1.

Get XYZ Value of d65 Illuminant

Return the XYZ color space representation of the 'd65' white reference illuminant.

wp_d65 = whitepoint('d65')
wp_d65 =

    0.9504    1.0000    1.0888

Input Arguments

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White reference illuminant, specified as one of these values:

ValueWhite Point
'a'

CIE standard illuminant A, [1.0985, 1.0000, 0.3558]. Simulates typical, domestic, tungsten-filament lighting with correlated color temperature of 2856 K. 

'c'CIE standard illuminant C, [0.9807, 1.0000, 1.1822]. Simulates average or north sky daylight with correlated color temperature of 6774 K. Deprecated by CIE.
'e'Equal-energy radiator, [1.000, 1.000, 1.000]. Useful as a theoretical reference.
'd50'CIE standard illuminant D50, [0.9642, 1.0000, 0.8251]. Simulates warm daylight at sunrise or sunset with correlated color temperature of 5003 K. Also known as horizon light.

'd55'

CIE standard illuminant D55, [0.9568, 1.0000, 0.9214]. Simulates mid-morning or mid-afternoon daylight with correlated color temperature of 5500 K.  

'd65'CIE standard illuminant D65, [0.9504, 1.0000, 1.0888]. Simulates noon daylight with correlated color temperature of 6504 K. 
'icc'Profile Connection Space (PCS) illuminant used in ICC profiles. Approximation of [0.9642, 1.000, 0.8249] using fixed-point, signed, 32-bit numbers with 16 fractional bits. Actual value: [31595,32768, 27030]/32768.

Data Types: char | string

Output Arguments

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XYZ values corresponding to the illuminant, returned as a 3-element numeric row vector. The values are scaled so that Y = 1.

Data Types: double

Introduced before R2006a