The ciespec2uvw function calculates the normalized CIE 1960 Uniform Colour Space (UCS) coordinates ,, for a given spectral power distribution (SPD). Any errors in the data set or in results generated from the reference data or the Lighting Toolbox are not in the liability of the CIE nor me, see licence.
Usage:
[uvw,u,v,w] = ciespec2uvw(lam,spec)
[uvw,u,v,w] = ciespec2uvw(lam,spec)
[uvw,u,v,w] = ciespec2uvw(lam,spec)
Where:
Parameter | Description |
uvw | Is the return scalar/vector containing the normalized UCS values. |
u | Is a scalar containing only the normalized component of the UCS values. |
v | Is a scalar containing only the normalized component of the UCS values. |
w | Is a scalar containing only the normalized component of the UCS values. |
lam | Is a vector specifying the spectral wavelengths steps. |
spec | Is a vector or row-wise matrix containing the spectral power distribution(s). |
Note: For several input spectra use a row-wise matrix.
Examples
Determine the normalized UCS values for standard illuminant ‘D65’:
lam = 360:830;
spec = ciespec(lam,'D65');
uvw = ciespec2uvw(lam,spec)
lam = 360:830;
spec = ciespec(lam,'D65');
uvw = ciespec2uvw(lam,spec)
lam = 360:830; spec = ciespec(lam,'D65'); uvw = ciespec2uvw(lam,spec)
See also: ciespec
Result:
uvw =
0.1978 0.3122 0.4899
uvw =
0.1978 0.3122 0.4899
uvw = 0.1978 0.3122 0.4899
Determine the normalized and component of the UCS values for standard illuminant ‘D65’:
lam = 360:830;
spec = ciespec(lam,'D65');
[~,u,v] = ciespec2uvw(lam,spec)
cie1960(u,v)
lam = 360:830;
spec = ciespec(lam,'D65');
[~,u,v] = ciespec2uvw(lam,spec)
cie1960(u,v)
lam = 360:830; spec = ciespec(lam,'D65'); [~,u,v] = ciespec2uvw(lam,spec) cie1960(u,v)
Result:
u = 0.1978
v = 0.3122
u = 0.1978
v = 0.3122
u = 0.1978 v = 0.3122
Determine the normalized and component of the UCS values for standard illuminants ‘A’ and ‘D65’:
lam = 360:830;
spec = ciespec(lam,{'A','D65'});
[~,u,v] = ciespec2uvw(lam,spec)
lam = 360:830;
spec = ciespec(lam,{'A','D65'});
[~,u,v] = ciespec2uvw(lam,spec)
lam = 360:830; spec = ciespec(lam,{'A','D65'}); [~,u,v] = ciespec2uvw(lam,spec)
See also: ciespec
Result:
u =
0.2560
0.1978
v =
0.3495
0.3122
u =
0.2560
0.1978
v =
0.3495
0.3122
u = 0.2560 0.1978 v = 0.3495 0.3122
References
Projective Transformations of I. C. I. Color Specifications. In: Journal of the Optical Society of America, vol. 27, no. 8, pp. 294-299, 1937, (DOI: 10.1364/JOSA.27.000294).
Colorimetry, 4th Edition. Commission International de l’Éclairage (CIE), Vienna Austria, 2018, ISBN: 978-3-902842-13-8 , (DOI: 10.25039/TR.015.2018).