colour.colorimetry.lightness_Fairchild2011¶

colour.colorimetry.lightness_Fairchild2011(Y, epsilon=0.474, method='hdr-CIELAB')[source]¶

Computes Lightness \(L_{hdr}\) of given luminance \(Y\) using Fairchild and Chen (2011) method according to Michealis-Menten kinetics.

Parameters:	Y (array_like) – luminance \(Y\). epsilon (numeric or array_like, optional) – \(\epsilon\) exponent. method (unicode, optional) – {‘hdr-CIELAB’, ‘hdr-IPT’}, Lightness \(L_{hdr}\) computation method.
Returns:	Lightness \(L_{hdr}\).
Return type:	array_like

Notes

Domain	Scale - Reference	Scale - 1
`Y`	[0, 1]	[0, 1]

Range	Scale - Reference	Scale - 1
`L_hdr`	[0, 100]	[0, 1]

References

[FC11]

Examples

>>> lightness_Fairchild2011(12.19722535 / 100)  # doctest: +ELLIPSIS
51.8529584...
>>> lightness_Fairchild2011(12.19722535 / 100, method='hdr-IPT')
... # doctest: +ELLIPSIS
51.6431084...