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

[Fairchild2011]

Examples

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