colour.colorimetry.lightness_Fairchild2011

colour.colorimetry.lightness_Fairchild2011(Y, epsilon=0.71, method=u'hdr-CIELAB')

Computes Lightness \(L_{hdr}\) of given luminance \(Y\) using Fairchild and Chen (2011) method accordingly 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

Warning

The input domain of that definition is non standard!

Notes

• Input luminance \(Y\) is in domain [0, \(\infty\)].

References

• [FC11]

Examples

>>> lightness_Fairchild2011(10.08 / 100)  
26.45950981...
>>> lightness_Fairchild2011(10.08 / 100, method='hdr-IPT')
... 
26.3524672...