colour.DIN99_to_Lab

colour.DIN99_to_Lab(Lab_99, k_E=1, k_CH=1, method='DIN99')[source]

Converts from DIN99 colourspace or one of the DIN99b, DIN99c, DIN99d refined formulas according to Cui et al. (2002) to CIE L*a*b* colourspace.

Parameters
  • Lab_99 (array_like) – DIN99 colourspace array.

  • k_E (numeric, optional) – Parametric factor \(K_E\) used to compensate for texture and other specimen presentation effects.

  • k_CH (numeric, optional) – Parametric factor \(K_{CH}\) used to compensate for texture and other specimen presentation effects.

  • method (unicode, optional) – {‘DIN99’, ‘ASTMD2244-07’, ‘DIN99b’, ‘DIN99c’, ‘DIN99d’}, Computation method to choose between the [ASTMInternational07] formula and the refined formulas according to Cui et al. (2002).

Returns

CIE L*a*b* colourspace array.

Return type

ndarray

Notes

Domain

Scale - Reference

Scale - 1

Lab_99

L_99 : [0, 100]

a_99 : [-100, 100]

b_99 : [-100, 100]

L_99 : [0, 1]

a_99 : [-1, 1]

b_99 : [-1, 1]

Range

Scale - Reference

Scale - 1

Lab

L : [0, 100]

a : [-100, 100]

b : [-100, 100]

L : [0, 1]

a : [-1, 1]

b : [-1, 1]

References

[ASTMInternational07], [CLR+02]

Examples

>>> import numpy as np
>>> Lab_99 = np.array([53.22821988, 28.41634656, 3.89839552])
>>> DIN99_to_Lab(Lab_99)  
array([ 41.5278752...,  52.6385830...,  26.9231792...])