colour.Lab_to_DIN99#

colour.Lab_to_DIN99(Lab: ArrayLike, k_E: float = 1, k_CH: float = 1, method: Literal['ASTMD2244-07', 'DIN99', 'DIN99b', 'DIN99c', 'DIN99d'] | str = 'DIN99') NDArrayFloat[source]#

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

Parameters:
  • Lab (ArrayLike) – CIE L*a*b* colourspace array.

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

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

  • method (Literal['ASTMD2244-07', 'DIN99', 'DIN99b', 'DIN99c', 'DIN99d'] | str) – Computation method to choose between the [ASTMInternational07] formula and the refined formulas according to Cui et al. (2002).

Returns:

DIN99 colourspace array.

Return type:

numpy.ndarray

Notes

Domain

Scale - Reference

Scale - 1

Lab

L : [0, 100]

a : [-100, 100]

b : [-100, 100]

L : [0, 1]

a : [-1, 1]

b : [-1, 1]

Range

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]

References

[ASTMInternational07], [CLR+02]

Examples

>>> import numpy as np
>>> Lab = np.array([41.52787529, 52.63858304, 26.92317922])
>>> Lab_to_DIN99(Lab)  
array([ 53.2282198...,  28.4163465...,   3.8983955...])