colour.delta_E¶
-
colour.
delta_E
(a, b, method='CIE 2000', **kwargs)[source]¶ Returns the difference \(\Delta E_{ab}\) between two given CIE L*a*b* or \(J'a'b'\) colourspace arrays using given method.
- Parameters
a (array_like) – CIE L*a*b* or \(J'a'b'\) colourspace array \(a\).
b (array_like) – CIE L*a*b* or \(J'a'b'\) colourspace array \(b\).
method (unicode, optional) – {‘CIE 2000’, ‘CIE 1976’, ‘CIE 1994’, ‘CMC’, ‘CAM02-LCD’, ‘CAM02-SCD’, ‘CAM02-UCS’, ‘CAM16-LCD’, ‘CAM16-SCD’, ‘CAM16-UCS’, ‘DIN99’} Computation method.
- Other Parameters
textiles (bool, optional) – {
colour.difference.delta_E_CIE1994()
,colour.difference.delta_E_CIE2000()
,colour.difference.delta_E_DIN99()
}, Textiles application specific parametric factors \(k_L=2,\ k_C=k_H=1,\ k_1=0.048,\ k_2=0.014,\ k_E=2,\ k_CH=0.5\) weights are used instead of \(k_L=k_C=k_H=1,\ k_1=0.045,\ k_2=0.015,\ k_E=k_CH=1.0\).l (numeric, optional) – {
colour.difference.delta_E_CIE2000()
}, Lightness weighting factor.c (numeric, optional) – {
colour.difference.delta_E_CIE2000()
}, Chroma weighting factor.
- Returns
Colour difference \(\Delta E_{ab}\).
- Return type
numeric or ndarray
References
[ASTMInternational07], [LLW+17], [Lin03a], [Lin11], [Lin09b], [Lin09c], [LCL06], [Mel13], [Wik08c]
Examples
>>> import numpy as np >>> a = np.array([100.00000000, 21.57210357, 272.22819350]) >>> b = np.array([100.00000000, 426.67945353, 72.39590835]) >>> delta_E(a, b) 94.0356490... >>> delta_E(a, b, method='CIE 2000') 94.0356490... >>> delta_E(a, b, method='CIE 1976') 451.7133019... >>> delta_E(a, b, method='CIE 1994') 83.7792255... >>> delta_E(a, b, method='CIE 1994', textiles=False) ... 83.7792255... >>> delta_E(a, b, method='DIN99') 66.1119282... >>> a = np.array([54.90433134, -0.08450395, -0.06854831]) >>> b = np.array([54.90433134, -0.08442362, -0.06848314]) >>> delta_E(a, b, method='CAM02-UCS') 0.0001034... >>> delta_E(a, b, method='CAM16-LCD') 0.0001034...