# Colour Difference¶

## Delta E¶

colour

 delta_E(a, b[, method]) Returns the difference $$\Delta E_{ab}$$ between two given CIE L*a*b* or $$J'a'b'$$ colourspace arrays using given method. DELTA_E_METHODS Supported $$\Delta E_{ab}$$ computation methods.

## CIE 1976¶

colour.difference

 JND_CIE1976 Just Noticeable Difference (JND) according to CIE 1976 colour difference formula, i.e. Euclidean distance in CIE L*a*b* colourspace. delta_E_CIE1976(Lab_1, Lab_2) Returns the difference $$\Delta E_{76}$$ between two given CIE L*a*b* colourspace arrays using CIE 1976 recommendation.

## CIE 1994¶

colour.difference

 delta_E_CIE1994(Lab_1, Lab_2[, textiles]) Returns the difference $$\Delta E_{94}$$ between two given CIE L*a*b* colourspace arrays using CIE 1994 recommendation.

## CIE 2000¶

colour.difference

 delta_E_CIE2000(Lab_1, Lab_2[, textiles]) Returns the difference $$\Delta E_{00}$$ between two given CIE L*a*b* colourspace arrays using CIE 2000 recommendation.

## CMC¶

colour.difference

 delta_E_CMC(Lab_1, Lab_2[, l, c]) Returns the difference $$\Delta E_{CMC}$$ between two given CIE L*a*b* colourspace arrays using Colour Measurement Committee recommendation.

## Luo, Cui and Li (2006)¶

colour.difference

 delta_E_CAM02LCD(Jpapbp_1, Jpapbp_2) Returns the difference $$\Delta E'$$ between two given *Luo et al. delta_E_CAM02SCD(Jpapbp_1, Jpapbp_2) Returns the difference $$\Delta E'$$ between two given *Luo et al. delta_E_CAM02UCS(Jpapbp_1, Jpapbp_2) Returns the difference $$\Delta E'$$ between two given *Luo et al.

## Li, Li, Wang, Zu, Luo, Cui, Melgosa, Brill and Pointer (2017)¶

colour.difference

 delta_E_CAM16LCD(Jpapbp_1, Jpapbp_2) Returns the difference $$\Delta E'$$ between two given *Li et al. delta_E_CAM16SCD(Jpapbp_1, Jpapbp_2) Returns the difference $$\Delta E'$$ between two given *Li et al. delta_E_CAM16UCS(Jpapbp_1, Jpapbp_2) Returns the difference $$\Delta E'$$ between two given *Li et al.

## DIN99¶

colour.difference

 delta_E_DIN99(Lab_1, Lab_2[, textiles]) Returns the difference $$\Delta E_{DIN99}$$ between two given CIE L*a*b* colourspace arrays using DIN99 formula.