colour.XYZ_to_Jzazbz#

colour.XYZ_to_Jzazbz(XYZ_D65: ArrayLike, constants: Structure = CONSTANTS_JZAZBZ_SAFDAR2017) → NDArrayFloat[source]#

Convert from CIE XYZ tristimulus values to \(J_za_zb_z\) colourspace.

Parameters:

XYZ_D65 (ArrayLike) – CIE XYZ tristimulus values under CIE Standard Illuminant D Series D65.
constants (Structure) – \(J_za_zb_z\) colourspace constants.

Returns:

\(J_za_zb_z\) colourspace array where \(J_z\) is Lightness, \(a_z\) is redness-greenness and \(b_z\) is yellowness-blueness.

Return type:

numpy.ndarray

Warning

The underlying SMPTE ST 2084:2014 transfer function is an absolute transfer function.

Notes

The underlying SMPTE ST 2084:2014 transfer function is an absolute transfer function, thus the domain and range values for the Reference and 1 scales are only indicative that the data is not affected by scale transformations. The effective domain of SMPTE ST 2084:2014 inverse electro-optical transfer function (EOTF) is [0.0001, 10000].

Domain	Scale - Reference	Scale - 1
`XYZ`	`UN`	`UN`

Range	Scale - Reference	Scale - 1
`Jzazbz`	`Jz` : [0, 1] `az` : [-1, 1] `bz` : [-1, 1]	`Jz` : [0, 1] `az` : [-1, 1] `bz` : [-1, 1]

Range

Scale - Reference

Scale - 1

Jzazbz

Jz : [0, 1]

az : [-1, 1]

bz : [-1, 1]

Jz : [0, 1]

az : [-1, 1]

bz : [-1, 1]

References

Examples

>>> XYZ = np.array([0.20654008, 0.12197225, 0.05136952])
>>> XYZ_to_Jzazbz(XYZ)  
array([ 0.0053504...,  0.0092430...,  0.0052600...])