colour.models.XYZ_to_Izazbz#
- colour.models.XYZ_to_Izazbz(XYZ_D65: ArrayLike, constants: Structure | None = None, method: Literal['Safdar 2017', 'Safdar 2021', 'ZCAM'] | str = 'Safdar 2017') NDArrayFloat [source]#
Convert from CIE XYZ tristimulus values to \(I_za_zb_z\) colourspace.
- Parameters:
XYZ_D65 (ArrayLike) – CIE XYZ tristimulus values under CIE Standard Illuminant D Series D65.
constants (Structure | None) – \(J_za_zb_z\) colourspace constants.
method (Literal['Safdar 2017', 'Safdar 2021', 'ZCAM'] | str) – Computation method, Safdar 2021 and ZCAM methods are equivalent.
- Returns:
\(I_za_zb_z\) colourspace array where \(I_z\) is the achromatic response, \(a_z\) is redness-greenness and \(b_z\) is yellowness-blueness.
- Return type:
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
Izazbz
Iz
: [0, 1]az
: [-1, 1]bz
: [-1, 1]Iz
: [0, 1]az
: [-1, 1]bz
: [-1, 1]References
Examples
>>> XYZ = np.array([0.20654008, 0.12197225, 0.05136952]) >>> XYZ_to_Izazbz(XYZ) array([ 0.0120779..., 0.0092430..., 0.0052600...])