colour.models.eotf_inverse_BT2100_HLG#

colour.models.eotf_inverse_BT2100_HLG(F_D: ArrayLike, L_B: float = 0, L_W: float = 1000, gamma: float | None = None, constants: Structure = CONSTANTS_BT2100_HLG, method: Literal['ITU-R BT.2100-1', 'ITU-R BT.2100-2'] | str = 'ITU-R BT.2100-2') NDArrayFloat[source]#

Define Recommendation ITU-R BT.2100 Reference HLG inverse electro-optical transfer function (EOTF).

Parameters:
  • F_D (ArrayLike) – Luminance \(F_D\) of a displayed linear component \({R_D, G_D, B_D}\) or \(Y_D\) or \(I_D\), in \(cd/m^2\).

  • L_B (float) – \(L_B\) is the display luminance for black in \(cd/m^2\).

  • L_W (float) – \(L_W\) is nominal peak luminance of the display in \(cd/m^2\) for achromatic pixels.

  • gamma (float | None) – System gamma value, 1.2 at the nominal display peak luminance of \(1000 cd/m^2\).

  • constants (Structure) – Recommendation ITU-R BT.2100 Reference HLG constants.

  • method (Literal['ITU-R BT.2100-1', 'ITU-R BT.2100-2'] | str) – Computation method.

Returns:

\(E'\) denotes a non-linear colour value \({R', G', B'}\) or \({L', M', S'}\) in HLG space.

Return type:

numpy.ndarray

Notes

Domain

Scale - Reference

Scale - 1

F_D

[0, 1]

[0, 1]

Range

Scale - Reference

Scale - 1

E_p

[0, 1]

[0, 1]

References

[Bor17], [InternationalTUnion17], [InternationalTUnion18]

Examples

>>> eotf_inverse_BT2100_HLG(6.476039825649814)  
0.2121320...
>>> eotf_inverse_BT2100_HLG(6.476039825649814, method="ITU-R BT.2100-1")
... 
0.2121320...
>>> eotf_inverse_BT2100_HLG(7.332197528353875, 0.01)  
0.2121320...