colour.models.eotf_BT2100_HLG

colour.models.eotf_BT2100_HLG(E_p: Domain1, L_B: float = 0, L_W: float = 1000, gamma: float | None = None, constants: Structure | None = None, method: Literal['ITU-R BT.2100-1', 'ITU-R BT.2100-2'] | str = 'ITU-R BT.2100-2') → Range1

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

Parameters:

• E_p (Domain1) – \(E'\) denotes the non-linear signal \(\{R', G', B'\}\).

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

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

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

• constants (Structure | None) – Recommendation ITU-R BT.2100 Reference HLG constants.

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

Returns:

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

Return type:

numpy.ndarray

Notes

Domain	Scale - Reference	Scale - 1
E_p	1	1

Range	Scale - Reference	Scale - 1
F_D	1	1

References

[Bor17], [InternationalTUnion17], [InternationalTUnion18]

Examples

>>> eotf_BT2100_HLG(0.212132034355964)
6.4760398...
>>> eotf_BT2100_HLG(0.212132034355964, method="ITU-R BT.2100-1")
...
6.4760398...
>>> eotf_BT2100_HLG(0.212132034355964, 0.01)
...
7.3321975...