colour.models.oetf_BT2020

colour.models.oetf_BT2020(E: Annotated[_Buffer | _SupportsArray[dtype[Any]] | _NestedSequence[_SupportsArray[dtype[Any]]] | complex | bytes | str | _NestedSequence[complex | bytes | str], 1], is_12_bits_system: bool = False, constants: Structure | None = None) → Annotated[ndarray[tuple[Any, ...], dtype[float16 | float32 | float64]], 1]

Apply the Recommendation ITU-R BT.2020 opto-electronic transfer function (OETF).

Parameters:

• E (Annotated[_Buffer | _SupportsArray[dtype[Any]] | _NestedSequence[_SupportsArray[dtype[Any]]] | complex | bytes | str | _NestedSequence[complex | bytes | str], 1]) – Voltage \(E\) normalised by the reference white level and proportional to the implicit light intensity that would be detected with a reference camera colour channel R, G, B.

• is_12_bits_system (bool) – BT.709 alpha and beta constants are used if system is not 12-bit.

• constants (Structure | None) – Recommendation ITU-R BT.2020 constants.

Returns:

Non-linear signal \(E'\).

Return type:

numpy.ndarray

Notes

Domain	Scale - Reference	Scale - 1
E	1	1

Range	Scale - Reference	Scale - 1
E_p	1	1

References

[InternationalTUnion15a]

Examples

>>> oetf_BT2020(0.18)
np.float64(0.4090077...)