colour.models.oetf_inverse_H273_IEC61966_2#

colour.models.oetf_inverse_H273_IEC61966_2(V: Annotated[_Buffer | _SupportsArray[dtype[Any]] | _NestedSequence[_SupportsArray[dtype[Any]]] | complex | bytes | str | _NestedSequence[complex | bytes | str], 1]) → Annotated[ndarray[tuple[Any, ...], dtype[float16 | float32 | float64]], 1][source]#

Apply the Recommendation ITU-T H.273 inverse opto-electronic transfer function (OETF) for the IEC 61966-2 family of transfer functions (2-1 sRGB, 2-1 sYCC, 2-4 xvYCC).

Parameters:

V (Annotated[_Buffer | _SupportsArray[dtype[Any]] | _NestedSequence[_SupportsArray[dtype[Any]]] | complex | bytes | str | _NestedSequence[complex | bytes | str], 1]) – Electrical signal \(V\).

Returns:

Scene luminance \(L_c\).

Return type:

numpy.ndarray

Notes

Usage in [InternationalTUnion21] is specified as follows:

  • For IEC 61966-2-1 sRGB (MatrixCoefficients=0), the function is only defined for \(L_c\) in [0-1] range.

  • For IEC 61966-2-1 sYCC (MatrixCoefficients=5) and IEC 61966-2-4 xvYCC, the function is defined for any real-valued \(L_c\).

Domain

Scale - Reference

Scale - 1

V

1

1

Range

Scale - Reference

Scale - 1

L_c

1

1

References

Examples

>>> oetf_inverse_H273_IEC61966_2(0.461356129500)
np.float64(0.1799999999...)
>>> oetf_inverse_H273_IEC61966_2(-0.461356129500)
np.float64(-0.1799999999...)