colour.models.oetf_BT2020

colour.models.oetf_BT2020(E, is_12_bits_system=False, constants={'alpha': <function <lambda>>, 'beta': <function <lambda>>})[source]

Defines Recommendation ITU-R BT.2020 opto-electrical transfer function (OETF / OECF).

Parameters
  • E (numeric or array_like) – 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, optional) – BT.709 alpha and beta constants are used if system is not 12-bit.

  • constants (Structure, optional) – Recommendation ITU-R BT.2020 constants.

Returns

Resulting non-linear signal \(E'\).

Return type

numeric or ndarray

Notes

Domain

Scale - Reference

Scale - 1

E

[0, 1]

[0, 1]

Range

Scale - Reference

Scale - 1

E_p

[0, 1]

[0, 1]

References

[InternationalTUnion15a]

Examples

>>> oetf_BT2020(0.18)  
0.4090077...