colour.models.rgb.transfer_functions.arib_std_b67 Module

ARIB STD-B67 (Hybrid Log-Gamma)

Defines ARIB STD-B67 (Hybrid Log-Gamma) opto-electrical transfer function (OETF / OECF) and electro-optical transfer function (EOTF / EOCF):

References

[1]Association of Radio Industries and Businesses. (2015). Essential Parameter Values for the Extended Image Dynamic Range Television (EIDRTV) System for Programme Production. Arib Std-B67. Retrieved from http://www.arib.or.jp/english/html/overview/std-b67.html
colour.models.rgb.transfer_functions.arib_std_b67.ARIBSTDB67_CONSTANTS = {'a': 0.17883277, 'c': 0.55991073, 'b': 0.28466892}

ARIB STD-B67 (Hybrid Log-Gamma) constants.

ARIBSTDB67_CONSTANTS : Structure

colour.models.rgb.transfer_functions.arib_std_b67.oetf_ARIBSTDB67(E, r=0.5)[source]

Defines ARIB STD-B67 (Hybrid Log-Gamma) opto-electrical transfer function (OETF / OECF).

Parameters:
  • E (numeric or array_like) – Voltage normalized by the reference white level and proportional to the implicit light intensity that would be detected with a reference camera color channel R, G, B.
  • r (numeric, optional) – Video level corresponding to reference white level.
Returns:

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

Return type:

numeric or ndarray

Examples

>>> oetf_ARIBSTDB67(0.18)  
0.2121320...
colour.models.rgb.transfer_functions.arib_std_b67.eotf_ARIBSTDB67(E_p, r=0.5)[source]

Defines ARIB STD-B67 (Hybrid Log-Gamma) electro-optical transfer function (EOTF / EOCF).

Parameters:
  • E_p (numeric or array_like) – Non-linear signal \(E'\).
  • r (numeric, optional) – Video level corresponding to reference white level.
Returns:

Voltage \(E\) normalized by the reference white level and proportional to the implicit light intensity that would be detected with a reference camera color channel R, G, B.

Return type:

numeric or ndarray

Warning

ARIB STD-B67 (Hybrid Log-Gamma) doesn’t specify an electro-optical transfer function. This definition is used for symmetry in unit tests and other computations but should not be used as an EOTF.

Examples

>>> eotf_ARIBSTDB67(0.212132034355964)  
0.1799999...