colour.models.rgb.transfer_functions.bt_1886 Module

ITU-R BT.1886

Defines Recommendation ITU-R BT.1886 opto-electrical transfer function (OETF / OECF) and electro-optical transfer function (EOTF / EOCF):

See also

RGB Colourspaces Jupyter Notebook

References

[1]International Telecommunication Union. (2011). Recommendation ITU-R BT.1886 - Reference electro-optical transfer function for flat panel displays used in HDTV studio production BT Series Broadcasting service.
colour.models.rgb.transfer_functions.bt_1886.oetf_BT1886(L, L_B=64, L_W=940)[source]

Defines Recommendation ITU-R BT.1886 opto-electrical transfer function (OETF / OECF).

Parameters:
  • L (numeric or array_like) – Screen luminance in \(cd/m^2\).
  • L_B (numeric, optional) – Screen luminance for black.
  • L_W (numeric, optional) – Screen luminance for white.
Returns:

Input video signal level (normalized, black at \(V = 0\), to white at \(V = 1\).
Return type:

numeric or ndarray

Warning

Recommendation ITU-R BT.1886 doesn’t specify an opto-electrical transfer function. This definition is used for symmetry in unit tests and other computations but should not be used as an OETF.

Examples

>>> oetf_BT1886(277.98159179331145)  
0.4090077...
colour.models.rgb.transfer_functions.bt_1886.eotf_BT1886(V, L_B=64, L_W=940)[source]

Defines Recommendation ITU-R BT.1886 electro-optical transfer function (EOTF / EOCF).

Parameters:
  • V (numeric or array_like) – Input video signal level (normalized, black at \(V = 0\), to white at \(V = 1\). For content mastered per Recommendation ITU-R BT.709, 10-bit digital code values \(D\) map into values of \(V\) per the following equation: \(V = (D–64)/876\)
  • L_B (numeric, optional) – Screen luminance for black.
  • L_W (numeric, optional) – Screen luminance for white.
Returns:

Screen luminance in \(cd/m^2\).
Return type:

numeric or ndarray

Examples

>>> eotf_BT1886(0.409007728864150)  
277.9815917...