colour.colorimetry.lefs Module¶
Luminous Efficiency Functions Spectral Power Distributions¶
Defines luminous efficiency functions computation related objects.
See also
Luminous Efficiency Functions IPython Notebook colour.colorimetry.dataset.lefs, colour.colorimetry.spectrum.SpectralPowerDistribution
References
[1] | Wikipedia. (n.d.). Mesopic weighting function. Retrieved June 20, 2014, from http://en.wikipedia.org/wiki/Mesopic_vision#Mesopic_weighting_function |
-
colour.colorimetry.lefs.
mesopic_weighting_function
(wavelength, Lp, source=u'Blue Heavy', method=u'MOVE', photopic_lef=<colour.colorimetry.spectrum.SpectralPowerDistribution object>, scotopic_lef=<colour.colorimetry.spectrum.SpectralPowerDistribution object>)[source]¶ Calculates the mesopic weighting function factor at given wavelength \(\lambda\) using the photopic luminance \(L_p\).
Parameters: - wavelength (numeric or array_like) – Wavelength \(\lambda\) to calculate the mesopic weighting function factor.
- Lp (numeric) – Photopic luminance \(L_p\).
- source (unicode, optional) – {‘Blue Heavy’, ‘Red Heavy’}, Light source colour temperature.
- method (unicode, optional) – {‘MOVE’, ‘LRC’}, Method to calculate the weighting factor.
- photopic_lef (SpectralPowerDistribution, optional) – \(V(\lambda)\) photopic luminous efficiency function.
- scotopic_lef (SpectralPowerDistribution, optional) – \(V^\prime(\lambda)\) scotopic luminous efficiency function.
Returns: Mesopic weighting function factor.
Return type: numeric or ndarray
Examples
>>> mesopic_weighting_function(500, 0.2) 0.7052200...
-
colour.colorimetry.lefs.
mesopic_luminous_efficiency_function
(Lp, source=u'Blue Heavy', method=u'MOVE', photopic_lef=<colour.colorimetry.spectrum.SpectralPowerDistribution object>, scotopic_lef=<colour.colorimetry.spectrum.SpectralPowerDistribution object>)[source]¶ Returns the mesopic luminous efficiency function \(V_m(\lambda)\) for given photopic luminance \(L_p\).
Parameters: - Lp (numeric) – Photopic luminance \(L_p\).
- source (unicode, optional) – {‘Blue Heavy’, ‘Red Heavy’}, Light source colour temperature.
- method (unicode, optional) – {‘MOVE’, ‘LRC’}, Method to calculate the weighting factor.
- photopic_lef (SpectralPowerDistribution, optional) – \(V(\lambda)\) photopic luminous efficiency function.
- scotopic_lef (SpectralPowerDistribution, optional) – \(V^\prime(\lambda)\) scotopic luminous efficiency function.
Returns: Mesopic luminous efficiency function \(V_m(\lambda)\).
Return type: Examples
>>> mesopic_luminous_efficiency_function(0.2) <colour.colorimetry.spectrum.SpectralPowerDistribution object at 0x...>