colour.models.common Module¶

Common Colour Models Utilities¶

Defines various colour models common utilities.

colour.models.common.XYZ_to_sRGB(XYZ, illuminant=(0.31271, 0.32902), chromatic_adaptation_transform=u'CAT02', transfer_function=True)[source]¶

Converts from CIE XYZ tristimulus values to sRGB colourspace.

Parameters:	XYZ (array_like) – CIE XYZ tristimulus values. illuminant (array_like, optional) – Source illuminant chromaticity coordinates. chromatic_adaptation_transform (unicode, optional) – {‘CAT02’, ‘XYZ Scaling’, ‘Von Kries’, ‘Bradford’, ‘Sharp’, ‘Fairchild, ‘CMCCAT97’, ‘CMCCAT2000’, ‘CAT02_BRILL_CAT’, ‘Bianco’, ‘Bianco PC’}, Chromatic adaptation transform. transfer_function (bool, optional) – Apply sRGB transfer function.
Returns:	sRGB colour array.
Return type:	ndarray

Notes

• Input CIE XYZ tristimulus values are in domain [0, 1].

Examples

>>> import numpy as np
>>> XYZ = np.array([0.07049534, 0.10080000, 0.09558313])
>>> XYZ_to_sRGB(XYZ)  
array([ 0.1750135...,  0.3881879...,  0.3216195...])

colour.models.common.sRGB_to_XYZ(RGB, illuminant=(0.31271, 0.32902), chromatic_adaptation_method=u'CAT02', inverse_transfer_function=True)[source]¶

Converts from sRGB colourspace to CIE XYZ tristimulus values.

Parameters:	RGB (array_like) – sRGB colourspace array. illuminant (array_like, optional) – Source illuminant chromaticity coordinates. chromatic_adaptation_method (unicode, optional) – {‘CAT02’, ‘XYZ Scaling’, ‘Von Kries’, ‘Bradford’, ‘Sharp’, ‘Fairchild, ‘CMCCAT97’, ‘CMCCAT2000’, ‘CAT02_BRILL_CAT’, ‘Bianco’, ‘Bianco PC’}, Chromatic adaptation method. inverse_transfer_function (bool, optional) – Apply sRGB inverse transfer function.
Returns:	CIE XYZ tristimulus values.
Return type:	ndarray

Notes

• Input RGB colourspace array is in domain [0, 1].

Examples

>>> import numpy as np
>>> RGB = np.array([0.17501358, 0.38818795, 0.32161955])
>>> sRGB_to_XYZ(RGB)  
array([ 0.0704953...,  0.1008    ,  0.0955831...])