colour.XYZ_to_RGB

colour.XYZ_to_RGB(XYZ, illuminant_XYZ, illuminant_RGB, XYZ_to_RGB_matrix, chromatic_adaptation_transform=u'CAT02', encoding_cctf=None)[source]

Converts from CIE XYZ tristimulus values to given RGB colourspace.

Parameters:
  • XYZ (array_like) – CIE XYZ tristimulus values.
  • illuminant_XYZ (array_like) – CIE XYZ tristimulus values illuminant xy chromaticity coordinates or CIE xyY colourspace array.
  • illuminant_RGB (array_like) – RGB colourspace illuminant xy chromaticity coordinates or CIE xyY colourspace array.
  • XYZ_to_RGB_matrix (array_like) – Normalised primary matrix.
  • chromatic_adaptation_transform (unicode, optional) – {‘CAT02’, ‘XYZ Scaling’, ‘Von Kries’, ‘Bradford’, ‘Sharp’, ‘Fairchild’, ‘CMCCAT97’, ‘CMCCAT2000’, ‘CAT02_BRILL_CAT’, ‘Bianco’, ‘Bianco PC’}, Chromatic adaptation transform.
  • encoding_cctf (object, optional) – Encoding colour component transfer function (Encoding CCTF) or opto-electronic transfer function (OETF / OECF).
Returns:

RGB colourspace array.
Return type:

ndarray

Notes

  • Input CIE XYZ tristimulus values are in domain [0, 1].
  • Input illuminant_XYZ xy chromaticity coordinates or CIE xyY colourspace array are in domain [0, \(\infty\)].
  • Input illuminant_RGB xy chromaticity coordinates or CIE xyY colourspace array are in domain [0, \(\infty\)].
  • Output RGB colourspace array is in range [0, 1].

Examples

>>> XYZ = np.array([0.07049534, 0.10080000, 0.09558313])
>>> illuminant_XYZ = np.array([0.34570, 0.35850])
>>> illuminant_RGB = np.array([0.31270, 0.32900])
>>> chromatic_adaptation_transform = 'Bradford'
>>> XYZ_to_RGB_matrix = np.array(
...     [[3.24062548, -1.53720797, -0.49862860],
...      [-0.96893071, 1.87575606, 0.04151752],
...      [0.05571012, -0.20402105, 1.05699594]]
... )
>>> XYZ_to_RGB(XYZ, illuminant_XYZ, illuminant_RGB, XYZ_to_RGB_matrix,
...            chromatic_adaptation_transform)  
array([ 0.0110015...,  0.1273504...,  0.1163271...])