colour.hdr_IPT_to_XYZ

colour.hdr_IPT_to_XYZ(IPT_hdr, Y_s=0.2, Y_abs=100, method=u'Fairchild 2011')

Converts from hdr-IPT colourspace to CIE XYZ tristimulus values.

Parameters:

• IPT_hdr (array_like) – hdr-IPT colourspace array.
• Y_s (numeric or array_like) – Relative luminance \(Y_s\) of the surround in domain [0, 1].
• Y_abs (numeric or array_like) – Absolute luminance \(Y_{abs}\) of the scene diffuse white in \(cd/m^2\).
• method (unicode, optional) – {‘Fairchild 2011’, ‘Fairchild 2010’}, Computation method.

Returns:

CIE XYZ tristimulus values.

Return type:

ndarray

References

• [FW10]
• [FC11]

Examples

>>> IPT_hdr = np.array([93.53174734, 1.85641567, -1.32922546])
>>> hdr_IPT_to_XYZ(IPT_hdr)  
array([ 0.9690723...,  1.        ,  1.1217921...])
>>> IPT_hdr = np.array([94.65929175, 0.38041773, -0.26731187])
>>> hdr_IPT_to_XYZ(IPT_hdr, method='Fairchild 2010')
... 
array([ 0.9690723...,  1.        ,  1.1217921...])