colour.hdr_IPT_to_XYZ

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

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.
  • 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

Notes

Domain Scale - Reference Scale - 1
IPT_hdr

I_hdr : [0, 100]

P_hdr : [-100, 100]

T_hdr : [-100, 100]

I_hdr : [0, 1]

P_hdr : [-1, 1]

T_hdr : [-1, 1]

Y_s [0, 1] [0, 1]
Range Scale - Reference Scale - 1
XYZ [0, 1] [0, 1]

References

[Fairchild2010], [Fairchild2011]

Examples

>>> IPT_hdr = np.array([48.39376346, 42.44990202, 22.01954033])
>>> hdr_IPT_to_XYZ(IPT_hdr)  # doctest: +ELLIPSIS
array([ 0.2065400...,  0.1219722...,  0.0513695...])
>>> IPT_hdr = np.array([30.02873147, 83.93845061, 34.90287382])
>>> hdr_IPT_to_XYZ(IPT_hdr, method='Fairchild 2010')
... # doctest: +ELLIPSIS
array([ 0.2065400...,  0.1219722...,  0.0513695...])