colour.models.cie_ucs Module

CIE UCS Colourspace

Defines the CIE UCS colourspace transformations:

References

[1]Wikipedia. (n.d.). CIE 1960 color space. Retrieved February 24, 2014, from http://en.wikipedia.org/wiki/CIE_1960_color_space
[2]Wikipedia. (n.d.). Relation to CIE XYZ. Retrieved February 24, 2014, from http://en.wikipedia.org/wiki/CIE_1960_color_space#Relation_to_CIE_XYZ
colour.models.cie_ucs.XYZ_to_UCS(XYZ)[source]

Converts from CIE XYZ tristimulus values to CIE UCS colourspace.

Parameters:XYZ (array_like) – CIE XYZ tristimulus values.
Returns:CIE UCS colourspace array.
Return type:ndarray

Notes

  • Input CIE XYZ tristimulus values are in domain [0, 1].
  • Output CIE UCS colourspace array is in domain [0, 1].

Examples

>>> import numpy as np
>>> XYZ = np.array([0.07049534, 0.10080000, 0.09558313])
>>> XYZ_to_UCS(XYZ)  
array([ 0.0469968...,  0.1008    ,  0.1637439...])
colour.models.cie_ucs.UCS_to_XYZ(UVW)[source]

Converts from CIE UCS colourspace to CIE XYZ tristimulus values.

Parameters:UVW (array_like) – CIE UCS colourspace array.
Returns:CIE XYZ tristimulus values.
Return type:ndarray

Notes

  • Input CIE UCS colourspace array is in domain [0, 1].
  • Output CIE XYZ tristimulus values are in domain [0, 1].

Examples

>>> import numpy as np
>>> UVW = np.array([0.04699689, 0.10080000, 0.16374390])
>>> UCS_to_XYZ(UVW)  
array([ 0.0704953...,  0.1008    ,  0.0955831...])
colour.models.cie_ucs.UCS_to_uv(UVW)[source]

Returns the uv chromaticity coordinates from given CIE UCS colourspace array.

Parameters:UVW (array_like) – CIE UCS colourspace array.
Returns:uv chromaticity coordinates.
Return type:ndarray

Notes

  • Input CIE UCS colourspace array is in domain [0, 1].
  • Output uv chromaticity coordinates are in domain [0, 1].

Examples

>>> import numpy as np
>>> UCS = np.array([0.04699689, 0.10080000, 0.16374390])
>>> UCS_to_uv(UCS)  
array([ 0.1508530...,  0.3235531...])
colour.models.cie_ucs.UCS_uv_to_xy(uv)[source]

Returns the xy chromaticity coordinates from given CIE UCS colourspace uv chromaticity coordinates.

Parameters:uv (array_like) – CIE UCS uv chromaticity coordinates.
Returns:xy chromaticity coordinates.
Return type:ndarray

Notes

  • Input uv chromaticity coordinates are in domain [0, 1].
  • Output xy chromaticity coordinates are in domain [0, 1].

Examples

>>> import numpy as np
>>> uv = np.array([0.15085308732766581, 0.3235531372954405])
>>> UCS_uv_to_xy(uv)  
array([ 0.2641477...,  0.3777000...])