text: # -*- coding: utf-8 -*-
  """
  Beta RGB Colourspace
  ====================
  
  Defines the *Beta RGB* colourspace:
  
  -   :attr:`colour.models.BETA_RGB_COLOURSPACE`.
  
  References
  ----------
  -   :cite:`Lindbloom2014a` : Lindbloom, B. (2014). RGB Working Space
      Information. Retrieved April 11, 2014, from
      http://www.brucelindbloom.com/WorkingSpaceInfo.html
  """
  
  from __future__ import division, unicode_literals
  
  import numpy as np
  from functools import partial
  
  from colour.colorimetry import ILLUMINANTS
  from colour.models.rgb import (RGB_Colourspace, gamma_function,
                                 normalised_primary_matrix)
  
  __author__ = 'Colour Developers'
  __copyright__ = 'Copyright (C) 2013-2020 - Colour Developers'
  __license__ = 'New BSD License - https://opensource.org/licenses/BSD-3-Clause'
  __maintainer__ = 'Colour Developers'
  __email__ = 'colour-developers@colour-science.org'
  __status__ = 'Production'
  
  __all__ = [
      'BETA_RGB_PRIMARIES', 'BETA_RGB_WHITEPOINT_NAME', 'BETA_RGB_WHITEPOINT',
      'BETA_RGB_TO_XYZ_MATRIX', 'XYZ_TO_BETA_RGB_MATRIX', 'BETA_RGB_COLOURSPACE'
  ]
  
  BETA_RGB_PRIMARIES = np.array([
      [0.6888, 0.3112],
      [0.1986, 0.7551],
      [0.1265, 0.0352],
  ])
  """
  *Beta RGB* colourspace primaries.
  
  BETA_RGB_PRIMARIES : ndarray, (3, 2)
  """
  
  BETA_RGB_WHITEPOINT_NAME = 'D50'
  """
  *Beta RGB* colourspace whitepoint name.
  
  BETA_RGB_WHITEPOINT_NAME : unicode
  """
  
  BETA_RGB_WHITEPOINT = (ILLUMINANTS['CIE 1931 2 Degree Standard Observer'][
      BETA_RGB_WHITEPOINT_NAME])
  """
  *Beta RGB* colourspace whitepoint.
  
  BETA_RGB_WHITEPOINT : ndarray
  """
  
  BETA_RGB_TO_XYZ_MATRIX = normalised_primary_matrix(BETA_RGB_PRIMARIES,
                                                     BETA_RGB_WHITEPOINT)
  """
  *Beta RGB* colourspace to *CIE XYZ* tristimulus values matrix.
  
  BETA_RGB_TO_XYZ_MATRIX : array_like, (3, 3)
  """
  
  XYZ_TO_BETA_RGB_MATRIX = np.linalg.inv(BETA_RGB_TO_XYZ_MATRIX)
  """
  *CIE XYZ* tristimulus values to *Beta RGB* colourspace matrix.
  
  XYZ_TO_BETA_RGB_MATRIX : array_like, (3, 3)
  """
  
  BETA_RGB_COLOURSPACE = RGB_Colourspace(
      'Beta RGB',
      BETA_RGB_PRIMARIES,
      BETA_RGB_WHITEPOINT,
      BETA_RGB_WHITEPOINT_NAME,
      BETA_RGB_TO_XYZ_MATRIX,
      XYZ_TO_BETA_RGB_MATRIX,
      partial(gamma_function, exponent=1 / 2.2),
      partial(gamma_function, exponent=2.2),
  )
  BETA_RGB_COLOURSPACE.__doc__ = """
  *Beta RGB* colourspace.
  
  References
  ----------
  :cite:`Lindbloom2014a`
  
  BETA_RGB_COLOURSPACE : RGB_Colourspace
  """
  