Colour - RGB Colourspace Definition

colour_rgb_colourspace_definition.py

import numpy as np

import colour

# Manual NPM Derivation
primaries=np.array([[0.1, 0.2],
                    [0.3, 0.4],
                    [0.5, 0.6]])
whitepoint=np.array([0.5, 0.5])
npm = colour.normalised_primary_matrix(
    primaries, whitepoint)
RGB_COLOURSPACE_A = colour.RGB_Colourspace(
    'RGB Colourspace A',
    primaries=primaries,
    whitepoint=whitepoint,
    RGB_to_XYZ_matrix=npm,
    XYZ_to_RGB_matrix=np.linalg.inv(npm))

print(RGB_COLOURSPACE_A.RGB_to_XYZ_matrix)
# [[  1.32458813e+14  -7.94752875e+14   6.62294063e+14]
#  [  2.64917625e+14  -1.05967050e+15   7.94752875e+14]
#  [  9.27211688e+14  -7.94752875e+14  -1.32458813e+14]]

# Automatic NPM Derivation
RGB_COLOURSPACE_B = colour.RGB_Colourspace(
    'RGB Colourspace B',
    primaries=np.array([[0.1, 0.2],
                        [0.3, 0.4],
                        [0.5, 0.6]]),
    whitepoint=np.array([0.5, 0.5]),
    use_derived_RGB_to_XYZ_matrix=True,
    use_derived_XYZ_to_RGB_matrix=True)

print(RGB_COLOURSPACE_B.RGB_to_XYZ_matrix)
# [[  1.32458813e+14  -7.94752875e+14   6.62294063e+14]
#  [  2.64917625e+14  -1.05967050e+15   7.94752875e+14]
#  [  9.27211688e+14  -7.94752875e+14  -1.32458813e+14]]

# If you need to plot them, etc... you need to make them available to the API this way:
colour.RGB_COLOURSPACES['RGB Colourspace A'] = RGB_COLOURSPACE_A
colour.RGB_COLOURSPACES['RGB Colourspace B'] = RGB_COLOURSPACE_B