Colour is a Python colour science package implementing a comprehensive number of colour theory transformations and algorithms.
It is open source and freely available under the New BSD License terms.
Colour features a rich dataset and collection of objects, please see the features page for more information.
Anaconda from Continuum Analytics is the Python distribution we use to develop Colour: it ships all the scientific dependencies we require and is easily deployed cross-platform:
$ conda create -y -n python-colour
$ source activate python-colour
$ conda install -y -c conda-forge colour-scienceColour can be easily installed from the Python Package Index by issuing this command in a shell:
$ pip install colour-scienceThe detailed installation procedure is described in the Installation Guide.
The two main references for Colour usage are the Colour Manual and the Jupyter Notebooks with detailed historical and theoretical context and images:
Most of the objects are available from the colour namespace:
>>> import colour>>> XYZ = [0.07049534, 0.10080000, 0.09558313]
>>> A = colour.ILLUMINANTS['CIE 1931 2 Degree Standard Observer']['A']
>>> D65 = colour.ILLUMINANTS['CIE 1931 2 Degree Standard Observer']['D65']
>>> colour.chromatic_adaptation(
... XYZ, colour.xy_to_XYZ(A), colour.xy_to_XYZ(D65))
array([ 0.08398225, 0.11413379, 0.28629643])
>>> sorted(colour.CHROMATIC_ADAPTATION_METHODS.keys())
['CIE 1994', 'CMCCAT2000', 'Fairchild 1990', 'Von Kries']>>> y = [5.9200, 9.3700, 10.8135, 4.5100, 69.5900, 27.8007, 86.0500]
>>> x = range(len(y))
>>> colour.KernelInterpolator(x, y)([0.25, 0.75, 5.50])
array([ 6.18062083, 8.08238488, 57.85783403])>>> y = [5.9200, 9.3700, 10.8135, 4.5100, 69.5900, 27.8007, 86.0500]
>>> x = range(len(y))
>>> colour.SpragueInterpolator(x, y)([0.25, 0.75, 5.50])
array([ 6.72951612, 7.81406251, 43.77379185])>>> colour.spectral_to_XYZ(colour.LIGHT_SOURCES_SPDS['Neodimium Incandescent'])
array([ 36.94726204, 32.62076174, 13.0143849 ])
>>> sorted(colour.SPECTRAL_TO_XYZ_METHODS.keys())
[u'ASTM E308-15', u'Integration', u'astm2015']>>> msa = np.array([
... [[0.01367208, 0.09127947, 0.01524376, 0.02810712, 0.19176012, 0.04299992],
... [0.00959792, 0.25822842, 0.41388571, 0.22275120, 0.00407416, 0.37439537],
... [0.01791409, 0.29707789, 0.56295109, 0.23752193, 0.00236515, 0.58190280]],
... [[0.01492332, 0.10421912, 0.02240025, 0.03735409, 0.57663846, 0.32416266],
... [0.04180972, 0.26402685, 0.03572137, 0.00413520, 0.41808194, 0.24696727],
... [0.00628672, 0.11454948, 0.02198825, 0.39906919, 0.63640803, 0.01139849]],
... [[0.04325933, 0.26825359, 0.23732357, 0.05175860, 0.01181048, 0.08233768],
... [0.02484169, 0.12027161, 0.00541695, 0.00654612, 0.18603799, 0.36247808],
... [0.03102159, 0.16815442, 0.37186235, 0.08610666, 0.00413520, 0.78492409]],
... [[0.11682307, 0.78883040, 0.74468607, 0.83375293, 0.90571451, 0.70054168],
... [0.06321812, 0.41898224, 0.15190357, 0.24591440, 0.55301750, 0.00657664],
... [0.00305180, 0.11288624, 0.11357290, 0.12924391, 0.00195315, 0.21771573]],
... ])
>>> colour.multi_spectral_to_XYZ(msa, colour.SpectralShape(400, 700, 60),
... cmfs, illuminant))
[[[ 9.73192501 5.02105851 3.22790699]
[ 16.08032168 24.47303359 10.28681006]
[ 17.73513774 29.61865582 12.10713449]]
[[ 25.69298792 11.72611193 3.70187275]
[ 18.51208526 8.03720984 9.30361825]
[ 48.55945054 32.30885571 4.09223401]]
[[ 5.7743232 10.10692925 10.08461311]
[ 8.81306527 3.65394599 4.20783881]
[ 8.06007398 15.87077693 7.02551086]]
[[ 90.88877129 81.82966846 29.86765971]
[ 38.64801062 26.70860262 15.08396538]
[ 8.77151115 10.56330761 4.28940206]]]
>>> sorted(colour.MULTI_SPECTRAL_TO_XYZ_METHODS.keys())
[u'Integration']>>> colour.blackbody_spd(5000)
SpectralPowerDistribution([[ 3.60000000e+02, 6.65427827e+12],
[ 3.61000000e+02, 6.70960528e+12],
[ 3.62000000e+02, 6.76482512e+12],
...
[ 7.78000000e+02, 1.06068004e+13],
[ 7.79000000e+02, 1.05903327e+13],
[ 7.80000000e+02, 1.05738520e+13]],
interpolator=SpragueInterpolator,
interpolator_args={},
extrapolator=Extrapolator,
extrapolator_args={u'right': None, u'method': u'Constant', u'left': None})>>> xy = [0.26415, 0.37770]
>>> xy_n = [0.31270, 0.32900]
>>> colour.dominant_wavelength(xy, xy_n)
(array(504.0),
array([ 0.00369694, 0.63895775]),
array([ 0.00369694, 0.63895775]))>>> colour.lightness(10.08)
24.902290269546651
>>> sorted(colour.LIGHTNESS_METHODS.keys())
[u'CIE 1976',
u'Fairchild 2010',
u'Fairchild 2011',
u'Glasser 1958',
u'Lstar1976',
u'Wyszecki 1963']>>> colour.luminance(37.98562910)
10.080000001314646
>>> sorted(colour.LUMINANCE_METHODS.keys())
[u'ASTM D1535-08',
u'CIE 1976',
u'Fairchild 2010',
u'Fairchild 2011',
u'Newhall 1943',
u'astm2008',
u'cie1976']>>> colour.whiteness(xy=[0.3167, 0.3334], Y=100, xy_n=[0.3139, 0.3311])
array([ 93.85 , -1.305])
>>> sorted(colour.WHITENESS_METHODS.keys())
[u'ASTM E313',
u'Berger 1959',
u'CIE 2004',
u'Ganz 1979',
u'Stensby 1968',
u'Taube 1960',
u'cie2004']>>> XYZ = [95.00000000, 100.00000000, 105.00000000]
>>> colour.yellowness(XYZ)
11.065000000000003
>>> sorted(colour.YELLOWNESS_METHODS.keys())
[u'ASTM D1925', u'ASTM E313']>>> spd = colour.LIGHT_SOURCES_SPDS['Neodimium Incandescent']
>>> colour.luminous_flux(spd)
3807.655527367202>>> spd = colour.LIGHT_SOURCES_SPDS['Neodimium Incandescent']
>>> colour.luminous_efficiency(spd)
0.19943935624521045>>> spd = colour.LIGHT_SOURCES_SPDS['Neodimium Incandescent']
>>> colour.luminous_efficacy(spd)
136.21708031547874>>> colour.XYZ_to_xyY([0.07049534, 0.10080000, 0.09558313])
array([ 0.26414772, 0.37770001, 0.1008 ])>>> colour.XYZ_to_Lab([0.07049534, 0.10080000, 0.09558313])
array([ 37.9856291 , -23.62907688, -4.41746615])>>> colour.XYZ_to_Luv([0.07049534, 0.10080000, 0.09558313])
array([ 37.9856291 , -28.80219593, -1.35800706])>>> colour.XYZ_to_UCS([0.07049534, 0.10080000, 0.09558313])
array([ 0.04699689, 0.1008 , 0.1637439 ])>>> colour.XYZ_to_UVW([7.04953400, 10.08000000, 9.55831300])
array([-28.05797333, -0.88194493, 37.00411491])>>> colour.XYZ_to_Hunter_Lab([7.049534, 10.080000, 9.558313])
array([ 31.74901573, -15.11462629, -2.78660758])>>> colour.XYZ_to_Hunter_Rdab([7.049534, 10.080000, 9.558313])
array([ 10.08 , -18.67653764, -3.44329925])>>> XYZ = np.array([19.01, 20.00, 21.78])
>>> XYZ_w = np.array([95.05, 100.00, 108.88])
>>> L_A = 318.31
>>> Y_b = 20.0
>>> surround = colour.CIECAM02_VIEWING_CONDITIONS['Average']
>>> specification = colour.XYZ_to_CIECAM02(
XYZ, XYZ_w, L_A, Y_b, surround)
>>> JMh = (specification.J, specification.M, specification.h)
>>> colour.JMh_CIECAM02_to_CAM02UCS(JMh)
array([ 54.90433134, -0.08442362, -0.06848314])>>> XYZ = np.array([19.01, 20.00, 21.78])
>>> XYZ_w = np.array([95.05, 100.00, 108.88])
>>> L_A = 318.31
>>> Y_b = 20.0
>>> surround = colour.CAM16_VIEWING_CONDITIONS['Average']
>>> specification = colour.XYZ_to_CAM16(
XYZ, XYZ_w, L_A, Y_b, surround)
>>> JMh = (specification.J, specification.M, specification.h)
>>> colour.JMh_CAM16_to_CAM16UCS(JMh)
array([ 54.90445024, -0.08562125, -0.0646796 ])>>> colour.XYZ_to_IPT([0.07049534, 0.10080000, 0.09558313])
array([ 0.36571124, -0.11114798, 0.01594746])>>> colour.XYZ_to_hdr_CIELab([0.07049534, 0.10080000, 0.09558313])
array([ 24.90206646, -46.83127607, -10.14274843])>>> colour.XYZ_to_hdr_IPT([0.07049534, 0.10080000, 0.09558313])
array([ 25.18261761, -22.62111297, 3.18511729])>>> colour.XYZ_to_OSA_UCS([7.04953400, 10.08000000, 9.55831300])
array([-4.4900683 , 0.70305936, 3.03463664])>>> XYZ = [0.07049534, 0.10080000, 0.09558313]
>>> illuminant_XYZ = [0.34570, 0.35850]
>>> illuminant_RGB = [0.31270, 0.32900]
>>> chromatic_adaptation_transform = 'Bradford'
>>> XYZ_to_RGB_matrix = [
[3.24062548, -1.53720797, -0.49862860],
[-0.96893071, 1.87575606, 0.04151752],
[0.05571012, -0.20402105, 1.05699594]]
>>> colour.XYZ_to_RGB(
XYZ,
illuminant_XYZ,
illuminant_RGB,
XYZ_to_RGB_matrix,
chromatic_adaptation_transform)
array([ 0.01100154, 0.12735048, 0.11632713])>>> p = [0.73470, 0.26530, 0.00000, 1.00000, 0.00010, -0.07700]
>>> w = [0.32168, 0.33767]
>>> colour.normalised_primary_matrix(p, w)
array([[ 9.52552396e-01, 0.00000000e+00, 9.36786317e-05],
[ 3.43966450e-01, 7.28166097e-01, -7.21325464e-02],
[ 0.00000000e+00, 0.00000000e+00, 1.00882518e+00]])>>> colour.RGB_to_YCbCr([1.0, 1.0, 1.0])
array([ 0.92156863, 0.50196078, 0.50196078])>>> colour.RGB_to_YCoCg([0.75, 0.75, 0.0])
array([ 0.5625, 0.375 , 0.1875])>>> colour.RGB_to_ICTCP([0.35181454, 0.26934757, 0.21288023])
array([ 0.09554079, -0.00890639, 0.01389286])>>> colour.XYZ_to_JzAzBz(XYZ)
array([ 0.00357804, -0.00295507, 0.00038998])>>> colour.RGB_to_HSV([0.49019608, 0.98039216, 0.25098039])
array([ 0.27867383, 0.744 , 0.98039216])>>> colour.RGB_to_Prismatic([0.25, 0.50, 0.75])
array([ 0.75 , 0.16666667, 0.33333333, 0.5 ])>>> sorted(colour.RGB_COLOURSPACES.keys())
[u'ACES2065-1',
u'ACEScc',
u'ACEScct',
u'ACEScg',
u'ACESproxy',
u'ALEXA Wide Gamut',
u'Adobe RGB (1998)',
u'Adobe Wide Gamut RGB',
u'Apple RGB',
u'Best RGB',
u'Beta RGB',
u'CIE RGB',
u'Cinema Gamut',
u'ColorMatch RGB',
u'DCI-P3',
u'DCI-P3+',
u'DRAGONcolor',
u'DRAGONcolor2',
u'Don RGB 4',
u'ECI RGB v2',
u'ERIMM RGB',
u'Ekta Space PS 5',
u'ITU-R BT.2020',
u'ITU-R BT.470 - 525',
u'ITU-R BT.470 - 625',
u'ITU-R BT.709',
u'Max RGB',
u'NTSC',
u'Pal/Secam',
u'ProPhoto RGB',
u'Protune Native',
u'REDWideGamutRGB',
u'REDcolor',
u'REDcolor2',
u'REDcolor3',
u'REDcolor4',
u'RIMM RGB',
u'ROMM RGB',
u'Russell RGB',
u'S-Gamut',
u'S-Gamut3',
u'S-Gamut3.Cine',
u'SMPTE 240M',
u'V-Gamut',
u'Xtreme RGB',
'aces',
'adobe1998',
'prophoto',
u'sRGB']>>> sorted(colour.OETFS.keys())
['ARIB STD-B67',
'DCI-P3',
'DICOM GSDF',
'ITU-R BT.2020',
'ITU-R BT.2100 HLG',
'ITU-R BT.2100 PQ',
'ITU-R BT.601',
'ITU-R BT.709',
'ProPhoto RGB',
'RIMM RGB',
'ROMM RGB',
'SMPTE 240M',
'ST 2084',
'sRGB']>>> sorted(colour.EOTFS.keys())
['DCI-P3',
'DICOM GSDF',
'ITU-R BT.1886',
'ITU-R BT.2020',
'ITU-R BT.2100 HLG',
'ITU-R BT.2100 PQ',
'ProPhoto RGB',
'RIMM RGB',
'ROMM RGB',
'SMPTE 240M',
'ST 2084']>>> sorted(colour.OOTFS.keys())
['ITU-R BT.2100 HLG', 'ITU-R BT.2100 PQ']>>> sorted(colour.LOG_ENCODING_CURVES.keys())
['ACEScc',
'ACEScct',
'ACESproxy',
'ALEXA Log C',
'Canon Log',
'Canon Log 2',
'Canon Log 3',
'Cineon',
'ERIMM RGB',
'Log3G10',
'Log3G12',
'PLog',
'Panalog',
'Protune',
'REDLog',
'REDLogFilm',
'S-Log',
'S-Log2',
'S-Log3',
'V-Log',
'ViperLog']>>> XYZ = [0.07049534, 0.10080000, 0.09558313]
>>> XYZ_w = [1.09846607, 1.00000000, 0.35582280]
>>> XYZ_wr = [0.95042855, 1.00000000, 1.08890037]
>>> colour.chromatic_adaptation_VonKries(XYZ, XYZ_w, XYZ_wr)
array([ 0.08397461, 0.11413219, 0.28625545])>>> XYZ = [19.01, 20.00, 21.78]
>>> XYZ_w = [95.05, 100.00, 108.88]
>>> L_A = 318.31
>>> Y_b = 20.0
>>> colour.XYZ_to_CIECAM02(XYZ, XYZ_w, L_A, Y_b)
CIECAM02_Specification(J=41.731091132513917, C=0.10470775717103062, h=219.04843265831178, s=2.3603053739196032, Q=195.37132596607671, M=0.10884217566914849, H=278.06073585667758, HC=None)>>> Lab_1 = [100.00000000, 21.57210357, 272.22819350]
>>> Lab_2 = [100.00000000, 426.67945353, 72.39590835]
>>> colour.delta_E(Lab_1, Lab_2)
94.035649026659485
>>> sorted(colour.DELTA_E_METHODS.keys())
['CAM02-LCD',
'CAM02-SCD',
'CAM02-UCS',
'CAM16-LCD',
'CAM16-SCD',
'CAM16-UCS',
'CIE 1976',
'CIE 1994',
'CIE 2000',
'CMC',
'DIN99',
'cie1976',
'cie1994',
'cie2000']>>> import numpy as np
>>> RGB = [0.17224810, 0.09170660, 0.06416938]
>>> M_T = np.random.random((24, 3))
>>> M_R = M_T + (np.random.random((24, 3)) - 0.5) * 0.5
>>> colour.colour_correction(RGB, M_T, M_R)
array([ 0.15205429, 0.08974029, 0.04141435])
>>> sorted(colour.COLOUR_CORRECTION_METHODS.keys())
[u'Cheung 2004', u'Finlayson 2015', u'Vandermonde']>>> colour.munsell_value(10.1488096782)
3.7462971142584354
>>> sorted(colour.MUNSELL_VALUE_METHODS.keys())
[u'ASTM D1535-08',
u'Ladd 1955',
u'McCamy 1987',
u'Moon 1943',
u'Munsell 1933',
u'Priest 1920',
u'Saunderson 1944',
u'astm2008']>>> colour.xyY_to_munsell_colour([0.38736945, 0.35751656, 0.59362000])
u'4.2YR 8.1/5.3'
>>> colour.munsell_colour_to_xyY('4.2YR 8.1/5.3')
array([ 0.38736945, 0.35751656, 0.59362 ])>>> import colour
>>> cmfs = colour.LMS_CMFS['Stockman & Sharpe 2 Degree Cone Fundamentals']
>>> colour.anomalous_trichromacy_cmfs_Machado2009(cmfs, np.array([15, 0, 0]))[450]
array([ 0.08912884, 0.0870524 , 0.955393 ])
>>> primaries = colour.DISPLAYS_RGB_PRIMARIES['Apple Studio Display']
>>> d_LMS = (15, 0, 0)
>>> colour.anomalous_trichromacy_matrix_Machado2009(cmfs, primaries, d_LMS)
array([[-0.27774652, 2.65150084, -1.37375432],
[ 0.27189369, 0.20047862, 0.52762768],
[ 0.00644047, 0.25921579, 0.73434374]])>>> colour.rayleigh_scattering_spd()
SpectralPowerDistribution([[ 3.60000000e+02, 5.99101337e-01],
[ 3.61000000e+02, 5.92170690e-01],
[ 3.62000000e+02, 5.85341006e-01],
...
[ 7.78000000e+02, 2.55208377e-02],
[ 7.79000000e+02, 2.53887969e-02],
[ 7.80000000e+02, 2.52576106e-02]],
interpolator=SpragueInterpolator,
interpolator_args={},
extrapolator=Extrapolator,
extrapolator_args={u'right': None, u'method': u'Constant', u'left': None})>>> colour.colour_quality_scale(colour.ILLUMINANTS_SPDS['F2'])
64.686416902221609>>> colour.colour_rendering_index(colour.ILLUMINANTS_SPDS['F2'])
64.151520202968015>>> colour.XYZ_to_spectral([0.07049534, 0.10080000, 0.09558313])
SpectralPowerDistribution([[ 3.60000000e+02, 7.96361498e-04],
[ 3.65000000e+02, 7.96489667e-04],
[ 3.70000000e+02, 7.96543669e-04],
...
[ 8.20000000e+02, 1.71014294e-04],
[ 8.25000000e+02, 1.71621924e-04],
[ 8.30000000e+02, 1.72026883e-04]],
interpolator=SpragueInterpolator,
interpolator_args={},
extrapolator=Extrapolator,
extrapolator_args={u'right': None, u'method': u'Constant', u'left': None})
>>> sorted(colour.REFLECTANCE_RECOVERY_METHODS.keys())
['Meng 2015', 'Smits 1999']>>> colour.uv_to_CCT([0.1978, 0.3122])
array([ 6.50751282e+03, 3.22335875e-03])
>>> sorted(colour.UV_TO_CCT_METHODS.keys())
[u'Ohno 2013', u'Robertson 1968', u'ohno2013', u'robertson1968']
>>> sorted(colour.UV_TO_CCT_METHODS.keys())
[u'Krystek 1985',
u'Ohno 2013',
u'Robertson 1968',
u'ohno2013',
u'robertson1968']
>>> sorted(colour.XY_TO_CCT_METHODS.keys())
[u'Hernandez 1999', u'McCamy 1992', u'hernandez1999', u'mccamy1992']
>>> sorted(colour.CCT_TO_XY_METHODS.keys())
[u'CIE Illuminant D Series', u'Kang 2002', su'cie_d', u'kang2002']>>> colour.RGB_colourspace_volume_MonteCarlo(colour.sRGB_COLOURSPACE)
857011.5>>> LUT = colour.read_LUT('ACES_Proxy_10_to_ACES.cube')
>>> print(LUT)
LUT2D - ACES Proxy 10 to ACES
-----------------------------
Dimensions : 2
Domain : [[0 0 0]
[1 1 1]]
Size : (32, 3)
>>> RGB = [0.17224810, 0.09170660, 0.06416938]
>>> LUT.apply(RGB)
array([ 0.00575674, 0.00181493, 0.00121419])Most of the objects are available from the colour.plotting namespace:
>>> from colour.plotting import *
>>> colour_style()>>> visible_spectrum_plot('CIE 1931 2 Degree Standard Observer')
>>> single_illuminant_spd_plot('F1')
>>> blackbody_spds = [
... colour.blackbody_spd(i, colour.SpectralShape(0, 10000, 10))
... for i in range(1000, 15000, 1000)
... ]
>>> multi_spd_plot(
... blackbody_spds,
... y_label='W / (sr m$^2$) / m',
... use_spds_colours=True,
... normalise_spds_colours=True,
... legend_location='upper right',
... bounding_box=(0, 1250, 0, 2.5e15))
>>> single_cmfs_plot(
... 'Stockman & Sharpe 2 Degree Cone Fundamentals',
... y_label='Sensitivity',
... bounding_box=(390, 870, 0, 1.1))
>>> mesopic_luminous_efficiency_function = (
... colour.mesopic_luminous_efficiency_function(0.2))
>>> multi_spd_plot(
... (mesopic_luminous_efficiency_function,
... colour.PHOTOPIC_LEFS['CIE 1924 Photopic Standard Observer'],
... colour.SCOTOPIC_LEFS['CIE 1951 Scotopic Standard Observer']),
... y_label='Luminous Efficiency',
... legend_location='upper right',
... y_tighten=True,
... margins=(0, 0, 0, .1))
>>> from colour.characterisation.dataset.colour_checkers.spds import (
... COLOURCHECKER_INDEXES_TO_NAMES_MAPPING)
>>> multi_spd_plot(
... [
... colour.COLOURCHECKERS_SPDS['BabelColor Average'][value]
... for key, value in sorted(
... COLOURCHECKER_INDEXES_TO_NAMES_MAPPING.items())
... ],
... use_spds_colours=True,
... title=('BabelColor Average - '
... 'Spectral Power Distributions'))
>>> colour_checker_plot('ColorChecker 2005', text_parameters={'visible': False})
>>> corresponding_chromaticities_prediction_plot(2, 'Von Kries', 'Bianco')
>>> planckian_locus_chromaticity_diagram_plot_CIE1960UCS(['A', 'B', 'C'])
>>> import numpy as np
>>> RGB = np.random.random((32, 32, 3))
>>> RGB_chromaticity_coordinates_chromaticity_diagram_plot_CIE1931(
... RGB, 'ITU-R BT.709', colourspaces=['ACEScg', 'S-Gamut', 'Pointer Gamut'])
>>> single_spd_colour_rendering_index_bars_plot(
... colour.ILLUMINANTS_SPDS['F2'])
If you would like to contribute to Colour, please refer to the following Contributing guide.
The changes are viewable on the Releases page.
The bibliography is available on the Bibliography page.
It is also viewable directly from the repository in BibTeX format.
Here is a list of notable colour science packages sorted by languages:
Python
- ColorPy by Kness, M.
- Colorspacious by Smith, N. J., et al.
- python-colormath by Taylor, G., et al.
.NET
- Colourful by Pažourek, T., et al.
Julia
- Colors.jl by Holy, T., et al.
Matlab & Octave
- COLORLAB by Malo, J., et al.
- Psychtoolbox by Brainard, D., et al.
- The Munsell and Kubelka-Munk Toolbox by Centore, P.
Colour by Colour Developers - 2013-2018
Copyright © 2013-2018 – Colour Developers – colour-science@googlegroups.com
This software is released under terms of New BSD License: http://opensource.org/licenses/BSD-3-Clause