1 Colour Science for Python¶
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.
Table of Contents
1.2 Features¶
Colour features a rich dataset and collection of objects, please see the features page for more information.
1.3 Online¶
Colour can be used online with Google Colab.
1.4 Installation¶
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-science
Colour can be easily installed from the Python Package Index by issuing this command in a shell:
$ pip install colour-science
The detailed installation procedure is described in the Installation Guide.
1.5 Usage¶
The two main references for Colour usage are the Colour Manual and the Jupyter Notebooks with detailed historical and theoretical context and images.
- Colour Manual
- Tutorial
- Basics
- Reference
- Colour
- Chromatic Adaptation
- Algebra
- Colour Appearance Models
- Biochemistry
- Colour Vision Deficiency
- Colour Characterisation
- Colorimetry
- Constants
- Contrast Sensitivity
- Continuous Signal
- Corresponding Chromaticities
- Colour Difference
- Input and Output
- Colour Models
- Colour Notation Systems
- Optical Phenomena
- Plotting
- Colour Quality
- Reflectance Recovery
- Colour Temperature
- Utilities
- Colour Volume
- Indices and tables
- Colour
- Bibliography
1.5.1 Examples¶
Most of the objects are available from the colour
namespace:
>>> import colour
1.5.1.1 Chromatic Adaptation - colour.adaptation
¶
>>> XYZ = [0.20654008, 0.12197225, 0.05136952]
>>> D65 = colour.ILLUMINANTS['CIE 1931 2 Degree Standard Observer']['D65']
>>> A = colour.ILLUMINANTS['CIE 1931 2 Degree Standard Observer']['A']
>>> colour.chromatic_adaptation(
... XYZ, colour.xy_to_XYZ(D65), colour.xy_to_XYZ(A))
array([ 0.2533053 , 0.13765138, 0.01543307])
>>> sorted(colour.CHROMATIC_ADAPTATION_METHODS.keys())
['CIE 1994', 'CMCCAT2000', 'Fairchild 1990', 'Von Kries']
1.5.1.2 Algebra - colour.algebra
¶
1.5.1.2.1 Kernel Interpolation¶
>>> 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])
1.5.1.2.2 Sprague (1880) Interpolation¶
>>> 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])
1.5.1.3 Colour Appearance Models - colour.appearance
¶
>>> XYZ = [0.20654008 * 100, 0.12197225 * 100, 0.05136952* 100]
>>> 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=34.434525727858997, C=67.365010921125915, h=22.279164147957076, s=62.814855853327131, Q=177.47124941102123, M=70.024939419291385, H=2.689608534423904, HC=None)
1.5.1.4 Colour Blindness - colour.blindness
¶
>>> 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]])
1.5.1.5 Colour Correction - colour characterisation
¶
>>> 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())
['Cheung 2004', 'Finlayson 2015', 'Vandermonde']
1.5.1.6 Colorimetry - colour.colorimetry
¶
1.5.1.6.1 Spectral Computations¶
>>> colour.sd_to_XYZ(colour.LIGHT_SOURCES_SDS['Neodimium Incandescent'])
array([ 36.94726204, 32.62076174, 13.0143849 ])
>>> sorted(colour.SPECTRAL_TO_XYZ_METHODS.keys())
['ASTM E308-15', 'Integration', 'astm2015']
1.5.1.6.2 Multi-Spectral Computations¶
>>> msd = 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_sds_to_XYZ(msd, 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())
['Integration']
1.5.1.6.3 Blackbody Spectral Radiance Computation¶
>>> colour.sd_blackbody(5000)
SpectralDistribution([[ 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={'right': None, 'method': 'Constant', 'left': None})
1.5.1.6.4 Dominant, Complementary Wavelength & Colour Purity Computation¶
>>> xy = [0.54369557, 0.32107944]
>>> xy_n = [0.31270000, 0.32900000]
>>> colour.dominant_wavelength(xy, xy_n)
(array(616.0),
array([ 0.68354746, 0.31628409]),
array([ 0.68354746, 0.31628409]))
1.5.1.6.5 Lightness Computation¶
>>> colour.lightness(12.19722535)
41.527875844653451
>>> sorted(colour.LIGHTNESS_METHODS.keys())
['CIE 1976',
'Fairchild 2010',
'Fairchild 2011',
'Glasser 1958',
'Lstar1976',
'Wyszecki 1963']
1.5.1.6.6 Luminance Computation¶
>>> colour.luminance(41.52787585)
12.197225353400775
>>> sorted(colour.LUMINANCE_METHODS.keys())
['ASTM D1535-08',
'CIE 1976',
'Fairchild 2010',
'Fairchild 2011',
'Newhall 1943',
'astm2008',
'cie1976']
1.5.1.6.7 Whiteness Computation¶
>>> XYZ = [95.00000000, 100.00000000, 105.00000000]
>>> XYZ_0 = [94.80966767, 100.00000000, 107.30513595]
>>> colour.whiteness(XYZ, XYZ_0)
array([ 93.756 , -1.33000001])
>>> sorted(colour.WHITENESS_METHODS.keys())
['ASTM E313',
'Berger 1959',
'CIE 2004',
'Ganz 1979',
'Stensby 1968',
'Taube 1960',
'cie2004']
1.5.1.6.8 Yellowness Computation¶
>>> XYZ = [95.00000000, 100.00000000, 105.00000000]
>>> colour.yellowness(XYZ)
11.065000000000003
>>> sorted(colour.YELLOWNESS_METHODS.keys())
['ASTM D1925', 'ASTM E313']
1.5.1.6.9 Luminous Flux, Efficiency & Efficacy Computation¶
>>> sd = colour.LIGHT_SOURCES_SDS['Neodimium Incandescent']
>>> colour.luminous_flux(sd)
23807.655527367202
>>> sd = colour.LIGHT_SOURCES_SDS['Neodimium Incandescent']
>>> colour.luminous_efficiency(sd)
0.19943935624521045
>>> sd = colour.LIGHT_SOURCES_SDS['Neodimium Incandescent']
>>> colour.luminous_efficacy(sd)
136.21708031547874
1.5.1.7 Contrast Sensitivity Function - colour.contrast
¶
>>> colour.contrast_sensitivity_function(u=4, X_0=60, E=65)
358.51180789884984
>>> sorted(colour.CONTRAST_SENSITIVITY_METHODS.keys())
['Barten 1999']
1.5.1.8 Colour Difference - colour.difference
¶
>>> 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']
1.5.1.9 IO - colour.io
¶
1.5.1.9.1 Images¶
>>> RGB = colour.read_image('Ishihara_Colour_Blindness_Test_Plate_3.png')
>>> RGB.shape
(276, 281, 3)
1.5.1.9.2 Look Up Table (LUT) Data¶
>>> LUT = colour.read_LUT('ACES_Proxy_10_to_ACES.cube')
>>> print(LUT)
LUT3x1D - 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])
1.5.1.10 Colour Models - colour.models
¶
1.5.1.10.1 CIE xyY Colourspace¶
>>> colour.XYZ_to_xyY([0.20654008, 0.12197225, 0.05136952])
array([ 0.54369557, 0.32107944, 0.12197225])
1.5.1.10.2 CIE L*a*b* Colourspace¶
>>> colour.XYZ_to_Lab([0.20654008, 0.12197225, 0.05136952])
array([ 41.52787529, 52.63858304, 26.92317922])
1.5.1.10.3 CIE L*u*v* Colourspace¶
>>> colour.XYZ_to_Luv([0.20654008, 0.12197225, 0.05136952])
array([ 41.52787529, 96.83626054, 17.75210149])
1.5.1.10.4 CIE 1960 UCS Colourspace¶
>>> colour.XYZ_to_UCS([0.20654008, 0.12197225, 0.05136952])
array([ 0.13769339, 0.12197225, 0.1053731 ])
1.5.1.10.5 CIE 1964 U*V*W* Colourspace¶
>>> XYZ = [0.20654008 * 100, 0.12197225 * 100, 0.05136952* 100]
>>> colour.XYZ_to_UVW(XYZ)
array([ 94.55035725, 11.55536523, 40.54757405])
1.5.1.10.6 Hunter L,a,b Colour Scale¶
>>> XYZ = [0.20654008 * 100, 0.12197225 * 100, 0.05136952* 100]
>>> colour.XYZ_to_Hunter_Lab(XYZ)
array([ 34.92452577, 47.06189858, 14.38615107])
1.5.1.10.7 Hunter Rd,a,b Colour Scale¶
>>> XYZ = [0.20654008 * 100, 0.12197225 * 100, 0.05136952* 100]
>>> colour.XYZ_to_Hunter_Rdab(XYZ)
array([ 12.197225 , 57.12537874, 17.46241341])
1.5.1.10.8 CAM02-LCD, CAM02-SCD, and CAM02-UCS Colourspaces - Luo, Cui and Li (2006)¶
>>> XYZ = [0.20654008 * 100, 0.12197225 * 100, 0.05136952* 100]
>>> XYZ_w = [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([ 47.16899898, 38.72623785, 15.8663383 ])
1.5.1.10.9 CAM16-LCD, CAM16-SCD, and CAM16-UCS Colourspaces - Li et al. (2017)¶
>>> XYZ = [0.20654008 * 100, 0.12197225 * 100, 0.05136952* 100]
>>> XYZ_w = [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([ 46.55542238, 40.22460974, 14.25288392]
1.5.1.10.10 IPT Colourspace¶
>>> colour.XYZ_to_IPT([0.20654008, 0.12197225, 0.05136952])
array([ 0.38426191, 0.38487306, 0.18886838])
1.5.1.10.11 DIN99 Colourspace¶
>>> Lab = [41.52787529, 52.63858304, 26.92317922]
>>> colour.Lab_to_DIN99(Lab)
array([ 53.22821988, 28.41634656, 3.89839552])
1.5.1.10.12 hdr-CIELAB Colourspace¶
>>> colour.XYZ_to_hdr_CIELab([0.20654008, 0.12197225, 0.05136952])
array([ 51.87002062, 60.4763385 , 32.14551912])
1.5.1.10.13 hdr-IPT Colourspace¶
>>> colour.XYZ_to_hdr_IPT([0.20654008, 0.12197225, 0.05136952])
array([ 25.18261761, -22.62111297, 3.18511729])
1.5.1.10.14 OSA UCS Colourspace¶
>>> XYZ = [0.20654008 * 100, 0.12197225 * 100, 0.05136952* 100]
>>> colour.XYZ_to_OSA_UCS(XYZ)
array([-3.0049979 , 2.99713697, -9.66784231])
1.5.1.10.15 JzAzBz Colourspace¶
>>> colour.XYZ_to_JzAzBz([0.20654008, 0.12197225, 0.05136952])
array([ 0.00535048, 0.00924302, 0.00526007])
1.5.1.10.16 Y’CbCr Colour Encoding¶
>>> colour.RGB_to_YCbCr([1.0, 1.0, 1.0])
array([ 0.92156863, 0.50196078, 0.50196078])
1.5.1.10.17 YCoCg Colour Encoding¶
>>> colour.RGB_to_YCoCg([0.75, 0.75, 0.0])
array([ 0.5625, 0.375 , 0.1875])
1.5.1.10.18 ICTCP Colour Encoding¶
>>> colour.RGB_to_ICTCP([0.45620519, 0.03081071, 0.04091952])
array([ 0.07351364, 0.00475253, 0.09351596])
1.5.1.10.19 HSV Colourspace¶
>>> colour.RGB_to_HSV([0.45620519, 0.03081071, 0.04091952])
array([ 0.99603944, 0.93246304, 0.45620519])
1.5.1.10.20 Prismatic Colourspace¶
>>> colour.RGB_to_Prismatic([0.25, 0.50, 0.75])
array([ 0.75 , 0.16666667, 0.33333333, 0.5 ])
1.5.1.10.21 RGB Colourspace and Transformations¶
>>> XYZ = [0.21638819, 0.12570000, 0.03847493]
>>> 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([ 0.45595571, 0.03039702, 0.04087245])
1.5.1.10.22 RGB Colourspace Derivation¶
>>> 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]])
1.5.1.10.23 RGB Colourspaces¶
>>> sorted(colour.RGB_COLOURSPACES.keys())
['ACES2065-1',
'ACEScc',
'ACEScct',
'ACEScg',
'ACESproxy',
'ALEXA Wide Gamut',
'Adobe RGB (1998)',
'Adobe Wide Gamut RGB',
'Apple RGB',
'Best RGB',
'Beta RGB',
'CIE RGB',
'Cinema Gamut',
'ColorMatch RGB',
'DCDM XYZ',
'DCI-P3',
'DCI-P3+',
'DJI D-Gamut',
'DRAGONcolor',
'DRAGONcolor2',
'Don RGB 4',
'ECI RGB v2',
'ERIMM RGB',
'Ekta Space PS 5',
'FilmLight E-Gamut',
'ITU-R BT.2020',
'ITU-R BT.470 - 525',
'ITU-R BT.470 - 625',
'ITU-R BT.709',
'Max RGB',
'NTSC',
'P3-D65',
'Pal/Secam',
'ProPhoto RGB',
'Protune Native',
'REDWideGamutRGB',
'REDcolor',
'REDcolor2',
'REDcolor3',
'REDcolor4',
'RIMM RGB',
'ROMM RGB',
'Russell RGB',
'S-Gamut',
'S-Gamut3',
'S-Gamut3.Cine',
'SMPTE 240M',
'Sharp RGB',
'V-Gamut',
'Xtreme RGB',
'aces',
'adobe1998',
'prophoto',
'sRGB']
1.5.1.10.24 OETFs¶
>>> sorted(colour.OETFS.keys())
['ARIB STD-B67',
'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']
1.5.1.10.25 OETFs Reverse¶
>>> sorted(colour.OETFS_REVERSE.keys())
['ARIB STD-B67',
'ITU-R BT.2100 HLD',
'ITU-R BT.2100 PQ',
'ITU-R BT.601',
'ITU-R BT.709',
'sRGB']
1.5.1.10.26 EOTFs¶
>>> sorted(colour.EOTFS.keys())
['DCDM',
'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']
1.5.1.10.27 EOTFs Reverse¶
>>> sorted(colour.EOTFS_REVERSE.keys())
['DCDM', 'ITU-R BT.1886', 'ITU-R BT.2100 HLG', 'ITU-R BT.2100 PQ']
1.5.1.10.28 OOTFs¶
>>> sorted(colour.OOTFS.keys())
['ITU-R BT.2100 HLG', 'ITU-R BT.2100 PQ']
1.5.1.10.29 OOTFs Reverse¶
>>> sorted(colour.OOTFs_REVERSE.keys())
['ITU-R BT.2100 HLG', 'ITU-R BT.2100 PQ']
1.5.1.10.30 Log Encoding / Decoding Curves¶
>>> sorted(colour.LOG_ENCODING_CURVES.keys())
['ACEScc',
'ACEScct',
'ACESproxy',
'ALEXA Log C',
'Canon Log',
'Canon Log 2',
'Canon Log 3',
'Cineon',
'D-Log',
'ERIMM RGB',
'Filmic Pro 6',
'Log3G10',
'Log3G12',
'PLog',
'Panalog',
'Protune',
'REDLog',
'REDLogFilm',
'S-Log',
'S-Log2',
'S-Log3',
'T-Log',
'V-Log',
'ViperLog']
1.5.1.11 Colour Notation Systems - colour.notation
¶
1.5.1.11.1 Munsell Value¶
>>> colour.munsell_value(12.23634268)
4.0824437076525664
>>> sorted(colour.MUNSELL_VALUE_METHODS.keys())
['ASTM D1535-08',
'Ladd 1955',
'McCamy 1987',
'Moon 1943',
'Munsell 1933',
'Priest 1920',
'Saunderson 1944',
'astm2008']
1.5.1.11.2 Munsell Colour¶
>>> colour.xyY_to_munsell_colour([0.38736945, 0.35751656, 0.59362000])
'4.2YR 8.1/5.3'
>>> colour.munsell_colour_to_xyY('4.2YR 8.1/5.3')
array([ 0.38736945, 0.35751656, 0.59362 ])
1.5.1.12 Optical Phenomena - colour.phenomena
¶
>>> colour.rayleigh_scattering_sd()
SpectralDistribution([[ 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={'right': None, 'method': 'Constant', 'left': None})
1.5.1.13 Light Quality - colour.quality
¶
1.5.1.13.1 Colour Rendering Index¶
>>> colour.colour_quality_scale(colour.ILLUMINANTS_SDS['FL2'])
64.017283509280588
>>> colour.COLOUR_QUALITY_SCALE_METHODS
('NIST CQS 7.4', 'NIST CQS 9.0')
1.5.1.13.2 Colour Quality Scale¶
>>> colour.colour_rendering_index(colour.ILLUMINANTS_SDS['FL2'])
64.151520202968015
1.5.1.14 Spectral Up-sampling & Reflectance Recovery - colour.recovery
¶
>>> colour.XYZ_to_sd([0.20654008, 0.12197225, 0.05136952])
SpectralDistribution([[ 3.60000000e+02, 7.73462151e-02],
[ 3.65000000e+02, 7.73632975e-02],
[ 3.70000000e+02, 7.74299705e-02],
...
[ 8.20000000e+02, 3.93126353e-01],
[ 8.25000000e+02, 3.93158148e-01],
[ 8.30000000e+02, 3.93163548e-01]],
interpolator=SpragueInterpolator,
interpolator_args={},
extrapolator=Extrapolator,
extrapolator_args={'right': None, 'method': 'Constant', 'left': None})
>>> sorted(colour.REFLECTANCE_RECOVERY_METHODS.keys())
['Meng 2015', 'Smits 1999']
1.5.1.16 Colour Volume - colour.volume
¶
>>> colour.RGB_colourspace_volume_MonteCarlo(colour.RGB_COLOURSPACE['sRGB'])
821958.30000000005
1.5.1.17 Plotting - colour.plotting
¶
Most of the objects are available from the colour.plotting
namespace:
>>> from colour.plotting import *
>>> colour_style()
1.5.1.17.1 Visible Spectrum¶
>>> plot_visible_spectrum('CIE 1931 2 Degree Standard Observer')
1.5.1.17.2 Spectral Distribution¶
>>> plot_single_illuminant_sd('FL1')
1.5.1.17.3 Blackbody¶
>>> blackbody_sds = [
... colour.sd_blackbody(i, colour.SpectralShape(0, 10000, 10))
... for i in range(1000, 15000, 1000)
... ]
>>> plot_multi_sds(
... blackbody_sds,
... y_label='W / (sr m$^2$) / m',
... use_sds_colours=True,
... normalise_sds_colours=True,
... legend_location='upper right',
... bounding_box=(0, 1250, 0, 2.5e15))
1.5.1.17.4 Colour Matching Functions¶
>>> plot_single_cmfs(
... 'Stockman & Sharpe 2 Degree Cone Fundamentals',
... y_label='Sensitivity',
... bounding_box=(390, 870, 0, 1.1))
1.5.1.17.5 Luminous Efficiency¶
>>> sd_mesopic_luminous_efficiency_function = (
... colour.sd_mesopic_luminous_efficiency_function(0.2))
>>> plot_multi_sds(
... (sd_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))
1.5.1.17.6 Colour Checker¶
>>> from colour.characterisation.dataset.colour_checkers.sds import (
... COLOURCHECKER_INDEXES_TO_NAMES_MAPPING)
>>> plot_multi_sds(
... [
... colour.COLOURCHECKERS_SDS['BabelColor Average'][value]
... for key, value in sorted(
... COLOURCHECKER_INDEXES_TO_NAMES_MAPPING.items())
... ],
... use_sds_colours=True,
... title=('BabelColor Average - '
... 'Spectral Distributions'))
>>> plot_single_colour_checker('ColorChecker 2005', text_parameters={'visible': False})
1.5.1.17.7 Chromaticities Prediction¶
>>> plot_corresponding_chromaticities_prediction(2, 'Von Kries', 'Bianco')
1.5.1.17.8 Colour Temperature¶
>>> plot_planckian_locus_in_chromaticity_diagram_CIE1960UCS(['A', 'B', 'C'])
1.5.1.17.9 Chromaticities¶
>>> import numpy as np
>>> RGB = np.random.random((32, 32, 3))
>>> plot_RGB_chromaticities_in_chromaticity_diagram_CIE1931(
... RGB, 'ITU-R BT.709', colourspaces=['ACEScg', 'S-Gamut'], show_pointer_gamut=True)
1.5.1.17.10 Colour Rendering Index¶
>>> plot_single_sd_colour_rendering_index_bars(
... colour.ILLUMINANTS_SDS['FL2'])
1.6 Contributing¶
If you would like to contribute to Colour, please refer to the following Contributing guide.
1.8 Bibliography¶
The bibliography is available on the Bibliography page.
It is also viewable directly from the repository in BibTeX format.
1.9 See Also¶
Here is a list of notable colour science packages sorted by languages:
Python
- Colorio by Schlömer, N.
- 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.