def test_n_dimensional_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition n-dimensional arrays support.
"""
XYZ_w = np.array([0.95045593, 1.00000000, 1.08905775])
XYZ_wr = np.array([0.96429568, 1.00000000, 0.82510460])
M = np.array([
[1.04257389, 0.03089108, -0.05281257],
[0.02219345, 1.00185663, -0.02107375],
[-0.00116488, -0.00342053, 0.76178907],
])
np.testing.assert_almost_equal(chromatic_adaptation_matrix_VonKries(
XYZ_w, XYZ_wr),
M,
decimal=7)
XYZ_w = np.tile(XYZ_w, (6, 1))
XYZ_wr = np.tile(XYZ_wr, (6, 1))
M = np.reshape(np.tile(M, (6, 1)), (6, 3, 3))
np.testing.assert_almost_equal(chromatic_adaptation_matrix_VonKries(
XYZ_w, XYZ_wr),
M,
decimal=7)
XYZ_w = np.reshape(XYZ_w, (2, 3, 3))
XYZ_wr = np.reshape(XYZ_wr, (2, 3, 3))
M = np.reshape(M, (2, 3, 3, 3))
np.testing.assert_almost_equal(chromatic_adaptation_matrix_VonKries(
XYZ_w, XYZ_wr),
M,
decimal=7)
def test_n_dimensional_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition n-dimensional arrays support.
"""
XYZ_w = np.array([1.09846607, 1.00000000, 0.35582280])
XYZ_wr = np.array([0.95042855, 1.00000000, 1.08890037])
M = np.array([[0.86876537, -0.14165393, 0.38719611],
[-0.10300724, 1.05840142, 0.15386462],
[0.00781674, 0.02678750, 2.96081771]])
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr),
M,
decimal=7)
XYZ_w = np.tile(XYZ_w, (6, 1))
XYZ_wr = np.tile(XYZ_wr, (6, 1))
M = np.reshape(np.tile(M, (6, 1)), (6, 3, 3))
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr),
M,
decimal=7)
XYZ_w = np.reshape(XYZ_w, (2, 3, 3))
XYZ_wr = np.reshape(XYZ_wr, (2, 3, 3))
M = np.reshape(M, (2, 3, 3, 3))
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr),
M,
decimal=7)
def test_n_dimensional_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition n-dimensional arrays support.
"""
XYZ_w = np.array([1.09846607, 1.00000000, 0.35582280])
XYZ_wr = np.array([0.95042855, 1.00000000, 1.08890037])
M = np.array([[0.86876537, -0.14165393, 0.38719611],
[-0.10300724, 1.05840142, 0.15386462],
[0.00781674, 0.02678750, 2.96081771]]) # yapf: disable
np.testing.assert_almost_equal(chromatic_adaptation_matrix_VonKries(
XYZ_w, XYZ_wr),
M,
decimal=7)
XYZ_w = np.tile(XYZ_w, (6, 1))
XYZ_wr = np.tile(XYZ_wr, (6, 1))
M = np.reshape(np.tile(M, (6, 1)), (6, 3, 3))
np.testing.assert_almost_equal(chromatic_adaptation_matrix_VonKries(
XYZ_w, XYZ_wr),
M,
decimal=7)
XYZ_w = np.reshape(XYZ_w, (2, 3, 3))
XYZ_wr = np.reshape(XYZ_wr, (2, 3, 3))
M = np.reshape(M, (2, 3, 3, 3))
np.testing.assert_almost_equal(chromatic_adaptation_matrix_VonKries(
XYZ_w, XYZ_wr),
M,
decimal=7)
def test_n_dimensional_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition n-dimensional arrays support.
"""
XYZ_w = np.array([0.95045593, 1.00000000, 1.08905775])
XYZ_wr = np.array([0.96429568, 1.00000000, 0.82510460])
M = chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr)
XYZ_w = np.tile(XYZ_w, (6, 1))
XYZ_wr = np.tile(XYZ_wr, (6, 1))
M = np.reshape(np.tile(M, (6, 1)), (6, 3, 3))
np.testing.assert_almost_equal(chromatic_adaptation_matrix_VonKries(
XYZ_w, XYZ_wr),
M,
decimal=7)
XYZ_w = np.reshape(XYZ_w, (2, 3, 3))
XYZ_wr = np.reshape(XYZ_wr, (2, 3, 3))
M = np.reshape(M, (2, 3, 3, 3))
np.testing.assert_almost_equal(chromatic_adaptation_matrix_VonKries(
XYZ_w, XYZ_wr),
M,
decimal=7)
def test_nan_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition nan support.
"""
cases = [-1.0, 0.0, 1.0, -np.inf, np.inf, np.nan]
cases = set(permutations(cases * 3, r=3))
for case in cases:
XYZ_w = np.array(case)
XYZ_wr = np.array(case)
chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr)
def test_nan_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition nan support.
"""
cases = [-1.0, 0.0, 1.0, -np.inf, np.inf, np.nan]
cases = set(permutations(cases * 3, r=3))
for case in cases:
XYZ_w = np.array(case)
XYZ_wr = np.array(case)
chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr)
def test_domain_range_scale_chromatic_adaptation_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition domain and range scale
support.
"""
XYZ_w = np.array([0.95045593, 1.00000000, 1.08905775])
XYZ_wr = np.array([0.96429568, 1.00000000, 0.82510460])
M = chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr)
d_r = (('reference', 1), (1, 1), (100, 0.01))
for scale, factor in d_r:
with domain_range_scale(scale):
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
XYZ_w * factor, XYZ_wr * factor),
M,
decimal=7)
def test_domain_range_scale_chromatic_adaptation_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition domain and range scale
support.
"""
XYZ_w = np.array([0.95045593, 1.00000000, 1.08905775])
XYZ_wr = np.array([0.96429568, 1.00000000, 0.82510460])
M = chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr)
d_r = (('reference', 1), (1, 1), (100, 0.01))
for scale, factor in d_r:
with domain_range_scale(scale):
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
XYZ_w * factor, XYZ_wr * factor),
M,
decimal=7)
def RGB_to_RGB(RGB,
input_colourspace,
output_colourspace,
chromatic_adaptation_transform='CAT02'):
"""
Converts from given input *RGB* colourspace to output *RGB* colourspace
using given *chromatic adaptation* method.
Parameters
----------
RGB : array_like
*RGB* colourspace array.
input_colourspace : RGB_Colourspace
*RGB* input colourspace.
output_colourspace : RGB_Colourspace
*RGB* output colourspace.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
*Chromatic adaptation* transform.
Returns
-------
ndarray
*RGB* colourspace array.
Notes
-----
- Input / output *RGB* colourspace arrays are in domain / range [0, 1].
- Input / output *RGB* colourspace arrays are assumed to be representing
linear light values.
Examples
--------
>>> from colour import sRGB_COLOURSPACE, PROPHOTO_RGB_COLOURSPACE
>>> RGB = np.array([0.01103742, 0.12734226, 0.11632971])
>>> RGB_to_RGB(
... RGB,
... sRGB_COLOURSPACE,
... PROPHOTO_RGB_COLOURSPACE) # doctest: +ELLIPSIS
array([ 0.0643538..., 0.1157289..., 0.1158038...])
"""
cat = chromatic_adaptation_matrix_VonKries(
xy_to_XYZ(input_colourspace.whitepoint),
xy_to_XYZ(output_colourspace.whitepoint),
chromatic_adaptation_transform)
M = dot_matrix(cat, input_colourspace.RGB_to_XYZ_matrix)
M = dot_matrix(output_colourspace.XYZ_to_RGB_matrix, M)
RGB = dot_vector(M, RGB)
return RGB
def test_n_dimensional_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition n-dimensional arrays support.
"""
XYZ_w = np.array([0.95045593, 1.00000000, 1.08905775])
XYZ_wr = np.array([0.96429568, 1.00000000, 0.82510460])
M = chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr)
XYZ_w = np.tile(XYZ_w, (6, 1))
XYZ_wr = np.tile(XYZ_wr, (6, 1))
M = np.reshape(np.tile(M, (6, 1)), (6, 3, 3))
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr), M, decimal=7)
XYZ_w = np.reshape(XYZ_w, (2, 3, 3))
XYZ_wr = np.reshape(XYZ_wr, (2, 3, 3))
M = np.reshape(M, (2, 3, 3, 3))
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(XYZ_w, XYZ_wr), M, decimal=7)
def RGB_to_RGB(RGB,
input_colourspace,
output_colourspace,
chromatic_adaptation_transform='CAT02'):
"""
Converts from given input *RGB* colourspace to output *RGB* colourspace
using given *chromatic adaptation* method.
Parameters
----------
RGB : array_like
*RGB* colourspace array.
input_colourspace : RGB_Colourspace
*RGB* input colourspace.
output_colourspace : RGB_Colourspace
*RGB* output colourspace.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild, 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
*Chromatic adaptation* transform.
Returns
-------
ndarray
*RGB* colourspace array.
Notes
-----
- *RGB* colourspace arrays are in domain [0, 1].
Examples
--------
>>> from colour import sRGB_COLOURSPACE, PROPHOTO_RGB_COLOURSPACE
>>> RGB = np.array([0.01103604, 0.12734466, 0.11631037])
>>> RGB_to_RGB(
... RGB,
... sRGB_COLOURSPACE,
... PROPHOTO_RGB_COLOURSPACE) # doctest: +ELLIPSIS
array([ 0.0643338..., 0.1157362..., 0.1157614...])
"""
cat = chromatic_adaptation_matrix_VonKries(
xy_to_XYZ(input_colourspace.whitepoint),
xy_to_XYZ(output_colourspace.whitepoint),
chromatic_adaptation_transform)
M = dot_matrix(cat, input_colourspace.RGB_to_XYZ_matrix)
M = dot_matrix(output_colourspace.XYZ_to_RGB_matrix, M)
RGB = dot_vector(M, RGB)
return RGB
def RGB_to_RGB_matrix(input_colourspace,
output_colourspace,
chromatic_adaptation_transform='CAT02'):
"""
Computes the matrix :math:`M` converting from given input *RGB*
colourspace to output *RGB* colourspace using given *chromatic
adaptation* method.
Parameters
----------
input_colourspace : RGB_Colourspace
*RGB* input colourspace.
output_colourspace : RGB_Colourspace
*RGB* output colourspace.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC', None}**,
*Chromatic adaptation* transform, if *None* no chromatic adaptation is
performed.
Returns
-------
ndarray
Conversion matrix :math:`M`.
Examples
--------
>>> from colour.models import sRGB_COLOURSPACE, PROPHOTO_RGB_COLOURSPACE
>>> RGB_to_RGB_matrix(sRGB_COLOURSPACE, PROPHOTO_RGB_COLOURSPACE)
... # doctest: +ELLIPSIS
array([[ 0.5288241..., 0.3340609..., 0.1373616...],
[ 0.0975294..., 0.8790074..., 0.0233981...],
[ 0.0163599..., 0.1066124..., 0.8772485...]])
"""
M = input_colourspace.RGB_to_XYZ_matrix
if chromatic_adaptation_transform is not None:
M_CAT = chromatic_adaptation_matrix_VonKries(
xy_to_XYZ(input_colourspace.whitepoint),
xy_to_XYZ(output_colourspace.whitepoint),
chromatic_adaptation_transform)
M = dot_matrix(M_CAT, input_colourspace.RGB_to_XYZ_matrix)
M = dot_matrix(output_colourspace.XYZ_to_RGB_matrix, M)
return M
def RGB_to_RGB_matrix(input_colourspace,
output_colourspace,
chromatic_adaptation_transform='CAT02'):
"""
Computes the matrix :math:`M` converting from given input *RGB*
colourspace to output *RGB* colourspace using given *chromatic
adaptation* method.
Parameters
----------
input_colourspace : RGB_Colourspace
*RGB* input colourspace.
output_colourspace : RGB_Colourspace
*RGB* output colourspace.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC', None}**,
*Chromatic adaptation* transform, if *None* no chromatic adaptation is
performed.
Returns
-------
ndarray
Conversion matrix :math:`M`.
Examples
--------
>>> from colour.models import sRGB_COLOURSPACE, PROPHOTO_RGB_COLOURSPACE
>>> RGB_to_RGB_matrix(sRGB_COLOURSPACE, PROPHOTO_RGB_COLOURSPACE)
... # doctest: +ELLIPSIS
array([[ 0.5288241..., 0.3340609..., 0.1373616...],
[ 0.0975294..., 0.8790074..., 0.0233981...],
[ 0.0163599..., 0.1066124..., 0.8772485...]])
"""
M = input_colourspace.RGB_to_XYZ_matrix
if chromatic_adaptation_transform is not None:
M_CAT = chromatic_adaptation_matrix_VonKries(
xy_to_XYZ(input_colourspace.whitepoint),
xy_to_XYZ(output_colourspace.whitepoint),
chromatic_adaptation_transform)
M = dot_matrix(M_CAT, input_colourspace.RGB_to_XYZ_matrix)
M = dot_matrix(output_colourspace.XYZ_to_RGB_matrix, M)
return M
def XYZ_to_RGB(XYZ,
illuminant_XYZ,
illuminant_RGB,
XYZ_to_RGB_matrix,
chromatic_adaptation_transform='CAT02',
encoding_cctf=None):
"""
Converts from *CIE XYZ* tristimulus values to *RGB* colourspace array.
Parameters
----------
XYZ : array_like
*CIE XYZ* tristimulus values.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* *xy* chromaticity coordinates
or *CIE xyY* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* *xy* chromaticity coordinates or
*CIE xyY* colourspace array.
XYZ_to_RGB_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC', None}**,
*Chromatic adaptation* transform, if *None* no chromatic adaptation is
performed.
encoding_cctf : object, optional
Encoding colour component transfer function (Encoding CCTF) or
opto-electronic transfer function (OETF / OECF).
Returns
-------
ndarray
*RGB* colourspace array.
Notes
-----
+--------------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+====================+=======================+===============+
| ``XYZ`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
| ``illuminant_XYZ`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
| ``illuminant_RGB`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
+--------------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+====================+=======================+===============+
| ``RGB`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
Examples
--------
>>> XYZ = np.array([0.21638819, 0.12570000, 0.03847493])
>>> illuminant_XYZ = np.array([0.34570, 0.35850])
>>> illuminant_RGB = np.array([0.31270, 0.32900])
>>> chromatic_adaptation_transform = 'Bradford'
>>> XYZ_to_RGB_matrix = np.array(
... [[3.24062548, -1.53720797, -0.49862860],
... [-0.96893071, 1.87575606, 0.04151752],
... [0.05571012, -0.20402105, 1.05699594]]
... )
>>> XYZ_to_RGB(XYZ, illuminant_XYZ, illuminant_RGB, XYZ_to_RGB_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.4559557..., 0.0303970..., 0.0408724...])
"""
XYZ = to_domain_1(XYZ)
if chromatic_adaptation_transform is not None:
M_CAT = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
transform=chromatic_adaptation_transform)
XYZ = dot_vector(M_CAT, XYZ)
RGB = dot_vector(XYZ_to_RGB_matrix, XYZ)
if encoding_cctf is not None:
with domain_range_scale('ignore'):
RGB = encoding_cctf(RGB)
return from_range_1(RGB)
def test_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition.
"""
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([1.09846607, 1.00000000, 0.35582280]),
np.array([0.95042855, 1.00000000, 1.08890037])),
np.array([[0.86876537, -0.14165393, 0.38719611],
[-0.10300724, 1.05840142, 0.15386462],
[0.00781674, 0.02678750, 2.96081771]]),
decimal=7) # yapf: disable
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.99092745, 1.00000000, 0.85313273]),
np.array([1.01679082, 1.00000000, 0.67610122])),
np.array([[1.03379528, 0.03065322, -0.04486819],
[0.02195826, 0.99354348, -0.01793687],
[-0.00102726, -0.00281712, 0.79698769]]),
decimal=7) # yapf: disable
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.98070597, 1.00000000, 1.18224949]),
np.array([0.92833635, 1.00000000, 1.03664720])),
np.linalg.inv(
chromatic_adaptation_matrix_VonKries(
np.array([0.92833635, 1.00000000, 1.03664720]),
np.array([0.98070597, 1.00000000, 1.18224949]))))
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([1.09846607, 1.00000000, 0.35582280]),
np.array([0.95042855, 1.00000000, 1.08890037]),
transform='XYZ Scaling'),
np.array([[0.86523251, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, 3.06023214]]),
decimal=7) # yapf: disable
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([1.09846607, 1.00000000, 0.35582280]),
np.array([0.95042855, 1.00000000, 1.08890037]),
transform='Bradford'),
np.array([[0.84467949, -0.11793553, 0.39489408],
[-0.13664085, 1.10412369, 0.12919812],
[0.07986716, -0.13493155, 3.19288296]]),
decimal=7) # yapf: disable
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([1.09846607, 1.00000000, 0.35582280]),
np.array([0.95042855, 1.00000000, 1.08890037]),
transform='Von Kries'),
np.array([[0.93949221, -0.23393727, 0.42820614],
[-0.02569635, 1.02638463, 0.00517656],
[0.00000000, 0.00000000, 3.06023214]]),
decimal=7) # yapf: disable
def RGB_to_XYZ(RGB,
illuminant_RGB,
illuminant_XYZ,
RGB_to_XYZ_matrix,
chromatic_adaptation_transform='CAT02',
decoding_cctf=None):
"""
Converts given *RGB* colourspace array to *CIE XYZ* tristimulus values.
Parameters
----------
RGB : array_like
*RGB* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* chromaticity coordinates or *CIE xyY*
colourspace array.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* chromaticity coordinates or
*CIE xyY* colourspace array.
RGB_to_XYZ_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC', None}**,
*Chromatic adaptation* transform, if *None* no chromatic adaptation is
performed.
decoding_cctf : object, optional
Decoding colour component transfer function (Decoding CCTF) or
electro-optical transfer function (EOTF / EOCF).
Returns
-------
ndarray
*CIE XYZ* tristimulus values.
Notes
-----
+--------------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+====================+=======================+===============+
| ``RGB`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
| ``illuminant_XYZ`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
| ``illuminant_RGB`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
+--------------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+====================+=======================+===============+
| ``XYZ`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
Examples
--------
>>> RGB = np.array([0.45595571, 0.03039702, 0.04087245])
>>> illuminant_RGB = np.array([0.31270, 0.32900])
>>> illuminant_XYZ = np.array([0.34570, 0.35850])
>>> chromatic_adaptation_transform = 'Bradford'
>>> RGB_to_XYZ_matrix = np.array(
... [[0.41240000, 0.35760000, 0.18050000],
... [0.21260000, 0.71520000, 0.07220000],
... [0.01930000, 0.11920000, 0.95050000]]
... )
>>> RGB_to_XYZ(RGB, illuminant_RGB, illuminant_XYZ, RGB_to_XYZ_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.2163881..., 0.1257 , 0.0384749...])
"""
RGB = to_domain_1(RGB)
if decoding_cctf is not None:
with domain_range_scale('ignore'):
RGB = decoding_cctf(RGB)
XYZ = dot_vector(RGB_to_XYZ_matrix, RGB)
if chromatic_adaptation_transform is not None:
M_CAT = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
transform=chromatic_adaptation_transform)
XYZ = dot_vector(M_CAT, XYZ)
return from_range_1(XYZ)
def XYZ_to_RGB(XYZ,
illuminant_XYZ,
illuminant_RGB,
XYZ_to_RGB_matrix,
chromatic_adaptation_transform='CAT02',
encoding_cctf=None):
"""
Converts from *CIE XYZ* tristimulus values to *RGB* colourspace array.
Parameters
----------
XYZ : array_like
*CIE XYZ* tristimulus values.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* *xy* chromaticity coordinates
or *CIE xyY* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* *xy* chromaticity coordinates or
*CIE xyY* colourspace array.
XYZ_to_RGB_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC', None}**,
*Chromatic adaptation* transform, if *None* no chromatic adaptation is
performed.
encoding_cctf : object, optional
Encoding colour component transfer function (Encoding CCTF) or
opto-electronic transfer function (OETF / OECF).
Returns
-------
ndarray
*RGB* colourspace array.
Notes
-----
+--------------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+====================+=======================+===============+
| ``XYZ`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
| ``illuminant_XYZ`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
| ``illuminant_RGB`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
+--------------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+====================+=======================+===============+
| ``RGB`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
Examples
--------
>>> XYZ = np.array([0.21638819, 0.12570000, 0.03847493])
>>> illuminant_XYZ = np.array([0.34570, 0.35850])
>>> illuminant_RGB = np.array([0.31270, 0.32900])
>>> chromatic_adaptation_transform = 'Bradford'
>>> XYZ_to_RGB_matrix = np.array(
... [[3.24062548, -1.53720797, -0.49862860],
... [-0.96893071, 1.87575606, 0.04151752],
... [0.05571012, -0.20402105, 1.05699594]]
... )
>>> XYZ_to_RGB(XYZ, illuminant_XYZ, illuminant_RGB, XYZ_to_RGB_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.4559557..., 0.0303970..., 0.0408724...])
"""
XYZ = to_domain_1(XYZ)
if chromatic_adaptation_transform is not None:
M_CAT = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
transform=chromatic_adaptation_transform)
XYZ = dot_vector(M_CAT, XYZ)
RGB = dot_vector(XYZ_to_RGB_matrix, XYZ)
if encoding_cctf is not None:
with domain_range_scale('ignore'):
RGB = encoding_cctf(RGB)
return from_range_1(RGB)
def RGB_to_XYZ(RGB,
illuminant_RGB,
illuminant_XYZ,
RGB_to_XYZ_matrix,
chromatic_adaptation_transform='CAT02',
decoding_cctf=None):
"""
Converts given *RGB* colourspace array to *CIE XYZ* tristimulus values.
Parameters
----------
RGB : array_like
*RGB* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* chromaticity coordinates or *CIE xyY*
colourspace array.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* chromaticity coordinates or
*CIE xyY* colourspace array.
RGB_to_XYZ_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC', None}**,
*Chromatic adaptation* transform, if *None* no chromatic adaptation is
performed.
decoding_cctf : object, optional
Decoding colour component transfer function (Decoding CCTF) or
electro-optical transfer function (EOTF / EOCF).
Returns
-------
ndarray
*CIE XYZ* tristimulus values.
Notes
-----
+--------------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+====================+=======================+===============+
| ``RGB`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
| ``illuminant_XYZ`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
| ``illuminant_RGB`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
+--------------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+====================+=======================+===============+
| ``XYZ`` | [0, 1] | [0, 1] |
+--------------------+-----------------------+---------------+
Examples
--------
>>> RGB = np.array([0.45595571, 0.03039702, 0.04087245])
>>> illuminant_RGB = np.array([0.31270, 0.32900])
>>> illuminant_XYZ = np.array([0.34570, 0.35850])
>>> chromatic_adaptation_transform = 'Bradford'
>>> RGB_to_XYZ_matrix = np.array(
... [[0.41240000, 0.35760000, 0.18050000],
... [0.21260000, 0.71520000, 0.07220000],
... [0.01930000, 0.11920000, 0.95050000]]
... )
>>> RGB_to_XYZ(RGB, illuminant_RGB, illuminant_XYZ, RGB_to_XYZ_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.2163881..., 0.1257 , 0.0384749...])
"""
RGB = to_domain_1(RGB)
if decoding_cctf is not None:
with domain_range_scale('ignore'):
RGB = decoding_cctf(RGB)
XYZ = dot_vector(RGB_to_XYZ_matrix, RGB)
if chromatic_adaptation_transform is not None:
M_CAT = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
transform=chromatic_adaptation_transform)
XYZ = dot_vector(M_CAT, XYZ)
return from_range_1(XYZ)
def XYZ_to_RGB(XYZ,
illuminant_XYZ,
illuminant_RGB,
XYZ_to_RGB_matrix,
chromatic_adaptation_transform='CAT02',
OECF=None):
"""
Converts from *CIE XYZ* tristimulus values to given *RGB* colourspace.
Parameters
----------
XYZ : array_like
*CIE XYZ* tristimulus values.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* *xy* chromaticity coordinates
or *CIE xyY* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* *xy* chromaticity coordinates or
*CIE xyY* colourspace array.
XYZ_to_RGB_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild, 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
*Chromatic adaptation* transform.
OECF : object, optional
*Opto-electronic conversion function*.
Returns
-------
ndarray
*RGB* colourspace array.
Notes
-----
- Input *CIE XYZ* tristimulus values are in domain [0, 1].
- Input *illuminant_XYZ* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Input *illuminant_RGB* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Output *RGB* colourspace array is in domain [0, 1].
Examples
--------
>>> XYZ = np.array([0.07049534, 0.10080000, 0.09558313])
>>> illuminant_XYZ = np.array([0.34567, 0.35850])
>>> illuminant_RGB = np.array([0.31271, 0.32902])
>>> chromatic_adaptation_transform = 'Bradford'
>>> XYZ_to_RGB_matrix = np.array([
... [3.24100326, -1.53739899, -0.49861587],
... [-0.96922426, 1.87592999, 0.04155422],
... [0.05563942, -0.20401120, 1.05714897]])
>>> XYZ_to_RGB(
... XYZ,
... illuminant_XYZ,
... illuminant_RGB,
... XYZ_to_RGB_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.0110360..., 0.1273446..., 0.1163103...])
"""
M = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
transform=chromatic_adaptation_transform)
XYZ_a = dot_vector(M, XYZ)
RGB = dot_vector(XYZ_to_RGB_matrix, XYZ_a)
if OECF is not None:
RGB = OECF(RGB)
return RGB
def XYZ_to_RGB(XYZ,
illuminant_XYZ,
illuminant_RGB,
XYZ_to_RGB_matrix,
chromatic_adaptation_transform='CAT02',
encoding_cctf=None):
"""
Converts from *CIE XYZ* tristimulus values to given *RGB* colourspace.
Parameters
----------
XYZ : array_like
*CIE XYZ* tristimulus values.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* *xy* chromaticity coordinates
or *CIE xyY* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* *xy* chromaticity coordinates or
*CIE xyY* colourspace array.
XYZ_to_RGB_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
*Chromatic adaptation* transform.
encoding_cctf : object, optional
Encoding colour component transfer function (Encoding CCTF) or
opto-electronic transfer function (OETF / OECF).
Returns
-------
ndarray
*RGB* colourspace array.
Notes
-----
- Input *CIE XYZ* tristimulus values are in domain [0, 1].
- Input *illuminant_XYZ* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Input *illuminant_RGB* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Output *RGB* colourspace array is in range [0, 1].
Examples
--------
>>> XYZ = np.array([0.07049534, 0.10080000, 0.09558313])
>>> illuminant_XYZ = np.array([0.34570, 0.35850])
>>> illuminant_RGB = np.array([0.31270, 0.32900])
>>> chromatic_adaptation_transform = 'Bradford'
>>> XYZ_to_RGB_matrix = np.array([
... [3.24062548, -1.53720797, -0.49862860],
... [-0.96893071, 1.87575606, 0.04151752],
... [0.05571012, -0.20402105, 1.05699594]])
>>> XYZ_to_RGB(
... XYZ,
... illuminant_XYZ,
... illuminant_RGB,
... XYZ_to_RGB_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.0110015..., 0.1273504..., 0.1163271...])
"""
M = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
transform=chromatic_adaptation_transform)
XYZ_a = dot_vector(M, XYZ)
RGB = dot_vector(XYZ_to_RGB_matrix, XYZ_a)
if encoding_cctf is not None:
RGB = encoding_cctf(RGB)
return RGB
def test_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition.
"""
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.96429568, 1.00000000, 0.82510460])),
np.array([
[1.04257389, 0.03089108, -0.05281257],
[0.02219345, 1.00185663, -0.02107375],
[-0.00116488, -0.00342053, 0.76178907],
]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([1.09846607, 1.00000000, 0.35582280])),
np.array([
[1.17159793, 0.16088780, -0.16158366],
[0.11462057, 0.96182051, -0.06497572],
[-0.00413024, -0.00912739, 0.33871096],
]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.99144661, 1.00000000, 0.67315942])),
np.linalg.inv(
chromatic_adaptation_matrix_VonKries(
np.array([0.99144661, 1.00000000, 0.67315942]),
np.array([0.95045593, 1.00000000, 1.08905775]))),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.96429568, 1.00000000, 0.82510460]),
transform='XYZ Scaling'),
np.array([
[1.01456117, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, 0.75763163],
]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.96429568, 1.00000000, 0.82510460]),
transform='Bradford'),
np.array([
[1.04792979, 0.02294687, -0.05019227],
[0.02962781, 0.99043443, -0.01707380],
[-0.00924304, 0.01505519, 0.75187428],
]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.96429568, 1.00000000, 0.82510460]),
transform='Von Kries'),
np.array([
[1.01611856, 0.05535971, -0.05219186],
[0.00608087, 0.99555604, -0.00122642],
[0.00000000, 0.00000000, 0.75763163],
]),
decimal=7)
def test_chromatic_adaptation_matrix_VonKries(self):
"""
Tests
:func:`colour.adaptation.vonkries.chromatic_adaptation_matrix_VonKries`
definition.
"""
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([1.09846607, 1., 0.3558228]),
np.array([0.95042855, 1., 1.08890037])),
np.array([[0.86876537, -0.14165393, 0.38719611],
[-0.10300724, 1.05840142, 0.15386462],
[0.00781674, 0.0267875, 2.96081771]]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.99092745, 1., 0.85313273]),
np.array([1.01679082, 1., 0.67610122])),
np.array([[1.03379528e+00, 3.06532172e-02, -4.48681876e-02],
[2.19582633e-02, 9.93543483e-01, -1.79368671e-02],
[-1.02726253e-03, -2.81711777e-03, 7.96987686e-01]]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.98070597, 1., 1.18224949]),
np.array([0.92833635, 1., 1.0366472])),
np.linalg.inv(chromatic_adaptation_matrix_VonKries(
np.array([0.92833635, 1., 1.0366472]),
np.array([0.98070597, 1., 1.18224949]))))
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([1.09846607, 1., 0.3558228]),
np.array([0.95042855, 1., 1.08890037]),
transform='XYZ Scaling'),
np.array([[0.86523251, 0., 0.],
[0., 1., 0.],
[0., 0., 3.06023214]]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([1.09846607, 1., 0.3558228]),
np.array([0.95042855, 1., 1.08890037]),
transform='Bradford'),
np.array([[0.84467949, -0.11793553, 0.39489408],
[-0.13664085, 1.10412369, 0.12919812],
[0.07986716, -0.13493155, 3.19288296]]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([1.09846607, 1., 0.3558228]),
np.array([0.95042855, 1., 1.08890037]),
transform='Von Kries'),
np.array([[0.93949221, -0.23393727, 0.42820614],
[-0.02569635, 1.02638463, 0.00517656],
[0., 0., 3.06023214]]),
decimal=7)
def RGB_to_XYZ(RGB,
illuminant_RGB,
illuminant_XYZ,
RGB_to_XYZ_matrix,
chromatic_adaptation_transform='CAT02',
inverse_transfer_function=None):
"""
Converts from *RGB* colourspace to *CIE XYZ* colourspace using given
*RGB* colourspace matrix, *illuminants*, *chromatic adaptation* method,
*normalised primary matrix* and *transfer function*.
Parameters
----------
RGB : array_like, (3,)
*RGB* colourspace matrix.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* chromaticity coordinates.
illuminant_XYZ : array_like
*CIE XYZ* colourspace *illuminant* chromaticity coordinates.
RGB_to_XYZ_matrix : array_like, (3, 3)
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp', 'Fairchild,
'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco', 'Bianco PC'},
*Chromatic adaptation* transform.
inverse_transfer_function : object, optional
*Inverse transfer function*.
Returns
-------
ndarray, (3,)
*CIE XYZ* colourspace matrix.
Notes
-----
- Input *RGB* colourspace matrix is in domain [0, 1].
- Input *illuminant_RGB* *xy* chromaticity coordinates are in domain
[0, 1].
- Input *illuminant_XYZ* *xy* chromaticity coordinates are in domain
[0, 1].
- Output *CIE XYZ* colourspace matrix is in domain [0, 1].
Examples
--------
>>> RGB = np.array([0.01103604, 0.12734466, 0.11631037])
>>> illuminant_RGB = (0.31271, 0.32902)
>>> illuminant_XYZ = (0.34567, 0.35850)
>>> chromatic_adaptation_transform = 'Bradford'
>>> RGB_to_XYZ_matrix = np.array([
... [0.41238656, 0.35759149, 0.18045049],
... [0.21263682, 0.71518298, 0.0721802],
... [0.01933062, 0.11919716, 0.95037259]])
>>> RGB_to_XYZ(
... RGB,
... illuminant_RGB,
... illuminant_XYZ,
... RGB_to_XYZ_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.0704953..., 0.1008 , 0.0955831...])
"""
RGB = np.ravel(RGB)
if inverse_transfer_function is not None:
RGB = np.array([inverse_transfer_function(x) for x in RGB])
XYZ = np.dot(RGB_to_XYZ_matrix.reshape((3, 3)), RGB.reshape((3, 1)))
cat = chromatic_adaptation_matrix_VonKries(
xy_to_XYZ(illuminant_RGB),
xy_to_XYZ(illuminant_XYZ),
transform=chromatic_adaptation_transform)
XYZ_a = np.dot(cat, XYZ.reshape((3, 1)))
return np.ravel(XYZ_a)
def XYZ_to_RGB(XYZ,
illuminant_XYZ,
illuminant_RGB,
XYZ_to_RGB_matrix,
chromatic_adaptation_transform='CAT02',
OECF=None):
"""
Converts from *CIE XYZ* tristimulus values to given *RGB* colourspace.
Parameters
----------
XYZ : array_like
*CIE XYZ* tristimulus values.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* *xy* chromaticity coordinates
or *CIE xyY* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* *xy* chromaticity coordinates or
*CIE xyY* colourspace array.
XYZ_to_RGB_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild, 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
*Chromatic adaptation* transform.
OECF : object, optional
*Opto-electronic conversion function*.
Returns
-------
ndarray
*RGB* colourspace array.
Notes
-----
- Input *CIE XYZ* tristimulus values are in domain [0, 1].
- Input *illuminant_XYZ* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Input *illuminant_RGB* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Output *RGB* colourspace array is in domain [0, 1].
Examples
--------
>>> XYZ = np.array([0.07049534, 0.10080000, 0.09558313])
>>> illuminant_XYZ = np.array([0.34567, 0.35850])
>>> illuminant_RGB = np.array([0.31271, 0.32902])
>>> chromatic_adaptation_transform = 'Bradford'
>>> XYZ_to_RGB_matrix = np.array([
... [3.24100326, -1.53739899, -0.49861587],
... [-0.96922426, 1.87592999, 0.04155422],
... [0.05563942, -0.20401120, 1.05714897]])
>>> XYZ_to_RGB(
... XYZ,
... illuminant_XYZ,
... illuminant_RGB,
... XYZ_to_RGB_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.0110360..., 0.1273446..., 0.1163103...])
"""
M = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
transform=chromatic_adaptation_transform)
XYZ_a = dot_vector(M, XYZ)
RGB = dot_vector(XYZ_to_RGB_matrix, XYZ_a)
if OECF is not None:
RGB = OECF(RGB)
return RGB
def RGB_to_XYZ(RGB,
illuminant_RGB,
illuminant_XYZ,
RGB_to_XYZ_matrix,
chromatic_adaptation_transform='CAT02',
EOCF=None):
"""
Converts from given *RGB* colourspace to *CIE XYZ* tristimulus values.
Parameters
----------
RGB : array_like
*RGB* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* chromaticity coordinates or *CIE xyY*
colourspace array.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* chromaticity coordinates or
*CIE xyY* colourspace array.
RGB_to_XYZ_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild, 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
*Chromatic adaptation* transform.
EOCF : object, optional
*Electro-optical conversion function*.
Returns
-------
ndarray
*CIE XYZ* tristimulus values.
Notes
-----
- Input *RGB* colourspace array is in domain [0, 1].
- Input *illuminant_RGB* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Input *illuminant_XYZ* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Output *CIE XYZ* tristimulus values are in domain [0, 1].
Examples
--------
>>> RGB = np.array([0.01103604, 0.12734466, 0.11631037])
>>> illuminant_RGB = np.array([0.31271, 0.32902])
>>> illuminant_XYZ = np.array([0.34567, 0.35850])
>>> chromatic_adaptation_transform = 'Bradford'
>>> RGB_to_XYZ_matrix = np.array([
... [0.41238656, 0.35759149, 0.18045049],
... [0.21263682, 0.71518298, 0.07218020],
... [0.01933062, 0.11919716, 0.95037259]])
>>> RGB_to_XYZ(
... RGB,
... illuminant_RGB,
... illuminant_XYZ,
... RGB_to_XYZ_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.0704953..., 0.1008 , 0.0955831...])
"""
if EOCF is not None:
RGB = EOCF(RGB)
M = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
transform=chromatic_adaptation_transform)
XYZ = dot_vector(RGB_to_XYZ_matrix, RGB)
XYZ_a = dot_vector(M, XYZ)
return XYZ_a
def RGB_to_XYZ(RGB,
illuminant_RGB,
illuminant_XYZ,
RGB_to_XYZ_matrix,
chromatic_adaptation_transform='CAT02',
decoding_cctf=None):
"""
Converts from given *RGB* colourspace to *CIE XYZ* tristimulus values.
Parameters
----------
RGB : array_like
*RGB* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* chromaticity coordinates or *CIE xyY*
colourspace array.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* chromaticity coordinates or
*CIE xyY* colourspace array.
RGB_to_XYZ_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
*Chromatic adaptation* transform.
decoding_cctf : object, optional
Decoding colour component transfer function (Decoding CCTF) or
electro-optical transfer function (EOTF / EOCF).
Returns
-------
ndarray
*CIE XYZ* tristimulus values.
Notes
-----
- Input *RGB* colourspace array is in domain [0, 1].
- Input *illuminant_RGB* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Input *illuminant_XYZ* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Output *CIE XYZ* tristimulus values are in range [0, 1].
Examples
--------
>>> RGB = np.array([0.01100154, 0.12735048, 0.11632713])
>>> illuminant_RGB = np.array([0.31270, 0.32900])
>>> illuminant_XYZ = np.array([0.34570, 0.35850])
>>> chromatic_adaptation_transform = 'Bradford'
>>> RGB_to_XYZ_matrix = np.array([
... [0.41240000, 0.35760000, 0.18050000],
... [0.21260000, 0.71520000, 0.07220000],
... [0.01930000, 0.11920000, 0.95050000]])
>>> RGB_to_XYZ(
... RGB,
... illuminant_RGB,
... illuminant_XYZ,
... RGB_to_XYZ_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.0704953..., 0.1008 , 0.0955831...])
"""
if decoding_cctf is not None:
RGB = decoding_cctf(RGB)
M = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
transform=chromatic_adaptation_transform)
XYZ = dot_vector(RGB_to_XYZ_matrix, RGB)
XYZ_a = dot_vector(M, XYZ)
return XYZ_a
def camera_space_to_XYZ_matrix(xy,
CCT_calibration_illuminant_1,
CCT_calibration_illuminant_2,
M_color_matrix_1,
M_color_matrix_2,
M_camera_calibration_1,
M_camera_calibration_2,
analog_balance,
M_forward_matrix_1,
M_forward_matrix_2,
chromatic_adaptation_transform='Bradford'):
"""
Returns the *Camera Space* to *CIE XYZ* matrix for given *xy* white
balance chromaticity coordinates.
Parameters
----------
xy : array_like
*xy* white balance chromaticity coordinates.
CCT_calibration_illuminant_1 : numeric
Correlated colour temperature of *CalibrationIlluminant1*.
CCT_calibration_illuminant_2 : numeric
Correlated colour temperature of *CalibrationIlluminant2*.
M_color_matrix_1 : array_like
*ColorMatrix1* tag matrix.
M_color_matrix_2 : array_like
*ColorMatrix2* tag matrix.
M_camera_calibration_1 : array_like
*CameraCalibration1* tag matrix.
M_camera_calibration_2 : array_like
*CameraCalibration2* tag matrix.
analog_balance : array_like
*AnalogBalance* tag vector.
M_forward_matrix_1 : array_like
*ForwardMatrix1* tag matrix.
M_forward_matrix_2 : array_like
*ForwardMatrix2* tag matrix.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
Chromatic adaptation transform.
Returns
-------
ndarray
*Camera Space* to *CIE XYZ* matrix.
Notes
-----
- The reference illuminant is D50 as defined per
:attr:`colour_hdri.models.dataset.dng.ADOBE_DNG_XYZ_ILLUMINANT`
attribute.
References
----------
- :cite:`AdobeSystems2012f`
- :cite:`AdobeSystems2012g`
- :cite:`AdobeSystems2015d`
- :cite:`McGuffog2012a`
Examples
--------
>>> M_color_matrix_1 = np.array(
... [[0.5309, -0.0229, -0.0336],
... [-0.6241, 1.3265, 0.3337],
... [-0.0817, 0.1215, 0.6664]])
>>> M_color_matrix_2 = np.array(
... [[0.4716, 0.0603, -0.0830],
... [-0.7798, 1.5474, 0.2480],
... [-0.1496, 0.1937, 0.6651]])
>>> M_camera_calibration_1 = np.identity(3)
>>> M_camera_calibration_2 = np.identity(3)
>>> analog_balance = np.ones(3)
>>> M_forward_matrix_1 = np.array(
... [[0.8924, -0.1041, 0.1760],
... [0.4351, 0.6621, -0.0972],
... [0.0505, -0.1562, 0.9308]])
>>> M_forward_matrix_2 = np.array(
... [[0.8924, -0.1041, 0.1760],
... [0.4351, 0.6621, -0.0972],
... [0.0505, -0.1562, 0.9308]])
>>> camera_space_to_XYZ_matrix( # doctest: +ELLIPSIS
... np.array([0.32816244, 0.34698169]),
... 2850,
... 6500,
... M_color_matrix_1,
... M_color_matrix_2,
... M_camera_calibration_1,
... M_camera_calibration_2,
... analog_balance,
... M_forward_matrix_1,
... M_forward_matrix_2)
array([[ 2.1604087..., -0.1041... , 0.2722498...],
[ 1.0533324..., 0.6621... , -0.1503561...],
[ 0.1222553..., -0.1562... , 1.4398304...]])
"""
# *ForwardMatrix1* and *ForwardMatrix2* are not included in the camera
# profile.
if is_identity(M_forward_matrix_1) and is_identity(M_forward_matrix_2):
M_camera_to_XYZ = np.linalg.inv(
XYZ_to_camera_space_matrix(xy, CCT_calibration_illuminant_1,
CCT_calibration_illuminant_2,
M_color_matrix_1, M_color_matrix_2,
M_camera_calibration_1,
M_camera_calibration_2, analog_balance))
M_CAT = chromatic_adaptation_matrix_VonKries(
xy_to_XYZ(xy), xy_to_XYZ(ADOBE_DNG_XYZ_ILLUMINANT),
chromatic_adaptation_transform)
M_camera_space_to_XYZ = dot_matrix(M_CAT, M_camera_to_XYZ)
else:
uv = UCS_to_uv(XYZ_to_UCS(xy_to_XYZ(xy)))
CCT, _D_uv = uv_to_CCT_Robertson1968(uv)
M_CC = interpolated_matrix(CCT, CCT_calibration_illuminant_1,
CCT_calibration_illuminant_2,
M_camera_calibration_1,
M_camera_calibration_2)
# The reference implementation :cite:`AdobeSystems2015d` diverges from
# the white-paper :cite:`AdobeSystems2012f`:
# The reference implementation directly computes the camera neutral by
# multiplying directly the interpolated colour matrix :math:`CM` with
# the tristimulus values of the *xy* white balance chromaticity
# coordinates.
# The current implementation is based on the white-paper so that the
# interpolated camera calibration matrix :math:`CC` and the
# analog balance matrix :math:`AB` are accounted for.
camera_neutral = xy_to_camera_neutral(
xy, CCT_calibration_illuminant_1, CCT_calibration_illuminant_2,
M_color_matrix_1, M_color_matrix_2, M_camera_calibration_1,
M_camera_calibration_2, analog_balance)
M_AB = np.diagflat(analog_balance)
M_reference_neutral = dot_vector(np.linalg.inv(dot_matrix(M_AB, M_CC)),
camera_neutral)
M_D = np.linalg.inv(np.diagflat(M_reference_neutral))
M_FM = interpolated_matrix(CCT, CCT_calibration_illuminant_1,
CCT_calibration_illuminant_2,
M_forward_matrix_1, M_forward_matrix_2)
M_camera_space_to_XYZ = dot_matrix(
dot_matrix(M_FM, M_D), np.linalg.inv(dot_matrix(M_AB, M_CC)))
return M_camera_space_to_XYZ
def RGB_to_XYZ(RGB,
illuminant_RGB,
illuminant_XYZ,
RGB_to_XYZ_matrix,
chromatic_adaptation_transform='CAT02',
EOCF=None):
"""
Converts from given *RGB* colourspace to *CIE XYZ* tristimulus values.
Parameters
----------
RGB : array_like
*RGB* colourspace array.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* chromaticity coordinates or *CIE xyY*
colourspace array.
illuminant_XYZ : array_like
*CIE XYZ* tristimulus values *illuminant* chromaticity coordinates or
*CIE xyY* colourspace array.
RGB_to_XYZ_matrix : array_like
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
**{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp',
'Fairchild, 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco',
'Bianco PC'}**,
*Chromatic adaptation* transform.
EOCF : object, optional
*Electro-optical conversion function*.
Returns
-------
ndarray
*CIE XYZ* tristimulus values.
Notes
-----
- Input *RGB* colourspace array is in domain [0, 1].
- Input *illuminant_RGB* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Input *illuminant_XYZ* *xy* chromaticity coordinates or *CIE xyY*
colourspace array are in domain [0, :math:`\infty`].
- Output *CIE XYZ* tristimulus values are in domain [0, 1].
Examples
--------
>>> RGB = np.array([0.01103604, 0.12734466, 0.11631037])
>>> illuminant_RGB = np.array([0.31271, 0.32902])
>>> illuminant_XYZ = np.array([0.34567, 0.35850])
>>> chromatic_adaptation_transform = 'Bradford'
>>> RGB_to_XYZ_matrix = np.array([
... [0.41238656, 0.35759149, 0.18045049],
... [0.21263682, 0.71518298, 0.07218020],
... [0.01933062, 0.11919716, 0.95037259]])
>>> RGB_to_XYZ(
... RGB,
... illuminant_RGB,
... illuminant_XYZ,
... RGB_to_XYZ_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.0704953..., 0.1008 , 0.0955831...])
"""
if EOCF is not None:
RGB = EOCF(RGB)
M = chromatic_adaptation_matrix_VonKries(
xyY_to_XYZ(xy_to_xyY(illuminant_RGB)),
xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)),
transform=chromatic_adaptation_transform)
XYZ = dot_vector(RGB_to_XYZ_matrix, RGB)
XYZ_a = dot_vector(M, XYZ)
return XYZ_a
def test_chromatic_adaptation_matrix_VonKries(self):
"""
Tests :func:`colour.adaptation.vonkries.\
chromatic_adaptation_matrix_VonKries` definition.
"""
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.96429568, 1.00000000, 0.82510460])),
np.array([
[1.04257389, 0.03089108, -0.05281257],
[0.02219345, 1.00185663, -0.02107375],
[-0.00116488, -0.00342053, 0.76178907],
]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([1.09846607, 1.00000000, 0.35582280])),
np.array([
[1.17159793, 0.16088780, -0.16158366],
[0.11462057, 0.96182051, -0.06497572],
[-0.00413024, -0.00912739, 0.33871096],
]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.99144661, 1.00000000, 0.67315942])),
np.linalg.inv(
chromatic_adaptation_matrix_VonKries(
np.array([0.99144661, 1.00000000, 0.67315942]),
np.array([0.95045593, 1.00000000, 1.08905775]))),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.96429568, 1.00000000, 0.82510460]),
transform='XYZ Scaling'),
np.array([
[1.01456117, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, 0.75763163],
]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.96429568, 1.00000000, 0.82510460]),
transform='Bradford'),
np.array([
[1.04792979, 0.02294687, -0.05019227],
[0.02962781, 0.99043443, -0.01707380],
[-0.00924304, 0.01505519, 0.75187428],
]),
decimal=7)
np.testing.assert_almost_equal(
chromatic_adaptation_matrix_VonKries(
np.array([0.95045593, 1.00000000, 1.08905775]),
np.array([0.96429568, 1.00000000, 0.82510460]),
transform='Von Kries'),
np.array([
[1.01611856, 0.05535971, -0.05219186],
[0.00608087, 0.99555604, -0.00122642],
[0.00000000, 0.00000000, 0.75763163],
]),
decimal=7)
def XYZ_to_RGB(XYZ,
illuminant_XYZ,
illuminant_RGB,
XYZ_to_RGB_matrix,
chromatic_adaptation_transform='CAT02',
transfer_function=None):
"""
Converts from *CIE XYZ* colourspace to *RGB* colourspace using given
*CIE XYZ* colourspace matrix, *illuminants*, *chromatic adaptation* method,
*normalised primary matrix* and *transfer function*.
Parameters
----------
XYZ : array_like, (3,)
*CIE XYZ* colourspace matrix.
illuminant_XYZ : array_like
*CIE XYZ* colourspace *illuminant* *xy* chromaticity coordinates.
illuminant_RGB : array_like
*RGB* colourspace *illuminant* *xy* chromaticity coordinates.
XYZ_to_RGB_matrix : array_like, (3, 3)
*Normalised primary matrix*.
chromatic_adaptation_transform : unicode, optional
{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp', 'Fairchild,
'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco', 'Bianco PC'},
*Chromatic adaptation* transform.
transfer_function : object, optional
*Transfer function*.
Returns
-------
ndarray, (3,)
*RGB* colourspace matrix.
Notes
-----
- Input *CIE XYZ* colourspace matrix is in domain [0, 1].
- Input *illuminant_XYZ* *xy* chromaticity coordinates are in domain
[0, 1].
- Input *illuminant_RGB* *xy* chromaticity coordinates are in domain
[0, 1].
- Output *RGB* colourspace matrix is in domain [0, 1].
Examples
--------
>>> XYZ = np.array([0.07049534, 0.1008, 0.09558313])
>>> illuminant_XYZ = (0.34567, 0.35850)
>>> illuminant_RGB = (0.31271, 0.32902)
>>> chromatic_adaptation_transform = 'Bradford'
>>> XYZ_to_RGB_matrix = np.array([
... [3.24100326, -1.53739899, -0.49861587],
... [-0.96922426, 1.87592999, 0.04155422],
... [0.05563942, -0.2040112, 1.05714897]])
>>> XYZ_to_RGB(
... XYZ,
... illuminant_XYZ,
... illuminant_RGB,
... XYZ_to_RGB_matrix,
... chromatic_adaptation_transform) # doctest: +ELLIPSIS
array([ 0.0110360..., 0.1273446..., 0.1163103...])
"""
XYZ = np.ravel(XYZ)
cat = chromatic_adaptation_matrix_VonKries(
xy_to_XYZ(illuminant_XYZ),
xy_to_XYZ(illuminant_RGB),
transform=chromatic_adaptation_transform)
XYZ_a = np.dot(cat, XYZ)
RGB = np.dot(XYZ_to_RGB_matrix.reshape((3, 3)),
XYZ_a.reshape((3, 1)))
RGB = np.ravel(RGB)
if transfer_function is not None:
RGB = np.array([transfer_function(x) for x in RGB])
return RGB
