def test_is_identity(self):
"""
Tests :func:`colour.algebra.matrix.is_identity` definition.
"""
self.assertTrue(is_identity(np.array([1, 0, 0, 0, 1, 0, 0, 0, 1]).reshape(3, 3)))
self.assertFalse(is_identity(np.array([1, 2, 0, 0, 1, 0, 0, 0, 1]).reshape(3, 3)))
self.assertTrue(is_identity(np.array([1, 0, 0, 1]).reshape(2, 2), n=2))
self.assertFalse(is_identity(np.array([1, 2, 0, 1]).reshape(2, 2), n=2))
def test_is_identity(self):
"""
Tests :func:`colour.algebra.matrix.is_identity` definition.
"""
self.assertTrue(
is_identity(np.array([1, 0, 0, 0, 1, 0, 0, 0, 1]).reshape(3, 3)))
self.assertFalse(
is_identity(np.array([1, 2, 0, 0, 1, 0, 0, 0, 1]).reshape(3, 3)))
self.assertTrue(is_identity(np.array([1, 0, 0, 1]).reshape(2, 2), n=2))
self.assertFalse(is_identity(np.array([1, 2, 0, 1]).reshape(2, 2),
n=2))
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 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):
"""
Returns the *CIE XYZ* to *Camera Space* 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.
Returns
-------
ndarray
*CIE XYZ* to *Camera Space* 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:`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)
>>> XYZ_to_camera_space_matrix( # doctest: +ELLIPSIS
... np.array([0.34510414, 0.35162252]),
... 2850,
... 6500,
... M_color_matrix_1,
... M_color_matrix_2,
... M_camera_calibration_1,
... M_camera_calibration_2,
... analog_balance)
array([[ 0.4854908..., 0.0408106..., -0.0714282...],
[-0.7433278..., 1.4956549..., 0.2680749...],
[-0.1336946..., 0.1767874..., 0.6654045...]])
"""
M_AB = np.diagflat(analog_balance)
uv = UCS_to_uv(XYZ_to_UCS(xy_to_XYZ(xy)))
CCT, _D_uv = uv_to_CCT_Robertson1968(uv)
if is_identity(M_color_matrix_1) or is_identity(M_color_matrix_2):
M_CM = (M_color_matrix_1
if is_identity(M_color_matrix_2) else M_color_matrix_2)
else:
M_CM = interpolated_matrix(CCT, CCT_calibration_illuminant_1,
CCT_calibration_illuminant_2,
M_color_matrix_1, M_color_matrix_2)
M_CC = interpolated_matrix(CCT, CCT_calibration_illuminant_1,
CCT_calibration_illuminant_2,
M_camera_calibration_1, M_camera_calibration_2)
M_XYZ_to_camera_space = dot_matrix(dot_matrix(M_AB, M_CC), M_CM)
return M_XYZ_to_camera_space