Source code for colour.models.rgb.rgb_colourspace

"""
RGB Colourspace and Transformations
===================================

Defines the :class:`colour.RGB_Colourspace` class for the *RGB* colourspaces
datasets from :mod:`colour.models.datasets.aces_rgb`, etc... and the following
*RGB* colourspace transformations or helper definitions:

-   :func:`colour.XYZ_to_RGB`
-   :func:`colour.RGB_to_XYZ`
-   :func:`colour.matrix_RGB_to_RGB`
-   :func:`colour.RGB_to_RGB`

References
----------
-   :cite:`InternationalElectrotechnicalCommission1999a` : International
    Electrotechnical Commission. (1999). IEC 61966-2-1:1999 - Multimedia
    systems and equipment - Colour measurement and management - Part 2-1:
    Colour management - Default RGB colour space - sRGB (p. 51).
    https://webstore.iec.ch/publication/6169
-   :cite:`Panasonic2014a` : Panasonic. (2014). VARICAM V-Log/V-Gamut (pp.
    1-7).
    http://pro-av.panasonic.net/en/varicam/common/pdf/VARICAM_V-Log_V-Gamut.pdf
"""

from __future__ import annotations

import numpy as np
from copy import deepcopy

from colour.adaptation import matrix_chromatic_adaptation_VonKries
from colour.algebra import matrix_dot, vector_dot
from colour.hints import (
    Any,
    ArrayLike,
    Boolean,
    Callable,
    Literal,
    NDArray,
    Optional,
    Union,
    cast,
)
from colour.models import xy_to_XYZ, xy_to_xyY, xyY_to_XYZ
from colour.models.rgb import (
    chromatically_adapted_primaries,
    normalised_primary_matrix,
)
from colour.utilities import (
    as_float_array,
    attest,
    domain_range_scale,
    filter_kwargs,
    from_range_1,
    multiline_str,
    multiline_repr,
    optional,
    to_domain_1,
    is_string,
)

__author__ = "Colour Developers"
__copyright__ = "Copyright 2013 Colour Developers"
__license__ = "New BSD License - https://opensource.org/licenses/BSD-3-Clause"
__maintainer__ = "Colour Developers"
__email__ = "colour-developers@colour-science.org"
__status__ = "Production"

__all__ = [
    "RGB_Colourspace",
    "XYZ_to_RGB",
    "RGB_to_XYZ",
    "matrix_RGB_to_RGB",
    "RGB_to_RGB",
]


[docs]class RGB_Colourspace: """ Implement support for the *RGB* colourspaces datasets from :mod:`colour.models.datasets.aces_rgb`, etc.... Colour science literature related to *RGB* colourspaces and encodings defines their dataset using different degree of precision or rounding. While instances where a whitepoint is being defined with a value different than its canonical agreed one are rare, it is however very common to have normalised primary matrices rounded at different decimals. This can yield large discrepancies in computations. Such an occurrence is the *V-Gamut* colourspace white paper, that defines the *V-Gamut* to *ITU-R BT.709* conversion matrix as follows:: [[ 1.806576 -0.695697 -0.110879] [-0.170090 1.305955 -0.135865] [-0.025206 -0.154468 1.179674]] Computing this matrix using *ITU-R BT.709* colourspace derived normalised primary matrix yields:: [[ 1.8065736 -0.6956981 -0.1108786] [-0.1700890 1.3059548 -0.1358648] [-0.0252057 -0.1544678 1.1796737]] The latter matrix is almost equals with the former, however performing the same computation using *IEC 61966-2-1:1999* *sRGB* colourspace normalised primary matrix introduces severe disparities:: [[ 1.8063853 -0.6956147 -0.1109453] [-0.1699311 1.3058387 -0.1358616] [-0.0251630 -0.1544899 1.1797117]] In order to provide support for both literature defined dataset and accurate computations enabling transformations without loss of precision, the :class:`colour.RGB_Colourspace` class provides two sets of transformation matrices: - Instantiation transformation matrices - Derived transformation matrices Upon instantiation, the :class:`colour.RGB_Colourspace` class stores the given ``matrix_RGB_to_XYZ`` and ``matrix_XYZ_to_RGB`` arguments and also computes their derived counterpart using the ``primaries`` and ``whitepoint`` arguments. Whether the initialisation or derived matrices are used in subsequent computations is dependent on the :attr:`colour.RGB_Colourspace.use_derived_matrix_RGB_to_XYZ` and :attr:`colour.RGB_Colourspace.use_derived_matrix_XYZ_to_RGB` attribute values. Parameters ---------- name *RGB* colourspace name. primaries *RGB* colourspace primaries. whitepoint *RGB* colourspace whitepoint. whitepoint_name *RGB* colourspace whitepoint name. matrix_RGB_to_XYZ Transformation matrix from colourspace to *CIE XYZ* tristimulus values. matrix_XYZ_to_RGB Transformation matrix from *CIE XYZ* tristimulus values to colourspace. cctf_encoding Encoding colour component transfer function (Encoding CCTF) / opto-electronic transfer function (OETF) that maps estimated tristimulus values in a scene to :math:`R'G'B'` video component signal value. cctf_decoding Decoding colour component transfer function (Decoding CCTF) / electro-optical transfer function (EOTF) that maps an :math:`R'G'B'` video component signal value to tristimulus values at the display. use_derived_matrix_RGB_to_XYZ Whether to use the instantiation time normalised primary matrix or to use a computed derived normalised primary matrix. use_derived_matrix_XYZ_to_RGB Whether to use the instantiation time inverse normalised primary matrix or to use a computed derived inverse normalised primary matrix. Attributes ---------- - :attr:`~colour.RGB_Colourspace.name` - :attr:`~colour.RGB_Colourspace.primaries` - :attr:`~colour.RGB_Colourspace.whitepoint` - :attr:`~colour.RGB_Colourspace.whitepoint_name` - :attr:`~colour.RGB_Colourspace.matrix_RGB_to_XYZ` - :attr:`~colour.RGB_Colourspace.matrix_XYZ_to_RGB` - :attr:`~colour.RGB_Colourspace.cctf_encoding` - :attr:`~colour.RGB_Colourspace.cctf_decoding` - :attr:`~colour.RGB_Colourspace.use_derived_matrix_RGB_to_XYZ` - :attr:`~colour.RGB_Colourspace.use_derived_matrix_XYZ_to_RGB` Methods ------- - :attr:`~colour.RGB_Colourspace.__init__` - :attr:`~colour.RGB_Colourspace.__str__` - :attr:`~colour.RGB_Colourspace.__repr__` - :attr:`~colour.RGB_Colourspace.use_derived_transformation_matrices` - :attr:`~colour.RGB_Colourspace.chromatically_adapt` - :attr:`~colour.RGB_Colourspace.copy` Notes ----- - The normalised primary matrix defined by :attr:`colour.RGB_Colourspace.matrix_RGB_to_XYZ` property is treated as the prime matrix from which the inverse will be calculated as required by the internal derivation mechanism. This behaviour has been chosen in accordance with literature where commonly a *RGB* colourspace is defined by its normalised primary matrix as it is directly computed from the chosen primaries and whitepoint. References ---------- :cite:`InternationalElectrotechnicalCommission1999a`, :cite:`Panasonic2014a` Examples -------- >>> p = np.array([0.73470, 0.26530, 0.00000, 1.00000, 0.00010, -0.07700]) >>> whitepoint = np.array([0.32168, 0.33767]) >>> matrix_RGB_to_XYZ = np.identity(3) >>> matrix_XYZ_to_RGB = np.identity(3) >>> colourspace = RGB_Colourspace('RGB Colourspace', p, whitepoint, 'ACES', ... matrix_RGB_to_XYZ, matrix_XYZ_to_RGB) >>> colourspace.matrix_RGB_to_XYZ array([[ 1., 0., 0.], [ 0., 1., 0.], [ 0., 0., 1.]]) >>> colourspace.matrix_XYZ_to_RGB array([[ 1., 0., 0.], [ 0., 1., 0.], [ 0., 0., 1.]]) >>> colourspace.use_derived_transformation_matrices(True) >>> colourspace.matrix_RGB_to_XYZ # doctest: +ELLIPSIS array([[ 9.5255239...e-01, 0.0000000...e+00, 9.3678631...e-05], [ 3.4396645...e-01, 7.2816609...e-01, -7.2132546...e-02], [ 0.0000000...e+00, 0.0000000...e+00, 1.0088251...e+00]]) >>> colourspace.matrix_XYZ_to_RGB # doctest: +ELLIPSIS array([[ 1.0498110...e+00, 0.0000000...e+00, -9.7484540...e-05], [ -4.9590302...e-01, 1.3733130...e+00, 9.8240036...e-02], [ 0.0000000...e+00, 0.0000000...e+00, 9.9125201...e-01]]) >>> colourspace.use_derived_matrix_RGB_to_XYZ = False >>> colourspace.matrix_RGB_to_XYZ array([[ 1., 0., 0.], [ 0., 1., 0.], [ 0., 0., 1.]]) >>> colourspace.use_derived_matrix_XYZ_to_RGB = False >>> colourspace.matrix_XYZ_to_RGB array([[ 1., 0., 0.], [ 0., 1., 0.], [ 0., 0., 1.]]) """
[docs] def __init__( self, name: str, primaries: ArrayLike, whitepoint: ArrayLike, whitepoint_name: Optional[str] = None, matrix_RGB_to_XYZ: Optional[ArrayLike] = None, matrix_XYZ_to_RGB: Optional[ArrayLike] = None, cctf_encoding: Optional[Callable] = None, cctf_decoding: Optional[Callable] = None, use_derived_matrix_RGB_to_XYZ: Boolean = False, use_derived_matrix_XYZ_to_RGB: Boolean = False, ): self._derived_matrix_RGB_to_XYZ: NDArray = np.array([]) self._derived_matrix_XYZ_to_RGB: NDArray = np.array([]) self._name: str = f"{self.__class__.__name__} ({id(self)})" self.name = name self._primaries: NDArray = np.array([]) self.primaries = primaries # type: ignore[assignment] self._whitepoint: NDArray = np.array([]) self.whitepoint = whitepoint # type: ignore[assignment] self._whitepoint_name: Optional[str] = None self.whitepoint_name = whitepoint_name self._matrix_RGB_to_XYZ: Optional[NDArray] = None self.matrix_RGB_to_XYZ = matrix_RGB_to_XYZ # type: ignore[assignment] self._matrix_XYZ_to_RGB: Optional[NDArray] = None self.matrix_XYZ_to_RGB = matrix_XYZ_to_RGB # type: ignore[assignment] self._cctf_encoding: Optional[Callable] = None self.cctf_encoding = cctf_encoding self._cctf_decoding: Optional[Callable] = None self.cctf_decoding = cctf_decoding self._use_derived_matrix_RGB_to_XYZ: Boolean = False self.use_derived_matrix_RGB_to_XYZ = use_derived_matrix_RGB_to_XYZ self._use_derived_matrix_XYZ_to_RGB: Boolean = False self.use_derived_matrix_XYZ_to_RGB = use_derived_matrix_XYZ_to_RGB
@property def name(self) -> str: """ Getter and setter property for the name. Parameters ---------- value Value to set the name with. Returns ------- :class:`str` *RGB* colourspace name. """ return self._name @name.setter def name(self, value: str): """Setter for the **self.name** property.""" attest( is_string(value), f'"name" property: "{value}" type is not "str"!', ) self._name = value @property def primaries(self) -> NDArray: """ Getter and setter property for the primaries. Parameters ---------- value Value to set the primaries with. Returns ------- :class:`numpy.ndarray` *RGB* colourspace primaries. """ return self._primaries @primaries.setter def primaries(self, value: ArrayLike): """Setter for the **self.primaries** property.""" attest( isinstance(value, (tuple, list, np.ndarray, np.matrix)), f'"matrix_XYZ_to_RGB" property: "{value!r}" is not a "tuple", ' f'"list", "ndarray" or "matrix" instance!', ) value = as_float_array(value) value = np.reshape(value, (3, 2)) self._primaries = value self._derive_transformation_matrices() @property def whitepoint(self) -> NDArray: """ Getter and setter property for the whitepoint. Parameters ---------- value Value to set the whitepoint with. Returns ------- :class:`numpy.ndarray` *RGB* colourspace whitepoint. """ return self._whitepoint @whitepoint.setter def whitepoint(self, value: ArrayLike): """Setter for the **self.whitepoint** property.""" attest( isinstance(value, (tuple, list, np.ndarray, np.matrix)), f'"matrix_XYZ_to_RGB" property: "{value!r}" is not a "tuple", ' f'"list", "ndarray" or "matrix" instance!', ) value = as_float_array(value) self._whitepoint = value self._derive_transformation_matrices() @property def whitepoint_name(self) -> Optional[str]: """ Getter and setter property for the whitepoint_name. Parameters ---------- value Value to set the whitepoint_name with. Returns ------- :py:data:`None` or :class:`str` *RGB* colourspace whitepoint name. """ return self._whitepoint_name @whitepoint_name.setter def whitepoint_name(self, value: Optional[str]): """Setter for the **self.whitepoint_name** property.""" if value is not None: attest( is_string(value), f'"whitepoint_name" property: "{value}" type is not "str"!', ) self._whitepoint_name = value @property def matrix_RGB_to_XYZ(self) -> NDArray: """ Getter and setter property for the transformation matrix from colourspace to *CIE XYZ* tristimulus values. Parameters ---------- value Transformation matrix from colourspace to *CIE XYZ* tristimulus values. Returns ------- :class:`numpy.ndarray` Transformation matrix from colourspace to *CIE XYZ* tristimulus values. """ if ( self._matrix_RGB_to_XYZ is None or self._use_derived_matrix_RGB_to_XYZ ): return self._derived_matrix_RGB_to_XYZ else: return self._matrix_RGB_to_XYZ @matrix_RGB_to_XYZ.setter def matrix_RGB_to_XYZ(self, value: Optional[ArrayLike]): """Setter for the **self.matrix_RGB_to_XYZ** property.""" if value is not None: attest( isinstance(value, (tuple, list, np.ndarray, np.matrix)), f'"matrix_RGB_to_XYZ" property: "{value!r}" is not a "tuple", ' f'"list", "ndarray" or "matrix" instance!', ) value = as_float_array(value) self._matrix_RGB_to_XYZ = value @property def matrix_XYZ_to_RGB(self) -> NDArray: """ Getter and setter property for the transformation matrix from *CIE XYZ* tristimulus values to colourspace. Parameters ---------- value Transformation matrix from *CIE XYZ* tristimulus values to colourspace. Returns ------- :class:`numpy.ndarray` Transformation matrix from *CIE XYZ* tristimulus values to colourspace. """ if ( self._matrix_XYZ_to_RGB is None or self._use_derived_matrix_XYZ_to_RGB ): return self._derived_matrix_XYZ_to_RGB else: return self._matrix_XYZ_to_RGB @matrix_XYZ_to_RGB.setter def matrix_XYZ_to_RGB(self, value: Optional[ArrayLike]): """Setter for the **self.matrix_XYZ_to_RGB** property.""" if value is not None: attest( isinstance(value, (tuple, list, np.ndarray, np.matrix)), f'"matrix_XYZ_to_RGB" property: "{value!r}" is not a "tuple", ' f'"list", "ndarray" or "matrix" instance!', ) value = as_float_array(value) self._matrix_XYZ_to_RGB = value @property def cctf_encoding(self) -> Optional[Callable]: """ Getter and setter property for the encoding colour component transfer function (Encoding CCTF) / opto-electronic transfer function (OETF). Parameters ---------- value Encoding colour component transfer function (Encoding CCTF) / opto-electronic transfer function (OETF). Returns ------- :py:data:`None` or Callable Encoding colour component transfer function (Encoding CCTF) / opto-electronic transfer function (OETF). """ return self._cctf_encoding @cctf_encoding.setter def cctf_encoding(self, value: Optional[Callable]): """Setter for the **self.cctf_encoding** property.""" if value is not None: attest( hasattr(value, "__call__"), f'"cctf_encoding" property: "{value}" is not callable!', ) self._cctf_encoding = value @property def cctf_decoding(self) -> Optional[Callable]: """ Getter and setter property for the decoding colour component transfer function (Decoding CCTF) / electro-optical transfer function (EOTF). Parameters ---------- value Decoding colour component transfer function (Decoding CCTF) / electro-optical transfer function (EOTF). Returns ------- :py:data:`None` or Callable Decoding colour component transfer function (Decoding CCTF) / electro-optical transfer function (EOTF). """ return self._cctf_decoding @cctf_decoding.setter def cctf_decoding(self, value: Optional[Callable]): """Setter for the **self.cctf_decoding** property.""" if value is not None: attest( hasattr(value, "__call__"), f'"cctf_decoding" property: "{value}" is not callable!', ) self._cctf_decoding = value @property def use_derived_matrix_RGB_to_XYZ(self) -> Boolean: """ Getter and setter property for whether to use the instantiation time normalised primary matrix or to use a computed derived normalised primary matrix. Parameters ---------- value Whether to use the instantiation time normalised primary matrix or to use a computed derived normalised primary matrix. Returns ------- :class:`bool` Whether to use the instantiation time normalised primary matrix or to use a computed derived normalised primary matrix. """ return self._use_derived_matrix_RGB_to_XYZ @use_derived_matrix_RGB_to_XYZ.setter def use_derived_matrix_RGB_to_XYZ(self, value: Boolean): """Setter for the **self.use_derived_matrix_RGB_to_XYZ** property.""" attest( isinstance(value, (bool, np.bool_)), f'"use_derived_matrix_RGB_to_XYZ" property: "{value}" is not a ' f'"bool"!', ) self._use_derived_matrix_RGB_to_XYZ = value @property def use_derived_matrix_XYZ_to_RGB(self) -> Boolean: """ Getter and setter property for Whether to use the instantiation time inverse normalised primary matrix or to use a computed derived inverse normalised primary matrix. Parameters ---------- value Whether to use the instantiation time inverse normalised primary matrix or to use a computed derived inverse normalised primary matrix. Returns ------- :class:`bool` Whether to use the instantiation time inverse normalised primary matrix or to use a computed derived inverse normalised primary matrix. """ return self._use_derived_matrix_XYZ_to_RGB @use_derived_matrix_XYZ_to_RGB.setter def use_derived_matrix_XYZ_to_RGB(self, value: Boolean): """Setter for the **self.use_derived_matrix_XYZ_to_RGB** property.""" attest( isinstance(value, (bool, np.bool_)), f'"use_derived_matrix_XYZ_to_RGB" property: "{value}" is not a ' f'"bool"!', ) self._use_derived_matrix_XYZ_to_RGB = value
[docs] def __str__(self) -> str: """ Return a formatted string representation of the *RGB* colourspace. Returns ------- :class:`str` Formatted string representation. Examples -------- >>> p = np.array( ... [0.73470, 0.26530, 0.00000, 1.00000, 0.00010, -0.07700]) >>> whitepoint = np.array([0.32168, 0.33767]) >>> matrix_RGB_to_XYZ = np.identity(3) >>> matrix_XYZ_to_RGB = np.identity(3) >>> cctf_encoding = lambda x: x >>> cctf_decoding = lambda x: x >>> print(RGB_Colourspace('RGB Colourspace', p, whitepoint, 'ACES', ... matrix_RGB_to_XYZ, matrix_XYZ_to_RGB, ... cctf_encoding, cctf_decoding)) ... # doctest: +ELLIPSIS RGB Colourspace --------------- <BLANKLINE> Primaries : [[ 7.34700000e-01 2.65300000e-01] [ 0.00000000e+00 1.00000000e+00] [ 1.00000000e-04 -7.70000000e-02]] Whitepoint : [ 0.32168 0.33767] Whitepoint Name : ACES Encoding CCTF : <function <lambda> at 0x...> Decoding CCTF : <function <lambda> at 0x...> NPM : [[ 1. 0. 0.] [ 0. 1. 0.] [ 0. 0. 1.]] NPM -1 : [[ 1. 0. 0.] [ 0. 1. 0.] [ 0. 0. 1.]] Derived NPM : \ [[ 9.5255239...e-01 0.0000000...e+00 9.3678631...e-05] \ [ 3.4396645...e-01 7.2816609...e-01 -7.2132546...e-02] \ [ 0.0000000...e+00 0.0000000...e+00 1.0088251...e+00]] Derived NPM -1 : \ [[ 1.0498110...e+00 0.0000000...e+00 -9.7484540...e-05] \ [ -4.9590302...e-01 1.3733130...e+00 9.8240036...e-02] \ [ 0.0000000...e+00 0.0000000...e+00 9.9125201...e-01]] Use Derived NPM : False Use Derived NPM -1 : False """ return multiline_str( self, [ {"name": "name", "section": True}, {"line_break": True}, {"name": "primaries", "label": "Primaries"}, {"name": "whitepoint", "label": "Whitepoint"}, {"name": "whitepoint_name", "label": "Whitepoint Name"}, {"name": "cctf_encoding", "label": "Encoding CCTF"}, {"name": "cctf_decoding", "label": "Decoding CCTF"}, {"name": "_matrix_RGB_to_XYZ", "label": "NPM"}, {"name": "_matrix_XYZ_to_RGB", "label": "NPM -1"}, { "name": "_derived_matrix_RGB_to_XYZ", "label": "Derived NPM", }, { "name": "_derived_matrix_XYZ_to_RGB", "label": "Derived NPM -1", }, { "name": "use_derived_matrix_RGB_to_XYZ", "label": "Use Derived NPM", }, { "name": "use_derived_matrix_XYZ_to_RGB", "label": "Use Derived NPM -1", }, ], )
[docs] def __repr__(self) -> str: """ Return an (almost) evaluable string representation of the *RGB* colourspace. Returns ------- :class`str` (Almost) evaluable string representation. Examples -------- >>> from colour.models import linear_function >>> p = np.array( ... [0.73470, 0.26530, 0.00000, 1.00000, 0.00010, -0.07700]) >>> whitepoint = np.array([0.32168, 0.33767]) >>> matrix_RGB_to_XYZ = np.identity(3) >>> matrix_XYZ_to_RGB = np.identity(3) >>> RGB_Colourspace('RGB Colourspace', p, whitepoint, 'ACES', ... matrix_RGB_to_XYZ, matrix_XYZ_to_RGB, ... linear_function, linear_function) ... # doctest: +ELLIPSIS RGB_Colourspace('RGB Colourspace', [[ 7.34700000e-01, 2.65300000e-01], [ 0.00000000e+00, 1.00000000e+00], [ 1.00000000e-04, -7.70000000e-02]], [ 0.32168, 0.33767], 'ACES', [[ 1., 0., 0.], [ 0., 1., 0.], [ 0., 0., 1.]], [[ 1., 0., 0.], [ 0., 1., 0.], [ 0., 0., 1.]], linear_function, linear_function, False, False) """ return multiline_repr( self, [ {"name": "name"}, {"name": "primaries"}, {"name": "whitepoint"}, {"name": "whitepoint_name"}, {"name": "matrix_RGB_to_XYZ"}, {"name": "matrix_XYZ_to_RGB"}, { "name": "cctf_encoding", "formatter": lambda x: ( None if self.cctf_encoding is None else self.cctf_encoding.__name__ if hasattr(self.cctf_encoding, "__name__") else str(self.cctf_encoding) ), }, { "name": "cctf_decoding", "formatter": lambda x: ( None if self.cctf_decoding is None else self.cctf_decoding.__name__ if hasattr(self.cctf_decoding, "__name__") else str(self.cctf_decoding) ), }, {"name": "use_derived_matrix_RGB_to_XYZ"}, {"name": "use_derived_matrix_XYZ_to_RGB"}, ], )
def _derive_transformation_matrices(self): """ Compute the derived transformations matrices, the normalised primary matrix and its inverse. """ if hasattr(self, "_primaries") and hasattr(self, "_whitepoint"): if self._primaries is not None and self._whitepoint is not None: npm = normalised_primary_matrix( self._primaries, self._whitepoint ) self._derived_matrix_RGB_to_XYZ = npm self._derived_matrix_XYZ_to_RGB = np.linalg.inv(npm)
[docs] def use_derived_transformation_matrices(self, usage: Boolean = True): """ Enable or disables usage of both derived transformations matrices, the normalised primary matrix and its inverse in subsequent computations. Parameters ---------- usage Whether to use the derived transformations matrices. """ self.use_derived_matrix_RGB_to_XYZ = usage self.use_derived_matrix_XYZ_to_RGB = usage
[docs] def chromatically_adapt( self, whitepoint: ArrayLike, whitepoint_name: Optional[str] = None, chromatic_adaptation_transform: Union[ Literal[ "Bianco 2010", "Bianco PC 2010", "Bradford", "CAT02 Brill 2008", "CAT02", "CAT16", "CMCCAT2000", "CMCCAT97", "Fairchild", "Sharp", "Von Kries", "XYZ Scaling", ], str, ] = "CAT02", ) -> RGB_Colourspace: """ Chromatically adapt the *RGB* colourspace *primaries* :math:`xy` chromaticity coordinates from *RGB* colourspace whitepoint to reference ``whitepoint``. Parameters ---------- whitepoint Reference illuminant / whitepoint :math:`xy` chromaticity coordinates. whitepoint_name Reference illuminant / whitepoint name. chromatic_adaptation_transform *Chromatic adaptation* transform. Returns ------- :class:`colour.RGB_Colourspace` Chromatically adapted *RGB* colourspace. Examples -------- >>> p = np.array( ... [0.73470, 0.26530, 0.00000, 1.00000, 0.00010, -0.07700]) >>> w_t = np.array([0.32168, 0.33767]) >>> w_r = np.array([0.31270, 0.32900]) >>> colourspace = RGB_Colourspace('RGB Colourspace', p, w_t, 'D65') >>> print(colourspace.chromatically_adapt(w_r, 'D50', 'Bradford')) ... # doctest: +ELLIPSIS RGB Colourspace - Chromatically Adapted to 'D50' ------------------------------------------------ <BLANKLINE> Primaries : [[ 0.73485524 0.26422533] [-0.00617091 1.01131496] [ 0.01596756 -0.0642355 ]] Whitepoint : [ 0.3127 0.329 ] Whitepoint Name : D50 Encoding CCTF : None Decoding CCTF : None NPM : None NPM -1 : None Derived NPM : [[ 0.93827985 -0.00445145 0.01662752] [ 0.33736889 0.72952157 -0.06689046] [ 0.00117395 -0.00371071 1.09159451]] Derived NPM -1 : [[ 1.06349549 0.00640891 -0.01580679] [-0.49207413 1.36822341 0.09133709] [-0.00281646 0.00464417 0.91641857]] Use Derived NPM : True Use Derived NPM -1 : True """ colourspace = self.copy() colourspace.primaries = chromatically_adapted_primaries( colourspace.primaries, colourspace.whitepoint, whitepoint, chromatic_adaptation_transform, ) colourspace.whitepoint = whitepoint # type: ignore[assignment] colourspace.whitepoint_name = whitepoint_name colourspace._matrix_RGB_to_XYZ = None colourspace._matrix_XYZ_to_RGB = None colourspace._derive_transformation_matrices() colourspace.use_derived_transformation_matrices() colourspace.name = ( f"{colourspace.name} - Chromatically Adapted to " f"{cast(str, optional(whitepoint_name, whitepoint))!r}" ) return colourspace
[docs] def copy(self) -> RGB_Colourspace: """ Return a copy of the *RGB* colourspace. Returns ------- :class:`colour.RGB_Colourspace` *RGB* colourspace copy. """ return deepcopy(self)
[docs]def XYZ_to_RGB( XYZ: ArrayLike, illuminant_XYZ: ArrayLike, illuminant_RGB: ArrayLike, matrix_XYZ_to_RGB: ArrayLike, chromatic_adaptation_transform: Optional[ Union[ Literal[ "Bianco 2010", "Bianco PC 2010", "Bradford", "CAT02 Brill 2008", "CAT02", "CAT16", "CMCCAT2000", "CMCCAT97", "Fairchild", "Sharp", "Von Kries", "XYZ Scaling", ], str, ] ] = "CAT02", cctf_encoding: Optional[Callable] = None, ) -> NDArray: """ Convert from *CIE XYZ* tristimulus values to *RGB* colourspace array. Parameters ---------- XYZ *CIE XYZ* tristimulus values. illuminant_XYZ *CIE xy* chromaticity coordinates or *CIE xyY* colourspace array of the *illuminant* for the input *CIE XYZ* tristimulus values. illuminant_RGB *CIE xy* chromaticity coordinates or *CIE xyY* colourspace array of the *illuminant* for the output *RGB* colourspace array. matrix_XYZ_to_RGB Matrix converting the *CIE XYZ* tristimulus values to *RGB* colourspace array, i.e. the inverse *Normalised Primary Matrix* (NPM). chromatic_adaptation_transform *Chromatic adaptation* transform, if *None* no chromatic adaptation is performed. cctf_encoding Encoding colour component transfer function (Encoding CCTF) or opto-electronic transfer function (OETF). Returns ------- :class:`numpy.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' >>> matrix_XYZ_to_RGB = 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, matrix_XYZ_to_RGB, ... 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 = matrix_chromatic_adaptation_VonKries( xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)), xyY_to_XYZ(xy_to_xyY(illuminant_RGB)), transform=chromatic_adaptation_transform, ) XYZ = vector_dot(M_CAT, XYZ) RGB = vector_dot(matrix_XYZ_to_RGB, XYZ) if cctf_encoding is not None: with domain_range_scale("ignore"): RGB = cctf_encoding(RGB) return from_range_1(RGB)
[docs]def RGB_to_XYZ( RGB: ArrayLike, illuminant_RGB: ArrayLike, illuminant_XYZ: ArrayLike, matrix_RGB_to_XYZ: ArrayLike, chromatic_adaptation_transform: Optional[ Union[ Literal[ "Bianco 2010", "Bianco PC 2010", "Bradford", "CAT02 Brill 2008", "CAT02", "CAT16", "CMCCAT2000", "CMCCAT97", "Fairchild", "Sharp", "Von Kries", "XYZ Scaling", ], str, ] ] = "CAT02", cctf_decoding: Optional[Callable] = None, ) -> NDArray: """ Convert given *RGB* colourspace array to *CIE XYZ* tristimulus values. Parameters ---------- RGB *RGB* colourspace array. illuminant_RGB *CIE xy* chromaticity coordinates or *CIE xyY* colourspace array of the *illuminant* for the input *RGB* colourspace array. illuminant_XYZ *CIE xy* chromaticity coordinates or *CIE xyY* colourspace array of the *illuminant* for the output *CIE XYZ* tristimulus values. matrix_RGB_to_XYZ Matrix converting the *RGB* colourspace array to *CIE XYZ* tristimulus values, i.e. the *Normalised Primary Matrix* (NPM). chromatic_adaptation_transform *Chromatic adaptation* transform, if *None* no chromatic adaptation is performed. cctf_decoding Decoding colour component transfer function (Decoding CCTF) or electro-optical transfer function (EOTF). Returns ------- :class:`numpy.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' >>> matrix_RGB_to_XYZ = 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, matrix_RGB_to_XYZ, ... chromatic_adaptation_transform) # doctest: +ELLIPSIS array([ 0.2163881..., 0.1257 , 0.0384749...]) """ RGB = to_domain_1(RGB) if cctf_decoding is not None: with domain_range_scale("ignore"): RGB = cctf_decoding(RGB) XYZ = vector_dot(matrix_RGB_to_XYZ, RGB) if chromatic_adaptation_transform is not None: M_CAT = matrix_chromatic_adaptation_VonKries( xyY_to_XYZ(xy_to_xyY(illuminant_RGB)), xyY_to_XYZ(xy_to_xyY(illuminant_XYZ)), transform=chromatic_adaptation_transform, ) XYZ = vector_dot(M_CAT, XYZ) return from_range_1(XYZ)
[docs]def matrix_RGB_to_RGB( input_colourspace: RGB_Colourspace, output_colourspace: RGB_Colourspace, chromatic_adaptation_transform: Optional[ Union[ Literal[ "Bianco 2010", "Bianco PC 2010", "Bradford", "CAT02 Brill 2008", "CAT02", "CAT16", "CMCCAT2000", "CMCCAT97", "Fairchild", "Sharp", "Von Kries", "XYZ Scaling", ], str, ] ] = "CAT02", ) -> NDArray: """ Compute the matrix :math:`M` converting from given input *RGB* colourspace to output *RGB* colourspace using given *chromatic adaptation* method. Parameters ---------- input_colourspace *RGB* input colourspace. output_colourspace *RGB* output colourspace. chromatic_adaptation_transform *Chromatic adaptation* transform, if *None* no chromatic adaptation is performed. Returns ------- :class:`numpy.ndarray` Conversion matrix :math:`M`. Examples -------- >>> from colour.models import ( ... RGB_COLOURSPACE_sRGB, RGB_COLOURSPACE_PROPHOTO_RGB) >>> matrix_RGB_to_RGB(RGB_COLOURSPACE_sRGB, RGB_COLOURSPACE_PROPHOTO_RGB) ... # doctest: +ELLIPSIS array([[ 0.5288241..., 0.3340609..., 0.1373616...], [ 0.0975294..., 0.8790074..., 0.0233981...], [ 0.0163599..., 0.1066124..., 0.8772485...]]) """ M = input_colourspace.matrix_RGB_to_XYZ if chromatic_adaptation_transform is not None: M_CAT = matrix_chromatic_adaptation_VonKries( xy_to_XYZ(input_colourspace.whitepoint), xy_to_XYZ(output_colourspace.whitepoint), chromatic_adaptation_transform, ) M = matrix_dot(M_CAT, input_colourspace.matrix_RGB_to_XYZ) M = matrix_dot(output_colourspace.matrix_XYZ_to_RGB, M) return M
[docs]def RGB_to_RGB( RGB: ArrayLike, input_colourspace: RGB_Colourspace, output_colourspace: RGB_Colourspace, chromatic_adaptation_transform: Optional[ Union[ Literal[ "Bianco 2010", "Bianco PC 2010", "Bradford", "CAT02 Brill 2008", "CAT02", "CAT16", "CMCCAT2000", "CMCCAT97", "Fairchild", "Sharp", "Von Kries", "XYZ Scaling", ], str, ] ] = "CAT02", apply_cctf_decoding: Boolean = False, apply_cctf_encoding: Boolean = False, **kwargs: Any, ) -> NDArray: """ Convert given *RGB* colourspace array from given input *RGB* colourspace to output *RGB* colourspace using given *chromatic adaptation* method. Parameters ---------- RGB *RGB* colourspace array. input_colourspace *RGB* input colourspace. output_colourspace *RGB* output colourspace. chromatic_adaptation_transform *Chromatic adaptation* transform, if *None* no chromatic adaptation is performed. apply_cctf_decoding Apply input colourspace decoding colour component transfer function / electro-optical transfer function. apply_cctf_encoding Apply output colourspace encoding colour component transfer function / opto-electronic transfer function. Other Parameters ---------------- kwargs Keywords arguments for the colour component transfer functions. Returns ------- :class:`numpy.ndarray` *RGB* colourspace array. Notes ----- +--------------------+-----------------------+---------------+ | **Domain** | **Scale - Reference** | **Scale - 1** | +====================+=======================+===============+ | ``RGB`` | [0, 1] | [0, 1] | +--------------------+-----------------------+---------------+ +--------------------+-----------------------+---------------+ | **Range** | **Scale - Reference** | **Scale - 1** | +====================+=======================+===============+ | ``RGB`` | [0, 1] | [0, 1] | +--------------------+-----------------------+---------------+ Examples -------- >>> from colour.models import ( ... RGB_COLOURSPACE_sRGB, RGB_COLOURSPACE_PROPHOTO_RGB) >>> RGB = np.array([0.45595571, 0.03039702, 0.04087245]) >>> RGB_to_RGB(RGB, RGB_COLOURSPACE_sRGB, RGB_COLOURSPACE_PROPHOTO_RGB) ... # doctest: +ELLIPSIS array([ 0.2568891..., 0.0721446..., 0.0465553...]) """ RGB = to_domain_1(RGB) if apply_cctf_decoding and input_colourspace.cctf_decoding is not None: with domain_range_scale("ignore"): RGB = input_colourspace.cctf_decoding( RGB, **filter_kwargs(input_colourspace.cctf_decoding, **kwargs) ) M = matrix_RGB_to_RGB( input_colourspace, output_colourspace, chromatic_adaptation_transform ) RGB = vector_dot(M, RGB) if apply_cctf_encoding and output_colourspace.cctf_encoding is not None: with domain_range_scale("ignore"): RGB = output_colourspace.cctf_encoding( RGB, **filter_kwargs(output_colourspace.cctf_encoding, **kwargs), ) return from_range_1(RGB)