#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
SMPTE-C RGB Colourspace
=======================
Defines the *SMPTE-C RGB* colourspace:
- :attr:`SMPTE_C_RGB_COLOURSPACE`.
See Also
--------
`RGB Colourspaces IPython Notebook
<http://nbviewer.ipython.org/github/colour-science/colour-ipython/blob/master/notebooks/models/rgb.ipynb>`_ # noqa
References
----------
.. [1] SMPTE. (2004). SMPTE C Color Monitor Colorimetry. In RP 145:2004
(Vol. RP 145:200). doi:10.5594/S9781614821649
"""
from __future__ import division, unicode_literals
import numpy as np
from colour.colorimetry import ILLUMINANTS
from colour.models import RGB_Colourspace, normalised_primary_matrix
__author__ = 'Colour Developers'
__copyright__ = 'Copyright (C) 2013 - 2015 - Colour Developers'
__license__ = 'New BSD License - http://opensource.org/licenses/BSD-3-Clause'
__maintainer__ = 'Colour Developers'
__email__ = 'colour-science@googlegroups.com'
__status__ = 'Production'
__all__ = ['SMPTE_C_RGB_PRIMARIES',
'SMPTE_C_RGB_ILLUMINANT',
'SMPTE_C_RGB_WHITEPOINT',
'SMPTE_C_RGB_TO_XYZ_MATRIX',
'XYZ_TO_SMPTE_C_RGB_MATRIX',
'SMPTE_C_RGB_TRANSFER_FUNCTION',
'SMPTE_C_RGB_INVERSE_TRANSFER_FUNCTION',
'SMPTE_C_RGB_COLOURSPACE']
SMPTE_C_RGB_PRIMARIES = np.array(
[[0.630, 0.340],
[0.310, 0.595],
[0.155, 0.070]])
"""
*SMPTE-C RGB* colourspace primaries.
SMPTE_C_RGB_PRIMARIES : ndarray, (3, 2)
"""
SMPTE_C_RGB_ILLUMINANT = 'D65'
"""
*SMPTE-C RGB* colourspace whitepoint name as illuminant.
SMPTE_C_RGB_ILLUMINANT : unicode
"""
SMPTE_C_RGB_WHITEPOINT = ILLUMINANTS.get(
'CIE 1931 2 Degree Standard Observer').get(SMPTE_C_RGB_ILLUMINANT)
"""
*SMPTE-C RGB* colourspace whitepoint.
SMPTE_C_RGB_WHITEPOINT : tuple
"""
SMPTE_C_RGB_TO_XYZ_MATRIX = normalised_primary_matrix(
SMPTE_C_RGB_PRIMARIES, SMPTE_C_RGB_WHITEPOINT)
"""
*SMPTE-C RGB* colourspace to *CIE XYZ* colourspace matrix.
SMPTE_C_RGB_TO_XYZ_MATRIX : array_like, (3, 3)
"""
XYZ_TO_SMPTE_C_RGB_MATRIX = np.linalg.inv(SMPTE_C_RGB_TO_XYZ_MATRIX)
"""
*CIE XYZ* colourspace to *SMPTE-C RGB* colourspace matrix.
XYZ_TO_SMPTE_C_RGB_MATRIX : array_like, (3, 3)
"""
def _smpte_c_rgb_transfer_function(value):
"""
Defines the *SMPTE-C RGB* colourspace transfer function.
Parameters
----------
value : numeric
Value.
Returns
-------
numeric
Companded value.
"""
return value ** (1 / 2.2)
def _smpte_c_rgb_inverse_transfer_function(value):
"""
Defines the *SMPTE-C RGB* colourspace inverse transfer
function.
Parameters
----------
value : numeric
Value.
Returns
-------
numeric
Companded value.
"""
return value ** 2.2
SMPTE_C_RGB_TRANSFER_FUNCTION = _smpte_c_rgb_transfer_function
"""
Transfer function from linear to *SMPTE-C RGB* colourspace.
SMPTE_C_RGB_TRANSFER_FUNCTION : object
"""
SMPTE_C_RGB_INVERSE_TRANSFER_FUNCTION = _smpte_c_rgb_inverse_transfer_function
"""
Inverse transfer function from *SMPTE-C RGB* colourspace to linear.
SMPTE_C_RGB_INVERSE_TRANSFER_FUNCTION : object
"""
SMPTE_C_RGB_COLOURSPACE = RGB_Colourspace(
'SMPTE-C RGB',
SMPTE_C_RGB_PRIMARIES,
SMPTE_C_RGB_WHITEPOINT,
SMPTE_C_RGB_ILLUMINANT,
SMPTE_C_RGB_TO_XYZ_MATRIX,
XYZ_TO_SMPTE_C_RGB_MATRIX,
SMPTE_C_RGB_TRANSFER_FUNCTION,
SMPTE_C_RGB_INVERSE_TRANSFER_FUNCTION)
"""
*SMPTE-C RGB* colourspace.
SMPTE_C_RGB_COLOURSPACE : RGB_Colourspace
"""
Colour 0.3