# -*- coding: utf-8 -*-
"""
Digital Cinema Distribution Master (DCDM)
=========================================
Defines the *DCDM* opto-electrical transfer function (OETF / OECF) and
electro-optical transfer function (EOTF / EOCF):
- :func:`colour.models.eotf_reverse_DCDM`
- :func:`colour.models.eotf_DCDM`
See Also
--------
`RGB Colourspaces Jupyter Notebook
<http://nbviewer.jupyter.org/github/colour-science/colour-notebooks/\
blob/master/notebooks/models/rgb.ipynb>`_
References
----------
- :cite:`DigitalCinemaInitiatives2007b` : Digital Cinema Initiatives. (2007).
Digital Cinema System Specification - Version 1.1. Retrieved from
http://www.dcimovies.com/archives/spec_v1_1/\
DCI_DCinema_System_Spec_v1_1.pdf
"""
from __future__ import division, unicode_literals
import numpy as np
from colour.algebra import spow
from colour.constants import DEFAULT_INT_DTYPE
from colour.utilities import from_range_1, to_domain_1
__author__ = 'Colour Developers'
__copyright__ = 'Copyright (C) 2013-2019 - Colour Developers'
__license__ = 'New BSD License - http://opensource.org/licenses/BSD-3-Clause'
__maintainer__ = 'Colour Developers'
__email__ = 'colour-science@googlegroups.com'
__status__ = 'Production'
__all__ = ['eotf_reverse_DCDM', 'eotf_DCDM']
[docs]def eotf_reverse_DCDM(XYZ, out_int=False):
"""
Defines the *DCDM* reverse electro-optical transfer function (EOTF / EOCF).
Parameters
----------
XYZ : numeric or array_like
*CIE XYZ* tristimulus values.
out_int : bool, optional
Whether to return value as integer code value or float equivalent of a
code value at a given bit depth.
Returns
-------
numeric or ndarray
Non-linear *CIE XYZ'* tristimulus values.
Notes
-----
+----------------+-----------------------+---------------+
| **Domain \\*** | **Scale - Reference** | **Scale - 1** |
+================+=======================+===============+
| ``XYZ`` | [0, 1] | [0, 1] |
+----------------+-----------------------+---------------+
+----------------+-----------------------+---------------+
| **Range \\*** | **Scale - Reference** | **Scale - 1** |
+================+=======================+===============+
| ``XYZ_p`` | [0, 1] | [0, 1] |
+----------------+-----------------------+---------------+
- \\* This definition has an output integer switch, thus the domain-range
scale information is only given for the floating point mode.
References
----------
:cite:`DigitalCinemaInitiatives2007b`
Examples
--------
>>> eotf_reverse_DCDM(0.18) # doctest: +ELLIPSIS
0.1128186...
>>> eotf_reverse_DCDM(0.18, out_int=True)
462
"""
XYZ = to_domain_1(XYZ)
XYZ_p = spow(XYZ / 52.37, 1 / 2.6)
if out_int:
return np.round(4095 * XYZ_p).astype(DEFAULT_INT_DTYPE)
else:
return from_range_1(XYZ_p)
[docs]def eotf_DCDM(XYZ_p, in_int=False):
"""
Defines the *DCDM* electro-optical transfer function (EOTF / EOCF).
Parameters
----------
XYZ_p : numeric or array_like
Non-linear *CIE XYZ'* tristimulus values.
in_int : bool, optional
Whether to treat the input value as integer code value or float
equivalent of a code value at a given bit depth.
Returns
-------
numeric or ndarray
*CIE XYZ* tristimulus values.
Notes
-----
+----------------+-----------------------+---------------+
| **Domain \\*** | **Scale - Reference** | **Scale - 1** |
+================+=======================+===============+
| ``XYZ_p`` | [0, 1] | [0, 1] |
+----------------+-----------------------+---------------+
+----------------+-----------------------+---------------+
| **Range \\*** | **Scale - Reference** | **Scale - 1** |
+================+=======================+===============+
| ``XYZ`` | [0, 1] | [0, 1] |
+----------------+-----------------------+---------------+
- \\* This definition has an input integer switch, thus the domain-range
scale information is only given for the floating point mode.
References
----------
:cite:`DigitalCinemaInitiatives2007b`
Examples
--------
>>> eotf_DCDM(0.11281860951766724) # doctest: +ELLIPSIS
0.18...
>>> eotf_DCDM(462, in_int=True) # doctest: +ELLIPSIS
0.18...
"""
XYZ_p = to_domain_1(XYZ_p)
if in_int:
XYZ_p = XYZ_p / 4095
XYZ = 52.37 * spow(XYZ_p, 2.6)
return from_range_1(XYZ)