Source code for colour.models.rgb.transfer_functions.cineon

"""
Kodak Cineon Encoding
=====================

Defines the *Kodak Cineon* encoding:

-   :func:`colour.models.log_encoding_Cineon`
-   :func:`colour.models.log_decoding_Cineon`

References
----------
-   :cite:`SonyImageworks2012a` : Sony Imageworks. (2012). make.py. Retrieved
    November 27, 2014, from
    https://github.com/imageworks/OpenColorIO-Configs/blob/master/\
nuke-default/make.py
"""

from __future__ import annotations

import numpy as np

from colour.hints import FloatingOrArrayLike, FloatingOrNDArray
from colour.utilities import (
    as_float,
    as_float_array,
    from_range_1,
    to_domain_1,
)

__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__ = [
    "log_encoding_Cineon",
    "log_decoding_Cineon",
]


[docs]def log_encoding_Cineon( x: FloatingOrArrayLike, black_offset: FloatingOrArrayLike = 10 ** ((95 - 685) / 300), ) -> FloatingOrNDArray: """ Define the *Cineon* log encoding curve / opto-electronic transfer function. Parameters ---------- x Linear data :math:`x`. black_offset Black offset. Returns ------- :class:`numpy.floating` or :class:`numpy.ndarray` Non-linear data :math:`y`. Notes ----- +------------+-----------------------+---------------+ | **Domain** | **Scale - Reference** | **Scale - 1** | +============+=======================+===============+ | ``x`` | [0, 1] | [0, 1] | +------------+-----------------------+---------------+ +------------+-----------------------+---------------+ | **Range** | **Scale - Reference** | **Scale - 1** | +============+=======================+===============+ | ``y`` | [0, 1] | [0, 1] | +------------+-----------------------+---------------+ References ---------- :cite:`SonyImageworks2012a` Examples -------- >>> log_encoding_Cineon(0.18) # doctest: +ELLIPSIS 0.4573196... """ x = to_domain_1(x) black_offset = as_float_array(black_offset) y = (685 + 300 * np.log10(x * (1 - black_offset) + black_offset)) / 1023 return as_float(from_range_1(y))
[docs]def log_decoding_Cineon( y: FloatingOrArrayLike, black_offset: FloatingOrArrayLike = 10 ** ((95 - 685) / 300), ) -> FloatingOrNDArray: """ Define the *Cineon* log decoding curve / electro-optical transfer function. Parameters ---------- y Non-linear data :math:`y`. black_offset Black offset. Returns ------- :class:`numpy.floating` or :class:`numpy.ndarray` Linear data :math:`x`. Notes ----- +------------+-----------------------+---------------+ | **Domain** | **Scale - Reference** | **Scale - 1** | +============+=======================+===============+ | ``y`` | [0, 1] | [0, 1] | +------------+-----------------------+---------------+ +------------+-----------------------+---------------+ | **Range** | **Scale - Reference** | **Scale - 1** | +============+=======================+===============+ | ``x`` | [0, 1] | [0, 1] | +------------+-----------------------+---------------+ References ---------- :cite:`SonyImageworks2012a` Examples -------- >>> log_decoding_Cineon(0.457319613085418) # doctest: +ELLIPSIS 0.1799999... """ y = to_domain_1(y) black_offset = as_float_array(black_offset) x = (10 ** ((1023 * y - 685) / 300) - black_offset) / (1 - black_offset) return as_float(from_range_1(x))