#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Academy Color Encoding System
=============================
Defines the *Academy Color Encoding System* (ACES) related encodings:
- :attr:`ACES_2065_1_COLOURSPACE`
- :attr:`ACES_CC_COLOURSPACE`
- :attr:`ACES_PROXY_COLOURSPACE`
- :attr:`ACES_CG_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] The Academy of Motion Picture Arts and Sciences, Science and
Technology Council, & Academy Color Encoding System (ACES) Project
Subcommittee. (n.d.). Academy Color Encoding System. Retrieved
February 24, 2014, from
http://www.oscars.org/science-technology/council/projects/aces.html
.. [2] The Academy of Motion Picture Arts and Sciences, Science and
Technology Council, & Academy Color Encoding System (ACES) Project
Subcommittee. (2014). Technical Bulletin TB-2014-004 - Informative
Notes on SMPTE ST 2065-1 – Academy Color Encoding Specification
(ACES). Retrieved from
https://github.com/ampas/aces-dev/tree/master/documents
.. [3] The Academy of Motion Picture Arts and Sciences, Science and
Technology Council, & Academy Color Encoding System (ACES) Project
Subcommittee. (2014). Specification S-2014-003 - ACEScc , A
Logarithmic Encoding of ACES Data for use within Color Grading
Systems. Retrieved from
https://github.com/ampas/aces-dev/tree/master/documents
.. [4] The Academy of Motion Picture Arts and Sciences, Science and
Technology Council, & Academy Color Encoding System (ACES) Project
Subcommittee. (2014). Specification S-2013-001 - ACESproxy , an
Integer Log Encoding of ACES Image Data. Retrieved from
https://github.com/ampas/aces-dev/tree/master/documents
.. [5] The Academy of Motion Picture Arts and Sciences, Science and
Technology Council, & Academy Color Encoding System (ACES) Project
Subcommittee. (2014). Technical Bulletin TB-2014-012 - Academy Color
Encoding System Version 1.0 Component Names. Retrieved from
https://github.com/ampas/aces-dev/tree/master/documents
"""
from __future__ import division, unicode_literals
import numpy as np
from colour.colorimetry import ILLUMINANTS
from colour.models import RGB_Colourspace, normalised_primary_matrix
from colour.utilities import CaseInsensitiveMapping, Structure
__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__ = ['AP0',
'AP1',
'ACES_ILLUMINANT',
'ACES_WHITEPOINT',
'AP0_TO_XYZ_MATRIX',
'XYZ_TO_AP0_MATRIX',
'AP1_TO_XYZ_MATRIX',
'XYZ_TO_AP1_MATRIX',
'ACES_2065_1_TRANSFER_FUNCTION',
'ACES_2065_1_INVERSE_TRANSFER_FUNCTION',
'ACES_2065_1_COLOURSPACE',
'ACES_CC_TRANSFER_FUNCTION',
'ACES_CC_INVERSE_TRANSFER_FUNCTION',
'ACES_CC_COLOURSPACE',
'ACES_PROXY_10_CONSTANTS',
'ACES_PROXY_12_CONSTANTS',
'ACES_PROXY_CONSTANTS',
'ACES_PROXY_TRANSFER_FUNCTION',
'ACES_PROXY_INVERSE_TRANSFER_FUNCTION',
'ACES_PROXY_COLOURSPACE',
'ACES_CG_COLOURSPACE']
AP0 = np.array(
[[0.73470, 0.26530],
[0.00000, 1.00000],
[0.00010, -0.07700]])
"""
*ACES Primaries 0* or *AP0* primaries.
AP0 : ndarray, (3, 2)
"""
AP1 = np.array(
[[0.713, 0.293],
[0.165, 0.830],
[0.128, 0.044]])
"""
*ACES Primaries 1* or *AP1* primaries (known as *Rec. 2020+* primaries prior
to *ACES* 1.0 release).
AP1 : ndarray, (3, 2)
"""
ACES_ILLUMINANT = 'D60'
"""
*ACES2065-1* colourspace whitepoint name as illuminant.
ACES_ILLUMINANT : unicode
"""
ACES_WHITEPOINT = ILLUMINANTS.get(
'CIE 1931 2 Degree Standard Observer').get(ACES_ILLUMINANT)
"""
*ACES2065-1* colourspace whitepoint.
ACES_WHITEPOINT : tuple
"""
AP0_TO_XYZ_MATRIX = np.array(
[[9.52552396e-01, 0.00000000e+00, 9.36786317e-05],
[3.43966450e-01, 7.28166097e-01, -7.21325464e-02],
[0.00000000e+00, 0.00000000e+00, 1.00882518e+00]])
"""
*ACES Primaries 0* to *CIE XYZ* tristimulus values matrix.
AP0_TO_XYZ_MATRIX : array_like, (3, 3)
"""
XYZ_TO_AP0_MATRIX = np.linalg.inv(AP0_TO_XYZ_MATRIX)
"""
*CIE XYZ* tristimulus values to *ACES Primaries 0* matrix.
XYZ_TO_AP0_MATRIX : array_like, (3, 3)
"""
AP1_TO_XYZ_MATRIX = normalised_primary_matrix(AP1, ACES_WHITEPOINT)
"""
*ACES Primaries 1* to *CIE XYZ* tristimulus values matrix.
AP1_TO_XYZ_MATRIX : array_like, (3, 3)
"""
XYZ_TO_AP1_MATRIX = np.linalg.inv(AP1_TO_XYZ_MATRIX)
"""
*CIE XYZ* tristimulus values to *ACES Primaries 1* matrix.
XYZ_TO_AP1_MATRIX : array_like, (3, 3)
"""
def _aces_2065_1_transfer_function(value):
"""
Defines the *ACES2065-1* colourspace transfer function.
Parameters
----------
value : numeric or array_like
Value.
Returns
-------
numeric or ndarray
Companded value.
"""
return value
def _aces_2065_1_inverse_transfer_function(value):
"""
Defines the *ACES2065-1* colourspace inverse transfer function.
Parameters
----------
value : numeric or array_like
Value.
Returns
-------
numeric or ndarray
Companded value.
"""
return value
ACES_2065_1_TRANSFER_FUNCTION = _aces_2065_1_transfer_function
"""
Transfer function from linear to *ACES2065-1* colourspace.
ACES_2065_1_TRANSFER_FUNCTION : object
"""
ACES_2065_1_INVERSE_TRANSFER_FUNCTION = _aces_2065_1_inverse_transfer_function
"""
Inverse transfer function from *ACES2065-1* colourspace to linear.
ACES_2065_1_INVERSE_TRANSFER_FUNCTION : object
"""
ACES_2065_1_COLOURSPACE = RGB_Colourspace(
'ACES2065-1',
AP0,
ACES_WHITEPOINT,
ACES_ILLUMINANT,
AP0_TO_XYZ_MATRIX,
XYZ_TO_AP0_MATRIX,
ACES_2065_1_TRANSFER_FUNCTION,
ACES_2065_1_INVERSE_TRANSFER_FUNCTION)
"""
*ACES2065-1* colourspace, base encoding, used for exchange of full fidelity
images and archiving.
ACES_2065_1_COLOURSPACE : RGB_Colourspace
"""
def _aces_cc_transfer_function(value):
"""
Defines the *ACEScc* colourspace transfer function.
Parameters
----------
value : numeric or array_like
Value.
Returns
-------
numeric or ndarray
Companded value.
"""
value = np.asarray(value)
output = np.where(value < 0,
(np.log2(2 ** -15 * 0.5) + 9.72) / 17.52,
(np.log2(2 ** -16 + value * 0.5) + 9.72) / 17.52)
output = np.where(value >= 2 ** -15,
(np.log2(value) + 9.72) / 17.52,
output)
return output
def _aces_cc_inverse_transfer_function(value):
"""
Defines the *ACEScc* colourspace inverse transfer function.
Parameters
----------
value : numeric or array_like
Value.
Returns
-------
numeric or ndarray
Companded value.
"""
value = np.asarray(value)
output = np.where(value < (9.72 - 15) / 17.52,
(2 ** (value * 17.52 - 9.72) - 2 ** -16) * 2,
2 ** (value * 17.52 - 9.72))
output = np.where(value >= (np.log2(65504) + 9.72) / 17.52,
65504,
output)
return output
ACES_CC_TRANSFER_FUNCTION = _aces_cc_transfer_function
"""
Transfer function from linear to *ACEScc* colourspace.
ACES_CC_TRANSFER_FUNCTION : object
"""
ACES_CC_INVERSE_TRANSFER_FUNCTION = (
_aces_cc_inverse_transfer_function)
"""
Inverse transfer function from *ACEScc* colourspace to linear.
ACES_CC_INVERSE_TRANSFER_FUNCTION : object
"""
ACES_CC_COLOURSPACE = RGB_Colourspace(
'ACEScc',
AP1,
ACES_WHITEPOINT,
ACES_ILLUMINANT,
AP1_TO_XYZ_MATRIX,
XYZ_TO_AP1_MATRIX,
ACES_CC_TRANSFER_FUNCTION,
ACES_CC_INVERSE_TRANSFER_FUNCTION)
"""
*ACEScc* colourspace, a working space for color correctors, target for ASC-CDL
values created on-set.
ACES_CC_COLOURSPACE : RGB_Colourspace
"""
ACES_PROXY_10_CONSTANTS = Structure(
CV_min=64,
CV_max=940,
steps_per_stop=50,
mid_CV_offset=425,
mid_log_offset=2.5)
"""
*ACESproxy* 10 bit colourspace constants.
ACES_PROXY_10_CONSTANTS : Structure
"""
ACES_PROXY_12_CONSTANTS = Structure(
CV_min=256,
CV_max=3760,
steps_per_stop=200,
mid_CV_offset=1700,
mid_log_offset=2.5)
"""
*ACESproxy* 12 bit colourspace constants.
ACES_PROXY_12_CONSTANTS : Structure
"""
ACES_PROXY_CONSTANTS = CaseInsensitiveMapping(
{'10 Bit': ACES_PROXY_10_CONSTANTS,
'12 Bit': ACES_PROXY_12_CONSTANTS})
"""
Aggregated *ACESproxy* colourspace constants.
ACES_PROXY_CONSTANTS : CaseInsensitiveMapping
{'10 Bit', '12 Bit'}
"""
def _aces_proxy_transfer_function(value, bit_depth='10 Bit'):
"""
Defines the *ACESproxy* colourspace transfer function.
Parameters
----------
value : numeric or array_like
Value.
bit_depth : unicode, optional
{'10 Bit', '12 Bit'}
*ACESproxy* bit depth.
Returns
-------
numeric or ndarray
Companded value.
"""
value = np.asarray(value)
constants = ACES_PROXY_CONSTANTS.get(bit_depth)
CV_min = np.resize(constants.CV_min, value.shape)
CV_max = np.resize(constants.CV_max, value.shape)
float_2_cv = lambda x: np.maximum(CV_min, np.minimum(CV_max, np.round(x)))
output = np.where(value > 2 ** -9.72,
float_2_cv((np.log2(value) + constants.mid_log_offset) *
constants.steps_per_stop +
constants.mid_CV_offset),
np.resize(CV_min, value.shape))
return output
def _aces_proxy_inverse_transfer_function(value, bit_depth='10 Bit'):
"""
Defines the *ACESproxy* colourspace inverse transfer function.
Parameters
----------
value : numeric or array_like
Value.
bit_depth : unicode, optional
{'10 Bit', '12 Bit'}
*ACESproxy* bit depth.
Returns
-------
numeric or ndarray
Companded value.
"""
value = np.asarray(value)
constants = ACES_PROXY_CONSTANTS.get(bit_depth)
return (2 ** (((value - constants.mid_CV_offset) /
constants.steps_per_stop - constants.mid_log_offset)))
ACES_PROXY_TRANSFER_FUNCTION = _aces_proxy_transfer_function
"""
Transfer function from linear to *ACESproxy* colourspace.
ACES_PROXY_TRANSFER_FUNCTION : object
"""
ACES_PROXY_INVERSE_TRANSFER_FUNCTION = (
_aces_proxy_inverse_transfer_function)
"""
Inverse transfer function from *ACESproxy* colourspace to linear.
ACES_PROXY_INVERSE_TRANSFER_FUNCTION : object
"""
ACES_PROXY_COLOURSPACE = RGB_Colourspace(
'ACESproxy',
AP0,
ACES_WHITEPOINT,
ACES_ILLUMINANT,
AP0_TO_XYZ_MATRIX,
XYZ_TO_AP0_MATRIX,
ACES_PROXY_TRANSFER_FUNCTION,
ACES_PROXY_INVERSE_TRANSFER_FUNCTION)
"""
*ACESproxy* colourspace, a lightweight encoding for transmission over HD-SDI
(or other production transmission schemes), onset look management. Not
intended to be stored or used in production imagery or for final color
grading/mastering.
ACES_PROXY_COLOURSPACE : RGB_Colourspace
"""
ACES_CG_COLOURSPACE = RGB_Colourspace(
'ACEScg',
AP1,
ACES_WHITEPOINT,
ACES_ILLUMINANT,
AP1_TO_XYZ_MATRIX,
XYZ_TO_AP1_MATRIX,
ACES_PROXY_TRANSFER_FUNCTION,
ACES_PROXY_INVERSE_TRANSFER_FUNCTION)
"""
*ACEScg* colourspace, a working space for paint/compositor applications that
don’t support ACES2065-1 or ACEScc.
ACES_CG_COLOURSPACE : RGB_Colourspace
"""
Colour 0.3