def test_nan_full_to_legal(self):
"""
Tests :func:`colour.models.rgb.transfer_functions.common.full_to_legal`
definition nan support.
"""
full_to_legal(np.array([-1.0, 0.0, 1.0, -np.inf, np.inf, np.nan]), 10)
def test_n_dimensional_full_to_legal(self):
"""
Tests :func:`colour.models.rgb.transfer_functions.common.full_to_legal`
definition n-dimensional arrays support.
"""
CF_f = 1.0
CV_l = 0.918866080156403
np.testing.assert_almost_equal(full_to_legal(CF_f, 10),
CV_l,
decimal=7)
CF_f = np.tile(CF_f, 6)
CV_l = np.tile(CV_l, 6)
np.testing.assert_almost_equal(full_to_legal(CF_f, 10),
CV_l,
decimal=7)
CF_f = np.reshape(CF_f, (2, 3))
CV_l = np.reshape(CV_l, (2, 3))
np.testing.assert_almost_equal(full_to_legal(CF_f, 10),
CV_l,
decimal=7)
CF_f = np.reshape(CF_f, (2, 3, 1))
CV_l = np.reshape(CV_l, (2, 3, 1))
np.testing.assert_almost_equal(full_to_legal(CF_f, 10),
CV_l,
decimal=7)
def test_nan_full_to_legal(self):
"""
Tests :func:`colour.models.rgb.transfer_functions.common.full_to_legal`
definition nan support.
"""
full_to_legal(np.array([-1.0, 0.0, 1.0, -np.inf, np.inf, np.nan]), 10)
def log_decoding_SLog3(y, bit_depth=10, in_legal=True, out_reflection=True):
"""
Defines the *Sony S-Log3* log decoding curve / electro-optical transfer
function.
Parameters
----------
y : numeric or array_like
Non-linear *Sony S-Log3* data :math:`y`.
bit_depth : int, optional
Bit depth used for conversion.
in_legal : bool, optional
Whether the non-linear *Sony S-Log3* data :math:`y` is encoded in legal
range.
out_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
Reflection or :math:`IRE / 100` input light level :math:`x` to a
camera.
References
----------
- :cite:`SonyCorporationd`
Examples
--------
>>> log_decoding_SLog3(0.410557184750733) # doctest: +ELLIPSIS
0.1...
>>> log_decoding_SLog3(0.406392694063927, in_legal=False)
... # doctest: +ELLIPSIS
0.1...
>>> log_decoding_SLog3(0.399507939606216, out_reflection=False)
... # doctest: +ELLIPSIS
0.1...
"""
y = np.asarray(y)
y = y if in_legal else full_to_legal(y, bit_depth)
x = np.where(y >= 171.2102946929 / 1023,
((10**((y * 1023 - 420) / 261.5)) * (0.18 + 0.01) - 0.01),
(y * 1023 - 95) * 0.01125000 / (171.2102946929 - 95))
if not out_reflection:
x = x / 0.9
return as_numeric(x)
def test_n_dimensional_full_to_legal(self):
"""
Tests :func:`colour.models.rgb.transfer_functions.common.full_to_legal`
definition n-dimensional arrays support.
"""
CF_f = 1.0
CV_l = full_to_legal(CF_f, 10)
CF_f = np.tile(CF_f, 6)
CV_l = np.tile(CV_l, 6)
np.testing.assert_almost_equal(
full_to_legal(CF_f, 10), CV_l, decimal=7)
CF_f = np.reshape(CF_f, (2, 3))
CV_l = np.reshape(CV_l, (2, 3))
np.testing.assert_almost_equal(
full_to_legal(CF_f, 10), CV_l, decimal=7)
CF_f = np.reshape(CF_f, (2, 3, 1))
CV_l = np.reshape(CV_l, (2, 3, 1))
np.testing.assert_almost_equal(
full_to_legal(CF_f, 10), CV_l, decimal=7)
def log_encoding_SLog(x, bit_depth=10, out_legal=True, in_reflection=True):
"""
Defines the *Sony S-Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Reflection or :math:`IRE / 100` input light level :math:`x` to a
camera.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the non-linear *Sony S-Log* data :math:`y` is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
Non-linear *Sony S-Log* data :math:`y`.
References
----------
- :cite:`SonyCorporation2012a`
Examples
--------
>>> log_encoding_SLog(0.18) # doctest: +ELLIPSIS
0.3849708...
>>> log_encoding_SLog(0.18, out_legal=False) # doctest: +ELLIPSIS
0.3765127...
>>> log_encoding_SLog(0.18, in_reflection=False) # doctest: +ELLIPSIS
0.3708204...
"""
x = np.asarray(x)
if in_reflection:
x = x / 0.9
y = np.where(x >= 0,
((0.432699 * np.log10(x + 0.037584) + 0.616596) + 0.03),
x * 5 + 0.030001222851889303)
y = full_to_legal(y, bit_depth) if out_legal else y
return as_numeric(y)
def log_decoding_VLog(V_out, bit_depth=10, in_legal=True, out_reflection=True):
"""
Defines the *Panasonic V-Log* log decoding curve / electro-optical transfer
function.
Parameters
----------
V_out : numeric or array_like
Non-linear data :math:`V_{out}`.
bit_depth : int, optional
Bit depth used for conversion.
in_legal : bool, optional
Whether the non-linear *Panasonic V-Log* data :math:`V_{out}` is
encoded in legal range.
out_reflection : bool, optional
Whether the light level :math`L_{in}` to a camera is reflection.
Returns
-------
numeric or ndarray
Linear reflection data :math`L_{in}`.
References
----------
- :cite:`Panasonic2014a`
Examples
--------
>>> log_decoding_VLog(0.423311448760136) # doctest: +ELLIPSIS
0.1799999...
"""
V_out = np.asarray(V_out)
V_out = V_out if in_legal else full_to_legal(V_out, bit_depth)
cut2 = VLOG_CONSTANTS.cut2
b = VLOG_CONSTANTS.b
c = VLOG_CONSTANTS.c
d = VLOG_CONSTANTS.d
L_in = np.where(V_out < cut2, (V_out - 0.125) / 5.6,
np.power(10, ((V_out - d) / c)) - b)
if not out_reflection:
L_in = L_in / 0.9
return as_numeric(L_in)
def log_encoding_CanonLog2(x, bit_depth=10, out_legal=True,
in_reflection=True):
"""
Defines the *Canon Log 2* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the *Canon Log 2* non-linear data is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
*Canon Log 2* non-linear data.
References
----------
- :cite:`Canona`
Examples
--------
>>> log_encoding_CanonLog2(0.18) * 100 # doctest: +ELLIPSIS
39.8254694...
"""
x = np.asarray(x)
if in_reflection:
x = x / 0.9
clog2 = np.where(x < log_decoding_CanonLog2(0.035388128, bit_depth, False),
-(0.281863093 *
(np.log10(-x * 87.09937546 + 1)) - 0.035388128),
0.281863093 * np.log10(x * 87.09937546 + 1) + 0.035388128)
clog2 = full_to_legal(clog2, bit_depth) if out_legal else clog2
return as_numeric(clog2)
def log_encoding_CanonLog(x, bit_depth=10, out_legal=True, in_reflection=True):
"""
Defines the *Canon Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the *Canon Log* non-linear data is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
*Canon Log* non-linear data.
References
----------
- :cite:`Thorpe2012a`
Examples
--------
>>> log_encoding_CanonLog(0.18) * 100 # doctest: +ELLIPSIS
34.3389651...
"""
x = np.asarray(x)
if in_reflection:
x = x / 0.9
clog = np.where(x < log_decoding_CanonLog(0.0730597, bit_depth, False),
-(0.529136 * (np.log10(-x * 10.1596 + 1)) - 0.0730597),
0.529136 * np.log10(10.1596 * x + 1) + 0.0730597)
clog = full_to_legal(clog, bit_depth) if out_legal else clog
return as_numeric(clog)
def test_full_to_legal(self):
"""
Tests :func:`colour.models.rgb.transfer_functions.common.full_to_legal`
definition.
"""
self.assertAlmostEqual(full_to_legal(0.0), 0.062561094819159)
self.assertAlmostEqual(full_to_legal(1.0), 0.918866080156403)
self.assertAlmostEqual(full_to_legal(0.0, out_int=True), 64)
self.assertAlmostEqual(full_to_legal(1.0, out_int=True), 940)
self.assertAlmostEqual(full_to_legal(0, in_int=True),
0.062561094819159)
self.assertAlmostEqual(full_to_legal(1023, in_int=True),
0.918866080156403)
self.assertAlmostEqual(full_to_legal(0, in_int=True, out_int=True), 64)
self.assertAlmostEqual(full_to_legal(1023, in_int=True, out_int=True),
940)
def test_full_to_legal(self):
"""
Tests :func:`colour.models.rgb.transfer_functions.common.full_to_legal`
definition.
"""
self.assertAlmostEqual(full_to_legal(0.0), 0.062561094819159)
self.assertAlmostEqual(full_to_legal(1.0), 0.918866080156403)
self.assertAlmostEqual(full_to_legal(0.0, out_int=True), 64)
self.assertAlmostEqual(full_to_legal(1.0, out_int=True), 940)
self.assertAlmostEqual(
full_to_legal(0, in_int=True), 0.062561094819159)
self.assertAlmostEqual(
full_to_legal(1023, in_int=True), 0.918866080156403)
self.assertAlmostEqual(full_to_legal(0, in_int=True, out_int=True), 64)
self.assertAlmostEqual(
full_to_legal(1023, in_int=True, out_int=True), 940)
def log_decoding_NLog(
out_r: FloatingOrArrayLike,
bit_depth: Integer = 10,
in_normalised_code_value: Boolean = True,
out_reflection: Boolean = True,
constants: Structure = NLOG_CONSTANTS,
) -> FloatingOrNDArray:
"""
Define the *Nikon N-Log* log decoding curve / electro-optical transfer
function.
Parameters
----------
out_r
Non-linear data :math:`out`.
bit_depth
Bit depth used for conversion.
in_normalised_code_value
Whether the non-linear *Nikon N-Log* data :math:`out` is encoded as
normalised code values.
out_reflection
Whether the light level :math`in` to a camera is reflection.
constants
*Nikon N-Log* constants.
Returns
-------
:class:`numpy.floating` or :class:`numpy.ndarray`
Linear reflection data :math`in`.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``out_r`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``in_r`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Nikon2018`
Examples
--------
>>> log_decoding_NLog(0.36366777011713869) # doctest: +ELLIPSIS
0.1799999...
"""
out_r = to_domain_1(out_r)
out_r = (out_r if in_normalised_code_value else full_to_legal(
out_r, bit_depth))
cut2 = constants.cut2
a = constants.a
b = constants.b
c = constants.c
d = constants.d
in_r = np.where(
out_r < cut2,
spow(out_r / a, 3) - b,
np.exp((out_r - d) / c),
)
if not out_reflection:
in_r = in_r / 0.9
return as_float(from_range_1(in_r))
def log_decoding_VLog(V_out,
bit_depth=10,
in_normalised_code_value=True,
out_reflection=True,
constants=VLOG_CONSTANTS,
**kwargs):
"""
Defines the *Panasonic V-Log* log decoding curve / electro-optical transfer
function.
Parameters
----------
V_out : numeric or array_like
Non-linear data :math:`V_{out}`.
bit_depth : int, optional
Bit depth used for conversion.
in_normalised_code_value : bool, optional
Whether the non-linear *Panasonic V-Log* data :math:`V_{out}` is
encoded as normalised code values.
out_reflection : bool, optional
Whether the light level :math`L_{in}` to a camera is reflection.
constants : Structure, optional
*Panasonic V-Log* constants.
Other Parameters
----------------
\\**kwargs : dict, optional
Keywords arguments for deprecation management.
Returns
-------
numeric or ndarray
Linear reflection data :math`L_{in}`.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``V_out`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``L_in`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Panasonic2014a`
Examples
--------
>>> log_decoding_VLog(0.423311448760136) # doctest: +ELLIPSIS
0.1799999...
"""
in_normalised_code_value = handle_arguments_deprecation({
'ArgumentRenamed': [['in_legal', 'in_normalised_code_value']],
}, **kwargs).get('in_normalised_code_value', in_normalised_code_value)
V_out = to_domain_1(V_out)
V_out = (V_out
if in_normalised_code_value else full_to_legal(V_out, bit_depth))
cut2 = constants.cut2
b = constants.b
c = constants.c
d = constants.d
L_in = np.where(
V_out < cut2,
(V_out - 0.125) / 5.6,
10 ** ((V_out - d) / c) - b,
)
if not out_reflection:
L_in = L_in / 0.9
return as_float(from_range_1(L_in))
def log_decoding_VLog(V_out,
bit_depth=10,
in_legal=True,
out_reflection=True,
constants=VLOG_CONSTANTS):
"""
Defines the *Panasonic V-Log* log decoding curve / electro-optical transfer
function.
Parameters
----------
V_out : numeric or array_like
Non-linear data :math:`V_{out}`.
bit_depth : int, optional
Bit depth used for conversion.
in_legal : bool, optional
Whether the non-linear *Panasonic V-Log* data :math:`V_{out}` is
encoded in legal range.
out_reflection : bool, optional
Whether the light level :math`L_{in}` to a camera is reflection.
constants : Structure, optional
*Panasonic V-Log* constants.
Returns
-------
numeric or ndarray
Linear reflection data :math`L_{in}`.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``V_out`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``L_in`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Panasonic2014a`
Examples
--------
>>> log_decoding_VLog(0.423311448760136) # doctest: +ELLIPSIS
0.1799999...
"""
V_out = to_domain_1(V_out)
V_out = V_out if in_legal else full_to_legal(V_out, bit_depth)
cut2 = constants.cut2
b = constants.b
c = constants.c
d = constants.d
L_in = np.where(
V_out < cut2,
(V_out - 0.125) / 5.6,
10 ** ((V_out - d) / c) - b,
)
if not out_reflection:
L_in = L_in / 0.9
return as_float(from_range_1(L_in))
def log_decoding_SLog3(y, bit_depth=10, in_legal=True, out_reflection=True):
"""
Defines the *Sony S-Log3* log decoding curve / electro-optical transfer
function.
Parameters
----------
y : numeric or array_like
Non-linear *Sony S-Log3* data :math:`y`.
bit_depth : int, optional
Bit depth used for conversion.
in_legal : bool, optional
Whether the non-linear *Sony S-Log3* data :math:`y` is encoded in legal
range.
out_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
Reflection or :math:`IRE / 100` input light level :math:`x` to a
camera.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``y`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`SonyCorporationd`
Examples
--------
>>> log_decoding_SLog3(0.410557184750733) # doctest: +ELLIPSIS
0.1...
>>> log_decoding_SLog3(0.406392694063927, in_legal=False)
... # doctest: +ELLIPSIS
0.1...
>>> log_decoding_SLog3(0.399507939606216, out_reflection=False)
... # doctest: +ELLIPSIS
0.1...
"""
y = to_domain_1(y)
y = y if in_legal else full_to_legal(y, bit_depth)
x = np.where(
y >= 171.2102946929 / 1023,
((10 ** ((y * 1023 - 420) / 261.5)) * (0.18 + 0.01) - 0.01),
(y * 1023 - 95) * 0.01125000 / (171.2102946929 - 95),
)
if not out_reflection:
x = x / 0.9
return as_float(from_range_1(x))
def log_encoding_CanonLog(x, bit_depth=10, out_legal=True, in_reflection=True):
"""
Defines the *Canon Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the *Canon Log* non-linear data is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
*Canon Log* non-linear data.
References
----------
:cite:`Thorpe2012a`
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
Examples
--------
>>> log_encoding_CanonLog(0.18) * 100 # doctest: +ELLIPSIS
34.3389651...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale('ignore'):
clog = np.where(
x < log_decoding_CanonLog(0.0730597, bit_depth, False),
-(0.529136 * (np.log10(-x * 10.1596 + 1)) - 0.0730597),
0.529136 * np.log10(10.1596 * x + 1) + 0.0730597,
)
clog = full_to_legal(clog, bit_depth) if out_legal else clog
return as_float(from_range_1(clog))
def log_encoding_CanonLog2(x,
bit_depth=10,
out_legal=True,
in_reflection=True):
"""
Defines the *Canon Log 2* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the *Canon Log 2* non-linear data is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
*Canon Log 2* non-linear data.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog2`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Canona`
Examples
--------
>>> log_encoding_CanonLog2(0.18) * 100 # doctest: +ELLIPSIS
39.8254694...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale('ignore'):
clog2 = np.where(
x < log_decoding_CanonLog2(0.035388128, bit_depth, False),
-(0.281863093 * (np.log10(-x * 87.09937546 + 1)) - 0.035388128),
0.281863093 * np.log10(x * 87.09937546 + 1) + 0.035388128,
)
clog2 = full_to_legal(clog2, bit_depth) if out_legal else clog2
return as_float(from_range_1(clog2))
def log_decoding_VLog(
V_out: FloatingOrArrayLike,
bit_depth: Integer = 10,
in_normalised_code_value: Boolean = True,
out_reflection: Boolean = True,
constants: Structure = CONSTANTS_VLOG,
) -> FloatingOrNDArray:
"""
Define the *Panasonic V-Log* log decoding curve / electro-optical transfer
function.
Parameters
----------
V_out
Non-linear data :math:`V_{out}`.
bit_depth
Bit depth used for conversion.
in_normalised_code_value
Whether the non-linear *Panasonic V-Log* data :math:`V_{out}` is
encoded as normalised code values.
out_reflection
Whether the light level :math`L_{in}` to a camera is reflection.
constants
*Panasonic V-Log* constants.
Returns
-------
:class:`numpy.floating` or :class:`numpy.ndarray`
Linear reflection data :math`L_{in}`.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``V_out`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``L_in`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Panasonic2014a`
Examples
--------
>>> log_decoding_VLog(0.423311448760136) # doctest: +ELLIPSIS
0.1799999...
"""
V_out = to_domain_1(V_out)
V_out = (V_out if in_normalised_code_value else full_to_legal(
V_out, bit_depth))
cut2 = constants.cut2
b = constants.b
c = constants.c
d = constants.d
L_in = np.where(
V_out < cut2,
(V_out - 0.125) / 5.6,
10**((V_out - d) / c) - b,
)
if not out_reflection:
L_in = L_in / 0.9
return as_float(from_range_1(L_in))
def log_decoding_SLog3(
y: FloatingOrArrayLike,
bit_depth: Integer = 10,
in_normalised_code_value: Boolean = True,
out_reflection: Boolean = True,
) -> FloatingOrNDArray:
"""
Define the *Sony S-Log3* log decoding curve / electro-optical transfer
function.
Parameters
----------
y
Non-linear *Sony S-Log3* data :math:`y`.
bit_depth
Bit depth used for conversion.
in_normalised_code_value
Whether the non-linear *Sony S-Log3* data :math:`y` is encoded as
normalised code values.
out_reflection
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
:class:`numpy.floating` or :class:`numpy.ndarray`
Reflection or :math:`IRE / 100` input light level :math:`x` to a
camera.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``y`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`SonyCorporationd`
Examples
--------
>>> log_decoding_SLog3(0.410557184750733) # doctest: +ELLIPSIS
0.1...
"""
y = to_domain_1(y)
y = y if in_normalised_code_value else full_to_legal(y, bit_depth)
x = np.where(
y >= 171.2102946929 / 1023,
((10**((y * 1023 - 420) / 261.5)) * (0.18 + 0.01) - 0.01),
(y * 1023 - 95) * 0.01125000 / (171.2102946929 - 95),
)
if not out_reflection:
x = x / 0.9
return as_float(from_range_1(x))
def log_encoding_SLog(x, bit_depth=10, out_legal=True, in_reflection=True):
"""
Defines the *Sony S-Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Reflection or :math:`IRE / 100` input light level :math:`x` to a
camera.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the non-linear *Sony S-Log* data :math:`y` is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
Non-linear *Sony S-Log* 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:`SonyCorporation2012a`
Examples
--------
>>> log_encoding_SLog(0.18) # doctest: +ELLIPSIS
0.3849708...
>>> log_encoding_SLog(0.18, out_legal=False) # doctest: +ELLIPSIS
0.3765127...
>>> log_encoding_SLog(0.18, in_reflection=False) # doctest: +ELLIPSIS
0.3708204...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
y = np.where(
x >= 0,
((0.432699 * np.log10(x + 0.037584) + 0.616596) + 0.03),
x * 5 + 0.030001222851889303,
)
y = full_to_legal(y, bit_depth) if out_legal else y
return as_float(from_range_1(y))
def log_encoding_CanonLog(x, bit_depth=10, out_legal=True, in_reflection=True):
"""
Defines the *Canon Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the *Canon Log* non-linear data is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
*Canon Log* non-linear data.
References
----------
:cite:`Thorpe2012a`
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
Examples
--------
>>> log_encoding_CanonLog(0.18) * 100 # doctest: +ELLIPSIS
34.3389651...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale('ignore'):
clog = np.where(
x < log_decoding_CanonLog(0.0730597, bit_depth, False),
-(0.529136 * (np.log10(-x * 10.1596 + 1)) - 0.0730597),
0.529136 * np.log10(10.1596 * x + 1) + 0.0730597,
)
clog = full_to_legal(clog, bit_depth) if out_legal else clog
return as_float(from_range_1(clog))
def log_encoding_SLog(x,
bit_depth=10,
out_normalised_code_value=True,
in_reflection=True,
**kwargs):
"""
Defines the *Sony S-Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Reflection or :math:`IRE / 100` input light level :math:`x` to a
camera.
bit_depth : int, optional
Bit depth used for conversion.
out_normalised_code_value : bool, optional
Whether the non-linear *Sony S-Log* data :math:`y` is encoded as
normalised code values.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Other Parameters
----------------
\\**kwargs : dict, optional
Keywords arguments for deprecation management.
Returns
-------
numeric or ndarray
Non-linear *Sony S-Log* 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:`SonyCorporation2012a`
Examples
--------
>>> log_encoding_SLog(0.18) # doctest: +ELLIPSIS
0.3849708...
The values of *IRE and CV of S-Log2 @ISO800* table in
:cite:`SonyCorporation2012a` are obtained as follows:
>>> x = np.array([0, 18, 90]) / 100
>>> np.around(log_encoding_SLog(x, 10, False) * 100).astype(np.int)
array([ 3, 38, 65])
>>> np.around(log_encoding_SLog(x) * (2 ** 10 - 1)).astype(np.int)
array([ 90, 394, 636])
"""
out_normalised_code_value = handle_arguments_deprecation(
{
'ArgumentRenamed': [['out_legal', 'out_normalised_code_value']],
}, **kwargs).get('out_normalised_code_value',
out_normalised_code_value)
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
y = np.where(
x >= 0,
((0.432699 * np.log10(x + 0.037584) + 0.616596) + 0.03),
x * 5 + 0.030001222851889303,
)
y = full_to_legal(y, bit_depth) if out_normalised_code_value else y
return as_float(from_range_1(y))
def log_decoding_FLog(out_r,
bit_depth=10,
in_normalised_code_value=True,
out_reflection=True,
constants=CONSTANTS_FLOG):
"""
Defines the *Fujifilm F-Log* log decoding curve / electro-optical transfer
function.
Parameters
----------
out_r : numeric or array_like
Non-linear data :math:`out`.
bit_depth : int, optional
Bit depth used for conversion.
in_normalised_code_value : bool, optional
Whether the non-linear *Fujifilm F-Log* data :math:`out` is encoded as
normalised code values.
out_reflection : bool, optional
Whether the light level :math`in` to a camera is reflection.
constants : Structure, optional
*Fujifilm F-Log* constants.
Returns
-------
numeric or ndarray
Linear reflection data :math`in`.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``out_r`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``in_r`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Fujifilm2016`
Examples
--------
>>> log_decoding_FLog(0.45931845866162124) # doctest: +ELLIPSIS
0.1800000...
"""
out_r = to_domain_1(out_r)
out_r = (out_r if in_normalised_code_value else full_to_legal(
out_r, bit_depth))
cut2 = constants.cut2
a = constants.a
b = constants.b
c = constants.c
d = constants.d
e = constants.e
f = constants.f
in_r = np.where(
out_r < cut2,
(out_r - f) / e,
(10**((out_r - d) / c)) / a - b / a,
)
if not out_reflection:
in_r = in_r / 0.9
return as_float(from_range_1(in_r))
def log_encoding_CanonLog3(
x: FloatingOrArrayLike,
bit_depth: Integer = 10,
out_normalised_code_value: Boolean = True,
in_reflection: Boolean = True,
) -> FloatingOrNDArray:
"""
Define the *Canon Log 3* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x
Linear data :math:`x`.
bit_depth
Bit depth used for conversion.
out_normalised_code_value
Whether the *Canon Log 3* non-linear data is encoded as normalised code
values.
in_reflection
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
:class:`numpy.floating` or :class:`numpy.ndarray`
*Canon Log 3* non-linear data.
Notes
-----
- Introspection of the grafting points by Shaw, N. (2018) shows that the
*Canon Log 3* IDT was likely derived from its encoding curve as the
later is grafted at *+/-0.014*::
>>> clog3 = 0.04076162
>>> (clog3 - 0.073059361) / 2.3069815
-0.014000000000000002
>>> clog3 = 0.105357102
>>> (clog3 - 0.073059361) / 2.3069815
0.013999999999999997
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog3`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Canona`
Examples
--------
>>> log_encoding_CanonLog3(0.18) * 100 # doctest: +ELLIPSIS
34.3389369...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale("ignore"):
clog3 = np.select(
(
x < log_decoding_CanonLog3(0.04076162, bit_depth, False,
False),
x <= log_decoding_CanonLog3(0.105357102, bit_depth, False,
False),
x > log_decoding_CanonLog3(0.105357102, bit_depth, False,
False),
),
(
-0.42889912 * np.log10(-x * 14.98325 + 1) + 0.07623209,
2.3069815 * x + 0.073059361,
0.42889912 * np.log10(x * 14.98325 + 1) + 0.069886632,
),
)
clog3_cv = (full_to_legal(clog3, bit_depth)
if out_normalised_code_value else clog3)
return as_float(from_range_1(clog3_cv))
def log_encoding_CanonLog3(x,
bit_depth=10,
out_legal=True,
in_reflection=True):
"""
Defines the *Canon Log 3* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the *Canon Log 3* non-linear data is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
*Canon Log 3* non-linear data.
Notes
-----
- Introspection of the grafting points by Shaw, N. (2018) shows that the
*Canon Log 3* IDT was likely derived from its encoding curve as the
later is grafted at *+/-0.014*::
>>> clog3 = 0.04076162
>>> (clog3 - 0.073059361) / 2.3069815
-0.014000000000000002
>>> clog3 = 0.105357102
>>> (clog3 - 0.073059361) / 2.3069815
0.013999999999999997
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog3`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Canona`
Examples
--------
>>> log_encoding_CanonLog3(0.18) * 100 # doctest: +ELLIPSIS
34.3389369...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale('ignore'):
clog3 = np.select(
(x < log_decoding_CanonLog3(0.04076162, bit_depth, False, False),
x <= log_decoding_CanonLog3(0.105357102, bit_depth, False, False),
x > log_decoding_CanonLog3(0.105357102, bit_depth, False, False)),
(-0.42889912 * np.log10(-x * 14.98325 + 1) + 0.07623209,
2.3069815 * x + 0.073059361,
0.42889912 * np.log10(x * 14.98325 + 1) + 0.069886632))
clog3 = full_to_legal(clog3, bit_depth) if out_legal else clog3
return as_float(from_range_1(clog3))
def log_encoding_CanonLog3(x, bit_depth=10, out_legal=True,
in_reflection=True):
"""
Defines the *Canon Log 3* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the *Canon Log 3* non-linear data is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
*Canon Log 3* non-linear data.
Notes
-----
- Introspection of the grafting points by Shaw, N. (2018) shows that the
*Canon Log 3* IDT was likely derived from its encoding curve as the
later is grafted at *+/-0.014*::
>>> clog3 = 0.04076162
>>> (clog3 - 0.073059361) / 2.3069815
-0.014000000000000002
>>> clog3 = 0.105357102
>>> (clog3 - 0.073059361) / 2.3069815
0.013999999999999997
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog3`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Canona`
Examples
--------
>>> log_encoding_CanonLog3(0.18) * 100 # doctest: +ELLIPSIS
34.3389369...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale('ignore'):
clog3 = np.select(
(x < log_decoding_CanonLog3(0.04076162, bit_depth, False, False),
x <= log_decoding_CanonLog3(0.105357102, bit_depth, False, False),
x > log_decoding_CanonLog3(0.105357102, bit_depth, False, False)),
(-0.42889912 * np.log10(-x * 14.98325 + 1) + 0.07623209,
2.3069815 * x + 0.073059361,
0.42889912 * np.log10(x * 14.98325 + 1) + 0.069886632))
clog3 = full_to_legal(clog3, bit_depth) if out_legal else clog3
return as_float(from_range_1(clog3))
def log_encoding_CanonLog2(x,
bit_depth=10,
out_normalised_code_value=True,
in_reflection=True,
**kwargs):
"""
Defines the *Canon Log 2* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_normalised_code_value : bool, optional
Whether the *Canon Log 2* non-linear data is encoded as normalised
code values.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Other Parameters
----------------
\\**kwargs : dict, optional
Keywords arguments for deprecation management.
Returns
-------
numeric or ndarray
*Canon Log 2* non-linear data.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog2`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Canona`
Examples
--------
>>> log_encoding_CanonLog2(0.18) * 100 # doctest: +ELLIPSIS
39.8254694...
"""
out_normalised_code_value = handle_arguments_deprecation(
{
'ArgumentRenamed': [['out_legal', 'out_normalised_code_value']],
}, **kwargs).get('out_normalised_code_value',
out_normalised_code_value)
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale('ignore'):
clog2 = np.where(
x < log_decoding_CanonLog2(0.035388128, bit_depth, False),
-(0.281863093 * (np.log10(-x * 87.09937546 + 1)) - 0.035388128),
0.281863093 * np.log10(x * 87.09937546 + 1) + 0.035388128,
)
clog2 = (full_to_legal(clog2, bit_depth)
if out_normalised_code_value else clog2)
return as_float(from_range_1(clog2))
def log_encoding_SLog(
x: FloatingOrArrayLike,
bit_depth: Integer = 10,
out_normalised_code_value: Boolean = True,
in_reflection: Boolean = True,
) -> FloatingOrNDArray:
"""
Define the *Sony S-Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x
Reflection or :math:`IRE / 100` input light level :math:`x` to a
camera.
bit_depth
Bit depth used for conversion.
out_normalised_code_value
Whether the non-linear *Sony S-Log* data :math:`y` is encoded as
normalised code values.
in_reflection
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
:class:`numpy.floating` or :class:`numpy.ndarray`
Non-linear *Sony S-Log* 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:`SonyCorporation2012a`
Examples
--------
>>> log_encoding_SLog(0.18) # doctest: +ELLIPSIS
0.3849708...
The values of *IRE and CV of S-Log2 @ISO800* table in
:cite:`SonyCorporation2012a` are obtained as follows:
>>> x = np.array([0, 18, 90]) / 100
>>> np.around(log_encoding_SLog(x, 10, False) * 100).astype(np.int)
array([ 3, 38, 65])
>>> np.around(log_encoding_SLog(x) * (2 ** 10 - 1)).astype(np.int)
array([ 90, 394, 636])
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
y = np.where(
x >= 0,
((0.432699 * np.log10(x + 0.037584) + 0.616596) + 0.03),
x * 5 + 0.030001222851889303,
)
y_cv = full_to_legal(y, bit_depth) if out_normalised_code_value else y
return as_float(from_range_1(y_cv))
def log_decoding_SLog3(y,
bit_depth=10,
in_normalised_code_value=True,
out_reflection=True,
**kwargs):
"""
Defines the *Sony S-Log3* log decoding curve / electro-optical transfer
function.
Parameters
----------
y : numeric or array_like
Non-linear *Sony S-Log3* data :math:`y`.
bit_depth : int, optional
Bit depth used for conversion.
in_normalised_code_value : bool, optional
Whether the non-linear *Sony S-Log3* data :math:`y` is encoded as
normalised code values.
out_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Other Parameters
----------------
\\**kwargs : dict, optional
Keywords arguments for deprecation management.
Returns
-------
numeric or ndarray
Reflection or :math:`IRE / 100` input light level :math:`x` to a
camera.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``y`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`SonyCorporationd`
Examples
--------
>>> log_decoding_SLog3(0.410557184750733) # doctest: +ELLIPSIS
0.1...
"""
in_normalised_code_value = handle_arguments_deprecation(
{
'ArgumentRenamed': [['in_legal', 'in_normalised_code_value']],
}, **kwargs).get('in_normalised_code_value', in_normalised_code_value)
y = to_domain_1(y)
y = y if in_normalised_code_value else full_to_legal(y, bit_depth)
x = np.where(
y >= 171.2102946929 / 1023,
((10**((y * 1023 - 420) / 261.5)) * (0.18 + 0.01) - 0.01),
(y * 1023 - 95) * 0.01125000 / (171.2102946929 - 95),
)
if not out_reflection:
x = x / 0.9
return as_float(from_range_1(x))
def log_encoding_CanonLog(x,
bit_depth=10,
out_normalised_code_value=True,
in_reflection=True,
**kwargs):
"""
Defines the *Canon Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_normalised_code_value : bool, optional
Whether the *Canon Log* non-linear data is encoded as normalised code
values.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Other Parameters
----------------
\\**kwargs : dict, optional
Keywords arguments for deprecation management.
Returns
-------
numeric or ndarray
*Canon Log* non-linear data.
References
----------
:cite:`Thorpe2012a`
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
Examples
--------
>>> log_encoding_CanonLog(0.18) * 100 # doctest: +ELLIPSIS
34.3389651...
The values of *Table 2 Canon-Log Code Values* table in :cite:`Thorpe2012a`
are obtained as follows:
>>> x = np.array([0, 2, 18, 90, 720]) / 100
>>> np.around(log_encoding_CanonLog(x) * (2 ** 10 - 1)).astype(np.int)
array([ 128, 169, 351, 614, 1016])
>>> np.around(log_encoding_CanonLog(x, 10, False) * 100, 1)
array([ 7.3, 12. , 32.8, 62.7, 108.7])
"""
out_normalised_code_value = handle_arguments_deprecation(
{
'ArgumentRenamed': [['out_legal', 'out_normalised_code_value']],
}, **kwargs).get('out_normalised_code_value',
out_normalised_code_value)
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale('ignore'):
clog = np.where(
x < log_decoding_CanonLog(0.0730597, bit_depth, False),
-(0.529136 * (np.log10(-x * 10.1596 + 1)) - 0.0730597),
0.529136 * np.log10(10.1596 * x + 1) + 0.0730597,
)
clog = (full_to_legal(clog, bit_depth)
if out_normalised_code_value else clog)
return as_float(from_range_1(clog))
def log_encoding_CanonLog2(
x: FloatingOrArrayLike,
bit_depth: Integer = 10,
out_normalised_code_value: Boolean = True,
in_reflection: Boolean = True,
) -> FloatingOrNDArray:
"""
Define the *Canon Log 2* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x
Linear data :math:`x`.
bit_depth
Bit depth used for conversion.
out_normalised_code_value
Whether the *Canon Log 2* non-linear data is encoded as normalised
code values.
in_reflection
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
:class:`numpy.floating` or :class:`numpy.ndarray`
*Canon Log 2* non-linear data.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog2`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Canona`
Examples
--------
>>> log_encoding_CanonLog2(0.18) * 100 # doctest: +ELLIPSIS
39.8254694...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale("ignore"):
clog2 = np.where(
x < log_decoding_CanonLog2(0.035388128, bit_depth, False),
-(0.281863093 * (np.log10(-x * 87.09937546 + 1)) - 0.035388128),
0.281863093 * np.log10(x * 87.09937546 + 1) + 0.035388128,
)
clog2_cv = (full_to_legal(clog2, bit_depth)
if out_normalised_code_value else clog2)
return as_float(from_range_1(clog2_cv))
def log_decoding_VLog(V_out,
bit_depth=10,
in_legal=True,
out_reflection=True,
constants=VLOG_CONSTANTS):
"""
Defines the *Panasonic V-Log* log decoding curve / electro-optical transfer
function.
Parameters
----------
V_out : numeric or array_like
Non-linear data :math:`V_{out}`.
bit_depth : int, optional
Bit depth used for conversion.
in_legal : bool, optional
Whether the non-linear *Panasonic V-Log* data :math:`V_{out}` is
encoded in legal range.
out_reflection : bool, optional
Whether the light level :math`L_{in}` to a camera is reflection.
constants : Structure, optional
*Panasonic V-Log* constants.
Returns
-------
numeric or ndarray
Linear reflection data :math`L_{in}`.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``V_out`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``L_in`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Panasonic2014a`
Examples
--------
>>> log_decoding_VLog(0.423311448760136) # doctest: +ELLIPSIS
0.1799999...
"""
V_out = to_domain_1(V_out)
V_out = V_out if in_legal else full_to_legal(V_out, bit_depth)
cut2 = constants.cut2
b = constants.b
c = constants.c
d = constants.d
L_in = np.where(
V_out < cut2,
(V_out - 0.125) / 5.6,
10**((V_out - d) / c) - b,
)
if not out_reflection:
L_in = L_in / 0.9
return as_float(from_range_1(L_in))
def log_encoding_CanonLog(
x: FloatingOrArrayLike,
bit_depth: Integer = 10,
out_normalised_code_value: Boolean = True,
in_reflection: Boolean = True,
) -> FloatingOrNDArray:
"""
Define the *Canon Log* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x
Linear data :math:`x`.
bit_depth
Bit depth used for conversion.
out_normalised_code_value
Whether the *Canon Log* non-linear data is encoded as normalised code
values.
in_reflection
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
:class:`numpy.floating` or :class:`numpy.ndarray`
*Canon Log* non-linear data.
References
----------
:cite:`Thorpe2012a`
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
Examples
--------
>>> log_encoding_CanonLog(0.18) * 100 # doctest: +ELLIPSIS
34.3389651...
The values of *Table 2 Canon-Log Code Values* table in :cite:`Thorpe2012a`
are obtained as follows:
>>> x = np.array([0, 2, 18, 90, 720]) / 100
>>> np.around(log_encoding_CanonLog(x) * (2 ** 10 - 1)).astype(np.int)
array([ 128, 169, 351, 614, 1016])
>>> np.around(log_encoding_CanonLog(x, 10, False) * 100, 1)
array([ 7.3, 12. , 32.8, 62.7, 108.7])
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale("ignore"):
clog = np.where(
x < log_decoding_CanonLog(0.0730597, bit_depth, False),
-(0.529136 * (np.log10(-x * 10.1596 + 1)) - 0.0730597),
0.529136 * np.log10(10.1596 * x + 1) + 0.0730597,
)
clog_cv = (full_to_legal(clog, bit_depth)
if out_normalised_code_value else clog)
return as_float(from_range_1(clog_cv))
def log_encoding_CanonLog2(x, bit_depth=10, out_legal=True,
in_reflection=True):
"""
Defines the *Canon Log 2* log encoding curve / opto-electronic transfer
function.
Parameters
----------
x : numeric or array_like
Linear data :math:`x`.
bit_depth : int, optional
Bit depth used for conversion.
out_legal : bool, optional
Whether the *Canon Log 2* non-linear data is encoded in legal
range.
in_reflection : bool, optional
Whether the light level :math:`x` to a camera is reflection.
Returns
-------
numeric or ndarray
*Canon Log 2* non-linear data.
Notes
-----
+------------+-----------------------+---------------+
| **Domain** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``x`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
+------------+-----------------------+---------------+
| **Range** | **Scale - Reference** | **Scale - 1** |
+============+=======================+===============+
| ``clog2`` | [0, 1] | [0, 1] |
+------------+-----------------------+---------------+
References
----------
:cite:`Canona`
Examples
--------
>>> log_encoding_CanonLog2(0.18) * 100 # doctest: +ELLIPSIS
39.8254694...
"""
x = to_domain_1(x)
if in_reflection:
x = x / 0.9
with domain_range_scale('ignore'):
clog2 = np.where(
x < log_decoding_CanonLog2(0.035388128, bit_depth, False),
-(0.281863093 * (np.log10(-x * 87.09937546 + 1)) - 0.035388128),
0.281863093 * np.log10(x * 87.09937546 + 1) + 0.035388128,
)
clog2 = full_to_legal(clog2, bit_depth) if out_legal else clog2
return as_float(from_range_1(clog2))