Pillow/docs/reference/ImageCms.rst

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.. py:module:: PIL.ImageCms
.. py:currentmodule:: PIL.ImageCms
:py:mod:`ImageCms` Module
=========================
The :py:mod:`ImageCms` module provides color profile management
support using the LittleCMS2 color management engine, based on Kevin
Cazabon's PyCMS library.
.. automodule:: PIL.ImageCms
:members:
:noindex:
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CmsProfile
----------
The ICC color profiles are wrapped in an instance of the class
:py:class:`CmsProfile`. The specification ICC.1:2010 contains more
information about the meaning of the values in ICC profiles.
For convenience, all XYZ-values are also given as xyY-values (so they
can be easily displayed in a chromaticity diagram, for example).
.. py:class:: CmsProfile
.. py:attribute:: creation_date
Date and time this profile was first created (see 7.2.1 of ICC.1:2010).
:type: :py:class:`datetime.datetime` or ``None``
.. py:attribute:: version
The version number of the ICC standard that this profile follows
(e.g. `2.0`).
:type: :py:class:`float`
.. py:attribute:: icc_version
Same as `version`, but in encoded format (see 7.2.4 of ICC.1:2010).
.. py:attribute:: device_class
4-character string identifying the profile class. One of
``scnr``, ``mntr``, ``prtr``, ``link``, ``spac``, ``abst``,
``nmcl`` (see 7.2.5 of ICC.1:2010 for details).
:type: :py:class:`string`
.. py:attribute:: xcolor_space
4-character string (padded with whitespace) identifying the color
space, e.g. ``XYZ␣``, ``RGB␣`` or ``CMYK`` (see 7.2.6 of
ICC.1:2010 for details).
Note that the deprecated attribute ``color_space`` contains an
interpreted (non-padded) variant of this (but can be empty on
unknown input).
:type: :py:class:`string`
.. py:attribute:: connection_space
4-character string (padded with whitespace) identifying the color
space on the B-side of the transform (see 7.2.7 of ICC.1:2010 for
details).
Note that the deprecated attribute ``pcs`` contains an interpreted
(non-padded) variant of this (but can be empty on unknown input).
:type: :py:class:`string`
.. py:attribute:: header_flags
The encoded header flags of the profile (see 7.2.11 of ICC.1:2010
for details).
:type: :py:class:`int`
.. py:attribute:: header_manufacturer
4-character string (padded with whitespace) identifying the device
manufacturer, which shall match the signature contained in the
appropriate section of the ICC signature registry found at
www.color.org (see 7.2.12 of ICC.1:2010).
:type: :py:class:`string`
.. py:attribute:: header_model
4-character string (padded with whitespace) identifying the device
model, which shall match the signature contained in the
appropriate section of the ICC signature registry found at
www.color.org (see 7.2.13 of ICC.1:2010).
:type: :py:class:`string`
.. py:attribute:: attributes
Flags used to identify attributes unique to the particular device
setup for which the profile is applicable (see 7.2.14 of
ICC.1:2010 for details).
:type: :py:class:`int`
.. py:attribute:: rendering_intent
The rendering intent to use when combining this profile with
another profile (usually overridden at run-time, but provided here
for DeviceLink and embedded source profiles, see 7.2.15 of ICC.1:2010).
One of ``ImageCms.INTENT_ABSOLUTE_COLORIMETRIC``, ``ImageCms.INTENT_PERCEPTUAL``,
``ImageCms.INTENT_RELATIVE_COLORIMETRIC`` and ``ImageCms.INTENT_SATURATION``.
:type: :py:class:`int`
.. py:attribute:: profile_id
A sequence of 16 bytes identifying the profile (via a specially
constructed MD5 sum), or 16 binary zeroes if the profile ID has
not been calculated (see 7.2.18 of ICC.1:2010).
:type: :py:class:`bytes`
.. py:attribute:: copyright
The text copyright information for the profile (see 9.2.21 of ICC.1:2010).
:type: :py:class:`unicode` or ``None``
.. py:attribute:: manufacturer
The (English) display string for the device manufacturer (see
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9.2.22 of ICC.1:2010).
:type: :py:class:`unicode` or ``None``
.. py:attribute:: model
The (English) display string for the device model of the device
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for which this profile is created (see 9.2.23 of ICC.1:2010).
:type: :py:class:`unicode` or ``None``
.. py:attribute:: profile_description
The (English) display string for the profile description (see
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9.2.41 of ICC.1:2010).
:type: :py:class:`unicode` or ``None``
.. py:attribute:: target
The name of the registered characterization data set, or the
measurement data for a characterization target (see 9.2.14 of
ICC.1:2010).
:type: :py:class:`unicode` or ``None``
.. py:attribute:: red_colorant
The first column in the matrix used in matrix/TRC transforms (see 9.2.44 of ICC.1:2010).
:type: ``((X, Y, Z), (x, y, Y))`` or ``None``
.. py:attribute:: green_colorant
The second column in the matrix used in matrix/TRC transforms (see 9.2.30 of ICC.1:2010).
:type: ``((X, Y, Z), (x, y, Y))`` or ``None``
.. py:attribute:: blue_colorant
The third column in the matrix used in matrix/TRC transforms (see 9.2.4 of ICC.1:2010).
:type: ``((X, Y, Z), (x, y, Y))`` or ``None``
.. py:attribute:: luminance
The absolute luminance of emissive devices in candelas per square
metre as described by the Y channel (see 9.2.32 of ICC.1:2010).
:type: ``((X, Y, Z), (x, y, Y))`` or ``None``
.. py:attribute:: chromaticity
The data of the phosphor/colorant chromaticity set used (red,
green and blue channels, see 9.2.16 of ICC.1:2010).
:type: ``((x, y, Y), (x, y, Y), (x, y, Y))`` or ``None``
.. py:attribute:: chromatic_adaption
The chromatic adaption matrix converts a color measured using the
actual illumination conditions and relative to the actual adopted
white, to an color relative to the PCS adopted white, with
complete adaptation from the actual adopted white chromaticity to
the PCS adopted white chromaticity (see 9.2.15 of ICC.1:2010).
Two matrices are returned, one in (X, Y, Z) space and one in (x, y, Y) space.
:type: 2-tuple of 3-tuple, the first with (X, Y, Z) and the second with (x, y, Y) values
.. py:attribute:: colorant_table
This tag identifies the colorants used in the profile by a unique
name and set of PCSXYZ or PCSLAB values (see 9.2.19 of
ICC.1:2010).
:type: list of strings
.. py:attribute:: colorant_table_out
This tag identifies the colorants used in the profile by a unique
name and set of PCSLAB values (for DeviceLink profiles only, see
9.2.19 of ICC.1:2010).
:type: list of strings
.. py:attribute:: colorimetric_intent
4-character string (padded with whitespace) identifying the image
state of PCS colorimetry produced using the colorimetric intent
transforms (see 9.2.20 of ICC.1:2010 for details).
:type: :py:class:`string` or ``None``
.. py:attribute:: perceptual_rendering_intent_gamut
4-character string (padded with whitespace) identifying the (one)
standard reference medium gamut (see 9.2.37 of ICC.1:2010 for
details).
:type: :py:class:`string` or ``None``
.. py:attribute:: saturation_rendering_intent_gamut
4-character string (padded with whitespace) identifying the (one)
standard reference medium gamut (see 9.2.37 of ICC.1:2010 for
details).
:type: :py:class:`string` or ``None``
.. py:attribute:: technology
4-character string (padded with whitespace) identifying the device
technology (see 9.2.47 of ICC.1:2010 for details).
:type: :py:class:`string` or ``None``
.. py:attribute:: media_black_point
This tag specifies the media black point and is used for
generating absolute colorimetry.
This tag was available in ICC 3.2, but it is removed from
version 4.
:type: ``((X, Y, Z), (x, y, Y))`` or ``None``
.. py:attribute:: media_white_point_temperature
Calculates the white point temperature (see the LCMS documentation
for more information).
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:type: :py:class:`float` or ``None``
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.. py:attribute:: viewing_condition
The (English) display string for the viewing conditions (see
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9.2.48 of ICC.1:2010).
:type: :py:class:`unicode` or ``None``
.. py:attribute:: screening_description
The (English) display string for the screening conditions.
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This tag was available in ICC 3.2, but it is removed from
version 4.
:type: :py:class:`unicode` or ``None``
.. py:attribute:: red_primary
The XYZ-transformed of the RGB primary color red (1, 0, 0).
:type: ``((X, Y, Z), (x, y, Y))`` or ``None``
.. py:attribute:: green_primary
The XYZ-transformed of the RGB primary color green (0, 1, 0).
:type: ``((X, Y, Z), (x, y, Y))`` or ``None``
.. py:attribute:: blue_primary
The XYZ-transformed of the RGB primary color blue (0, 0, 1).
:type: ``((X, Y, Z), (x, y, Y))`` or ``None``
.. py:attribute:: is_matrix_shaper
True if this profile is implemented as a matrix shaper (see
documentation on LCMS).
:type: :py:class:`bool`
.. py:attribute:: clut
Returns a dictionary of all supported intents and directions for
the CLUT model.
The dictionary is indexed by intents
(``ImageCms.INTENT_ABSOLUTE_COLORIMETRIC``,
``ImageCms.INTENT_PERCEPTUAL``,
``ImageCms.INTENT_RELATIVE_COLORIMETRIC`` and
``ImageCms.INTENT_SATURATION``).
The values are 3-tuples indexed by directions
(``ImageCms.DIRECTION_INPUT``, ``ImageCms.DIRECTION_OUTPUT``,
``ImageCms.DIRECTION_PROOF``).
The elements of the tuple are booleans. If the value is ``True``,
that intent is supported for that direction.
:type: :py:class:`dict` of boolean 3-tuples
.. py:attribute:: intent_supported
Returns a dictionary of all supported intents and directions.
The dictionary is indexed by intents
(``ImageCms.INTENT_ABSOLUTE_COLORIMETRIC``,
``ImageCms.INTENT_PERCEPTUAL``,
``ImageCms.INTENT_RELATIVE_COLORIMETRIC`` and
``ImageCms.INTENT_SATURATION``).
The values are 3-tuples indexed by directions
(``ImageCms.DIRECTION_INPUT``, ``ImageCms.DIRECTION_OUTPUT``,
``ImageCms.DIRECTION_PROOF``).
The elements of the tuple are booleans. If the value is ``True``,
that intent is supported for that direction.
:type: :py:class:`dict` of boolean 3-tuples
.. py:attribute:: color_space
Deprecated but retained for backwards compatibility.
Interpreted value of :py:attr:`.xcolor_space`. May be the
empty string if value could not be decoded.
:type: :py:class:`string`
.. py:attribute:: pcs
Deprecated but retained for backwards compatibility.
Interpreted value of :py:attr:`.connection_space`. May be
the empty string if value could not be decoded.
:type: :py:class:`string`
.. py:attribute:: product_model
Deprecated but retained for backwards compatibility.
ASCII-encoded value of :py:attr:`.model`.
:type: :py:class:`string`
.. py:attribute:: product_manufacturer
Deprecated but retained for backwards compatibility.
ASCII-encoded value of :py:attr:`.manufacturer`.
:type: :py:class:`string`
.. py:attribute:: product_copyright
Deprecated but retained for backwards compatibility.
ASCII-encoded value of :py:attr:`.copyright`.
:type: :py:class:`string`
.. py:attribute:: product_description
Deprecated but retained for backwards compatibility.
ASCII-encoded value of :py:attr:`.profile_description`.
:type: :py:class:`string`
.. py:attribute:: product_desc
Deprecated but retained for backwards compatibility.
ASCII-encoded value of :py:attr:`.profile_description`.
This alias of :py:attr:`.product_description` used to
contain a derived informative string about the profile,
depending on the value of the description, copyright,
manufacturer and model fields).
:type: :py:class:`string`
There is one function defined on the class:
.. py:method:: is_intent_supported(intent, direction)
Returns if the intent is supported for the given direction.
Note that you can also get this information for all intents and directions
with :py:attr:`.intent_supported`.
:param intent: One of ``ImageCms.INTENT_ABSOLUTE_COLORIMETRIC``,
``ImageCms.INTENT_PERCEPTUAL``,
``ImageCms.INTENT_RELATIVE_COLORIMETRIC``
and ``ImageCms.INTENT_SATURATION``.
:param direction: One of ``ImageCms.DIRECTION_INPUT``,
``ImageCms.DIRECTION_OUTPUT``
and ``ImageCms.DIRECTION_PROOF``
:return: Boolean if the intent and direction is supported.