Pillow/docs/reference/ImageCms.rst
Ondrej Baranovič 81ea98e494
document ImageCmsTransform's base class
Co-authored-by: Andrew Murray <3112309+radarhere@users.noreply.github.com>
2024-01-02 14:10:07 +01:00

387 lines
13 KiB
ReStructuredText

.. py:module:: PIL.ImageCms
.. py:currentmodule:: PIL.ImageCms
:py:mod:`~PIL.ImageCms` Module
==============================
The :py:mod:`~PIL.ImageCms` module provides color profile management
support using the LittleCMS2 color management engine, based on Kevin
Cazabon's PyCMS library.
.. autoclass:: ImageCmsProfile
:members:
:special-members: __init__
.. autoclass:: ImageCmsTransform
:members:
:undoc-members:
:show-inheritance:
.. autoexception:: PyCMSError
Constants
---------
.. autoclass:: Intent
:members:
:member-order: bysource
:undoc-members:
.. autoclass:: Direction
:members:
:member-order: bysource
:undoc-members:
.. autoclass:: Flags
:members:
:member-order: bysource
:undoc-members:
Functions
---------
.. autofunction:: applyTransform
.. autofunction:: buildProofTransform
.. autofunction:: buildProofTransformFromOpenProfiles
.. autofunction:: buildTransform
.. autofunction:: buildTransformFromOpenProfiles
.. autofunction:: createProfile
.. autofunction:: getDefaultIntent
.. autofunction:: getOpenProfile
.. autofunction:: getProfileCopyright
.. autofunction:: getProfileDescription
.. autofunction:: getProfileInfo
.. autofunction:: getProfileManufacturer
.. autofunction:: getProfileModel
.. autofunction:: getProfileName
.. autofunction:: get_display_profile
.. autofunction:: isIntentSupported
.. autofunction:: profileToProfile
.. autofunction:: versions
CmsProfile
----------
The ICC color profiles are wrapped in an instance of the class
:py:class:`~core.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:currentmodule:: PIL.ImageCms.core
.. py:class:: CmsProfile
:canonical: PIL._imagingcms.CmsProfile
.. py:attribute:: creation_date
:type: Optional[datetime.datetime]
Date and time this profile was first created (see 7.2.1 of ICC.1:2010).
.. py:attribute:: version
:type: float
The version number of the ICC standard that this profile follows
(e.g. ``2.0``).
.. py:attribute:: icc_version
:type: int
Same as ``version``, but in encoded format (see 7.2.4 of ICC.1:2010).
.. py:attribute:: device_class
:type: str
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).
.. py:attribute:: xcolor_space
:type: str
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).
.. py:attribute:: connection_space
:type: str
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).
.. py:attribute:: header_flags
:type: int
The encoded header flags of the profile (see 7.2.11 of ICC.1:2010
for details).
.. py:attribute:: header_manufacturer
:type: str
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).
.. py:attribute:: header_model
:type: str
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).
.. py:attribute:: attributes
:type: int
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).
.. py:attribute:: rendering_intent
:type: int
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``.
.. py:attribute:: profile_id
:type: bytes
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).
.. py:attribute:: copyright
:type: Optional[str]
The text copyright information for the profile (see 9.2.21 of ICC.1:2010).
.. py:attribute:: manufacturer
:type: Optional[str]
The (English) display string for the device manufacturer (see
9.2.22 of ICC.1:2010).
.. py:attribute:: model
:type: Optional[str]
The (English) display string for the device model of the device
for which this profile is created (see 9.2.23 of ICC.1:2010).
.. py:attribute:: profile_description
:type: Optional[str]
The (English) display string for the profile description (see
9.2.41 of ICC.1:2010).
.. py:attribute:: target
:type: Optional[str]
The name of the registered characterization data set, or the
measurement data for a characterization target (see 9.2.14 of
ICC.1:2010).
.. py:attribute:: red_colorant
:type: Optional[tuple[tuple[float]]]
The first column in the matrix used in matrix/TRC transforms (see 9.2.44 of ICC.1:2010).
The value is in the format ``((X, Y, Z), (x, y, Y))``, if available.
.. py:attribute:: green_colorant
:type: Optional[tuple[tuple[float]]]
The second column in the matrix used in matrix/TRC transforms (see 9.2.30 of ICC.1:2010).
The value is in the format ``((X, Y, Z), (x, y, Y))``, if available.
.. py:attribute:: blue_colorant
:type: Optional[tuple[tuple[float]]]
The third column in the matrix used in matrix/TRC transforms (see 9.2.4 of ICC.1:2010).
The value is in the format ``((X, Y, Z), (x, y, Y))``, if available.
.. py:attribute:: luminance
:type: Optional[tuple[tuple[float]]]
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).
The value is in the format ``((X, Y, Z), (x, y, Y))``, if available.
.. py:attribute:: chromaticity
:type: Optional[tuple[tuple[float]]]
The data of the phosphor/colorant chromaticity set used (red,
green and blue channels, see 9.2.16 of ICC.1:2010).
The value is in the format ``((x, y, Y), (x, y, Y), (x, y, Y))``, if available.
.. py:attribute:: chromatic_adaption
:type: tuple[tuple[float]]
The chromatic adaption matrix converts a color measured using the
actual illumination conditions and relative to the actual adopted
white, to a 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 3-tuples of floats are returned in a 2-tuple,
one in (X, Y, Z) space and one in (x, y, Y) space.
.. py:attribute:: colorant_table
:type: list[str]
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).
.. py:attribute:: colorant_table_out
:type: list[str]
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).
.. py:attribute:: colorimetric_intent
:type: Optional[str]
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).
.. py:attribute:: perceptual_rendering_intent_gamut
:type: Optional[str]
4-character string (padded with whitespace) identifying the (one)
standard reference medium gamut (see 9.2.37 of ICC.1:2010 for
details).
.. py:attribute:: saturation_rendering_intent_gamut
:type: Optional[str]
4-character string (padded with whitespace) identifying the (one)
standard reference medium gamut (see 9.2.37 of ICC.1:2010 for
details).
.. py:attribute:: technology
:type: Optional[str]
4-character string (padded with whitespace) identifying the device
technology (see 9.2.47 of ICC.1:2010 for details).
.. py:attribute:: media_black_point
:type: Optional[tuple[tuple[float]]]
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.
The value is in the format ``((X, Y, Z), (x, y, Y))``, if available.
.. py:attribute:: media_white_point_temperature
:type: Optional[float]
Calculates the white point temperature (see the LCMS documentation
for more information).
.. py:attribute:: viewing_condition
:type: Optional[str]
The (English) display string for the viewing conditions (see
9.2.48 of ICC.1:2010).
.. py:attribute:: screening_description
:type: Optional[str]
The (English) display string for the screening conditions.
This tag was available in ICC 3.2, but it is removed from
version 4.
.. py:attribute:: red_primary
:type: Optional[tuple[tuple[float]]]
The XYZ-transformed of the RGB primary color red (1, 0, 0).
The value is in the format ``((X, Y, Z), (x, y, Y))``, if available.
.. py:attribute:: green_primary
:type: Optional[tuple[tuple[float]]]
The XYZ-transformed of the RGB primary color green (0, 1, 0).
The value is in the format ``((X, Y, Z), (x, y, Y))``, if available.
.. py:attribute:: blue_primary
:type: Optional[tuple[tuple[float]]]
The XYZ-transformed of the RGB primary color blue (0, 0, 1).
The value is in the format ``((X, Y, Z), (x, y, Y))``, if available.
.. py:attribute:: is_matrix_shaper
:type: bool
True if this profile is implemented as a matrix shaper (see
documentation on LCMS).
.. py:attribute:: clut
:type: dict[tuple[bool]]
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.
.. py:attribute:: intent_supported
:type: dict[tuple[bool]]
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.
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.