ImageCms Module

The ImageCms module provides color profile management support using the LittleCMS2 color management engine, based on Kevin Cazabon’s PyCMS library.

CmsProfile

The ICC color profiles are wrapped in an instance of the 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).

class PIL.ImageCms.CmsProfile
creation_date

Date and time this profile was first created (see 7.2.1 of ICC.1:2010).

Type:datetime.datetime or None
version

The version number of the ICC standard that this profile follows (e.g. 2.0).

Type:float
icc_version

Same as version, but in encoded format (see 7.2.4 of ICC.1:2010).

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:string
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:string
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:string
header_flags

The encoded header flags of the profile (see 7.2.11 of ICC.1:2010 for details).

Type:int
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:string
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:string
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:int
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:int
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:bytes
copyright

The text copyright information for the profile (see 9.2.21 of ICC.1:2010).

Type:unicode or None
manufacturer

The (english) display string for the device manufacturer (see 9.2.22 of ICC.1:2010).

Type:unicode or None
model

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).

Type:unicode or None
profile_description

The (english) display string for the profile description (see 9.2.41 of ICC.1:2010).

Type:unicode or None
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:unicode or None
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
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
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
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
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
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
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
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
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:string or None
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:string or None
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:string or None
technology

4-character string (padded with whitespace) identifying the device technology (see 9.2.47 of ICC.1:2010 for details).

Type:string or None
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
media_white_point_temperature

Calculates the white point temperature (see the LCMS documentation for more information).

Type:float or None
viewing_condition

The (english) display string for the viewing conditions (see 9.2.48 of ICC.1:2010).

Type:unicode or None
screening_description

The (english) display string for the screening conditions.

This tag was available in ICC 3.2, but it is removed from version 4.

Type:unicode or None
red_primary

The XYZ-transformed of the RGB primary color red (1, 0, 0).

Type:((X, Y, Z), (x, y, Y)) or None
green_primary

The XYZ-transformed of the RGB primary color green (0, 1, 0).

Type:((X, Y, Z), (x, y, Y)) or None
blue_primary

The XYZ-transformed of the RGB primary color blue (0, 0, 1).

Type:((X, Y, Z), (x, y, Y)) or None
is_matrix_shaper

True if this profile is implemented as a matrix shaper (see documentation on LCMS).

Type:bool
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:dict of boolean 3-tuples
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:dict of boolean 3-tuples
color_space

Deprecated but retained for backwards compatibility. Interpreted value of xcolor_space. May be the empty string if value could not be decoded.

Type:string
pcs

Deprecated but retained for backwards compatibility. Interpreted value of connection_space. May be the empty string if value could not be decoded.

Type:string
product_model

Deprecated but retained for backwards compatibility. ASCII-encoded value of model.

Type:string
product_manufacturer

Deprecated but retained for backwards compatibility. ASCII-encoded value of manufacturer.

Type:string

Deprecated but retained for backwards compatibility. ASCII-encoded value of copyright.

Type:string
product_description

Deprecated but retained for backwards compatibility. ASCII-encoded value of profile_description.

Type:string
product_desc

Deprecated but retained for backwards compatibility. ASCII-encoded value of profile_description.

This alias of 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:string

There is one function defined on the class:

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 intent_supported.

Parameters:
  • intent – One of ImageCms.INTENT_ABSOLUTE_COLORIMETRIC, ImageCms.INTENT_PERCEPTUAL, ImageCms.INTENT_RELATIVE_COLORIMETRIC and ImageCms.INTENT_SATURATION.
  • direction – One of ImageCms.DIRECTION_INPUT, ImageCms.DIRECTION_OUTPUT and ImageCms.DIRECTION_PROOF
Returns:

Boolean if the intent and direction is supported.