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.