DICOM PS3.3 2019d - Information Object Definitions

C.11.15 ICC Profile Module

Table C.11.15-1 contains Attributes that identify and describe an ICC Profile.

Table C.11.15-1. ICC Profile Module Attributes

Attribute Name

Tag

Type

Attribute Description

ICC Profile

(0028,2000)

1

An ICC Profile encoding the transformation of device-dependent color stored pixel values into PCS-Values.

Color Space

(0028,2002)

3

A label that identifies the well-known color space of the image. Shall be consistent with any ICC Profile (0028,2000) that is also present.

See Section C.11.15.1.2.


C.11.15.1 Attribute Descriptions

C.11.15.1.1 ICC Profile

ICC Profile (0028,2000) encodes an ICC Input Device Profile that encodes the transformation of device-dependent color stored pixel values into PCS-Values.

Note

  1. Only Input Device profiles are encoded, since display and output device profiles are not interchanged in DICOM, though they may be used internally within display and output devices, for example when they are calibrated.

  2. Since the version of the ICC Profile is encoded within the profile itself, no additional version information is encoded in the ICC Profile Module.

The following constraints on the encoding of the ICC Profile shall be observed:

  • The profile shall be of the Input Device class, i.e., header bytes 12 through15, Profile Device/Class Signature, shall be "scnr"

  • The color space of the input shall be RGB, i.e., header bytes 16 through 19, Color Space Signature, shall be "RGB", regardless of the Photometric Interpretation of the image pixel data prior to decompression

  • PCS shall be CIELab or CIEXYZ, i.e., header bytes 20 through 23, Profile Connection Space, shall be either "Lab" or "XYZ".

    Note

    1. In the case of a PCS of CIELab, the profile will contain an N-component LUT-based AtoB0Tag, since three-component matrix based transformations are only possible with a PCS of CIEXYZ. A three-component matrix based transformation might be used to define a well-known rather than device-specific profile for such spaces as sRGB.

    2. Selection of a PCS of CIELab or CIEXYZ within the ICC profile does not impact the DICOM encoding, since all color management systems support both.

The following constraints on the encoding of the ICC Profile are recommended:

  • The Rendering Intent should be Perceptual.

    Note

    1. The rendering intent specifies how rendering will take place when the ICC Input Profile is linked with another Profile for the purpose of display.

    2. A perceptual rendering intent implies that AtoB0Tag and BtoA0Tag tags will be present in the profile. The AtoB0Tag allows mapping from the input values to the PCS. The BtoA0Tag allows mapping from the PCS to the input values, though this is not required for the color rendering pipeline defined in PS3.4.

  • All LUTs should be represented as 16 bit values, using tag type lut16Type, for greater precision.

  • The chromaticAdaptationTag should be set if the actual illumination source is not D50.

    Note

    See the discussion of white point in PS3.4.

C.11.15.1.2 Color Space

The Color Space Attribute provides a label that identifies the color space by name, when the ICC Profile (0028, 2000) (if present) describes a well-known color space.

Defined Terms:

SRGB

ICC Profile (0028,2000) defines sRGB color space [IEC 61966-2.1]

ADOBERGB

ICC Profile (0028,2000) defines Adobe RGB color space [Adobe RGB]

ROMMRGB

ICC Profile (0028,2000) defines ROMM RGB color space [ISO 22028-2]

DICOM PS3.3 2019d - Information Object Definitions