Profile Data
The profile data is the actual color profile information, in the form of a ColorSync color profile structure. A QuickDraw GX color profile object is a wrapper for a ColorSync profile.ColorSync profiles are specified by the
CMProfilestructure, which consists of the following parts:
The details of the
- Header. A structure containing information such as the size, version, device type, and attributes of the profile. The header also contains the XYZ chromaticities of the device's white point and black point, and an options field that specifies the type of color matching preferred (such as perceptual, colorimetric, or saturation matching).
- Profile chromaticities. A structure that contains the XYZ chromaticities for the six primary and secondary colors (red, green, blue, cyan, magenta, yellow) at the limits of the device's gamut.
- Profile response curves. A variable-sized array of response curves for each of the primary and secondary colors, plus gray (plus black generation and undercolor removal for printer profiles).
- Name string. An international string, which consists of a Macintosh script code followed by a 63-byte text string, that identifies the profile. (Note that these are Macintosh script codes, which differ from QuickDraw GX script codes; Macintosh script codes are described in the Script Manager chapter of Inside Macintosh: Text.)
- Custom data. Information used by custom color-matching methods. It may include other kinds of color values or response curves.
CMProfilestructure, including explanations of some of the terms used here, are given in the ColorSync Utilities chapter of Inside Macintosh: Advanced Color Imaging. All parts of the structure except for the custom data are accessible through ColorSync function calls. QuickDraw GX defines no structures or types for the profile data of a color profile object, although you can access the information if you know its format. See "Manipulating the Profile Data in a Color Profile Object" beginning on page 4-48.