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Managing Color With ColorSync


When Color Matching Occurs

When the color gamut of a source profile is different from the color gamut of a destination profile, ColorSync relies on the CMM and the information stored in both profiles for mapping the colors from the source profile's gamut to the destination profile's gamut. The CMM contains the necessary algorithms and lookup tables to enable consistent color mapping among devices.

When an application or device driver uses the ColorSync Manager functions for color matching, it specifies the source and destination profiles. If it does not specify the source profile or the destination profile for a matching operation, ColorSync substitutes a default profile. See Setting Default Profiles for more information.

Figure 2-2 The ColorSync Manager and the Component Manager

Color matching between the source and destination color spaces happens inside the color management module (CMM) component. Figure 2-2 shows the relationship between your application or device driver, the ColorSync Manager, the Component Manager, and one or more available CMM components.

Your application can call any ColorSync Manager function, whether QuickDraw-specific or general purpose. One of three things then happens:

General purpose and QuickDraw-specific functions are described in the following sections.

General Purpose Color-Matching Functions

A general purpose color-matching function is one that uses a color world to characterize how to perform color-matching. General purpose functions depend on the information contained in the profiles that you supply when you set up the color world. You can define a color world for color transformations between a source profile and a destination profile, or define a color world for color transformations between a series of concatenated profiles.

Creating a Color World to Use With the General Purpose Functions provides a code sample for working with general purpose functions. Matching Colors Using General Purpose Functions lists the general purpose functions and provides a description of each function.

In contrast to the general purpose color-matching functions, the QuickDraw-Specific Color-Matching Functions are tailored for color-matching with QuickDraw. Note, however, that you can also use the general purpose functions when working with QuickDraw--for example, if you need the greater level of control the general purpose functions provide.

QuickDraw-Specific Color-Matching Functions

A QuickDraw-specific color-matching function is one that uses QuickDraw to provide images showing consistent colors across displays. The ColorSync Manager provides two QuickDraw-specific functions that your application can call to draw a color picture to the current display:

Matching to Displays Using QuickDraw-Specific Operations provides a code sample for working with QuickDraw-specific functions. Matching Colors Using QuickDraw-Specific Functions lists the QuickDraw-specific functions and provides a description of each function. Note that the QuickDraw-specific functions call upon the general purpose functions to perform their operations, as shown in Figure 2-2 .


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