Profile Types

The KCMS framework supports several types of color profiles. Before describing these types, there are some terminology differences between the ICC specification and the KCMS framework you should be aware of. Table 2-1 identifies these differences, which are mostly historical.

Table 2-1 KCMS and ICC Profile Format Equivalents

KCMS Profile Format	ICC Equivalent
device color profile (DCP)	any input, display, or output profile
color space profile (CSP)	color space conversion profile
effects color profile (ECP)	abstract profile
complete color profile (CCP)	device link profile

Device Color Profile

A device color profile (DCP) represents the behavior of a specific digital color device, such as a flatbed or film scanner, a computer monitor, or a printer. Each DCP specifies device color appearance under a specific set of conditions (for example, lighting type, media type, and so on). Because device behavior tends to change over time, calibration software may adjust a DCP whenever its device is calibrated. Calibration fine tunes a specific device's color response by bring it back to normal using lookup tables. Typically calibration changes the profile data so that it can be color managed to produce the same color response as other devices of the same make and model. In other cases, depending on the device's method of calibration, the device itself is changed to match the profile.

The ICC specification separates DCPs into three categories: input, output, and display. This separation can be confusing when a device, such as a printer includes input device data. The data can be considered an input profile, an output profile, or both. This occurs in print simulation where the printer is an input device to a display or other output device.

Conceptually, it may be easier to separate profiles into these three categories only in terms of how data can and cannot be sent from and to the profile connection space (PCS). The PCS is the common junction where profiles are connected together.

KCMS does not make this syntactical separation. Rather it considers all input, output, and display profiles as device profiles and makes no assumptions about what profiles can and cannot be connected together. The connection of the profiles is then evaluated at connection time based on the data contained within the profile.

Color Space Profile

A color space profile (CSP) defines a color space. Colors are defined in terms directly related to spectral response. A CSP does not depend on the behavior of a particular color device. CSPs contain information about assumed viewing conditions in the data expressed for that color space. Typically, the color space can be relative to CIEXYZ values, defined by the Commission Internationale de l'Eclairage (CIE). The equivalent ICC term for color space profile is color space conversion profile. (See Table 2-1.)

Effects Color Profile

An effects color profile (ECP) represents a condition that changes the appearance of colors, such as a specific kind of lighting or a simulated anomalous color vision (color blindness). In addition, an ECP can be applied for artistic purposes, such as making colors appear lighter or darker. The equivalent ICC term for effects color profile is abstract profile. (See Table 2-1.)

Complete Color Profile

The preceding three profile types do not contain enough information for the KCMS framework to convert color data from one form to another. Useful color transformations can only happen when your application uses the KCMS API to connect two or more profiles together to form a complete color profile (CCP). A CCP is a connected sequence of profiles with a DCP or a CSP at either end, and possibly one or more ECPs or DCPs in between. The equivalent ICC term for complete color profile is device link profile. (See Table 2-1.)