Color Profile Basic Concepts

It is often necessary to use color profiles in order to obtain desirable results when converting image data between color spaces such as CMYK and RGB. Different color spaces have different gamuts, or sets of colors that can be represented. Color profiles contain complex mappings that make it possible to carefully manage the translations of colors between different color spaces and gamuts.

A color profile defines instructions for how to map colors from a particular color space to and from a special intermediate color space known as the PCS a profile connection space. There are different ways to do this mapping, representing different tradeoffs and processes, so it is possible to use a wide variety of color profiles. Color profiles typically exist for different input and output devices, such as scanners, cameras, monitors, and printers. Their mappings take into account the physical device characteristics.

When performing color space conversion using color profiles, it is necessary to define a source color profile whose color space matches the color space of the image being converted, as well as a destination color profile whose color space matches the color space to which the image is to be converted.

In addition to source and destination color profiles, a rendering intent is also specified. The rendering intent allows additional control over the conversion process by indicating how certain tradeoffs should be made. For more information, see the ImGearRenderingIntents Enumeration and the ICC color profile specifications at www.color.org.