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About ICC-Colormanagement |
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 The International Color Consortium ICC was founded in 1992. A standard for color profiles was published in 1993 by the ICC. Today the ICC-standard for color profiles is established in most colormanagement systems.
The following illustration shows how ICC-colormanagement controls the color reproduction from input to output device.
ICC-profiles are used in colormanagement systems to get an accurate color reproduction on different output devices. ICC-profiles are OS independent and can be used on Windows based computers, on Macs and on Unix maschines. ColorSync is doing the colormanagement in the MacOS. On Windows based PCs ICM 2.0 is available in Windows 98/2000/XP. Today most popular DTP and image editing applications have an implemented support for colormanagement with ICC-profiles. 
An ICC-colormanagement system constits of color profiles and color engine (CMM). The color engine is doing the color transformation.
Inside of a color profile you find a matrix or table (LookUpTable, LUT) which are used for for calculation from device colorspace to teh device independent collorspace (PCS). The device colorspace is RGB for scanner and display and CMYK for printer. ICC-profiles have the extension *.icc or *.icm.
The color engine (CMM) is doing the calculation during a color transformation from device colorspace to the profile connection space (PCS) or vice versa by using the ICC-profiles. All calcualtions or automaticlly done by the color engine.
The device independent colorspace is called profile-connection-space (PCS). The ICC-standard allows two profile-connection-spaces: CIE-XYZ and CIELab. Both colorspaces can be converted lossless. For matrix-based-profiles a transformation to CIE-XYZ is used. ICC-profiles which include a look-up-table (LUT) for the color transformation convert to CIELab. |
