CMYK color model color reproduction and they may be viewed as the inverse of RGB. Cyan absorbs Red, Magenta absorbs Green, and Yellow absorbs Blue (-R,-G,-B). Since RGB and CMYK spaces are both device-dependent spaces, there is no simple or general conversion formula that converts between them. Conversions are generally done through color management systems, using color profiles that describe the spaces being converted. Nevertheless, the conversions cannot be exact, particularly where these spaces have different gamuts. The problem of computing a colorimetric estimate of the color that results from printing various combinations of ink has been addressed by many scientists. A general
Subtractive color the spectrum. Magenta is the complement of green, and yellow the complement of blue. Combinations of different amounts of the three can produce a wide range of colors with good saturation. In inkjet color printing and typical mass production photomechanical printing processes, a black ink K (Key) component is included, resulting in the CMYK color model. The black ink serves to cover unwanted tints in dark areas of the printed image, which result from the imperfect transparency of commercially practical CMY inks; to improve image sharpness, which tends to be degraded by imperfect registration of the three color elements; and