Absolute Color Space
A color space is a mathematical representation of our visual perceptions. In the absolute color space, colors are represented by points in CIEXYZ. Absolute color space profile is device independent, hence its profile is also known as non-device type profile. All visible colors have absolute or non-negative XYZ co-ordinates in CIEXYZ. The relative distance between these points is an indication of the difference between the colors and that simplifies and helps us in analyzing color reproduction capability mathematically. sRGB, Adobe RGB and ProPhoto RGB are among the most widely used absolute color spaces.
Color Conversion in Color Spaces
A color can be converted from one color space to another or vice verse. Such conversion in absolute color space is carried out by matrix transformation that has been built into the color space profile. Absolute Color Space profile is charactaerised by its compactness in file size and that it can be easily tagged into a image file with little overhead added to the resulting output.
Differences between Absolute and Generic Color Space
Absolute Color Space
1. Profile type e.g. monitor, TV screen.
2. Non-device type is characterized by its linearity behavior and can be described with mathematical function.
3. Color Conversion is matrix based, converted data is always smooth and continuous.
4. Cannot perform Perceptual color space conversion.
5. With RelCol (Relative Colorimetric), change in hue or color shift is better control and acceptable.
Generic Color Space
1. Profiles for I/O devices such as scanner, camera or printer.
2. Some output devices are non-linear and they cannot be fully described with simple mathematical function.
3 Color Conversion with Cluts (Color Look Up Table) is preferred, output with Cluts is discrete by nature and output resolution greatly depends upon the size of the Cluts and its implementation algorithm.
4. Mapping function for Perceptual conversion is built into the profile.
5. Change in hue or color shift is unavoidable due to CMM color matching, that also depends upon the workflow and how CMM is being implemented.
References
icc specification 4.2
CIELab Color Space by Gernot Hoffmann
A color space is a mathematical representation of our visual perceptions. In the absolute color space, colors are represented by points in CIEXYZ. Absolute color space profile is device independent, hence its profile is also known as non-device type profile. All visible colors have absolute or non-negative XYZ co-ordinates in CIEXYZ. The relative distance between these points is an indication of the difference between the colors and that simplifies and helps us in analyzing color reproduction capability mathematically. sRGB, Adobe RGB and ProPhoto RGB are among the most widely used absolute color spaces.
Color Conversion in Color Spaces
A color can be converted from one color space to another or vice verse. Such conversion in absolute color space is carried out by matrix transformation that has been built into the color space profile. Absolute Color Space profile is charactaerised by its compactness in file size and that it can be easily tagged into a image file with little overhead added to the resulting output.
Differences between Absolute and Generic Color Space
Absolute Color Space
1. Profile type e.g. monitor, TV screen.
2. Non-device type is characterized by its linearity behavior and can be described with mathematical function.
3. Color Conversion is matrix based, converted data is always smooth and continuous.
4. Cannot perform Perceptual color space conversion.
5. With RelCol (Relative Colorimetric), change in hue or color shift is better control and acceptable.
Generic Color Space
1. Profiles for I/O devices such as scanner, camera or printer.
2. Some output devices are non-linear and they cannot be fully described with simple mathematical function.
3 Color Conversion with Cluts (Color Look Up Table) is preferred, output with Cluts is discrete by nature and output resolution greatly depends upon the size of the Cluts and its implementation algorithm.
4. Mapping function for Perceptual conversion is built into the profile.
5. Change in hue or color shift is unavoidable due to CMM color matching, that also depends upon the workflow and how CMM is being implemented.
References
icc specification 4.2
CIELab Color Space by Gernot Hoffmann
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