There are a lot of ways to specify colors. In general, we want to specify colors from a color space using a color model.
Color model decides how the color is represented, while color space specifies how those values correspond to actual perceptual colors.
For example, the RGB color model can used to represent colors in different color spaces such as sRGB.
Color spaces can be visualized by chromaticity diagram. It is usually draw from the tristimulus theory of color.
Color Models
There are a lot of color models besides RGB, such as
- HSV
- hue, saturation, value
- more intuitive than RGB/CMYK
- SML
- physiological model
- corresponds to stimulus of cones
- not practical for most color work
- XYZ (used for the CIE 1931 color space)
- perceptually-driven model
- Y captures luminance (intensity)
- X, Z capture chromaticity (color)
- related to, but different from, SML
- Lab - “perceptually uniform” modification of XYZ