The Rgb color space consists of all possible colors that can be made by the combination of red, green, and blue light. It's a popular model in photography, television, and computer graphics.
Cie-L*ab is defined by lightness and the color-opponent dimensions a and b, which are based on the compressed Xyz color space coordinates. Lab is particularly notable for it's use in delta-e calculations. Read more about it here.
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Color conversions performed using the open source ColorMine library.