I don't think they use the Lab color space, except if you define your own colors to use in the palette, did you see a reference to it? From their encoding spec

I don't think they use the Lab color space, except if you define your own colors to use in the palette, did you see a reference to it? From their encoding spec: > In order to optimize the decoding of JAB Code, the used colors shall be so distinguishable as possible. Therefore, the used colors shall keep a distance from each other in the RGB color space cube > In case of 256-color-mode, the color channel R and G take eight values, 0, 36, 73, 109, 146, 182, 219 and 255, and the color channel B takes four values, 0, 85, 170 and 255, which will totally generate 256 colors. Which is too bad, because your idea of using Lab with ChromaTags to enable quick and accurate finding of the symbol was a really insightful technique. The decoding algorithm they suggest seems like it would be slow, and their use of RGB seems like a whole bunch of issues due to color-selective fading, shadows, damage, lighting, incorrect printer calibration, etc.