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TSL is a color space that is based on Tint, Saturation, and Luminance.

The transformation from RGB to TSL is:

S = \sqrt{\frac{9}{5}\left( r'^2 + g'^2 \right)}

T = \begin{cases} \frac{1}{2\pi} \arctan{\frac{r'}{g'}} + \frac{1}{4}, & \mbox{if}~g' \neq 0 \and \frac{r'}{g'} > 0 \\ \frac{1}{2\pi} \arctan{\frac{r'}{g'}} + \frac{3}{4}, & \mbox{if}~g' \neq 0 \and \frac{r'}{g'} < 0 \\ \frac{1}{2}, & \mbox{if}~g'=0 \\ \end{cases}

L = 0.299R + 0.587G + 0.114B

where:

r' = r - \tfrac{1}{3}

g' = g - \tfrac{1}{3}

r = \tfrac{R}{R+G+B}

g = \tfrac{G}{R+G+B}

An earlier version of the formula for T used the sign of g' to determine whether to add \tfrac{1}{4} or \tfrac{3}{4} to \tfrac{1}{2\pi} arctan {\tfrac{r'}{g'}}. That formula generates a discontinuity in the calculated T values for g' near zero; using the sign of \tfrac{r'}{g'} gives a continuous value of \tfrac{1}{2} for for g' near zero.

[1]

[edit] References

  1. ^ Terrillon, Jean-Christophe; Shigeru Akamatsu (2000). "Comparative Performance of Different Chrominance Spaces for Color Segmentation". International Conf on Face and Gesture Recognition: 54-61. 

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Category:Color space