c l = { c s 12.92 , if c s ≤ 0.04045 ( c s + 0.055 1.055 ) 2.4 , if c s > 0.04045 {\displaystyle c_{l}={\begin{cases}{\tfrac {c_{s}}{12.92}},&{\text{if }}c_{s}\leq 0.04045\\\left({\tfrac {c_{s}+0.055}{1.055}}\right)^{2.4},&{\text{if }}c_{s}>0.04045\end{cases}}}