How to convert sRGB to CIELAb and CIELab to sRGB efficiently?

Question

I don't understand how to convert sRGB to CIELab and backward. Help me please. it's desirable in с++ code

Answer 1

Convert from sRGB to RGB by applying inverse gamma, convert RGB to XYZ using 3x3 matrix, convert XYZ to Lab using standard formula and D6500 white point

References:

• Lab http://en.wikipedia.org/wiki/Lab_color_space
• sRBG http://en.wikipedia.org/wiki/SRGB_color_space

The rest... you can do on your own :-)