convert mesh color to scale factor

I have a mesh which I ran a radiation analysis on in Ladybug and I would like the mesh colors of that analysis to control the size of openings on the mesh faces.

What would be the best way of achieving this? All the examples i saw online used a gradient to recolor the mesh, but since i already have the color information i would only like to transform them to data, specifically a value between 0.0 to 1.0

Thanks!