Hue to wavelength mapping

Question

Is there an algorithm to find out the wavelength of the color given the hue value (between 0 degree to 360 degree). Is there any built-in function in MATLABfor the same?

Answer 1

While Mark Ransom and Franco Callari are completely right that you cannot recover the spectrum of a perceptual color, nor unambiguously map hue values to wavelengths, you could definitely piece something together if you just want the corresponding monochromatic wavelength.

The part of the hue cycle between 270 and 360 is another problem. There is nothing corresponding to pink or magenta in the light spectrum, so let's assume that we only use hue values between 0 and 270 degrees.

Estimating that the usable part of the visible spectrum is 400-650nm, with wavelength L (in nm) and hue value H (in degrees), you can improvise this:

 L = 650 - 250 / 270 * H

650 is the maximum wavelength, 250 is the wavelength range and 270 is the hue range.

I think this should be in the right direction but there may of course be room for improvement. You might be able to get better results comparing between input hues and corresponding colors on a visible spectrum chart, and then adjusting the values somewhat.