Extracting color information from lit regions to adjust shadow regions, HSV space
Probably not – the observed color of a material is a result of the composition of light that illuminates the spot, and what of that the material reflects.
For example, if you have a bright light with strong red/yellow component (&quot;warm light&quot;), and you have ambient/scattered light at a lower level that's more or less white, then a green spot in the bright area will have a different tint than in the shadow.
(note: a shadow isn't perfect darkness, otherwise everything there would be the blackest of blacks.)
So, you need have a model of at least your main light and how ambient light, eg. from scattering that on a not-quite-perfectly-white wall, changes the spectrum of that, and of the actual color of the material (which you can't see in either, unless one of these is a reference white light source...).