L*C*huv is the Cylindrical form of L*u*v*
space, where u*,v* have been transformed into a Chrominance value
and Hue angle in degrees.
Being derived directly from L*u*v* space, it has is a white
relative space, where the reference white has the L*C*h*uv
value 100,0,0. The typical assumption is that an observer is
adapted to the white reference, so that the L*C*h*uv
coordinates correspond to the colors relative to that white.