Question: Build a color constancy algorithm that uses the assumption that the spatial average of reflectance is constant. Use finite-dimensional linear models. You can get values of gijk from your solution to exercise.
Exercise: Fitting a finite-dimensional linear model to illuminants and reflectances separately is somewhat ill-advised, because there is no guarantee that the interactions will be represented well (they're not accounted for in the fitting error). It turns out that one can obtain gijk by a fitting process that sidesteps the use of basis functions. Implement this procedure (which is described in detail [in?]), and compare the results with those obtained from the previous assignment.