1. An image adjustment system comprising: an adaptive palette processor configured to adapt a universal palette to generate (i) an input image palette statistically representative of pixels of an input image and (ii) a reference image palette statistically representative of pixels of a reference image; and an image adjustment processor configured to adjust at least some pixels of the input image to generate adjusted pixels that are statistically represented by the reference image palette; wherein the input image palette comprises an input image mixture model, the reference image palette comprises a reference image mixture model, and there is a one-to-one correspondence between components of the input image mixture model and components of the reference image mixture model.