Spherical Sampling and Color Transformations

In this paper, we present a spherical sampling technique that can be employed to find optimal sensors for trichromatic color applications. The advantage over other optimization techniques is that it assures a global minimum is found, and that not only one, but a set of solutions is retained if so desired. The sampling technique is used to find all possible RGB sensors that exhibit favorable chromatic adaptation transform (CAT) behavior when tested on Lam’s corresponding color data set, subject to a CIE Delta E₉₄ error criterion. We found that there are a number of sensors that meet the criterion, and that the Bradford, Sharp, and CMCCAT2000 sensors are not unique.