23.1: Invited Paper: Isoluminous Color Difference Metric for Application to Displays

This paper provides a methodology which bridges the gap between a simple color-difference metric and a full spatio-chromatic vision model to predict color differences. Because luminance and chromatic visual channels differ greatly in their spatial sensitivities, more than a single number is needed for specific applications—e.g., performance of softcopy displays. On the other hand, a full vision model implies dependence on the displayed images as well as on the display device, and may be impractical to implement. The compromise proposed here is to adopt in certain cases two color-difference metrics, one for luminance and the other for chrominance. Because chromatic coordinates are not luminance-independent in uniform color spaces such as CIELAB, the endpoints of the color difference are made isoluminous prior to transformation to a uniform-color space.