A color appearance model cam is a mathematical model that seeks to describe the perceptual aspects of human color vision ie viewing conditions under which the appearance of a color does not tally with the corresponding physical measurement of the stimulus source. The 3 rd edition of color appearance models contains numerous new and expanded sections providing an updated review of color appearance and includes many of the most widely used models to date ensuring its continued success as the comprehensive resource on color appearance models key features. Color appearance models are useful to predict colors that are presented on a precisely defined background with known illumination it is tempting to apply such models to images and video especially to adjust such content for display in various viewing environments each pixel would then be treated as an independent patch of color however our doing so would result in the implicit assumption that the proximal field background and surround of each pixel would be the same and could be . Color appearance model o any model that includes predictors of at least the relative color appearance attributes of lightness chroma and hue o it must include at least some form of a chromatic adaptation transform 23