| This dissertation proposes a new color appearance model for color reproduction applications in graphic arts called the Uniform Color Appearance Model (UCAM). UCAM incorporates a simplified chromatic adaptation transformation with a generalized tonal reproduction and color correction; in addition, UCAM includes a capability that accounts for changes in media and viewing conditions. An expanded Munsell color space is applied to calculate the metrics of lightness, chroma, hue, and color difference, as well as manipulate color in a perceptually uniform manner.; The algorithms to establish the new model are discussed. These algorithms include the simplified chromatic adaptation transformation, the generalized tonal reproduction and color correction, the Munsell color space expansion, and the color conversion for the Munsell color space.; Three experiments are designed and conducted to evaluate UCAM and its algorithms. The first experiment tests the chromatic adaptation transformation and color correction algorithm across various viewing conditions. The second experiment tests the uniformity of the Munsell color space for hue reproduction. The third experiment visually compares UCAM against the CIELAB and CIELUV models by using transparency-to-print color reproductions of three natural images.; Experiment results are as follows: first, UCAM produces a better fit to the test data for chromatic adaptation and a significant better fit to the test data for adapting level change than other tested models. Second, UCAM reproduces hues like their originals in the perceptual (Munsell) hue. However, the hues could be quite different when comparing to CIELAB and CIELUV models, especially the blue of CIELAB and the red of CIELUV. Finally, UCAM reproduces images closer to their originals than those of CIELAB and CIELUV models particularly for images with saturated colors. |
