Application of fuzzy logic in color reproduction processes

Color quality appraisal refers to a visual evaluation of an original color image and an assessment of the degree to which that image is matched in photomechanical or electronic reproduction. The evaluation of reproduction quality is quite subjective, since it relies on the individual judgments of color technicians who have different perceptions of color and its component qualities.; If the quality of the reproduction as compared to the original is not acceptable to the color expert, then the reproduction enters a color correction cycle where the reproduced image is manipulated in highlight, midtone, or shadows to achieve a better "match" to the original.; The reproduction process has inherent limitations because the best reproduction cannot physically produce the same density range as in the original, thus a compromise is necessary. A compromise in color match is a very subjective issue and is the primary cause of production rework in the prepress industry.; To reduce the amount of rework due to subjective evaluation of color reproduction an objective model is proposed. In this model a fuzzy set of quality factors will be introduced for the factor space of the separation. Then, a set of importance measures for those quality factors will be presented. These measures will consist of the contribution of each quality factor individually and each possible combination of the factors to the total quality level. Before any decision is made, the synthetic quantitative quality value for the separation is calculated. This measure is then compared to an acceptable quality value experimentally established for each particular customer and printing process. Finally, the installed model is tested in actual production and the results are compared to the conventional subjective evaluation method.