AN IMPROVED PREDICTOR OF COLOURFULNESS IN A MODEL OF COLOR-VISION

An improved predictor of colourfulness in the Hunt 91 model of color v ision is described. A new chroma predictor allows for the effect of th e luminance factor of the background more effectively, and results in more consistent predictions for different viewing conditions. The new colourfulness predictor is obtained by multiplying the new chroma pred ictor by a factor that varies more slowly with the level of adapting l uminance than was the case for the old colourfulness predictor; this r esults in much better predictions, whose coefficients of variation are similar to those that characterize observer consistency. The steps re quired for reversing the model are given in an appendix. (C) 1994 John Wiley & Sons, Inc.