Title: Perceived Image Contrast and Observer Preference Ii. Empirical Modeling of Perceived Image Contrast and Observer Preference Data

Psychophysical experimentation was performed on the perceived contrast of color images and its effect on observer preference. Goals of this research included the following: investigation into the roles of image lightness, chroma and sharpness manipulations on perceived image contrast; modeling the perception of image contrast with physical image parameters; the relation of perceived contrast of an image to the most preferred version of that image; and the generation of a large-scale image contrast data set for later use in image difference/quality metric development. These goals were undertaken by administration of soft-copy paired-comparison experiments of perceived image contrast and observer preference. These tests were performed over four months, by more than seventy observers. Perceived image contrast was determined to be scalable with respect to lightness, chroma, and sharpness manipulations. Perceived image contrast scales were image independent between five pictorial