Effect of TV's physical controls on psychological dimensions for still image quality evaluation

Abstract

The purpose of this study is to find out changes in the psychological dimensions that evaluate the image quality of TV still images as to the various levels of the TV's physical controls (e.g. contrast, brightness, hue (tint), saturation (color), color temperature and gamma). Results of factor analysis on all of the psychophysical data showed that there are slight differences in psychological dimensions according to each TV program's scenes. Psychophysical test was performed with 5 scenes for the evaluation of the image quality of an LCD-TV, using the evaluation scales for each TV programs. Five scenes from major TV programs-the news, history drama, sports, soap drama, and documentaries-were selected and TV physical controls with 3~5 levels were used to produce a total of 120 different still pictures. These still images were then shown to 24 male and female university students in their twenties. The resulting factor analysis on all of the psychophysical data showed that there are slight differences in psychological dimensions according to each TV program's scenes. Psychological dimensions can be roughly divided into 3 categories-SSE (the scene-specific emotion). Sensation, and Pleasant-Unpleasantness. Changes in the color according to changes in the set levels of each TV physical controls showed that each program's scenes had different effects on the psychological dimensions. Maximization of the dynamic range was particularly found also to maximize all psychological reactions for all TV program scenes. Changes in saturation and hue led to different reactions in the 3 psychological dimensions for all scenes. On the other hand, changes in gamma and color temperature resulted in a weak reactions of psychological dimensions, and the reaction varied according to the scenes. © 2008 Society for Imaging Science and Technology.