Correlation Between Peak Velocity of Saccades and Susceptibility to Motion Blur

Abstract

A major problem in the subjective evaluation of TV image quality is individual variability among viewers. If observers are not carefully selected for viewing studies, large individual differences in the susceptibility to image blurring result in imprecise evaluations and loss of power to detect statistically significant differences between experimental conditions. In assessments of the picture quality of traditional television, which has a narrow field of view (FOV), observers’ visual acuity (VA) should be screened before the subjective evaluations. For emerging TV systems with wide FOV (Ultra-High-Definition TV: UHDTV), in which objects move quickly relative to the display frame, it is unclear whether screening viewers’ VA is sufficient for selecting viewers to subjectively evaluate moving picture quality or sharpness. Here, we evaluated saccadic eye movement parameters to identify adequate methods to screen participants for studies evaluating UHDTV motion image quality. Each participant's evaluation of two moving pictures were highly correlated, suggesting that participants evaluated sharpness consistently. A significant correlation was observed between the average subjective evaluation score and the peak saccade velocity, but not the VA of each participant. We conclude that each participant has a certain susceptibility to image blur when evaluating moving pictures, and that this susceptibility correlates with the participant's peak saccade velocity. Thus, the objective measure of peak saccade velocity can be used to screen participants for motion picture evaluation studies.