Abstract
The area of interest (AOI) on a video frame may be necessary: (1) to develop a television magnifying aid for people with low vision; (2) to implement some data compression schemes; and (3) to transform images for rendering on devices with small display areas. We determined the AOI in video frames by recording and analyzing the eye movements of 4 groups (Young Male, Young Female, Older Male and Older Female) of 5 subjects each while they watched 5–10 minute video segments of 6 movies. Within group AOI coincidence (temporal and spatial) was marked on a frame if valid eye position data was available for at least 4 of the 5 subjects and the bivariate contour ellipse area (BVCA)(k=1, P=63.2%) was < 9 deg2 (the screen was 27×15 deg2). Analysis of the male group's data on 4 movies only was completed to date. Within group, temporal coincidence occurred for about 50% of all frames in each movie (chance would have been < 25%). The within-group AOI coincidence rate was 25%. Between the older and younger age groups, the AOI were < 3 deg apart at least 60% of the time. This was not due to the AOI being clustered around the center of the screen since only 27% of the time they were within 3 deg of the center of the screen. For a < 25 deg2 BVCA, the AOI were within 5deg of the screen center at least 70% of the time accounting for much of the 84% of the time that the AOI were within 5 deg of each other. Conclusion: Across the two groups the AOIs were within 2% of the screen area for a minimum of 15% of frames (where temporal coincidence chance rate was 6%). The high level of AOI coincidence within and across age groups, even away from the screen's center, suggests that a single AOI might be appropriate for varied audiences in many applications. Analysis of the frames where group AOIs differ might be of interest in determining what type of visual or content categories would account for such difference between gender and age group AOIs.
Support: EY05957and EY12890