A psychophysical study of improvements in motion-image quality by using high frame rates

The ideal frame rate for the highest motion-image quality with respect to blur and jerkiness is presented. In order to determine the requirements for avoiding these impairments, motion images from a high-speed camera and computer graphics were combined with a high-speed display to perform a psychophysical evaluation. The camera, operating at 1000 fps, and image processing were used to simulate various frame rates and shutter speeds, and a 480-Hz CRT display was used to present motion images simulating various frame rates and time characteristics of the display. Subjects were asked to evaluate the difference in quality between motion images at various frame rates. A frame rate of 480 fps was chosen to be an appropriate reference frame rate that, as a first estimation, enables coverage up to the human-dynamic-resolution (HDR) limit based on another experiment using real moving charts. The results show that a frame rate of 120 fps provides good improvement compared to that of 60 fps, and that the maximum improvement beyond which evaluation is saturated is found at about 240 fps for representative standard-resolution natural images.