Abstract
We investigated whether temporal changes of the scene caused by lateral motion of the observer and image differences between the eyes affect the perception of surface gloss. The stimulus was a computer-generated display which simulated a glossy and bumpy surface. The subjects viewed the stimulus through the stereo goggles. In the head-motion experiment, the subjects moved their heads back-and-forth laterally observing the stimulus monocularly or binocularly. The test stimulus changed temporally in luminance of specular highlights and in position on the two-dimensional computer monitor depending on the subjects' head positions (motion parallax) so that the surface was simulated to be stationary in the three-dimensional space. The reference stimulus did not change on the monitor. In the stereo-viewing experiment, the test stimulus differed between the eyes in luminance of specular highlights and in position (binocular disparity) while the reference stimulus did not differed between the eyes in luminance or position (zero disparity). In both experiments, the subjects rated the glossiness of the reference stimulus compared with the test stimulus. The subjects also adjusted the specular reflectance of the reference so that the glossiness of the two stimuli appeared equal. The rated glossiness of the reference stimulus was lower than that of the test stimulus while the matched reflectance of the reference stimulus was larger than that of the test. The results suggest that both temporal changes of the scene caused by lateral motion of the observer and image differences between the eyes enhance the strength of perceived gloss.