The Role of Contrast in the Perceived Depth of Monocular Imagery

Allan G. Rempel¹, Wolfgang Heidrich¹, Rafał Mantiuk²

(1) The University of British Columbia, (2) Bangor University

APGV 2011 one-page abstract PDF

Abstract

Since high dynamic range (HDR) displays have been shown at conferences, they have been confused with 3D displays by some observers. In this paper, we explore this perceptual connection by conducting a series of experiments to examine the effect that contrast has on depth perception. In particular, we consider the contrast both of large-scale features and of small-scale features, both independently and in concert. We found that in each of three experiments, subjects perceived increases in contrast to correspond with increases in perceived depth. Our findings indicate that we can simulate sensations of depth by manipulating contrast, particularly that of highlights within images, and that modern high-contrast displays can simulate greater sensations of depth.

Detailed results of experiments

The following plots show the detailed results of Experiments 1 and 2. Each experiment is broken down into two parts: random-dot disk images and leaf texture images. For each part there are 6 plots, which are all arranged on one line.

The first two plots in a line show how perceived depth varies with texture contrast at different levels of area luminance and background luminance, and they correlate with the two plots in Figure 4 (p. 692) in Ichihara et al. as well as the left plot of Figure 2 of our paper.

The next two plots (third and fourth) in a line show how perceived depth varies with area contrast (Michelson) at different levels of texture contrast and background luminance, and they correlate with the right plot in Figure 2 of our paper. They also correlate with Figure 5 of our paper, except that the Michelson contrast calculation is replaced with a contrast ratio calculation. Plots of this type do not appear in Ichihara et al.

The fifth plot in a line shows how the effect of texture contrast on depth is stronger at low levels of area contrast and weaker at high levels. It correlates with Figure 5 in Ichihara et al. as well as the left plot of Figure 3 of our paper, and with Figure 6 in our paper except with the Michelson contrast calculation replaced with contrast ratio.

The sixth and last plot in a line shows how the effect of area contrast on depth varies with texture contrast, as well as the difference between positive area contrast and negative area contrast, and it correlates with the right plot of Figure 3 of our paper. Plots of this type do not appear in Ichihara et al.