How the eye measures reality and virtual reality

Abstract

Ifvirtual reality systems are to make good on their name, designers must know how people perceive space in natural environments, in photographs, and in cinema. Perceivers understand the layout of a cluttered natural environment through the use of nine or more sources of information, each based on different assumptions--occlusion, height in the visual field, relative size, relative density, aerial perspective, binocular disparities, accommodation, convergence, and motion perspective. The relative utility of these sources at different distances is compared, using their ordinal depth-threshold functions. From these, three classes of space around a moving observer are postulated: personal space, action space, and vista space. Within each, a smaller number of sources act in consort, with different relative strengths. Given the general ordinality of the sources, these spaces are likely to be affine in character, stretching and collapsing with viewing conditions. One of these conditions is controlled by lens length in photography and cinematography or by field-of-view commands in computer graphics. These have striking effects on many of these sources of information and, consequently, on how the layout of a scene is perceived.

The Relative Importance of Pictorial and Nonpictorial Distance Cues for Driver Vision

“…The relative strengths of the various distance cues vary with distance from the observer, with pictorial cues generally preserving their strength at longer distances (Cutting, 1997). This is a fortunate circumstance for the use of camera-based displays in driving.…”

Perception, models, and data: Some comments

“…We will not have a finite set of differential equations that we can list on a couple of pages that will do the job. I think that, in many ways, Cutting (1997) and Kersten (1997) illustrated very nicely why this economical theory is very unlikely. Take Cutting's example of all the different ways in which we use cues to compute information about depth in paintings.…”

“…I put the four papers on visual perception in the order in which we heard from James Cutting (1997), Daniel Kersten (1997), Mary Kaiser (Kaiser & Montegut, 1997), and Jeffrey Mulligan (1997). These are the most hopeful four papers I have heard in psychology in a long time.…”

“…The question is, how much of memory do you think we can simulate, and is it a worthwhile scientific idea to have something to think of in terms of memory comparable to the way we think of vision? So, if we take the kind of examples given herewhether it is Kaiser's (Kaiser & Montegut, 1997) example of Mars, Kersten's (1997) complicated shadow phenomena, or Cutting's (1997) examples of the ways in which painters produce the sense ofdepth---ean we equal them in memory phenomena?…”

Commentary on high-performance computing and human vision I: Perception of visual space

“…The presentations by Cutting (1997) and Kersten (1997) deal with the study of visual space perception. They both focus on the sensitivity that we have to static monocular or pictorial cues for depth and spatial layout.…”