Design and analysis of depth cues on depth perception in interactive mixed reality simulation systems

A stimulus display was devised that enabled us to examine how effectively monkeys and humans can process shading and disparity cues for depth perception. The display allowed us to present these cues separately, in concert and in conflict with each other. An oddities discrimination task was used. Humans as well as monkeys were able to utilize both shading and disparity cues but shading cues were more effectively processed by humans. Humans and monkeys performed better and faster when the two cues were presented conjointly rather than singly. Performance was significantly degraded when the two cues were presented in conflict with each other suggesting that these cues are processed interactively at higher levels in the visual system. The fact that monkeys can effectively utilize depth information derived from shading and disparity indicates that they are a good animal model for the study of the neural mechanisms that underlie the processing of these two depth cues.

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How is Depth Perception Affected by Long-Term Wearing of Left-Right Reversing Spectacles?

Perception ◽

10.1068/p220971 ◽

1993 ◽

Vol 22 (8) ◽

pp. 971-984 ◽

Cited By ~ 7

Author(s):

Makoto Ichikawa ◽

Hiroyuki Egusa

Keyword(s):

Depth Perception ◽

Binocular Disparity ◽

Depth Cues ◽

Directional Relation ◽

Random Dot Stereogram ◽

Binocular Depth

The plasticity of binocular depth perception was investigated. Six subjects wore left-right reversing spectacles continuously for 10 or 11 days. On looking through the spectacles, the relation between the direction of physical depth (convex or concave) and the direction of binocular disparity (crossed or uncrossed) was reversed, but other depth cues did not change. When subjects observed stereograms through a haploscope and were asked to judge the direction of perceived depth, the directional relation between perceived depth and disparity was reversed both in the two line-contoured stereograms and in the random-dot stereogram in the middle of the wearing period, but the normal relation often returned late in the wearing period. When subjects observed two objects while wearing the spectacles and were asked which appeared the nearer, veridical depth perception increased as the wearing-time passed. These results indicate that the visual transformation reversing the direction of binocular disparity causes changes both in binocular stereopsis and in processes integrating different depth cues.

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Depth Perception in Alzheimer's Disease

Perceptual and Motor Skills ◽

10.2466/pms.1996.83.3.987 ◽

1996 ◽

Vol 83 (3) ◽

pp. 987-995 ◽

Cited By ~ 30

Author(s):

Mario F. Mendez ◽

Monique M. Cherrier ◽

Robert S. Meadows

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Depth Perception ◽

Motion Parallax ◽

Relative Size ◽

Depth Cues ◽

Visuospatial Deficits ◽

Visuospatial Functions ◽

Monocular Depth ◽

Global Stereopsis

Abnormal depth perception contributes to visuospatial deficits in Alzheimer's disease. Disturbances in stereopsis, motion parallax, and the interpretation of static monocular depth cues may result from neuropathology in the visual cortex. We evaluated 15 patients with mild Alzheimer's disease and 15 controls matched for age, sex, and education on measures of local stereopsis (stereoscopic testing), global stereopsis (random dots), motion parallax (Howard-Dolman apparatus), and monocular depth perception by relative size, interposition, and perspective. Compared to controls, the patients were significantly impaired in over-all depth perception. This impairment was largely due to disturbances in local stereopsis and in the interpretation of depth from perspective, independent of other visuospatial functions. Patients with Alzheimer's disease have disturbed interpretation of monocular as well as binocular depth cues. This information could lead to optic interventions to improve their visual depth perception.

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Dynamic Occlusion and Motion Parallax in Depth Perception

Perception ◽

10.1068/p170255 ◽

1988 ◽

Vol 17 (2) ◽

pp. 255-266 ◽

Cited By ~ 26

Author(s):

Hiroshi Ono ◽

Brian J Rogers ◽

Masao Ohmi ◽

Mika E Ono

Keyword(s):

Relative Motion ◽

Depth Perception ◽

Motion Parallax ◽

Three Dimensional ◽

Depth Order ◽

Depth Cues ◽

Small Depth ◽

Stationary Observer ◽

Depth Separation ◽

Condition B

Random-dot techniques were used to examine the interactions between the depth cues of dynamic occlusion and motion parallax in the perception of three-dimensional (3-D) structures, in two different situations: (a) when an observer moved laterally with respect to a rigid 3-D structure, and (b) when surfaces at different distances moved with respect to a stationary observer. In condition (a), the extent of accretion/deletion (dynamic occlusion) and the amount of relative motion (motion parallax) were both linked to the motion of the observer. When the two cues specified opposite, and therefore contradictory, depth orders, the perceived order in depth of the simulated surfaces was dependent on the magnitude of the depth separation. For small depth separations, motion parallax determined the perceived order, whereas for large separations it was determined by dynamic occlusion. In condition (b), where the motion parallax cues for depth order were inherently ambiguous, depth order was determined principally by the unambiguous occlusion information.

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Effects of Time Delay on Depth Perception via Head-Motion Parallax in Virtual Environment Systems

Presence Teleoperators & Virtual Environments ◽

10.1162/105474600300040439 ◽

2000 ◽

Vol 9 (6) ◽

pp. 638-647 ◽

Cited By ~ 3

Author(s):

Hanfeng Yuan ◽

W. L. Sachtler ◽

Nat Durlach ◽

Barbara Shinn-Cunningham

Keyword(s):

Time Delay ◽

Virtual Environment ◽

Depth Perception ◽

Head Movement ◽

Time Delays ◽

Motion Parallax ◽

Head Motion ◽

Depth Cues ◽

Random Dot Patterns

Experiments were conducted to determine how the ability to detect and discriminate head-motion parallax depth cues is degraded by time delays between head movement and image update. The stimuli consisted of random-dot patterns that were programmed to appear as one cycle of a sinusoi dal grating when the subject's head moved. The results show that time delay between head movement and image update has essentially no effect on the ability to discrimi nate between two such gratings with different depth char acteristics when the delay is less than or equal to roughly 265 ms.

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Depth Perception of Interfering Periodic Patterns: A Possible Contribution to Disorientation on Escalators

Perception ◽

10.1068/p210747 ◽

1992 ◽

Vol 21 (6) ◽

pp. 747-752 ◽

Cited By ~ 3

Author(s):

Roger C Munck-Fairwood

Keyword(s):

Interference Pattern ◽

Depth Perception ◽

Apparent Depth ◽

Periodic Patterns ◽

Depth Cues ◽

The Many

Incongruous and illusory depth cues, arising from ‘interference patterns’ produced by overlapping linear grids at the edges of escalator treads, may contribute to the disorientation experienced by some escalator users, which in turn may contribute to the causes of some of the many escalator accidents which occur. The apparent depth of the interference pattern from the viewer is analysed in terms of the cues deriving from size and viewer motion. Both of these cues support the depth of the target being infinite. Preliminary observations are reported which confirm this analysis. Remedies for the problem are suggested. The possible contribution of this illusion to disorientation on escalators, due to misjudgment of depth, is compared with another recently reported factor which is due to stereoscopic miscorrespondence of periodic targets.

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Depth Perception in Pandora's Box and Size Illusion: Evolution with Age

Perception ◽

10.1068/p120177 ◽

1983 ◽

Vol 12 (2) ◽

pp. 177-185 ◽

Cited By ~ 6

Author(s):

Jacques Chevrier ◽

André Delorme

Keyword(s):

Depth Perception ◽

Relative Position ◽

Linear Perspective ◽

Pictorial Stimulus ◽

Texture Gradient ◽

Familiar Size ◽

Depth Cues ◽

Pictorial Depth

The aim of the experiment was to study the evolution with age (6, 8, 11 and 14 years) of pictorial depth perception in Pandora's box and to compare it with the evolution of size illusion with the same subjects and the same pictorial backgrounds. In addition to familiar size and relative position, each pictorial stimulus contained one or more of the following depth cues: linear perspective, texture gradient, and interposition. The two kinds of measurements produced different results. Size illusions, although present, did not vary with age but increased with the number of cues. Estimates of distance in Pandora's box increased with age and varied according to the type of cue present: texture gradient seemed to be critical to the amount of depth perceived. The correlation between size adjustments and distance adjustments was significant only for the two oldest groups of subjects (11 and 14 years).

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