DOCSLIB.ORG

Perceiving Self-Motion in Depth: the Role of Stereoscopic Motion and Changing-Size Cues

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Perceiving Self-Motion in Depth: the Role of Stereoscopic Motion and Changing-Size Cues Perception & Psychophysics 1996,58 (8), JJ68-JJ76 Perceiving self-motion in depth: The role of stereoscopic motion and changing-size cues STEPHEN PALMISANO University ofNew South Wales, Kensington, New South Wales, Australia During self-motions, different patterns of optic flow are presented to the left and right eyes. Previ­ ous research has, however, focused mainly on the self-motion information contained in a single pattern of optic flow. The present experiments investigated the role that binocular disparity plays in the visual perception of self-motion, showing that the addition of stereoscopic cues to optic flow significantly im­ proves forward linear vection in central vision. Improvements were also achieved by adding changing­ size cues to sparse (but not dense) flow patterns. These findings showedthat assumptions in the head­ ing literature that stereoscopic cues facilitate self-motion only when the optic flow has ambiguous depth ordering do not apply to vection. Rather, it was concluded that both stereoscopic and changing­ size cues provide additional motion-in-depth information that is used in perceiving self-motion. Ofall the senses known to be involved in self-motion During self-motions, different patterns of optic flow perception-the vestibular, auditory, somatosensory, pro­ are presented to the left and right eyes (due to the sepa­ prioceptive, and visual systems-visionappears to play the ration ofthe eyes and their different angles ofregard; see dominant role (Benson, 1990; Howard, 1982). This is Figure 1). Theorists have, however, generally focused only demonstrated by the fact that compelling illusions of on the motion-perspective information contained in a sin­ self-motion can be induced by visual information alone. gle pattern, assuming that this is sufficient to accurately For example, when subjects are placed in a "swinging perceive self-motion (e.g., Gibson, 1950; Gibson et a1., room," where the walls and ceiling swing back and forth, 1955; Gordon, 1965; Heeger & Jepson, 1990; Koen­ they soon experience the illusion that they themselves are derink, 1990; Koenderink & van Doorn, 1981, 1987; Lee, swaying (Lee & Aronson, 1974; Lee & Lishman, 1975; 1980; Longuet-Higgins & Prazdny, 1980; Nakayama & Lishman & Lee, 1973). Similarly, when subjects are placed Loomis, 1974). Accordingly, the role that stereoscopic in­ inside a "rotating drum," a rotating cylinder with a pat­ formation plays in self-motion perception has received lit­ terned inner wall, they quickly experience an illusion of tle attention. self-rotation (Brandt, Dichgans, & Koenig, 1973; Mach, Recently, however, van den Berg and Brenner (1994b) 1875). These illusions occur because the swinging room have shown that, in some situations, heading perception and the rotating drum duplicate the visual stimulation (one aspect of self-motion perception) can be improved that normally occurs during real self-motions. by the addition ofstereoscopic cues. Their earlier research A major visual stimulus for self-motion perception is had found that heading estimates were error prone in the optic flow or the temporal change in the pattern of light presence of motion noise, when displays simulated ob­ intensities at the moving point of observation (Gibson, server motion through a cloud ofdots (van den Berg, 1992; 1966; Warren, Morris, & Kalish, 1988). Gradients ofop­ van den Berg & Brenner, 1994a). They subsequently dis­ tical velocity contain several potential sources ofinforma­ covered that when binocular disparities were added to tion about observer motion through three-dimensional these "cloud" displays, heading estimates became up to space (Gibson, Olum, & Rosenblatt, 1955). There is the four times more resistant to noise. Changing disparity was perspective change in location ofobjects in the optic array not essential for this improved heading performance: Sub­ (which shall be referred to as motion perspective) and jects performed just as well when each dot had a fixed their optical expansion/contraction (which shall be re­ retinal disparity for the duration of the display (in this ferred to as changing size). 1 case, only motion perspective simulated self-motion in depth). Van den Berg and Brenner concluded that stereo­ scopic vision improves heading perception indirectly by Portions of this research were presented at the 1995 Association for providing the depth order ofthe objects in the flow (rather Research in Vision and Ophthalmology Conference held in Fort Lau­ derdale, FL. The author thanks Barbara Gillam and Shane Blackburn than by providing additional motion in depth informa­ for their feedback and suggestions regarding this article and Keith tion). Furthermore, they argued that other depth cues, Llewellyn for the loan of his equipment. The author is also grateful to such as occlusion or texture gradients, might improve Myron Braunstein, George Andersen, and two anonymous reviewers for heading judgments in a similar fashion. their insightful comments on an earlier version of this article. Corre­ spondence should be addressed to S. Palmisano, School ofPsychology, There is reason to believe that stereoscopic informa­ University ofNew South Wales, POB I, Kensington, NSW 2033, Aus­ tion might also enhance the subjective experience ofself­ tralia (e-mail: [email protected]). motion, known as vection. In their study, Andersen and Copyright 1996 Psychonomic Society, Inc. 1168 PERCEIVING SELF-MOTION IN DEPTH 1169 • • •• • • ••• • •• • iii·.·· • • ...... ',. • .. .......• .. .." .. ' " . '. .. .. ..... ........ •... ·;····~::r·~·.·· ' ' .. " -,' .. ' . ... " .. •• " .. .... : ~ .. ....-. '. .... .. ..' • •• • •••• '. •.. .. '. .. : . ... .' . , _ '.' .•. " ... .•.... .. .. • • • ..- • Figure 1. A stereogram representing the different optic arrays presented to the left and right eyes at anyone point in time (converge in order to fuse the two images). Braunstein (1985) simulated forward self-motion through z-axis toward the observer (the projection plane and the observer's a three-dimensional cloud of dots. The perceived three­ viewpoint remained fixed). A constant density was maintained by dimensionality of these displays was manipulated by al­ replacing each object as it disappeared from view at the opposite tering the motion-based cues to self-motion in depth. They end of space (a simulated distance of 20 m). All displays had a frame rate of60 Hz. found that the more three-dimensional the inducing dis­ Stereoscopic displays presented horizontally disparate patterns plays appeared, the stronger the vection in central vision. of optic flow to the two eyes. This was achieved by presenting the Although Andersen and Braunstein did not investigate disparate views in different colors on a single display, which was the role ofstereoscopic cues on vection, an argument can then viewed through red--eyan anaglyph glasses. To fuse these dis­ be mounted on the basis oftheir data. Ifit is assumed that plays, the subjects needed to verge behind the screen. Thus, prior to adding stereoscopic information to inducing displays their presentation, the subjects were shown a pair ofvertically dis­ placed nonius lines (one red, one cyan) separated by a disparity rep­ makes them appear more three-dimensional, it follows resenting the farthest distance simulated by the display? (Hebbard, that such displays might produce stronger vection (in 1962; Mitchell & Ellerbrock, 1955). They then had to alter their central vision) than those with motion perspective alone. convergence until the nonius targets were aligned, before triggering The present experiments investigated whether the ad­ the stereoscopic display. dition ofstereoscopic information to optic flow would in­ Nonstereoscopic displays were oftwo types. Monocularly viewed crease forward linear vection in central vision. They were displays presented a single pattern ofoptic flow to one eye. Binoc­ ularly viewed nonstereoscopic displays presented the same pattern designed to determine whether any such increases were of moving objects to both eyes (producing slightly different flow due to improved depth ordering or to additional motion patterns due to the different positions ofthe two eyes). Prior to the in depth information. In addition, a further two experi­ monocularly viewed displays, the subjects were told to lower an eye ments examined whether another source of motion in patch over the right eye. Before binocularly viewed nonstereoscopic depth information (changing size) could also produce an displays, the subjects were presented with a pair ofnonius lines set advantage for vection. at zero disparity (since the subjects had to verge on the screen to view these displays). After lowering the eye patch or verging on the screen, the subjects then triggered the nonstereoscopic display. GENERAL METHOD EXPERIMENT 1 Subjects The subjects were students in an introductory psychology course who received course credit for their participation. All had normal Experiment I compared the vection induced by stereo­ or corrected-to-normal vision and had no previous laboratory ex­ scopic and monocularly viewed displays simulating self­ perience with illusions ofself-motion. Different subjects were used motion in depth. In the case of stereoscopic displays, in each ofthe four experiments. vergence was consistent with the presence of three­ dimensional, virtual space behind the screen. Nonstereo­ Visual Displays All displays simulated forward self-motion through a cloud of scopic displays were viewed monocularly to remove any randomly positioned
Load more

Recommended publications
  • Specific Eye Conditions with Corresponding Adaptations/Considerations
    Specific Eye Conditions with Corresponding Adaptations/Considerations # Eye Condition Effect on Vision Adaptations/Considerations 1 Achromotopsia colors are seen as shades of grey, tinted lenses, reduced lighting, alternative nystagmus and photophobia improve techniques for teaching colors will be with age required 2 Albinism decreased visual acuity, photophobia, sunglasses, visor or cap with a brim, nystagmus, central scotomas, strabismus reduced depth perception, moving close to objects 3 Aniridia photophobia, field loss, vision may tinted lenses, sunglasses, visor or cap with fluctuate depending on lighting brim, dim lighting, extra time required to conditions and glare adapt to lighting changes 4 Aphakia reduced depth perception, inability to sunglasses, visor or cap with a brim may accommodate to lighting changes be worn indoors, extra time required to adapt to lighting changes 5 Cataracts poor color vision, photophobia, visual bright lighting may be a problem, low acuity fluctuates according to light lighting may be preferred, extra time required to adapt to lighting changes 6 Colobomas photophobia, nystagmus, field loss, sunglasses, visor or cap with a brim, reduced depth perception reduced depth perception, good contrast required 7 Color Blindness difficulty or inability to see colors and sunglasses, visor or cap with a brim, detail, photophobia, central field reduced depth perception, good contrast scotomas (spotty vision), normal required, low lighting may be preferred, peripheral fields alternative techniques for teaching colors
    [Show full text]
  • Two Eyes See More Than One Human Beings Have Two Eyes Located About 6 Cm (About 2.4 In.) Apart
    ivi act ty 2 TTwowo EyesEyes SeeSee MoreMore ThanThan OneOne OBJECTIVES 1 straw 1 card, index (cut in half widthwise) Students discover how having two eyes helps us see in three dimensions and 3 pennies* increases our field of vision. 1 ruler, metric* The students For the class discover that each eye sees objects from a 1 roll string slightly different viewpoint to give us depth 1 roll tape, masking perception 1 pair scissors* observe that depth perception decreases *provided by the teacher with the use of just one eye measure their field of vision observe that their field of vision decreases PREPARATION with the use of just one eye Session I 1 Make a copy of Activity Sheet 2, Part A, for each student. SCHEDULE 2 Each team of two will need a metric ruler, Session I About 30 minutes three paper cups, and three pennies. Session II About 40 minutes Students will either close or cover their eyes, or you may use blindfolds. (Students should use their own blindfold—a bandanna or long strip VOCABULARY of cloth brought from home and stored in their science journals for use—in this depth perception and other activities.) field of vision peripheral vision Session II 1 Make a copy of Activity Sheet 2, Part B, for each student. MATERIALS 2 For each team, cut a length of string 50 cm (about 20 in.) long. Cut enough index For each student cards in half (widthwise) to give each team 1 Activity Sheet 2, Parts A and B half a card. Snip the corners of the cards to eliminate sharp edges.
    [Show full text]
  • Binocular Vision
    BINOCULAR VISION Rahul Bhola, MD Pediatric Ophthalmology Fellow The University of Iowa Department of Ophthalmology & Visual Sciences posted Jan. 18, 2006, updated Jan. 23, 2006 Binocular vision is one of the hallmarks of the human race that has bestowed on it the supremacy in the hierarchy of the animal kingdom. It is an asset with normal alignment of the two eyes, but becomes a liability when the alignment is lost. Binocular Single Vision may be defined as the state of simultaneous vision, which is achieved by the coordinated use of both eyes, so that separate and slightly dissimilar images arising in each eye are appreciated as a single image by the process of fusion. Thus binocular vision implies fusion, the blending of sight from the two eyes to form a single percept. Binocular Single Vision can be: 1. Normal – Binocular Single vision can be classified as normal when it is bifoveal and there is no manifest deviation. 2. Anomalous - Binocular Single vision is anomalous when the images of the fixated object are projected from the fovea of one eye and an extrafoveal area of the other eye i.e. when the visual direction of the retinal elements has changed. A small manifest strabismus is therefore always present in anomalous Binocular Single vision. Normal Binocular Single vision requires: 1. Clear Visual Axis leading to a reasonably clear vision in both eyes 2. The ability of the retino-cortical elements to function in association with each other to promote the fusion of two slightly dissimilar images i.e. Sensory fusion. 3. The precise co-ordination of the two eyes for all direction of gazes, so that corresponding retino-cortical element are placed in a position to deal with two images i.e.
    [Show full text]
  • Collaborative Treatment for Vision After TBI
    Collaborative Treatment for Vision After TBI Tom Wilson, OD, COVD Terri Cassidy, OTR, CDRS Vision is Primary • Human vision is a complex process that involves the coordinated efforts of both the eyes and the brain. • We use central vision (focal) to see detail. • We use peripheral vision (ambient) to inform us of movement or a direction we should point our eyes. • Even if we feel like our eyes (and brain) are not giving us accurate information – we believe our eyes. 2 Case Study 1 56 y/o woman involved in a motor vehicle crash. She was able to walk and talk. MRI was negative. Not long after she notices symptoms of not being able to read correctly, headaches, motion sickness is much worse than normal, she can’t go back to work on the computer, she is very tentative about driving. Her eye doctor tells her that her eyes are fine, it must be her medications. Finally she is referred to Dr. Wilson who does an evaluation and refers her to vision rehab with OT. Presentation Title – Date (month #, ####) 3 Evaluation Neuro-optometric Assessment • Eye health • Binocular Vision • Prism evaluation • Function Occupational Therapy Vision Assessment • Goal of OT is to improve the client’s level of performance in a needed ADL. • Deficiencies in visual processing are significant to the OT Process if they interfere with occupational performance – doing the tasks that she wants and needs to do. Presentation Title – Date (month #, ####) 4 Evaluation Results OD Finds: OT Finds: Characteristics of Post Trauma Pt is not able to work more than 2 Vision Syndrome
    [Show full text]
  • Motion-In-Depth Perception and Prey Capture in the Praying Mantis Sphodromantis Lineola
    © 2019. Published by The Company of Biologists Ltd | Journal of Experimental Biology (2019) 222, jeb198614. doi:10.1242/jeb.198614 RESEARCH ARTICLE Motion-in-depth perception and prey capture in the praying mantis Sphodromantis lineola Vivek Nityananda1,*, Coline Joubier1,2, Jerry Tan1, Ghaith Tarawneh1 and Jenny C. A. Read1 ABSTRACT prey as they come near. Just as with depth perception, several cues Perceiving motion-in-depth is essential to detecting approaching could contribute to the perception of motion-in-depth. or receding objects, predators and prey. This can be achieved Two of the motion-in-depth cues that have received the most using several cues, including binocular stereoscopic cues such attention in humans are binocular: changing disparity and as changing disparity and interocular velocity differences, and interocular velocity differences (IOVDs) (Cormack et al., 2017). monocular cues such as looming. Although these have been Stereoscopic disparity refers to the difference in the position of an studied in detail in humans, only looming responses have been well object as seen by the two eyes. This disparity reflects the distance to characterized in insects and we know nothing about the role of an object. Thus as an object approaches, the disparity between the stereoscopic cues and how they might interact with looming cues. We two views changes. This changing disparity cue suffices to create a used our 3D insect cinema in a series of experiments to investigate perception of motion-in-depth for human observers, even in the the role of the stereoscopic cues mentioned above, as well as absence of other cues (Cumming and Parker, 1994).
    [Show full text]
  • 20/20 VISION Part I: Eyesight, Perception and Vision
    20/20 VISION Part I: Eyesight, perception and vision In this first part of our three-part exploration of 20/20 vision, we are going to look at our physical eyes and how they work. Then we will explore perception and how the brain actually converts all that sensory information into images. Finally, we will look at some of the techniques for improving our vision naturally and ask if these really work. 20/20 vision is a term used to express normal visual acuity (the clarity or sharpness of vision) measured at a distance of 20 feet. ... If you have 20/100 vision, it means that you must be as close as 20 feet to see what a person with normal vision can see at 100 feet. Having 20/20 vision does not necessarily mean you have perfect vision. 20/20 vision only indicates the sharpness or clarity of vision at a distance. Other important vision skills, including peripheral awareness or side vision, eye coordination, depth perception, focusing ability and colour vision, contribute to your overall visual ability. Some people can see well at a distance but are unable to bring nearer objects into focus. This condition can be caused by hyperopia (far-sightedness) or presbyopia (loss of focusing ability). Others can see items that are close but cannot see those far away. This condition may be caused by myopia (near-sightedness). Is it possible to see better than 20/20? Yes, it's indeed possible to have sharper than 20/20 vision. In fact, most people with young, healthy eyes are capable of identifying at least some of the letters on the 20/15 line or even smaller letters on the Snellen chart.
    [Show full text]
  • An Adaptive Blur in Peripheral Vision to Reduce Visual Fatigue in Stereoscopic Vision
    ©2016 Society for Imaging Science and Technology DOI: 10.2352/ISSN.2470-1173.2016.5.SDA-438 An Adaptive Blur in Peripheral Vision to Reduce Visual Fatigue in Stereoscopic Vision David AURAT; MINES ParisTech, PSL Research University, Centre for robotics; Paris; France Laure LEROY; Paris 8 University; Saint-Denis; France Olivier HUGUES; MINES ParisTech, PSL Research University, Centre for robotics; Paris; France Philippe FUCHS; MINES ParisTech, PSL Research University, Centre for robotics; Paris; France Abstract Related Work For some years, a lot of Stereoscopic 3D contents have As we described previously, the accommodation ver- been released. Even if the depth sensation is realistic, it gence conflict is a cause of eye strain in stereoscopic 3D is still not perfect and uncomfortable. The objective of our vision. A lot of people have studied this conflict. Some work is to use the gaze of the user to bring closer artificial people created multi-focal system to limits the distance be- vision and natural vision to increase the precision of the per- tween the convergence point and the accommodation point ception and decrease visual fatigue. For example, a differ- like Hoffman et al. [4]. They concluded that multi-focal ence in artificial vision is the accommodation point and the system decrease viewer fatigue and discomfort, increase convergence point of the eye. In natural vision, these points stereoacuity, reduce time to identify a stereo stimulus and are the same whereas in artificial vision event if the con- reduce distortion in perceived depth. Neveu et al. [1] vergence point is on the looked object, the accommodation showed that beginning with a small conflict and increasing point remains on the screen.
    [Show full text]
  • Vision Challenges with Vestibular Disorders
    5018 NE 15TH AVE · PORTLAND, OR 97211 · FAX: (503) 229-8064 · (800) 837-8428 · [email protected] · VESTIBULAR.ORG Vision Challenges with Vestibular Disorders By Michael C. Schubert, PT, PhD with the Vestibular Disorders Association, and contributions by Kenneth Ciuffreda, O.D., PhD, FCOVD-A and Allen H. Cohen, O.D., FCOVD A common complaint for people with patients consult with an optometrist who vestibular disorders is that they have specializes in Neuro-optometric difficulty with their vision. They may Rehabilitation. The neuro-optometric experience problems focusing on an object evaluation specifically assesses the visual, or perceive that objects are moving from ocular motor and focusing skills important side to side or revolving around them for stabilizing the sensory motor (vertigo). They may see their visual field components of the vestibule-ocular reflex jiggle or bounce during head motion (or “VOR”). (oscillopsia) or have double vision (diplo- pia). When they hold their heads still, HOW DO VESTIBULAR DISORDERS these visual instability problems might AFFECT VISION? resolve. The vestibular system and the visual Many people with vestibular disorders system coordinate with each other through consult an eye care professional due to brain pathways in order to control visual their visual symptoms. The typical eye fixation. The ‘ear to eye’ connection is examination is done while the patient’s known as the vestibulo-ocular reflex head is resting against a head rest, (VOR). The VOR has a critical role of thereby reducing the head motion, which keeping the eyes still during head motion. may mask the visual symptoms. With a This is known as gaze stability.
    [Show full text]
  • Stereoscopic Viewing Enhances Visually Induced Motion Sickness
    Behrang Keshavarz* Stereoscopic Viewing Enhances Heiko Hecht Department of General Visually Induced Motion Sickness Experimental Psychology but Sound Does Not Johannes Gutenberg-University 55099 Mainz, Germany Abstract Optic flow in visual displays or virtual environments often induces motion sickness (MS). We conducted two studies to analyze the effects of stereopsis, background sound, and realism (video vs. simulation) on the severity of MS and related feelings of immersion and vection. In Experiment 1, 79 participants watched either a 15-min-long video clip taken during a real roller coaster ride, or a precise simulation of the same ride. Additionally, half of the participants watched the movie in 2D, and the other half in 3D. MS was measured using the Simulator Sickness Questionnaire (SSQ) and the Fast Motion Sickness Scale (FMS). Results showed a significant interaction for both variables, indicating highest sickness scores for the real roller coaster video presented in 3D, while all other videos provoked less MS and did not differ among one another. In Experiment 2, 69 subjects were exposed to a video captured during a bicycle ride. Viewing mode (3D vs. 2D) and sound (on vs. off) were varied between subjects. Response measures were the same as in Experiment 1. Results showed a significant effect of stereopsis; MS was more severe for 3D presentation. Sound did not have a significant effect. Taken together, stereoscopic viewing played a crucial role in MS in both experiments. Our findings imply that stereoscopic videos can amplify visual dis- comfort and should be handled with care. 1 Introduction Over the past decades, the technological progress in entertainment sys- tems has grown rapidly.
    [Show full text]
  • Effect of Stroboscopic Vision Training on Dynamic Visual Acuity Scores: Nike Vapor Strobe® Eyewear
    Utah State University DigitalCommons@USU All Graduate Plan B and other Reports Graduate Studies 5-2013 Effect of Stroboscopic Vision Training on Dynamic Visual Acuity Scores: Nike Vapor Strobe® Eyewear Joshua Holliday Utah State University Follow this and additional works at: https://digitalcommons.usu.edu/gradreports Recommended Citation Holliday, Joshua, "Effect of Stroboscopic Vision Training on Dynamic Visual Acuity Scores: Nike Vapor Strobe® Eyewear" (2013). All Graduate Plan B and other Reports. 262. https://digitalcommons.usu.edu/gradreports/262 This Report is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Plan B and other Reports by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. Utah State University DigitalCommons@USU All Graduate Plan B and other Reports Graduate Studies 4-2013 Effect of Stroboscopic Vision Training on Dynamic Visual Acuity Scores: Nike Vapor Strobe® Eyewear Joshua Holliday Follow this and additional works at: http://digitalcommons.usu.edu/gradreports Recommended Citation Holliday, Joshua, "Effect of Stroboscopic Vision Training on Dynamic Visual Acuity Scores: Nike Vapor Strobe® Eyewear" (2013). All Graduate Plan B and other Reports. Paper 262. This Report is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Plan B and other Reports by an authorized administrator of DigitalCommons@USU.
    [Show full text]
  • Perceived Speed of Motion in Depth Is Reduced in the Periphery
    Vision Research 40 (2000) 3507–3516 www.elsevier.com/locate/visres Perceived speed of motion in depth is reduced in the periphery K. Brooks *, G. Mather Experimental Psychology, Biology School, Uni6ersity of Sussex, Brighton BN19QG, UK Received 24 February 1999; received in revised form 30 November 1999 Abstract The perceived speed of motion in depth (MID) for a monocularly visible target was measured in central and peripheral vision using a 2AFC speed discrimination task. Only binocular cues to MID were available: changing disparity and interocular velocity difference (IOVD). Perceived speed for monocular lateral motion and perceived depth for static disparity were also assessed, again in both central and peripheral vision. The purpose of the experiment was to assess the relative contributions of changing disparity and IOVD cues to the perceived speed of stereomotion. Although peripheral stimuli appeared to lie at approximately the same depth as their central counterparts, their apparent speed was reduced. Monocular/lateral and binocular/MID speeds were reduced to a similar extent. It seems that reduced apparent monocular speed leads to reduced perceived MID speed, despite the fact that the disparity system appears to be unaffected. These results suggest that the IOVD cue makes a significant contribution to MID speed perception. © 2000 Published by Elsevier Science Ltd. Keywords: Motion in depth; Speed discrimination; Peripheral vision 1. Introduction motion in depth (MID) could be encoded by the mo- tion system, without the need for disparity sensitive Consider the motion of an object approaching an mechanisms. A unit capable of assessing the difference observer along the median plane. Three major cues to in velocity of each monocular motion signal could be the speed of the object are available.
    [Show full text]
  • Durham E-Theses
    Durham E-Theses Validating Stereoscopic Volume Rendering ROBERTS, DAVID,ANTHONY,THOMAS How to cite: ROBERTS, DAVID,ANTHONY,THOMAS (2016) Validating Stereoscopic Volume Rendering, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/11735/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk Validating Stereoscopic Volume Rendering David Roberts A Thesis presented for the degree of Doctor of Philosophy Innovative Computing Group School of Engineering and Computing Sciences Durham University United Kingdom 2016 Dedicated to My Mom and Dad, my sisters, Sarah and Alison, my niece Chloe, and of course Keeta. Validating Stereoscopic Volume Rendering David Roberts Submitted for the degree of Doctor of Philosophy 2016 Abstract The evaluation of stereoscopic displays for surface-based renderings is well established in terms of accurate depth perception and tasks that require an understanding of the spatial layout of the scene.
    [Show full text]