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motion parallax

Chiuhsiang J Lin, Bereket H Woldegiorgis
In this study, the interaction performances and spatial perceptions in stereoscopic environments were investigated. The experiment compared direct user interactions during pointing at a target, which was continuously visible or presented briefly and disappeared, in both stereoscopic and real environments, at three parallax/depth levels. The position data, collected by a motion system, were used to compute accuracy, signed error, movement time, and throughput. The results showed inaccurate egocentric distance judgment in stereoscopic displays and accurate perceptions in the real world...
October 2017: Applied Ergonomics
Heeseok Oh, Jongyoo Kim, Jinwoo Kim, Taewan Kim, Sanghoon Lee, Alan C Bovik
Conventional stereoscopic 3D (S3D) displays do not provide accommodation depth cues of the 3D image or video contents being viewed. The sense of content depths is thus limited to cues supplied by motion parallax (for 3D video), stereoscopic vergence cues created by presenting left and right views to the respective eyes, and other contextual and perspective depth cues. The absence of accommodation cues can induce two kinds of accommodation vergence mismatches (AVM) at the fixation and peripheral points, which can result in severe visual discomfort...
May 9, 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
Kenichi Nishiyama
An exoscope, high-definition video telescope operating monitor system to perform microsurgery has recently been proposed an alternative to the operating microscope. It enables surgeons to complete the operation assistance by visualizing magnified images on a display. The strong points of exoscope are the wide field of view and deep focus. It minimized the need for repositioning and refocusing during the procedure. On the other hand, limitation of magnifying object was an emphasizing weak point. The procedures are performed under 2D motion images with a visual perception through dynamic cue and stereoscopically viewing corresponding to the motion parallax...
May 2017: Journal of Korean Neurosurgical Society
Athena Buckthought, Ahmad Yoonessi, Curtis L Baker
Motion parallax, the perception of depth resulting from an observer's self-movement, has almost always been studied with random dot textures in simplified orthographic rendering. Here we examine depth from motion parallax in more naturalistic conditions using textures with an overall 1/f spectrum and dynamic perspective rendering. We compared depth perception for orthographic and perspective rendering, using textures composed of two types of elements: random dots and Gabor micropatterns. Relative texture motion (shearing) with square wave corrugation patterns was synchronized to horizontal head movement...
January 1, 2017: Journal of Vision
Ignacio Serrano-Pedraza, Kathleen Vancleef, Jenny C A Read
New forms of stereoscopic 3-D technology offer vision scientists new opportunities for research, but also come with distinct problems. Here we consider autostereo displays where the two eyes' images are spatially interleaved in alternating columns of pixels and no glasses or special optics are required. Column-interleaved displays produce an excellent stereoscopic effect, but subtle changes in the angle of view can increase cross talk or even interchange the left and right eyes' images. This creates several challenges to the presentation of cyclopean stereograms (containing structure which is only detectable by binocular vision)...
November 1, 2016: Journal of Vision
Shinji Nakamura, Stephen Palmisano, Juno Kim
Adding simulated viewpoint jitter or oscillation to displays enhances visually induced illusions of self-motion (vection). The cause of this enhancement is yet to be fully understood. Here, we conducted psychophysical experiments to investigate the effects of different types of simulated oscillation on vertical vection. Observers viewed horizontally oscillating and nonoscillating optic flow fields simulating downward self-motion through an aperture. The aperture was visually simulated to be nearer to the observer and was stationary or oscillating in-phase or counter-phase to the direction of background horizontal oscillations of optic flow...
July 2016: I-Perception
Heng Guo, Shuaicheng Liu, Tong He, Shuyuan Zhu, Bing Zeng, Moncef Gabbouj
In this paper, we extend image stitching to video stitching for videos that are captured for the same scene simultaneously by multiple moving cameras. In practice, videos captured under this circumstance often appear shaky. Directly applying image stitching methods for shaking videos often suffers from strong spatial and temporal artifacts. To solve this problem, we propose a unified framework in which video stitching and stabilization are performed jointly. Specifically, our system takes several overlapping videos as inputs...
September 8, 2016: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
HyungGoo R Kim, Dora E Angelaki, Gregory C DeAngelis
No abstract text is available yet for this article.
October 19, 2016: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
Michael S Langer, Haomin Zheng, Shayan Rezvankhah
Objects such as trees, shrubs, and tall grass consist of thousands of small surfaces that are distributed over a three-dimensional (3D) volume. To perceive the depth of surfaces within 3D clutter, a visual system can use binocular stereo and motion parallax. However, such parallax cues are less reliable in 3D clutter because surfaces tend to be partly occluded. Occlusions provide depth information, but it is unknown whether visual systems use occlusion cues to aid depth perception in 3D clutter, as previous studies have addressed occlusions for simple scene geometries only...
September 1, 2016: Journal of Vision
Cristina de la Malla, Stijn Buiteman, Wilmer Otters, Jeroen B J Smeets, Eli Brenner
It is well known that when we intentionally make large head movements, the resulting motion parallax helps us judge objects' distances. The information about distance could be obtained in various ways: from the changes in the object's position with respect to ourselves, from the changes in its orientation relative to the line of sight, and from the relative retinal motion between the target's image and that of the background. We explore here whether these motion parallax cues are used when we think we are standing still...
July 1, 2016: Journal of Vision
Brian P Keane, Steven M Silverstein, Yushi Wang, Matthew W Roché, Thomas V Papathomas
Schizophrenia patients with more positive symptoms are less susceptible to depth inversion illusions (DIIs) in which concave objects appear as convex. It remains unclear, however, the extent to which this perceptual advantage uniquely characterizes the schizophrenia phenotype. To address the foregoing, we compared 30 bipolar disorder patients to a previously published sample of healthy controls (N=25) and schizophrenia patients (N=30). The task in all cases was to judge the apparent convexity of physically concave faces and scenes...
October 2016: Schizophrenia Research
Brian Rogers
In the kinetic depth effect, the direction of the perceived depth and the direction of apparent rotation of a 3-D structure are linked, and typically ambiguous, whereas depth from motion parallax during both observer- and object-movement is stable and unambiguous. Rogers and Rogers demonstrated that the vertical perspective transformations play an important role in disambiguating the direction of the perceived depth in parallax-defined surfaces but more recently Nawrot et al. have proposed that pursuit eye movements provide the crucial disambiguating information...
June 24, 2016: Perception
Brian Rogers
There are many similarities between binocular disparity and motion parallax as sources of information about the structure and layout of 3-D objects and surfaces. The former can be thought of as a transformation that maps one eye's image onto the other while the latter is a transformation that maps the changes in one eye's image over time. There are many empirical similarities in the ways we use the two sources of information but there are also significant differences. A consideration of those differences leads to the conclusion that, rather than seeing motion parallax as a close analogue of binocular stereopsis, motion parallax is better thought of as a special case of the kinetic depth effect in which the depth order of the depicted 3-D object or surface can be disambiguated by vertical perspective information...
June 24, 2016: Perception
HyunGoo R Kim, Dora E Angelaki, Gregory C DeAngelis
In addition to depth cues afforded by binocular vision, the brain processes relative motion signals to perceive depth. When an observer translates relative to their visual environment, the relative motion of objects at different distances (motion parallax) provides a powerful cue to three-dimensional scene structure. Although perception of depth based on motion parallax has been studied extensively in humans, relatively little is known regarding the neural basis of this visual capability. We review recent advances in elucidating the neural mechanisms for representing depth-sign (near versus far) from motion parallax...
June 19, 2016: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
Tilman Triphan, Aljoscha Nern, Sonia F Roberts, Wyatt Korff, Daniel Q Naiman, Roland Strauss
Climbing over chasms larger than step size is vital to fruit flies, since foraging and mating are achieved while walking. Flies avoid futile climbing attempts by processing parallax-motion vision to estimate gap width. To identify neuronal substrates of climbing control, we screened a large collection of fly lines with temporarily inactivated neuronal populations in a novel high-throughput assay described here. The observed climbing phenotypes were classified; lines in each group are reported. Selected lines were further analysed by high-resolution video cinematography...
2016: Scientific Reports
Jessica Holmin, Mark Nawrot
Successful navigation in the world requires effective visuospatial processing. Unfortunately, older adults have many visuospatial deficits, which can have severe real-world consequences. Although some of these age effects are well documented, some others, such as the perception of depth from motion parallax, are poorly understood. Depth perception from motion parallax requires intact retinal image motion and pursuit eye movement processing. Decades of research have shown that both motion processing and pursuit eye movements are affected by age; it follows that older adults may also be less sensitive to depth from motion parallax...
August 2016: Attention, Perception & Psychophysics
Zhi Gao, Pengfei Wang, Ruifang Zhai, Yazhe Tang
Both frontally placed eyes and laterally placed eyes are popular in nature, and although which one is better could be one of the most intuitive questions to ask, it could also be the hardest question to answer. Their most obvious difference is that, at least as supposed in the computer vision community, stereopsis plays the central role in the visual system composed of frontally placed eyes (or cameras); however, it is not available in the lateral configuration due to the lack of overlap between the visual fields...
April 1, 2016: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Michael Ratzlaff, Mark Nawrot
The visual system uses an extraretinal pursuit eye movement signal to disambiguate the perception of depth from motion parallax. Visual motion in the same direction as the pursuit is perceived nearer in depth while visual motion in the opposite direction as pursuit is perceived farther in depth. This explanation of depth sign applies to either an allocentric frame of reference centered on the fixation point or an egocentric frame of reference centered on the observer. A related problem is that of depth order when two stimuli have a common direction of motion...
September 2016: Perception
Hao Zhang, Yan Zhao, Liangcai Cao, Guofan Jin
We propose an efficient algorithm using layered holographic stereogram for three-dimensional (3D) computer-generated holograms. The hologram is spatially partitioned into multiple holographic elements (hogels) to provide the occlusion effect and motion parallax by use of multiple viewpoint rendering. Each hogel is calculated with inverse Fresnel diffraction by slicing the viewing frustum according to the depth image. The sliced layers can provide accurate depth cues for reconstruction since the geometric information of the 3D scene is faithfully matched...
January 20, 2016: Applied Optics
Gengkun Wang, Wei Xiang, Mark Pickering
Current telehealth services are dominated by conventional 2D video conferencing systems, which are limited in their capabilities in providing a satisfactory communication experience due to the lack of realism. The "immersiveness" provided by 3D technologies has the potential to promote telehealth services to a wider range of applications. However, conventional stereoscopic 3D technologies are deficient in many aspects, including low resolution and the requirement for complicated multi-camera setup and calibration, and special glasses...
March 2016: Computer Methods and Programs in Biomedicine
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