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motion parallax

Bicheng Luo, Feng Xu, Christian Richardt, Jun-Hai Yong
We propose a novel 360° scene representation for converting real scenes into stereoscopic 3D virtual reality content with head-motion parallax. Our image-based scene representation enables efficient synthesis of novel views with six degrees-of-freedom (6-DoF) by fusing motion fields at two scales: (1) disparity motion fields carry implicit depth information and are robustly estimated from multiple laterally displaced auxiliary viewpoints, and (2) pairwise motion fields enable real-time flow-based blending, which improves the visual fidelity of results by minimizing ghosting and view transition artifacts...
April 2018: IEEE Transactions on Visualization and Computer Graphics
Daria Genzel, Michael Schutte, W Owen Brimijoin, Paul R MacNeilage, Lutz Wiegrebe
Distance is important: From an ecological perspective, knowledge about the distance to either prey or predator is vital. However, the distance of an unknown sound source is particularly difficult to assess, especially in anechoic environments. In vision, changes in perspective resulting from observer motion produce a reliable, consistent, and unambiguous impression of depth known as motion parallax. Here we demonstrate with formal psychophysics that humans can exploit auditory motion parallax, i.e., the change in the dynamic binaural cues elicited by self-motion, to assess the relative depths of two sound sources...
March 12, 2018: Proceedings of the National Academy of Sciences of the United States of America
Lixia Ni, Zhenxing Li, Haifeng Li, Xu Liu
This paper proposes a 360-deg large-scale multiprojection light-field 3D display system, which can reconstruct the light field of models in real space. The reconstructed contents can be observed by multiple viewers from different angles and positions simultaneously. In this system, 360 projectors project images onto a cylindrical light-field diffusion screen whose height is 1.8 m and diameter is 3 m. When moving around the system, viewers can see 3D scenes with smooth-motion parallax, and the frame rate can reach 30 fps and above...
March 10, 2018: Applied Optics
Kyoji Matsushima, Noriaki Sonobe
Digitized holography techniques are used to reconstruct three-dimensional (3D) images of physical objects using large-scale computer-generated holograms (CGHs). The object field is captured at three wavelengths over a wide area at high densities. Synthetic aperture techniques using single sensors are used for image capture in phase-shifting digital holography. The captured object field is incorporated into a virtual 3D scene that includes nonphysical objects, e.g., polygon-meshed CG models. The synthetic object field is optically reconstructed as a large-scale full-color CGH using red-green-blue color filters...
January 1, 2018: Applied Optics
Federico Pedraja, Volker Hofmann, Kathleen M Lucas, Colleen Young, Jacob Engelmann, John E Lewis
A crucial step in forming spatial representations of the environment involves the estimation of relative distance. Active sampling through specific movements is considered essential for optimizing the sensory flow that enables the extraction of distance cues. However, in electric sensing, direct evidence for the generation and exploitation of sensory flow is lacking. Weakly electric fish rely on a self-generated electric field to navigate and capture prey in the dark. This electric sense provides a blurred representation of the environment, making the exquisite sensory abilities of electric fish enigmatic...
January 2, 2018: Proceedings of the National Academy of Sciences of the United States of America
Jacqueline M Fulvio, Bas Rokers
3D motion perception is of central importance to daily life. However, when tested in laboratory settings, sensitivity to 3D motion signals is found to be poor, leading to the view that heuristics and prior assumptions are critical for 3D motion perception. Here we explore an alternative: sensitivity to 3D motion signals is context-dependent and must be learned based on explicit visual feedback in novel environments. The need for action-contingent visual feedback is well-established in the developmental literature...
November 22, 2017: Scientific Reports
Lihua Yang, Yong Gu
Precise heading estimate requires integration of visual optic flow and vestibular inertial motion originating from distinct spatial coordinates (eye- and head-centered, respectively). To explore whether the two heading signals may share a common reference frame along the hierarchy of cortical stages, we explored two multisensory areas in macaques: the smooth pursuit area of the frontal eye field (FEFsem) closer to the motor side, and the dorsal portion of medial superior temporal area (MSTd) closer to the sensory side...
November 14, 2017: ELife
Chiuhsiang Joe Lin, Bereket Haile Woldegiorgis
This work investigated the effects of visual information, parallax, and target positions on movement performances in projection-based stereoscopic displays (PSDs). Fifteen (26.5 ± 3.83 years) self-declared right-handed individuals, with normal or corrected to normal visual acuity, completed pointing tasks in stereoscopic and real environments (RE). Three-dimensional spatial data, recorded by a motion system composed of six infrared cameras, was used to compute kinematics of reaching a real/virtual object at a combination of three parallax and nine frontal planar positions...
November 10, 2017: Human Movement Science
Philipp Flotho, Alejandro Romero-Santiago, Karsten Schwerdtfeger, Matthias Hulser, Lars Haab, Daniel J Strauss
Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of invasive neuroimaging techniques, that possess up to date the highest temporal and spatial resolution on a meso- to macroscopic scale. There are different sources that contribute to the OI signal of which many are noise. In our previous works, we have used dense optical flow for the reduction of movement artefacts...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Kit D Longden, Martina Wicklein, Ben J Hardcastle, Stephen J Huston, Holger G Krapp
Many animals use the visual motion generated by traveling straight-the translatory optic flow-to successfully navigate obstacles: near objects appear larger and to move more quickly than distant objects. Flies are expert at navigating cluttered environments, and while their visual processing of rotatory optic flow is understood in exquisite detail, how they process translatory optic flow remains a mystery. We present novel cell types that have local motion receptive fields matched to translation self-motion, the vertical translation (VT) cells...
November 6, 2017: Current Biology: CB
Tohru Kawakami, Munekazu Date, Mutsumi Sasai, Hideaki Takada
A rotational multiview depth-fused 3D (DFD) display and 360-deg displaying optics using a spatially imaged iris method are proposed to realize a 360-deg 3D image. This method enables displaying clear floating images in a crystal ball. Its symmetric optics provide clear and natural 360-deg images with smooth motion parallax in horizontal and vertical directions using the directional selectivity of a spatially imaged iris method and natural 3D images of a rotational multiview DFD display.
August 1, 2017: Applied Optics
Mehdi Askari, Seong-Bok Kim, Kwang-Soo Shin, Seok-Bum Ko, Sang-Hoo Kim, Dae-Youl Park, Yeon-Gyeong Ju, Jae-Hyeung Park
Occlusion handling in computer-generated holography is of vast importance as it enhances depth information by presenting correct motion parallax of the 3D scene within the viewing angle. In this paper, we propose a computationally efficient occlusion handling technique based on a fully analytic mesh based computer generated holography. The proposed technique uses angular spectrum convolution that renders exact occlusion while preserving all other aspects of the fully analytic mesh based computer generated holography...
October 16, 2017: Optics Express
Alberto Sanna, Mark J Reid, Thomas M Dame, Karl M Menten, Andreas Brunthaler
Little is known about the portion of the Milky Way lying beyond the Galactic center at distances of more than 9 kiloparsec from the Sun. These regions are opaque at optical wavelengths because of absorption by interstellar dust, and distances are very large and hard to measure. We report a direct trigonometric parallax distance of [Formula: see text] kiloparsec obtained with the Very Long Baseline Array to a water maser source in a region of active star formation. These measurements allow us to shed light on Galactic spiral structure by locating the Scutum-Centaurus spiral arm as it passes through the far side of the Milky Way and to validate a kinematic method for determining distances in this region on the basis of transverse motions...
October 13, 2017: Science
F Schaeffel
BACKGROUND: This study examined how humans perform regarding light sensitivity, depth perception and motion vision in comparison to various animals. OBJECTIVE: The parameters that limit the performance of the visual system for these different functions were examined. METHODS: This study was based on literature studies (search in PubMed) and own results. RESULTS: Light sensitivity is limited by the brightness of the retinal image, which in turn is determined by the f‑number of the eye...
November 2017: Der Ophthalmologe: Zeitschrift der Deutschen Ophthalmologischen Gesellschaft
Rui Tang, Longfei Ma, Canhong Xiang, Xuedong Wang, Ang Li, Hongen Liao, Jiahong Dong
RATIONALE: Patients who undergo hilar cholangiocarcinoma (HCAC) resection with concomitant hepatectomy have a high risk of postoperative morbidity and mortality due to surgical trauma to the hepatic and biliary vasculature. PATIENT CONCERNS: A 58-year-old Chinese man with yellowing skin and sclera, abdominal distension, pruritus, and anorexia for approximately 3 weeks. DIAGNOSES: Magnetic resonance cholangiopancreatography and enhanced computed tomography (CT) scanning revealed a mass over the biliary tree at the porta hepatis, which diagnosed to be s a hilar cholangiocarcinoma...
September 2017: Medicine (Baltimore)
Jessica Holmin, Mark Nawrot
To successfully navigate throughout the world, observers must rapidly recover depth information. One depth cue that is especially important for a moving observer is motion parallax. To perceive unambiguous depth from motion parallax, the visual system must integrate information from two different proximal signals, retinal image motion and a pursuit eye movement. Previous research has shown that aging affects both of these necessary components for motion parallax depth perception, but no research has yet investigated how aging affects the mechanism for integrating motion and pursuit information to recover depth from motion parallax...
November 2017: Vision Research
HyungGoo R Kim, Dora E Angelaki, Gregory C DeAngelis
Observer translation produces differential image motion between objects that are located at different distances from the observer's point of fixation [motion parallax (MP)]. However, MP can be ambiguous with respect to depth sign (near vs far), and this ambiguity can be resolved by combining retinal image motion with signals regarding eye movement relative to the scene. We have previously demonstrated that both extra-retinal and visual signals related to smooth eye movements can modulate the responses of neurons in area MT of macaque monkeys, and that these modulations generate neural selectivity for depth sign...
August 23, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
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
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