Quantitative Measurement of Human Visual Characteristic on Depth Perception with Using Random-Dot Stimulus

2000 ◽  
Vol 44 (21) ◽  
pp. 3-500-3-500
Author(s):  
Jing-Long Wu ◽  
Kazuyoshi Tsukamoto
Keyword(s):  
Depth Perception ◽  
Quantitative Measurement ◽  
Binocular Disparity ◽  
Experimental Results ◽  
Depth Information ◽  
Head Mounted Display ◽  
Visual Characteristic

Human interactive characteristic between the binocular disparity and the occlusion for depth perception is measured with using random-dot stimulus. The experimental results suggested that if the binocular disparity is set at a proper value, the depth information is mainly obtained from the cue of the binocular disparity, and if the occlusion ratio is larger than some constant value the depth information is obtained from the cue of the occlusion. Based on the experimental results, we can find a method to make images with depth information in the Head Mounted Display (HMD) when the cues of the binocular disparity and the occlusion are concurrently used.

scholarly journals Near-optimal combination of disparity across a log-polar scaled visual field

2019 ◽  
Author(s):  
Guido Maiello ◽  
Manuela Chessa ◽  
Peter J. Bex ◽  
Fabio Solari
Keyword(s):  
Visual Cortex ◽  
Visual Field ◽  
Visual System ◽  
Primary Visual Cortex ◽  
Depth Perception ◽  
Binocular Disparity ◽  
Spatial Scales ◽  
Visual Input ◽  
Depth Information ◽  
Central Vision

AbstractThe human visual system is foveated: we can see fine spatial details in central vision, whereas resolution is poor in our peripheral visual field, and this loss of resolution follows an approximately logarithmic decrease. Additionally, our brain organizes visual input in polar coordinates. Therefore, the image projection occurring between retina and primary visual cortex can be mathematically described by the log-polar transform. Here, we test and model how this space-variant visual processing affects how we process binocular disparity, a key component of human depth perception. We observe that the fovea preferentially processes disparities at fine spatial scales, whereas the visual periphery is tuned for coarse spatial scales, in line with the naturally occurring distributions of depths and disparities in the real-world. We further show that the visual field integrates disparity information across the visual field, in a near-optimal fashion. We develop a foveated, log-polar model that mimics the processing of depth information in primary visual cortex and that can process disparity directly in the cortical domain representation. This model takes real images as input and recreates the observed topography of disparity sensitivity in man. Our findings support the notion that our foveated, binocular visual system has been moulded by the statistics of our visual environment.Author summaryWe investigate how humans perceive depth from binocular disparity at different spatial scales and across different regions of the visual field. We show that small changes in disparity-defined depth are detected best in central vision, whereas peripheral vision best captures the coarser structure of the environment. We also demonstrate that depth information extracted from different regions of the visual field is combined into a unified depth percept. We then construct an image-computable model of disparity processing that takes into account how our brain organizes the visual input at our retinae. The model operates directly in cortical image space, and neatly accounts for human depth perception across the visual field.

Quantitative measurement of vertigo frequency: Preliminary results

2003 ◽  
Vol 13 (1) ◽  
pp. 53-56
Author(s):  
Robert Aureo Zalewski-Zaragoza ◽  
Erik Scott Viirre
Keyword(s):  
Quantitative Measurement ◽  
Average Frequency ◽  
Repeated Measurements ◽  
Virtual Image ◽  
Subjective Ratings ◽  
Image System ◽  
Head Mounted Display ◽  
Tinnitus Treatment ◽  
Specific Frequency ◽  
Rehabilitation Exercises

Persons who experience vertigo often describe their symptoms as a sensation of oscillations. Based on such a description, a pilot study was performed to determine if the frequency of the vertigo sensation could be quantified in a manner analogous to tone matching in tinnitus treatment. Fifteen subjects were tested using a virtual image system that consisted of a head mounted display showing a scene that oscillated horizontally or vertically at an adjustable frequency. Subjects were asked to adjust the direction and frequency to match their typical vertigo sensation. Results show that most persons with chronic vertigo had symptoms that could be realistically simulated by vection induced by the oscillating scene and that matched to a consistent specific frequency. They reported an average frequency of 1.09 Hz (range 0.27 to 3.3 Hz, SD 0.25). The large majority (13 out of 15) matched to a horizontal stimulus. Subjects that gave particularly high subjective ratings of the similarity of the motion sensation (7–8 out of 10) from the vection to their vertigo had lower frequency matches (average 0.61 +/- 0.25). Repeated measurements in 4 subjects 8 to 27 days later showed consistent results. This vertigo measurement technique may be used in the future to assess the ability of vestibular rehabilitation to reduce chronic vertigo. Identification of a specific frequency of chronic vertigo may be important in the specification of rehabilitation exercises.

scholarly journals Viewpoint Usability for Desktop Augmented Reality

2006 ◽  
Vol 5 (3) ◽  
pp. 33-39 ◽  
Author(s):  
Seokhee Jeon ◽  
Hyeongseop Shim ◽  
Gerard J. Kim
Keyword(s):  
Augmented Reality ◽  
Task Performance ◽  
Depth Perception ◽  
Object Manipulation ◽  
Head Mounted Display ◽  
Usability Problems ◽  
Head Mounted Displays ◽  
Hand Eye Coordination ◽  
Manipulation Task ◽  
Perceived Usability

In this paper, we have investigated the comparative usability among three different viewing configurations of augmented reality (AR) system that uses a desktop monitor instead of a head mounted display. In many cases, due to operational or cost reasons, the use of head mounted displays may not be viable. Such a configuration is bound to cause usability problems because of the mismatch in the user's proprioception, scale, hand eye coordination, and the reduced 3D depth perception. We asked a pool of subjects to carry out an object manipulation task in three different desktop AR set ups. We measured the subject's task performance and surveyed for the perceived usability and preference. Our results indicated that placing a fixed camera in the back of the user was the best option for convenience and attaching a camera on the user�s head for task performance. The results should provide a valuable guide for designing desktop augmented reality systems without head mounted displays

Virtual Visual and Auditory Display Aids for a Peg Insertion Task

1997 ◽  
Vol 41 (2) ◽  
pp. 1263-1267
Author(s):  
Kenneth Nemire
Keyword(s):  
Movement Time ◽  
Depth Information ◽  
Auditory Display ◽  
Discrete Movements ◽  
Stereoscopic Displays ◽  
Head Mounted Display ◽  
Immersive Virtual Environment ◽  
Stereo Display ◽  
Place Task ◽  
Task Conditions

Effects of visual and auditory display enhancements to a pick-and-place task performed in an immersive virtual environment were evaluated to determine whether the enhancements may replace depth information provided by stereoscopic visual displays. Participants used a commercial head-mounted display, spatial trackers on the head and hand, and a control wand. Independent variables included biocular or stereo viewing, movement amplitude, target diameter, and audio or visual enhancements. Dependent variables were movement time and number of discrete movements required to complete the task. Results indicated the stereo display and the display enhancements provided no performance advantages over the biocular display for the easier task conditions. Further, visual and auditory enhancements to the biocular display were found that resulted in performance that was not different from using stereoscopic displays. Implications of the results are discussed.

Interaction between Colour and Depth Channels in Transparent Colour Perception

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 115-115
Author(s):  
K Okajima ◽  
M Takase ◽  
S Takahashi
Keyword(s):  
Information Processing ◽  
Visual System ◽  
Binocular Disparity ◽  
Depth Information ◽  
Apparent Depth ◽  
Colour Perception

Two colours can be perceived at one location on overlapping planes only when the front plane is transparent. This phenomenon suggests that colour information processing is not independent of depth information processing and vice versa. To investigate the interaction between colour and depth channels, we used colour stimuli and binocular parallax to identify the conditions for transparency. Each stimulus, presented on a CRT to one eye, consisted of a centre patch and a surround. Binocular disparity was set so that the centre patch could be seen behind the surround. However, the surround appears to be behind the centre patch when the surround is perceived as an opaque plane. We examined several combinations of basic colours for the centre patch and surround. The surround luminance was constant at 1.0 cd m−2 and the luminance of the centre was varied. Subjects used the apparent depth of the surround to report whether or not transparency occurred. The results show two types of transparency: ‘bright-centre transparency’ and ‘dark-centre transparency’. We found that the range of centre luminances which yield transparency depends on the combination of centre and surround colours, ie influences of brightness and colour opponency were found. We conclude that there is interaction between colour and depth channels in the visual system.

Depth from shading and disparity in humans and monkeys

2007 ◽  
Vol 24 (2) ◽  
pp. 207-215 ◽  
Author(s):  
YING ZHANG ◽  
VERONICA S. WEINER ◽  
WARREN M. SLOCUM ◽  
PETER H. SCHILLER
Keyword(s):  
Animal Model ◽  
Visual System ◽  
Depth Perception ◽  
Discrimination Task ◽  
Stimulus Display ◽  
Neural Mechanisms ◽  
Depth Information ◽  
Depth Cues ◽  
Good Animal Model

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.

Does Binocular Disparity or Familiar Size Information Override Effects of Relative Size on Judgements of Time to Contact?

2005 ◽  
Vol 58 (5) ◽  
pp. 865-886 ◽  
Author(s):  
Patricia R. DeLucia
Keyword(s):  
Binocular Disparity ◽  
Relative Size ◽  
Depth Information ◽  
Sources Of Information ◽  
Familiar Size ◽  
Multiple Sources ◽  
Time To Contact ◽  
Size Information ◽  
Source Of Information ◽  
Do So

Previous studies indicate that non-tau sources of depth information, such as pictorial depth cues, can influence judgements of time to contact (TTC). The effect of relative size on such judgements, the size-arrival effect, is particularly robust. However, earlier studies of the size-arrival effect did not include binocular disparity or familiar size information. The effects of these cues on relative TTC judgements were measured. Results suggested that disparity can eliminate the size-arrival effect but that the amount of disparity needed to do so is greater than typical stereoacuity thresholds. In contrast, familiar size eliminated the size-arrival effect even when disparity information was not available. Furthermore, disparity contributed more to performance when familiar size was present than when it was absent. Consistent with previous studies, TTC judgements were influenced by multiple sources of information. The present results suggested further that familiar size is one such source of information and that familiar size moderates the influence of binocular disparity information.

scholarly journals An ECG Denoising Method Based on the Generative Adversarial Residual Network

2021 ◽  
Vol 2021 ◽  
pp. 1-23
Author(s):  
Bingxin Xu ◽  
Ruixia Liu ◽  
Minglei Shu ◽  
Xiaoyi Shang ◽  
Yinglong Wang
Keyword(s):  
Noise Reduction ◽  
Reduction Process ◽  
Experimental Results ◽  
Depth Information ◽  
Ecg Signal ◽  
Massachusetts Institute Of Technology ◽  
Residual Network ◽  
Denoising Autoencoder ◽  
Generative Adversarial Network ◽  
Ecg Denoising

High-quality and high-fidelity removal of noise in the Electrocardiogram (ECG) signal is of great significance to the auxiliary diagnosis of ECG diseases. In view of the single function of traditional denoising methods and the insufficient performance of signal details after denoising, a new method of ECG denoising based on the combination of the Generative Adversarial Network (GAN) and Residual Network is proposed. The method adopted in this paper is based on the GAN structure, and it restructures the generator and discriminator. In the generator network, residual blocks and Skip-Connecting are used to deepen the network structure and better capture the in-depth information in the ECG signal. In the discriminator network, the ResNet framework is used. In order to optimize the noise reduction process and solve the lack of local relevance considering the global ECG problem, the differential function and overall function of the maximum local difference are added in the loss function in this paper. The experimental results prove that the method used in this article has better performance than the current excellent S-Transform (S-T) algorithm, Wavelet Transform (WT) algorithm, Stacked Denoising Autoencoder (S-DAE) algorithm, and Improved Denoising Autoencoder (I-DAE) algorithm. Experiments show that the Root Mean Square Error (RMSE) of this method in the Massachusetts Institute of Technology and Beth Israel Hospital (MIT-BIH) noise pressure database is 0.0102, and the Signal-to-Noise Ratio (SNR) is 40.8526 dB, which is compared with that of the most advanced experimental methods. Our method improves the SNR by 88.57% on average. Besides the three noise intensities for comparison experiments, additional noise reduction experiments are also performed under four noise intensities in our paper. The experimental results verify the scientific nature of the model, which is that our method can effectively retain the important information conveyed by the original signal.

scholarly journals TeleParallax: Low-Motion-Blur Stereoscopic System With Correct Interpupillary Distance for 3D Head Rotations

2021 ◽  
Vol 2 ◽  
Author(s):  
Tomohiro Amemiya ◽  
Kazuma Aoyama ◽  
Michitaka Hirose
Keyword(s):  
Depth Perception ◽  
Three Dimensional ◽  
Head Tilt ◽  
Motion Blur ◽  
Depth Information ◽  
Camera Motion ◽  
Robotic Arms ◽  
Interpupillary Distance ◽  
Omnidirectional Image ◽  
Head Rotations

Binocular parallax provides cues for depth information when a scene is viewed with both eyes. In visual telepresence systems, stereo cameras are commonly used to simulate human eyes. However, motion blur occurs when these cameras are rotated quickly. The use of omnidirectional cameras can reduce the motion blur, but does not provide the correct interpupillary distance (IPD) when viewers tilt or turn their heads sideways. We propose a method called TeleParallax, in which two omnidirectional cameras are separated by the IPD and the direction of the lenses are kept constant in world coordinates by robotic arms during three-dimensional head rotations. TeleParallax can suppress the increase in image buffering during head rotations because each camera can capture an omnidirectional image with the lens direction fixed. We conducted three user studies to evaluate the perceptual effect of head tilt, eye asynchrony, and delays in IPD correction for a particular rotation. The results indicate that TeleParallax can provide depth perception that is independent of the head movement with less visual discomfort. Although the results show that the users were sensitive to the asynchrony between their eyes and to camera motion during IPDs, they retained the feeling of depth perception within interocular delays of 70 ms and motion velocity of 75°/s. These results imply that TeleParallax has remarkable potential for visual telepresence systems.

Sign in / Sign up

Export Citation Format

Share Document