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Objectives: Computer usage has rapidly grown. This is because it helps to resolve problems, i.e., encountered in daily life by individuals. Various monitor screens that have been developed affect the user’s eyes. Screen size is one of the relevant impacts. Thus, this study compared the immediate effects of two computer screen sizes on visual fatigue in Video Display Terminal (VDT) users. Methods: Twenty female VDT users participated in this study. Using a randomized block design for the study, the study participants randomly drew a ballot to determine the order of using an 18.5-inch and 23-inch computer screen size. The research participants were assessed by a visual fatigue score, critical flicker frequency, and dry eye score before and after using both computer screen sizes. They were tested in an ergonomic computer workstation for 2 hours. Besides, where they rested between each workstation for ≥30 minutes or until presetting no eye fatigue symptoms. The relevant data were compared between before and after using the computers and between the two different screen sizes. Results: The collected results suggested no significant difference in the visual fatigue score, critical flicker frequency, and dry eye score between using either computer screen sizes (P>0.05). However, there were significant differences in the visual fatigue score, critical flicker frequency, and dry eye score between before and after computer screen usage (P

The screen size and the resolution of the displays available to the consumer market have been steadily increasing. According to established vision science, there are limits to the human visual system for the perceptibility of resolution at typical viewing distances. This paper discusses a subjective evaluation that was performed to assess the perceptual difference between UHD-1/4K and UHD-2/8K for various types of content on an UHD-2/8K consumer display. It also performs a detailed frequency and visibility analysis of the content to determine the characteristics of the most perceptual content and establishes a relationship between the subjective test results and the vision science .

While online experiments have shown tremendous potential to study larger and more diverse participant samples than is possible in the lab, the uncontrolled online environment has prohibited many types of psychophysical studies due to difficulties controlling the viewing distance and stimulus size. We introduce the Virtual Chinrest, a method that measures a participant’s viewing distance in the web browser by detecting a participant’s blind spot location. This makes it possible to automatically adjust stimulus configurations based on an individual’s viewing distance. We validated the Virtual Chinrest in two laboratory studies in which we varied the viewing distance and display size, showing that our method estimates participants’ viewing distance with an average error of 3.25 cm. We additionally show that by using the Virtual Chinrest we can reliably replicate measures of visual crowding, which depends on a precise calculation of visual angle, in an uncontrolled online environment. An online experiment with 1153 participants further replicated the findings of prior laboratory work, demonstrating how visual crowding increases with eccentricity and extending this finding by showing that young children, older adults and people with dyslexia all exhibit increased visual crowding, compared to adults without dyslexia. Our method provides a promising pathway to web-based psychophysical research requiring controlled stimulus geometry.

Touch screen interactions have been linked to repetitive strain injuries. Their use as an input channel to user interfaces can also have limitations due to screen size or mobility constraints. In this work, we investigate the feasibility of a neck-mounted wearable interface for software interaction, using only subtle head movements. Technologies and configurations for sensoring the neck region, including e-textiles and flex sensors, are considered. The type and placement of the sensors are evaluated. An end-to-end prototype system is developed, which takes the sensor readings from the bespoke neck hardware and wirelessly transmits them to a smart phone, for carrying-out the motion classification and interfacing with applications. The classification accuracy of common head movements using classical machine learning algorithms are evaluated. A classification accuracy of 91% is achieved with data collected from the prototype, for a library of five common head gestures and positions.

Display of images on different display devices having varied size and aspect ratio requires one to resize them. Many attempts have been made to perform content-aware image retargeting while generating an image compatible with a target display size. Seam carving is one of the image retargeting operators which alters the size of an image by removing least energy pixels. However, it requires high computational time in order to perform retargeting. In this study, the authors accelerate the naive seam carving process by removal or insertion of multiple pixel wide batch seam in a single iteration rather than a single pixel wide seam. Along with the energy of pixels to be removed, inserted energy after the removal of a batch seam is also minimised in order to prevent the inclusion of false edges. The width of a batch seam is a critical factor which is made adaptive during the retargeting process to preserve the energy of an image. They have shown a significant decrease in computational time with the increase in the width of a batch seam. They have compared the proposed technique with other state-of-the-art image retargeting operators using different quality assessment metrics and visual results.

In our day life, the televisions are viewed under the various conditions of each households, and we rarely watch TV from a standard distance with the gaze position used in image quality evaluation. Accordingly, we examined mean gaze point distribution affected by observation conditions (the resolution, screen size, viewing position). Consequently, we found that there were mostly no differences in mean gaze point position and its standard deviation under the different conditions. It was suggested that consumers could choose and buy a display of their preferred resolution and size, and arrange a display with fitting each the room layout.

Several lines of evidence point to the existence of a visual processing advantage for horizontal over vertical orientations. We investigated whether such a horizontal advantage exists in the context of top-down visual search. Inspired by change detection studies, we created displays where a dynamic target -- a horizontal or a vertical group of five dots that changed contrast synchronously -- was embedded within a randomly flickering grid of dots. The display size (total dots) varied across trials, and the orientation of the target was constant within interleaved blocks. As expected, search was slow and inefficient. Importantly, participants were almost a second faster finding horizontal compared to vertical targets. They were also more efficient and more accurate during horizontal search. Such findings establish that the attentional templates thought to guide search for known targets can exhibit strong orientation anisotropies. We discuss possible underlying mechanisms and how these might be explored in future studies.

Smartwatches can be used independently from smartphones, but input tasks like messaging are cumbersome due to the small display size. Parts of the display are hidden during interaction, which can lead to incorrect input. For simplicity, instead of general text input a small set of answer options are often provided, but these are limited and impersonal. In contrast, free-form drawings can answer messages in a very personal way, but are difficult to produce on small displays. To enable precise drawing input on smartwatches we present a magnetic stylus that is tracked on the back of the hand. In an evaluation of several algorithms we show that 3D position estimation with a 7.5x20mm magnet reaches a worst-case 6% relative position error on the back of the hand. Furthermore, the results of a user study are presented, which show that in the case of drawing applications the presented technique is faster and more precise than direct finger input.

In the digital age, the use of technology in music has become a trend with computers and tablet devices, smartphones and the like. In this study, headphone products as the research object, the most suitable headphone color, pattern and experimental display size. First of all, this study uses 16 psychological test methods to investigate and compare the color reaction products of color technology and color psychology of commercial technology products, and carries out the analysis of semantic differences, making statistical research in black and white to obtain the best color matching color. Finally, use the Likert scale statistics and analysis. The results show that black headphones, minimalist design to get most of the preferences

We present a study into the perception of display brightness as related to the physical size and distance of the screen from the observer. Brightness perception is a complex topic, which is influenced by a number of lower- and higher-order factors—with empirical evidence from the cinema industry suggesting that display size may play a significant role. To test this hypothesis, we conducted a series of user studies exploring brightness perception for a range of displays and distances from the observer that span representative use scenarios. Our results suggest that retinal size is not sufficient to explain the range of discovered brightness variations, but is sufficient in combination with physical distance from the observer. The resulting model can be used as a step toward perceptually correcting image brightness perception based on target display parameters. This can be leveraged for energy management and the preservation of artistic intent. A pilot study suggests that adaptation luminance is an additional factor for the magnitude of the effect.

Purpose A larger display at the same viewing distance provides relative-size magnification for individuals with central vision loss (CVL). However, the resulting large visible area of the display is expected to result in more head rotation, which may cause discomfort. We created a zoom magnification technique that placed the center of interest (COI) in the center of the display to reduce the need for head rotation. Methods In a 2 × 2 within-subject study design, 23 participants with CVL viewed video clips from 1.5 m (4.9 feet) shown with or without zoom magnification, and with a large (208 cm/82” diagonal, 69°) or a typical (84 cm/33”, 31°) screen. Head position was tracked and a custom questionnaire was used to measure discomfort. Results Video comprehension was better with the large screen (P < 0.001) and slightly worse with zoom magnification (P = 0.03). Oddly, head movements did not vary with screen size (P = 0.63), yet were greater with zoom magnification (P = 0.001). This finding was unexpected, because the COI remains in the center with zoom magnification, but moves widely with a large screen and no magnification. Conclusions This initial attempt to implement the zoom magnification method had flaws that may have decreased its effectiveness. In the future, we propose alternative implementations for zoom magnification, such as variable magnification. Translational Relevance We present the first explicit demonstration that relative-size magnification improves the video comprehension of people with CVL when viewing video.

Light field 3D displays are expected to play an important role as terminal devices, visualizing 3D objects apparently floating in the air, or letting viewers see through a window with a scene behind it. Currently, there are neither methods nor practical tools to quantify light field display's effective resolution or the perceived quality of the presented imagery. Most 3D displays are simply characterized by the total number of pixels or light rays; however this number does not properly characterize the distribution of the emitted light rays, nor the level of detail that the display can visualize properly. This paper presents methods to measure the spatial (i.e. 2D equivalent) and angular (i.e. directional) resolution of a given light-field display. The frequency domain analysis of recorded test patterns gives the spatial resolution limit of the display under test, while angular resolution is determined by the display's ability to pass through patterns of uniform, angle dependant patterns. It also presents a subjective experiment to corroborate the objectively measured spatial resolution. acceptedVersion

The viewing-zone scanning holographic display, which can enlarge both screen size and viewing zone, is modified to enable color image generation by using the time-multiplexing technique; R, G, and B lasers sequentially illuminate a single microelectromechanical systems spatial light modulator with a high frame rate. The viewing-zone scanning system enlarges screen size by using a magnifying imaging system and generates a large number of reduced viewing zones that are aligned in the horizontal direction by a horizontal scanner to enlarge the viewing zone. The interval of the reduced viewing zones is set to be one-third of the width of the reduced viewing zones or less so that three sets of reduced viewing zones are generated corresponding to the three colors. Color image generation was demonstrated for a screen size of 2.0 in. and a viewing zone angle of 40.0°.

The ability of images to evoke emotions in people has been well documented in previous research, as well as the differences in the emotional perception of images when viewed on different-sized screens and device types. The ability of thermal stimuli to evoke emotions in people when used for media augmentation has also been examined. However, little is known about how thermal stimuli can be used to enhance or reduce affect in images with varying emotional properties displayed in different sizes or on different devices. To the best of our knowledge, no work has been conducted to investigate whether there is any difference in the effect thermal augmentation has on images displayed in different sizes on different device types. This paper presents two user studies to address this research gap. Study 1 explored the effect thermal stimulation has on images displayed in different sizes. Images were displayed in sizes corresponding to the full screen display of a laptop, tablet and mobile phone. In study 2, we examined whether the actual presentation device (tablet and mobile) plays a role in the emotional perception of images displayed on mobile devices. Results showed that thermal augmentation was most effective in modulating emotions in small-sized pictures (427 × 240 pixels display size) and pictures displayed on a mobile phone. Thermal stimuli also reduced emotions in medium display sizes (corresponding to the full screen display of a tablet).

With the recent evolution of ultra-high-definition (UHD) display technology, viewers can enjoy high-resolution content more realistically over TVs, virtual reality, portable, and wearable devices. To increase the visual attraction viewers perceive, post-processing of video content has been more powerfully conducted in such commercial devices. In this paper, we define a new terminology visual preference to quantify viewer perceptual preferences in a certain viewing environment with UHD images processed using sharpness and contrast enhancements. Viewers’ visual preference for UHD images depends on the spatial resolution afforded by the UHD display, which in turn depends on the viewing geometry of the display resolution, display size, and viewing distance. In addition, viewers can perceive different degrees of quality and sharpness according to the content enhancement type and level, which leads to variation in the statistical dynamics of spatial image information. In this paper, we explore a novel methodology called the visual preference assessment model (VPAM) that accounts for content enhancement features, diverse viewing geometry, and statistical dynamics variation. The VPAM is a no-reference assessment method designed using an elaborate subjective preference assessment with support vector regression as the machine learning algorithm. The VPAM far outperforms previous methods in terms of correlation, 0.45–0.56, with the visual preference assessment.

In our previous study, we measured head movement and eye movements by changing viewing position and distance. Our results showed that mean gaze point position depends on video contents, viewing position and viewing distance. However, to the best of our knowledge, no research has yet been done on the line of sight in the case of showing a video of different resolutions and sizes at the same viewing distance. This is different from the general conditions in image quality evaluation, but we often watch videos under this condition in daily life. Therefore, we measured mean gaze point position when screen resolution and size are changed, finding that, if resolution was changed, only different viewing positions affected the position of the mean gaze point. Except in this case, there was no change in mean gaze point position and its standard deviation due to resolution or screen size.

While bringing portability and convenience to their users, the small screen size of mobile devices raises the concern that it might impact a user’s acquisition of spatial knowledge. Visualizing information of off-screen objects on mobile device has thus been introduced as a possible way to overcome this problem. Some approaches encode the distance to off-screen objects very well, but they have not considered the identities of objects, which could serve as easily-recognizable landmarks of recognition. Other approaches have addressed the visualization of distant objects’ identities as landmarks, but they have not considered the representation of distance to their actual locations. Following these approaches, this study introduces the use of visual variable size in the design of symbols for off-screen landmarks to translate both information about both direction and distance. To further investigate the efficiency of using these graduated size symbols, we apply ratio and ordinal levels of measurement to assign size to the symbols. Results show, size at the ordinal level leads to higher efficiency in understanding distance to off-screen locations. Both designs, however, yield challenges in participants’ understanding of distance based on the symbol’s size. As the initial step of investigating the use of visual variables in the design of symbols for off-screen landmarks, we suggest more visual variables be considered in follow-up designs to provide a more comprehensive understanding regarding the effectiveness of visualizing off-screen landmarks on mobile devices.

With the advent of global positioning system technology, smart phones are used as portable navigation systems. Guidelines that ensure driving safety while using conventional on-board navigation systems have already been published but do not extend to portable navigation systems; therefore, this study focused on the analysis of the eye-gaze tracking of drivers interacting with portable navigation systems in an urban area. Combinations of different display sizes and positions of portable navigation systems were adopted by 20 participants in a driving simulator experiment. An expectation maximum algorithm was proposed to classify the measured eye-gaze points; furthermore, three measures of glance frequency, glance time, and total glance time as a percentage were calculated. The results indicated that the convenient display position with a small visual angle can provide a significantly shorter glance time but a significantly higher glance frequency; however, the small-size display will bring on significantly longer glance time that may result in the increasing of visual distraction for drivers. The small-size portable display received significantly lower scores for subjective evaluation of acceptability and fatigue; moreover, the small-size portable display on the conventional built-in position received significantly lower subjective evaluation scores than that of the big-size one on the upper side of the dashboard. In addition, it indicated an increased risk of rear-end collision that the proportion of time that the time-to-collision was less than 1 s was significantly shorter for the portable navigation than that of traditional on-board one.

We present DisCo, a novel display-camera communication system. DisCo enables displays and cameras to communicate with each other while also displaying and capturing images for human consumption. Messages are transmitted by temporally modulating the display brightness at high frequencies so that they are imperceptible to humans. Messages are received by a rolling shutter camera that converts the temporally modulated incident light into a spatial flicker pattern. In the captured image, the flicker pattern is superimposed on the pattern shown on the display. The flicker and the display pattern are separated by capturing two images with different exposures. The proposed system performs robustly in challenging real-world situations such as occlusion, variable display size, defocus blur, perspective distortion, and camera rotation. Unlike several existing visible light communication methods, DisCo works with off-the-shelf image sensors. It is compatible with a variety of sources (including displays, single LEDs), as well as reflective surfaces illuminated with light sources. We have built hardware prototypes that demonstrate DisCo’s performance in several scenarios. Because of its robustness, speed, ease of use, and generality, DisCo can be widely deployed in several applications, such as advertising, pairing of displays with cell phones, tagging objects in stores and museums, and indoor navigation.

Wearable motion capture systems using Micro-Electro-Mechanical-Systems (MEMS) based Inertial Measurement Units (IMUs) are considered a promising low-cost technology that evolves rapidly over the last few years. A wearable pointing system that consists of a pair of IMUs with acceleration and angular velocity sensors is presented in this work. Each IMU is equipped with Bluetooth connectivity and both are mounted on the user’s arm. The system provides automatic pointing on the presentation screen by capturing the arm’s rotational movement and by exploiting the speaker’s relative to the screen position. In this paper, we present the system’s design and its evaluation along with a training method for estimating the user-screen distance and relative position. Experimental results show promising pointing accuracy and precision in a variety of different display sizes and distances making the system an effective solution for automatic on-screen pointing.

Current three-dimensional displays cannot fully reproduce all depth cues used by a human observer in the real world. Instead, they create only an illusion of looking at a three-dimensional scene. This leads to a number of challenges during the content creation process. To assure correct depth reproduction and visual comfort, either the acquisition setup has to be carefully controlled or additional postprocessing techniques have to be applied. Furthermore, these manipulations need to account for a particular setup that is used to present the content, for example, viewing distance or screen size. This creates additional challenges in the context of personal use when stereoscopic content is shown on TV sets, desktop monitors, or mobile devices. We address this problem by presenting a new system for streaming stereoscopic content. Its key feature is a computationally efficient depth adjustment technique which can automatically optimize viewing experience for videos of field sports such as soccer, football, and tennis. Additionally, the method enables depth personalization to allow users to adjust the amount of depth according to their preferences. Our stereoscopic video streaming system was implemented, deployed, and tested with real users.

We studied the stereoscopic effect obtained from a two-dimensional image without using binocular parallax, which we call “natural3D” (n3D). Unlike a parallax-based three-dimensional (3D) display system, n3D causes less tiredness and is free from a decrease of the resolution by half because of image division and viewing position dependence. To make the display with these effects comfortable to use, we conducted statistical tests with sensory evaluation experiments and a quantitative evaluation based on physiological responses. These examinations revealed that the n3D effect can be effectively obtained by using, for example, the characteristics of an organic light-emitting diode display, such as high contrast and easy bendability. This study discusses optimal display curvatures for displays of different sizes that enhance n3D and reduce tiredness, which are revealed through statistical tests. In addition, we performed an experiment with a frame called an n3D window (n3Dw) that is placed before the display such that a subject views the display through the opening of the frame. We found that the combination of a curve and the n3Dw causes n3D more effectively.

While visual size preferences regarding still objects have been investigated and linked to the “canonical size” effect—where preferred on-screen size was significantly related to objects’ real-world size—the visual size preferences related to moving images of natural scenes has not been researched. In this study, we measured the preferred size of moving images of natural scenes and short duration and investigated the effect of viewing distance on size preferences. Our results showed that the preferred size varied strongly depending on content, and we found moving images’ canonical size effect. The preferred size in images of scenery was significantly larger than in images of persons, and there was a positive correlation between the preferred size and the real-world physical size of the main subjects in the images. When the viewing distance was doubled, the preferred size increased about 10% as a ratio to screen size—in contrast to the findings of a previous study. While the rationale for these findings is not yet clear, our analysis suggests that neither the motion component in the images nor the nature of their background area are contributing factors. We suggest that environment, viewing distance, and screen size may contribute to this effect.

Due to the evolution of ultra-high-definition (UHD) technologies, viewers can enjoy more realistic contents. Furthermore, in order to maximize visual attraction, post-processing is conducted in commercial devices. In this paper, we propose a new terminology called visual preference to quantify viewer's preferences for sharpness- and contrast- enhanced UHD images in a particular viewing geometry. Visual preferences depend on the spatial characteristics and are affected by the viewing geometry of display like resolution, display size, and viewing distance. Therefore, we propose a method called visual preference assessment model that accounts for content enhancement features and diverse viewing geometry. By rigorous experiments, our proposed model outperforms other state-of-the-art models.

Touchscreen-based, multimodal graphics represent an area of increasing research in digital access for individuals with blindness or visual impairments; yet, little empirical research on the effects of screen size on graphical exploration exists. This work probes if and when more screen area is necessary in supporting a pattern-matching task. PURPOSE Larger touchscreens are thought to have distinct benefit over smaller touchscreens for the amount of space available to convey graphical information nonvisually. The current study investigates two questions: (1) Do screen size and grid density impact a user's accuracy on pattern-matching tasks? (2) Do screen size and grid density impact a user's time on task? METHODS Fourteen blind and visually impaired individuals were given a pattern-matching task to complete on either a 10.5-in tablet or a 5.1-in phone. The patterns consisted of five vibrating targets imposed on sonified grids that varied in density (higher density = more grid squares). At test, participants compared the touchscreen pattern with a group of physical, embossed patterns and selected the matching pattern. Participants were evaluated on time exploring the pattern on the device and their pattern-matching accuracy. Multiple and logistic regressions were performed on the data. RESULTS Device size, grid density, and age had no statistically significant effects on the model of pattern-matching accuracy. However, device size, grid density, and age had significant effects on the model for grid exploration. Using the phone, exploring low-density grids, and being older were indicative of faster exploration time. CONCLUSIONS A trade-off of time and accuracy exists between devices that seems to be task dependent. Users may find a tablet most useful in situations where the accuracy of graphic interpretation is important and is not limited by time. Smaller screen sizes afforded comparable accuracy performance to tablets and were faster to explore overall.

In our previous work, we proposed a user interface in which a user wears a projector and a depth camera on his or her head and performs touch operations on an image projected on a flat surface. By using the head-mounted projector, images are always projected in front of the user in the direction of the user&rsquo, s gaze. The image to be projected is changed according to the user&rsquo, s head pose so as to fix the superimposed image on the surface, which realizes a large effective screen size. In this paper, we conducted an experiment for evaluating the accuracy of registration by measuring the positional and rotational errors between the real world and the superimposed image using our experimental system. As a result, the mean absolute errors of translation were about 10 mm when the user stopped his head, and the delay was estimated to be about 0.2 s. We also discuss the limitations of our prototype and show the direction of future development.

The aim of present study was to improve the safety and the effectiveness of the in-vehicle display for camera monitor systems (CMS). The experimental factors were the size of the display and the location of the display. The participants were required to simultaneously carry out a tracking task and a rearward monitoring task. The evaluation measures were: the reaction time and the percentage correct reactions to the rearward stimuli, the tracking error, the car distance between own and the preceding car, and the horizontal neck movement. As a result, the reaction time, the percentage of correct reaction, the neck movement of CMS were better than the traditional side mirrors. It suggests CMS is safer and more effective than the side mirrors. Particularly, more than 5-in. display which was located at smaller visual angle had faster and more accurate reaction. This condition would be one of the design requirements for CMS.

In this work, we utilize visuo-haptic illusions to improve the perceived performance of encountered-type haptic devices, specifically shape displays, in virtual reality. Shape displays are matrices of actuated pins that travel vertically to render physical shapes; however, they have limitations such as low resolution, small display size, and low pin speed. To address these limitations, we employ illusions such as redirection, scaling, and retargeting that take advantage of the visual dominance effect, the idea that vision often dominates when senses conflict. Our evaluation of these techniques suggests that redirecting sloped lines with angles less than 40 degrees onto a horizontal line is an effective technique for increasing the perceived resolution of the display. Scaling up the virtual object onto the shape display by a factor less than 1.8x can also increase the perceived resolution. Finally, using vertical redirection a perceived 3x speed increase can be achieved.

Touch gestures on the screen of a wrist worn device are constrained by the size of the screen. Decoupling the gesture size from the screen size allows for larger gestures on smaller devices. Other approaches to decoupling screen size from gesture size on wrist worn devices support only a small set of gestures. We decouple screen size from gesture size by using an optical flow sensor. The user generates gestures by moving a finger over the optical flow sensor. Gestures can feasibly be detected through a small round window with a diameter of 3 mm. This window “dot” could be embedded in small wrist worn devices. A random forest trained on the EdgeWrite alphabet achieved 93% accuracy on 27 gestures generated using the optical flow sensor. We discuss the motivation for such a system and prove its feasibility using a prototype, noting that additional engineering work is needed to produce a small wrist-worn device based on a small optical flow sensor package.

Diverse aspect ratios of display devices require adaptation of the image content to be displayed on them. Image retargeting pertains to changing the size of an image to adapt to the aspect ratio and spatial resolution of the display device. This is achieved while preserving the salient or important information and thereby reducing visible artifacts in the retargeted image. Seam carving techniques remove or insert least energy seams, one pixel wide paths from top to bottom or left to right of an image, iteratively in order to achieve the target display size. These techniques highly depend on an energy measure of a pixel in an image. Here, we propose a novel technique of defining energy of a pixel, also known as significance map, using object proposal boxes with the probability of objects being present. Object proposal boxes are modeled using the Gaussian kernels. The generation of significance map can be executed on an average in just over a second for a given image. We show that the proposed significance map is able to capture salient region(s) of an image having different textured background and different noise levels. The significance map can be used with an image retargeting algorithm such as seam carving to achieve desired results. Quantitative assessment and comparison with the other state-of-the-art image retargeting techniques show that the proposed energy measure yields the best results for image retargeting using seam carving.

Current touch pen requires the special equipments to detect a touch and its price increases in proportion to the screen size. In this paper, we propose a method for detecting a touch and implementing a pen using the depth information. The proposed method obtains a background depth image using a depth camera and extracts an object by comparing a captured depth image with the background depth image. Also, we determine a touch if the depth value of the object is the same as the background and then provide the pen event. Using this method, we can implement a cheaper and more convenient touch pen.

Image retargeting is to re-represent the image, usually with a different image size to cater for the display size of the end-user (e.g., computer, smartphone). In this paper, we propose an image retargeting quality assessment scheme based on four quality factors and support vector regression. The accounted quality factors are of two categorizes: 1) shape distortions, they are visual unpleasant artifacts introduced by retargeting, e.g., a straight line may be retargeted as a curve, a circle may be retargeted as an ellipse, etc.; 2) visual content changes, they mainly refer to the loss of visual information due to retargeting. Both spatial and frequency information are used toward a complete assessment. The spatial quality factors measure shape distortions and visual content changes separately and independently, and therefore it is possible to control their relative importance to the overall assessment. Since spatial quality factors need image matching which may cause measurement error, another quality factor in frequency domain is also used. The overall image retargeting quality is contributed by the four quality measures collectively and machine learning is used accounts for such a combination, corresponding discussions are also provided for each factor. The effectiveness of the proposed scheme is verified with the publicly-available subject-rated database (comprising of diverse images and retargeting methods) and better performance (in terms of both accuracy and complexity) is achieved in comparison with the state of the art schemes. Formulated major quality factors (in both spatial and frequency domains) into IRQA.Identified shape distortion and proposed a measure for it.Proposed frequency domain estimator to alleviate the measurement error in spatial domain.Used machine learning to integrate different quality factors.

An intriguing aspect of picture perception is the viewer’s tolerance to variation in viewing position, perspective, and display size. These factors are also present in stereoscopic media, where there are additional parameters associated with the camera arrangement (e.g., separation, orientation). The predicted amount of depth from disparity can be obtained trigonometrically; however, perceived depth in complex scenes often differs from geometric predictions based on binocular disparity alone. To evaluate the extent and the cause of deviations from geometric predictions of depth from disparity in naturalistic scenes, we recorded stereoscopic footage of an indoor scene with a range of camera separations (camera interaxial (IA) ranged from 3 to 95 mm) and displayed them on a range of screen sizes. In a series of experiments participants estimated 3D distances in the scene relative to a reference scene, compared depth between shots with different parameters, or reproduced the depth between pairs of objects in the scene using reaching or blind walking. The effects of IA and screen size were consistently and markedly smaller than predicted from the binocular viewing geometry, suggesting that observers are able to compensate for the predicted distortions. We conclude that the presence of multiple realistic monocular depth cues drives normalization of perceived depth from binocular disparity. It is not clear to what extent these differences are due to cognitive as opposed to perceptual factors. However, it is notable that these normalization processes are not task specific; they are evident in both perception- and action-oriented tasks.

In the twenty-first century, everyone is a cameraman. Citizens challenge the news with evidence uploaded to social media, feature films stream online, and screen size varies depending on personal d...

Viewers of stereoscopic three-dimensional (3D) imagery can perceive the absolute size of objects within a scene. On larger screens, the perceptual size of objects commonly appears bigger than reality, which matches viewers’ expectations for big-screen, larger-than-life theatrical experiences. In contrast, the geometry involved in stereoscopic imaging can cause the perceptual size of objects to appear smaller than reality (miniaturization). Miniaturization can be distracting for viewers and is more extreme on smaller screens like 3D television and handheld 3D devices. A common misconception is that miniaturization occurs only when the stereo camera separation (interaxial) is larger than the human eye separation (interocular), or larger than 2.5 in. In this paper, counter examples of this misconception are provided, as well as an analytical framework that allows stereo camera operators to accurately predict what the miniaturization effect will be on any screen size. Example stereoscopic 3D images are shown to illustrate control of perceptual size.

Holographic displays and super multi-view (SMV) displays have been developed to solve the accommodation–vergence conflict that is responsible for visual fatigue caused by the 3D images that are generated by conventional three-dimensional (3D) displays upon which the eye cannot focus. However, holographic and SMV displays provide 3D images upon which the eye can readily focus so that the accommodation–vergence conflict does not occur. Because these two display techniques require the generation of a very large amount of image data, the high data bandwidth of microelectromechanical (MEMS) devices is effectively utilized. The present article describes the holographic display system that employs a MEMS spatial light modulator (SLM), which increases the screen size and viewing zone angle. Two SMV displays are also described, where one employs MEMS SLMs and the other an array of MEMS projectors. The resolution and the number of viewpoints of the SMV displays have increased. Moreover, the technique using a MEMS SLM to eliminate speckles from holographic reconstructed images is also described.

A multi-view autostereoscopic three-dimensional (3D) system is built by using a 2D display screen and a customized parallax-barrier shutter (PBS) screen. The shutter screen is controlled dynamically by address driving matrix circuit and it is placed in front of the display screen at a certain location. The system could achieve densest viewpoints due to its specially optical and geometric design which is based on concept of “eye space”. The resolution of 3D imaging is not reduced compared to 2D mode by using limited time division multiplexing technology. The diffraction effects may play an important role in 3D display imaging quality, especially when applied to small screen, such as iPhone screen etc. For small screen, diffraction effects may contribute crosstalk between binocular views, image brightness uniformity etc. Therefore, diffraction effects are analyzed and considered in a one-dimensional shutter screen model of the 3D display, in which the numerical simulation of light from display pixels on display screen through parallax barrier slits to each viewing zone in eye space, is performed. The simulation results provide guidance for criteria screen size over which the impact of diffraction effects are ignorable, and below which diffraction effects must be taken into account. Finally, the simulation results are compared to the corresponding experimental measurements and observation with discussion.

The small screen size of a smartwatch limits user experience when watching or interacting with media. We propose a supplementary tactile feedback system to enhance the user experience with a method unique to the smartwatch form factor. Our system has a deformable surface on the back of the watch face, allowing the visual scene on screen to extend into 2.5D physical space. This allows the user to watch and feel virtual objects, such as experiencing a ball bouncing against the wrist. We devised two controlled experiments to analyze the influence of tactile display resolution on the illusion of virtual object presence. Our first study revealed that on average, a taxel can render virtual objects between 70% and 138% of its own size without shattering the illusion. From the second study, we found visual and haptic feedback can be separated by 4.5mm to 16.2mm for the tested taxels. Based on the results, we developed a prototype (called RetroShape) with 4×4 10mm taxels using micro servo motors, and demonstrated its unique capability through a set of tactile-enhanced games and videos. A preliminary user evaluation showed that participants welcome RetroShape as a useful addition to existing smartwatch output.

We present HeatSpace, a system that records and empirically analyzes user behavior in a space and automatically suggests positions and sizes for new displays. The system uses depth cameras to capture 3D geometry and users' perspectives over time. To derive possible display placements, it calculates volumetric heatmaps describing geometric persistence and planarity of structures inside the space. It evaluates visibility of display poses by calculating a volumetric heatmap describing occlusions, position within users' field of view, and viewing angle. Optimal display size is calculated through a heatmap of average viewing distance. Based on the heatmaps and user constraints we sample the space of valid display placements and jointly optimize their positions. This can be useful when installing displays in multi-display environments such as meeting rooms, offices, and train stations.

Recent demonstrations of high dynamic range (HDR) television have shown that superb images are possible. With the emergence of an HDR television production standard (ITU-R Recommendation BT.2100) last year, HDR television production is poised to take off. However research to date has focused principally on HDR image display only under “dark” viewing conditions. HDR television will need to be displayed at varying brightness and under varying illumination (for example to view sport in daytime or on mobile devices). We know, from common practice with conventional TV, that the rendering intent (gamma) should change under brighter conditions, although this is poorly quantified. For HDR the need to render images under varying conditions is all the more acute. This paper seeks to explore the issues surrounding image display under varying conditions. It also describes how visual adaptation is affected by display brightness, surround illumination, screen size and viewing distance. Existing experimental results are presented and extended to try to quantify these effects. Using the experimental results it is described how HDR images may be displayed so that they are perceptually equivalent under different viewing conditions. A new interpretation of the experimental results is reported, yielding a new, luminance invariant model for the appropriate display “gamma”. In this way the consistency of HDR image reproduction should be improved, thereby better maintaining “creative intent” in television.

The appropriate visual search techniques and visual display methods lead to the most effective and quickest way of extracting information during visual search tasks. Visual search time and performance in visual display terminals can be influenced by various parameters, such as an amount of the clutter objects and the screen size. This paper investigated the visual search techniques and performance using radar interface with different symbols that vary in color and features. Thirty-six subjects participated in the study and experiments were performed on separate monitors whose screen size is 7, 15 and 21 in. , the visual angles are experimentally set to be 45; 55; 65; 75 and 85 min of arc. This article took into considerations various performance variables such as completion time, fixation duration etc. to complete the visual search investigation. It was confirmed that the accuracy is highly affected by many clutter objects in the region surrounding a target.

Online experimentation is emerging in many areas of cognitive psychology as a viable alternative or supplement to classical in-lab experimentation. While performance- and reaction-time-based paradigms are covered in recent studies, one instrument of cognitive psychology has not received much attention up to now: eye tracking. In this study, we used JavaScript-based eye tracking algorithms recently made available by Papoutsaki et al. (International Joint Conference on Artificial Intelligence, 2016) together with consumer-grade webcams to investigate the potential of online eye tracking to benefit from the common advantages of online data conduction. We compared three in-lab conducted tasks (fixation, pursuit, and free viewing) with online-acquired data to analyze the spatial precision in the first two, and replicability of well-known gazing patterns in the third task. Our results indicate that in-lab data exhibit an offset of about 172 px (15% of screen size, 3.94° visual angle) in the fixation task, while online data is slightly less accurate (18% of screen size, 207 px), and shows higher variance. The same results were found for the pursuit task with a constant offset during the stimulus movement (211 px in-lab, 216 px online). In the free-viewing task, we were able to replicate the high attention attribution to eyes (28.25%) compared to other key regions like the nose (9.71%) and mouth (4.00%). Overall, we found web technology-based eye tracking to be suitable for all three tasks and are confident that the required hard- and software will be improved continuously for even more sophisticated experimental paradigms in all of cognitive psychology.

Glaucoma is the leading cause of irreversible blindness worldwide. Due to its wide prevalence, effective screening tools are necessary. The purpose of this project is to design and evaluate a system that enables portable, cost effective, smartphone based visual field screening based on frequency doubling technology. The system is comprised of an Android smartphone to display frequency doubling stimuli and handle processing, a Bluetooth remote for user input, and a virtual reality headset to simulate the exam. The LG Nexus 5 smartphone and BoboVR Z3 virtual reality headset were used for their screen size and lens configuration, respectively. The system is capable of running the C-20, N-30, 24-2, and 30-2 testing patterns. Unlike the existing system, the smartphone FDT tests both eyes concurrently by showing the same background to both eyes but only displaying the stimulus to one eye at a time. Both the Humphrey Zeiss FDT and the smartphone FDT were tested on five subjects without a history of ocular disease with the C-20 testing pattern. The smartphone FDT successfully produced frequency doubling stimuli at the correct spatial and temporal frequency. Subjects could not tell which eye was being tested. All five subjects preferred the smartphone FDT to the Humphrey Zeiss FDT due to comfort and ease of use. The smartphone FDT is a low-cost, portable visual field screening device that can be used as a screening tool for glaucoma.

Head Mounted Displays (HMDs) anecdotally exhibit a higher rate of cybersickness, motion-sickness like symptoms due to visual stimuli, than virtual reality systems that employ large screens. Yet, there have been relatively few multi-display studies, and frequently factors other than the display varied between conditions. We controlled for these additional factors in three experiments which considered HMDs weight, perceived screen size, and rendering mode. The HMD weight experiment had no effect on cybersickness, with p < 0.88. This is of benefit to HMD developers as it signifies that additional weight in the hardware is not cause for concern. While screen size and field of view (FOV) are often used interchangeably, the FOV has a strong effect independent of screen size. The perceived screen size experiment had no effect on cybersickness, with p < 0.66. This benefits cybersickness researchers, as it signifies that the results from monitor experiments can be compared directly with the results from large screen experiments, assuming the remaining factors are held constant. The rendering experiment, with stereo and mono rendering, had no effect on cybersickness, with p = 0.22. Since the HMD weight and screen size experiments used the same FOV, application, and navigation paradigm, they were compared for possible effects. Initially, we found a significant effect on cybersickness. After normalizing using the average change when a part of the real world is seen, such as in large screens, there is no longer a statistical difference (p < 0.77).

People's ability to remember and recall spatial information can be harnessed to improve navigation and search performances in interactive systems. In this paper, we investigate how display size and input modality influence spatial memory, especially in relation to efficiency and user satisfaction. Based on an experiment with 28 participants, we analyze the effect of three input modalities (trackpad, direct touch, and gesture-based motion controller) and two display sizes (10.6" and 55") on people's ability to navigate to spatially spread items and recall their positions. Our findings show that the impact of input modality and display size on spatial memory is not straightforward, but characterized by trade-offs between spatial memory, efficiency, and user satisfaction. published

Seam carving is a content-aware multimedia retargeting technique to adaptively resize multimedia data for different display sizes. However, it can also be used to remove objects from digital object or video for malicious purposes. In this paper, a forensics hash-based tampering detection and localization approach is proposed for seam carving-based video retargeting. It extracts the invariant Speeded-up Robust Feature points from every spatiotemporal image to represent the matching surface, and the relative position change of the neighboring matching surface is used to build the forensic hash in a compact and scalable way. Experimental results show that the proposed forensics approach can effectively estimate the exact amount and rough locations of deleted seam carving surfaces. It achieves desirable detection performance even when there are frames deleted. If the hash length is reasonably increased, it can estimate the rough location and exact amount of deleted frames. Moreover, the built forensics hash is of good robustness, scalability, and compactness. Copyright © 2014 John Wiley & Sons, Ltd.