Security and human computer interfaces

Computer users are exposed to technology mainly through user interfaces. Most users' perceptions are based on their experience with these interfaces. HCI (human computer interaction) is concerned with these interfaces and how they can be improved. Considerable research has been conducted and major advances have been made in the area of HCI. Information security is becoming increasingly important and more complex as business is conducted electronically. However, state-of-the-art security-related product development has ignored general aspects of HCI. The objective of this paper is to promote and enable security awareness of end-users in their interaction with computer systems. It thus aims to consolidate and integrate the two fields of information security and HCI. HCI as a research discipline is a well developed field of study, and the authors are of the opinion that the use of security technologies can be significantly enhanced by employing proven HCI concepts in the design of these technologies. In order to achieve this, various criteria for a successful HCI in a security-specific environment will be examined. Part of the Windows XP Internet Connection Firewall will be used as a case study and analysed according to these criteria, and recommendations will be made.     

Brain-computer interfaces for human gait restoration

In this review article,we present more than a decade of our work on the development of brain-computer interface(BCI)systems for the restoration of walking follo...     

Stereoscopic ray-tracing

In this paper, we describe a method to create an approximate ray-traced stereoscopic pair by transforming a fully raytraced left-eye view into an inferred right-eye view. Performance results from evaluating several random scenes, which indicate that the second view in a stereoscopic image can be computed with as little as 5% of the effort required to fully ray-trace the first view, are presented. We also discuss worst-case performance of our algorithm and demonstrate that our technique is always at least as efficient as two passes of a standard ray-tracer.     

Stereoscopic Segmentation

We cast the problem of multiframe stereo reconstruction of a smooth shape as the global region segmentation of a collection of images of the scene. Dually, the problem of segmenting multiple calibrated images of an object becomes that of estimating the solid shape that gives rise to such images. We assume that the radiance of the scene results in piecewise homogeneous image statistics. This simplifying assumption covers Lambertian scenes with constant albedo as well as fine homogeneous textures, which are known challenges to stereo algorithms based on local correspondence. We pose the segmentation problem within a variational framework, and use fast level set methods to find the optimal solution numerically. Our algorithm does not work in the presence of strong photometric features, where traditional reconstruction algorithms do. It enjoys significant robustness to noise under the assumptions it is designed for.     

Challenges in speech-based human–computer interfaces

In this article we present an overview of our current research activities falling into the scope of developing advanced spoken language dialogue systems. These systems need to react flexibly and adaptively depending on the current status of the user and the situation of use. In particular, they require emotion recognition and adaptive dialogue management techniques. Advanced dialogue systems also need proactive capabilities to act as intelligent assistants to their users.     

Stereoscopic 3D displays and human performance: A comprehensive review

To answer the question: “what is 3D good for?” we reviewed the body of literature concerning the performance implications of stereoscopic 3D (S3D) displays versus non-stereo (2D or monoscopic) displays. We summarized results of over 160 publications describing over 180 experiments spanning 51 years of research in various fields including human factors psychology/engineering, human–computer interaction, vision science, visualization, and medicine. Publications were included if they described at least one task with a performance-based experimental evaluation of an S3D display versus a non-stereo display under comparable viewing conditions. We classified each study according to the experimental task(s) of primary interest: (a) judgments of positions and/or distances; (b) finding, identifying, or classifying objects; (c) spatial manipulations of real or virtual objects; (d) navigation; (e) spatial understanding, memory, or recall and (f) learning, training, or planning. We found that S3D display viewing improved performance over traditional non-stereo (2D) displays in 60% of the reported experiments. In 15% of the experiments, S3D either showed a marginal benefit or the results were mixed or unclear. In 25% of experiments, S3D displays offered no benefit over non-stereo 2D viewing (and in some rare cases, harmed performance). From this review, stereoscopic 3D displays were found to be most useful for tasks involving the manipulation of objects and for finding/identifying/classifying objects or imagery. We examine instances where S3D did not support superior task performance. We discuss the implications of our findings with regard to various fields of research concerning stereoscopic displays within the context of the investigated tasks.     

Sketching interfaces: toward more human interface design

Researchers at University of California, Berkeley and Carnegie Mellon University have designed, implemented, and evaluated SILK (Sketching Interfaces Like Krazy), an informal sketching tool that combines many of the benefits of paper-based sketching with the merits of current electronic tools. With SILK, designers can quickly sketch an interface using an electronic pad and stylus, and SILK recognizes widgets and other interface elements as the designer draws them. Unlike paper-based sketching, however, designers can exercise these elements in their sketchy state. For example, a sketched scroll-bar is likely to contain an elevator or thumbnail, the small rectangle a user drags with a mouse. In a paper sketch, the elevator would just sit there, but in a SILK sketch, designers can drag it up and down, which lets them test component or widget behavior. SILK also supports the creation of storyboards-the arrangement of sketches to show how design elements behave, such as how a dialog box appears when the user activates a button. Storyboards are important because they give designers a way to show colleagues, customers, or end users early on how an interface will behave     

浅谈3D立体电视

立体电视又称为三维电视(3D TV),准确的术语应该是Stereoscopies Television,它与现行电视的主要区别是,现行电视只传送一个平面的信息,而立体电视传送的是物体的浓度信息,它也是利用人眼的立体视觉特性来产生立体图像的.本文阐述了3D立体电视的实现方式,探讨了其未来的发展以及面临的瓶颈问题.     

Simultaneous Generation of Stereoscopic Views

Currently almost all computer graphic stereoscopic images are generated by doubling the work required to create a single image. In this paper we derive and analyze algorithms for simultaneous generation of the two views necessary for a stereoscopic image. We begin with a discussion of the similarities of the two perspective views of a stereo pair. Following this, several graphics algorithms that have been optimized from known single-view methods are described and performance results obtained from testing the new stereo algorithms against the originals are presented.     

Depth Mapping for Stereoscopic Videos

Stereoscopic videos have become very popular in recent years. Most of these videos are developed primarily for viewing on large screens located at some distance away from the viewer. If we watch these videos on a small screen located near to us, the depth range of the videos will be seriously reduced, which can significantly degrade the 3D effects of these videos. To address this problem, we propose a linear depth mapping method to adjust the depth range of a stereoscopic video according to the viewing configuration, including pixel density and distance to the screen. Our method tries to minimize the distortion of stereoscopic image contents after depth mapping, by preserving the relationship of neighboring features and preventing line and plane bending. It also considers the depth and motion coherences. While depth coherence ensures smooth changes of the depth field across frames, motion coherence ensures smooth content changes across frames. Our experimental results show that the proposed method can improve the stereoscopic effects while maintaining the quality of the output videos.     

Organizing human factors knowledge for the evaluation and design of interfaces

This paper presents research conducted in the area of human factors knowledge collection and organization. Providing that a large amountof human factors engineering data is available now concerning user interface aspects, this research started from the following question: Can this knowledge be transferred to user interface designers, and by which means can this be done? An important part of human factors knowledge is included in recommendations and guidelines. It is the problems with that type of knowledge that this paper focuses on. A first attempt to tackle some of these problems is made by offering a generic model for deciphering recommendations into rules. This model stresses the importance of attributes such as human factors criteria, classes of premises, and conclusions, as well as interface objects. Definitions of criteria for organizing recommendations are offered, and a few examples of rule‐based reasoning are provided. The remaining problems with a rule approach are then discussed according to two dimensions: intrinsic problems and usage problems. In addition, it appears that an approach based on literature recommendations is not sufficient. Other areas that need further work are described, particularly concerning task and interface modelling, and human factors expertise modelling. The paper concludes on the limits and benefits of such an approach.     

Stereoscopic video images for telerobotic applications

This article addresses the use of stereoscopic images in teleoperated tasks. Depth perception is a key point in the ability to skillfully manipulate in remote environments. Displaying three‐dimensional images is a complex process but it is possible to design a teleoperation interface that displays stereoscopic images to assist in manipulation tasks. The appropriate interface for image viewing must be chosen and the stereoscopic video cameras must be calibrated so that the image disparity is natural for the observer. Attention is given to the calculation of stereoscopic image disparity, and suggestions are made as to the limits within which adequate stereoscopic image perception takes place. The authors have designed equipment for image visualization in teleoperated systems. These devices are described and their performance evaluated. Finally, an architecture for the transmission of stereoscopic video images via network is proposed, which in the future will substitute for current image processing devices. © 2005 Wiley Periodicals, Inc.     

Stereoscopic oil paintings from RGBD images

Multimedia Tools and Applications - Stroke-based rendering is one of the major approaches for creating synthetic paintings, but with only a minor attention so far to stereo painting synthesis. In...     

Body-based interfaces

This research explores different ways to use features of one's own body for interacting with computers. Such "body-based" interfaces may find good uses in wearable computing or virtual reality systems as part of a 3D multi-modal interface in the future, freeing the user from holding interaction devices. Four types of body-based interfaces have been identified: Body-inspired metaphor (BIM); Body-as-interaction-surface (BAIS); Mixed mode (MM); and Object mapping (OM). These four body-based interfaces were applied to a few different applications (and associated tasks) and were tested for their performance and preference. It was generally found that, among the four, the BIM exhibited low error rates, but produced relatively longer task completion times and significant fatigue. The BAIS method had the contrasting character of higher error rates, but shorter task completion times and lower intuitiveness. The OM method exhibited high error rates, longer completion times, and much fatigue. Overall, the MM was superior in terms of both performance and preference as it combined the merits of the above three methods. Thus, it is expected, for applications with many associated tasks, a careful division of tasks among those that have natural semantic links to body parts and those that do not, is necessary to design the most performing body-based interface.     

Shape-changing interfaces

The design of physical interfaces has been constrained by the relative akinesis of the material world. Current advances in materials science promise to change this. In this paper, we present a foundation for the design of shape-changing surfaces in human–computer interaction. We provide a survey of shape-changing materials and their primary dynamic properties, define the concept of soft mechanics within an HCI context, and describe a soft mechanical alphabet that provides the kinetic foundation for the design of four design probes: Surflex, SpeakCup, Sprout I/O, and Shutters. These probes explore how individual soft mechanical elements can be combined to create large-scale transformable surfaces, which can alter their topology, texture, and permeability. We conclude by providing application themes for shape-changing materials in HCI and directions for future work.     

Expressive interfaces

Analysis of expressiveness in human gesture can lead to new paradigms for the design of improved human-machine interfaces, thus enhancing users participation and experience in mixed reality applications and context-aware mediated environments. The development of expressive interfaces decoding the highly affective information gestures convey opens novel perspectives in the design of interactive multimedia systems in several application domains: performing arts, museum exhibits, edutainment, entertainment, therapy, and rehabilitation. This paper describes some recent developments in our research on expressive interfaces by presenting computational models and algorithms for the real-time analysis of expressive gestures in human full-body movement. Such analysis is discussed both as an example and as a basic component for the development of effective expressive interfaces. As a concrete result of our research, a software platform named EyesWeb was developed (). Besides supporting research, EyesWeb has also been employed as a concrete tool and open platform for developing real-time interactive applications.     

On interfaces

The nature of interfaces is discussed. It is recommended that modern software approaches to interfaces (such as abstract data types) be extended to interfaces of all kinds. These interfaces can and should be developed at the level of abstraction appropriate to the interacting elements, rather than at the level of their lowest common denominator, which is frequently the case. It is proposed that for an interface to exist at any level of abstraction, there must be an operational framework that implements that level of abstraction and within which the interfacing elements interact. Four tasks required for the development of interfaces are described. The traditional classification of interfaces as hardware/software, software/software, and hardware/hardware is found wanting and a new partitioning is suggested—structural or interpretive interfaces, symbolic interfaces, and physical interfaces. Standards and scientific and engineering theories are shown to define levels of abstraction for general interfaces in much the same way that programming languages do for software interfaces. Implications for software engineering and concurrent engineering are explored.     

Stereoscopic video synthesis from a monocular video

This paper presents an automatic and robust approach to synthesize stereoscopic videos from ordinary monocular videos acquired by commodity video cameras. Instead of recovering the depth map, the proposed method synthesizes the binocular parallax in stereoscopic video directly from the motion parallax in monocular video, The synthesis is formulated as an optimization problem via introducing a cost function of the stereoscopic effects, the similarity, and the smoothness constraints. The optimization selects the most suitable frames in the input video for generating the stereoscopic video frames. With the optimized selection, convincing and smooth stereoscopic video can be synthesized even by simple constant-depth warping. No user interaction is required. We demonstrate the visually plausible results obtained given the input clips acquired by ordinary handheld video camera.