Pervasive and standalone computing: The perceptual effects of variable multimedia quality.

The introduction of multimedia on pervasive and mobile communication devices raises a number of perceptual quality issues, however, limited work has been done examining the 3-way interaction between use of equipment, quality of perception and quality of service. Our work measures levels of informational transfer (objective) and user satisfaction (subjective)when users are presented with multimedia video clips at three different frame rates, using four different display devices, simulating variation in participant mobility. Our results will show that variation in frame-rate does not impact a user’s level of information assimilation, however, does impact a users’ perception of multimedia video ‘quality’. Additionally, increased visual immersion can be used to increase transfer of video information, but can negatively affect the users’ perception of ‘quality’. Finally, we illustrate the significant affect of clip-content on the transfer of video, audio and textual information, placing into doubt the use of purely objective quality definitions when considering multimedia presentations

Virtual Reality-Based Experiential Model for Lost Historic Buildings

Historic buildings have always been facing severe threats of destruction. Historic buildings are the physical links to our past, and help in forming and imprinting a cultural memory within us. However, when a building gets totally destroyed, the resources available to learn about the past are very limited. The archaeological relics, photographs, sketches, textural records, etc. fail to create a complete picture of the lost structure in our mind due to their unorganized nature and lack of possibility to explore in and around the building. Virtual reality (VR) is an interactive technology that allows people to virtually walk inside built environments using digital tools, and enables us to experience them on a human scale. Virtual heritage (VH) applications have been a popular research area among the Architects, Archaeologists and Historians for more than two decades. Virtual heritage projects, excluding projects developed in the entertainment industry, are predominantly developed by researchers and academicians. These virtual heritage projects mainly focus on either the ‘Process’ (3D reconstruction mechanism) or the ‘Products’ (Virtual Reality systems) but do not consider the end-users, i.e. the ‘People’ going to use the system. Humans are cultural organisms and their cultural and demographical aspects differ from each other and hence the cultural interpretation, perception and reaction are subjective. Different cultural environment poses different meanings to different people. Hence, it is crucial to identify what end-users’ interests are in a virtual heritage environment in order to effectively educate about the past. This research attempts to investigate the experiences of users when a first-person Virtual Reality-based model of a lost building is presented to the visitors of the museum. the entertainment industry, are predominantly developed by researchers and academicians. These virtual heritage projects mainly focus on either the ‘Process’ (3D reconstruction mechanism) or the ‘Products’ (Virtual Reality systems) but do not consider the end-users, i.e. the ‘People’ going to use it. Humans are cultural organisms and their cultural and demographical aspects differ from each other and hence the cultural interpretation, perception and reaction are subjective. Different cultural environment poses different meanings to different people. Hence, it is crucial to identify what end-users’ interests are in a virtual heritage environment in order to effectively educate about the past. This research attempts to investigate the experiences of users when a first-person Virtual Reality-based model of a lost building is presented to the visitors of the museum

Seamless and Secure VR: Adapting and Evaluating Established Authentication Systems for Virtual Reality

Virtual reality (VR) headsets are enabling a wide range of new opportunities for the user. For example, in the near future users may be able to visit virtual shopping malls and virtually join international conferences. These and many other scenarios pose new questions with regards to privacy and security, in particular authentication of users within the virtual environment. As a first step towards seamless VR authentication, this paper investigates the direct transfer of well-established concepts (PIN, Android unlock patterns) into VR. In a pilot study (N = 5) and a lab study (N = 25), we adapted existing mechanisms and evaluated their usability and security for VR. The results indicate that both PINs and patterns are well suited for authentication in VR. We found that the usability of both methods matched the performance known from the physical world. In addition, the private visual channel makes authentication harder to observe, indicating that authentication in VR using traditional concepts already achieves a good balance in the trade-off between usability and security. The paper contributes to a better understanding of authentication within VR environments, by providing the first investigation of established authentication methods within VR, and presents the base layer for the design of future authentication schemes, which are used in VR environments only

Distributed multimedia quality: The user perspective

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Distributed multimedia supports a symbiotic infotainment duality, i.e. the ability to transfer information to the user, yet also provide the user with a level of satisfaction. As multimedia is ultimately produced for the education and / or enjoyment of viewers, the user’s-perspective concerning the presentation quality is surely of equal importance as objective Quality of Service (QoS) technical parameters, to defining distributed multimedia quality. In order to extensively measure the user-perspective of multimedia video quality, we introduce an extended model of distributed multimedia quality that segregates quality into three discrete levels: the network-level, the media-level and content-level, using two distinct quality perspectives: the user-perspective and the technical-perspective. Since experimental questionnaires do not provide continuous monitoring of user attention, eye tracking was used in our study in order to provide a better understanding of the role that the human element plays in the reception, analysis and synthesis of multimedia data. Results showed that video content adaptation, results in disparity in user video eye-paths when: i) no single / obvious point of focus exists; or ii) when the point of attention changes dramatically. Accordingly, appropriate technical- and user-perspective parameter adaptation is implemented, for all quality abstractions of our model, i.e. network-level (via simulated delay and jitter), media-level (via a technical- and user-perspective manipulated region-of-interest attentive display) and content-level (via display-type and video clip-type). Our work has shown that user perception of distributed multimedia quality cannot be achieved by means of purely technical-perspective QoS parameter adaptation

The usage of fully immersive head-mounted displays in social everyday contexts

Technology often evolves from decades of research in university and industrial laboratories and changes people's lives when it becomes available to the masses. In the interaction between technology and consumer, established designs in the laboratory environment must be adapted to the needs of everyday life. This paper deals with the challenges arising from the development of fully immersive Head Mounted Displays (HMD) in laboratories towards their application in everyday contexts. Research on virtual reality (VR) technologies spans over 50 years and covers a wide field of topics, e.g., technology, system design, user interfaces, user experience or human perception. Other disciplines such as psychology or the teleoperation of robots are examples for users of VR technology. The work in the previous examples was mainly carried out in laboratories or highly specialized environments. The main goal was to generate systems that are ideal for a single user to conduct a particular task in VR. The new emerging environments for the use of HMDs range from private homes to offices to convention halls. Even in public spaces such as public transport, cafés or parks, immersive experiences are possible. However, current VR systems are not yet designed for these environments. Previous work on problems in the everyday environment deals with challenges such as preventing the user from colliding with a physical object. However, current research does not take into account the new social context for an HMD user associated with these environments. Several people who have different roles are around the user in these contexts. In contrast to laboratory scenarios, the non-HMD user, for example, does not share the task with or is aware of the state of the HMD user in VR. This thesis contributes to the challenges introduced by the social context. For this purpose I offer solutions to overcome the visual separation of the HMD user. I also suggest methods for investigating and evaluating the use of HMDs suitable for everyday context. First, we present concepts and insights to overcome the challenges arising from an HMD covering the user's face. In the private context, e.g., living rooms, one of the main challenges is the need for an HMD user to take off the HMD to be able to communicate with others. Reasons for taking off the HMD are the visual exclusion of the surrounding world for HMD users and the HMD covering the users' face, hindering communication. Additionally, the Non-HMD users do not know about the virtual world the HMD user is acting in. Previous work suggests to visualize the bystanding Non-HMD user or its actions in VR to address such challenges. The biggest advantage of a fully immersive experience, however, is the full separation from the physical surrounding with the ultimate goal of being at another place. Therefore I argue not to integrate a non-HMD users directly into VR. I introduce the approach of using a shared surface that provides a common basis for information and interaction between a non-HMD and a HMD user. Such a surface can be utilized by using a smartphone. The same information is presented to the HMD in VR and the Non-HMD user on the shared surface in the same physical position, enabling joint interaction at the surface. By examining four feedback modalities, we provide design guidelines for touch interaction. The guidelines support interaction design with such a shared surface by an HMD user. Further, we explore the possibility to inform the Non-HMD user about the user's state during a mixed presence collaboration, e.g., if the HMD user is inattentive to the real world. For this purpose I use a frontal display attached to the HMD. In particular we explore the challenges of disturbed socialness and reduced collaboration quality, by presenting the users state on the front facing display. In summary, our concepts and studies explore the application of a shared surface to overcome challenges in a co-located mixed presence collaboration. Second, we look at the challenges of using HMDs in a public environment that have not yet been considered. The use of HMDs in these environments is becoming a reality due to the current development of HMDs, which contain all necessary hardware in one portable device. Related work, in particular, the work on public displays, already addresses the interaction with technology in public environments. The form factor of the HMD, the need to take an HMD onto the head and especially the visual and mental exclusion of the HMD user are new and not yet understood challenges in these environments. We propose a problem space for semi-public (e.g., conference rooms) and public environments (e.g., market places). With an explorative field study, we gain insight into the effects of the visual and physical separation of an HMD user from surrounding Non-HMD users. Further, we present a method that helps to design and evaluate the unsupervised usage of HMDs in public environments, the \emph{audience funnel flow model for HMDs}. Third, we look into methods that are suitable to monitor and evaluate HMD-based experiences in the everyday context. One core measure is the experience of being present in the virtual world, i.e., the feeling of ``being there''. Consumer-grade HMDs are already able to create highly immersive experiences, leading to a strong presence experience in VR. Hence we argue it is important to find and understand the remaining disturbances during the experience. Existing methods from the laboratory context are either not precise enough, e.g, questionnaires, to find these disturbances or cause high effort in their application and evaluation, e.g., physiological measures. In a literature review, we show that current research heavily relies on questionnaire-based approaches. I improve current qualitative approaches -- interviews, questionnaires -- to make the temporal variation of a VR experience assessable. I propose a drawing method that recognizes breaks in the presence experience. Also, it helps the user in reflecting an HMD-based experience and supports the communication between an interviewer and the HMD user. In the same paper, we propose a descriptive model that allows the objective description of the temporal variations of a presence experience from beginning to end. Further, I present and explore the concept of using electroencephalography to detect an HMD user's visual stress objectively. Objective detection supports the usage of HMDs in private and industrial contexts, as it ensures the health of the user. With my work, I would like to draw attention to the new challenges when using virtual reality technologies in everyday life. I hope that my concepts, methods and evaluation tools will serve research and development on the usage of HMDs. In particular, I would like to promote the use in the everyday social context and thereby create an enriching experience for all.Technologie entwickelt sich oft aus jahrzehntelanger Forschung in Universitäts- und Industrielabors und verändert das Leben der Menschen, wenn sie für die Masse verfügbar wird. Im Zusammenspiel von Technik und Konsument müssen im Laborumfeld etablierte Designs an die Bedürfnisse des Alltags angepasst werden. Diese Arbeit beschäftigt sich mit den Herausforderungen, die sich aus der Entwicklung voll immersiver Head Mounted Displays (HMD) in Labors, hin zu ihrer Anwendung im täglichen Kontext ergeben. Die Forschung zu Virtual-Reality-Technologien erstreckt sich über mehr als 50 Jahre und deckt ein breites Themenspektrum ab, wie zum Beispiel Technologie, Systemdesign, Benutzeroberflächen, Benutzererfahrung oder menschliche Wahrnehmung. Andere Disziplinen wie die Psychologie oder die Teleoperation von Robotern sind Beispiele für Anwender von VR Technologie. in der Vergangenheit Arbeiten wurden Arbeiten mit VR Systemen überwiegend in Labors oder hochspezialisierten Umgebungen durchgeführt. Der Großteil dieser Arbeiten zielte darauf ab, Systeme zu generieren, die für einen einzigen Benutzer ideal sind, um eine bestimmte Aufgabe in VR durchzuführen. Die neu aufkommenden Umgebungen für den Einsatz von HMDs reichen vom privaten Haushalt über Büros bis hin zu Kongresssälen. Auch in öffentlichen Räumen wie öffentlichen Verkehrsmitteln, Cafés oder Parks sind immersive Erlebnisse möglich. Allerdings sind die aktuellen VR Systeme noch nicht für diese Umgebungen ausgelegt. Vorangegangene Arbeiten zu den Problemen im Alltags Umfeld befassen sich daher mit Herausforderungen, wie der Vermeidung von Kollisionen des Benutzers mit einem physischen Objekt. Die aktuelle Forschung berücksichtigt allerdings nicht den neuen sozialen Kontext für einen HMD-Anwender, der mit den Alltagsumgebungen verbunden ist. Mehrere Personen, die unterschiedliche Rollen haben, sind in diesen Kontexten um den Benutzer herum. Im Gegensatz zu Szenarien im Labor teilt der Nicht-HMD-Benutzer beispielsweise nicht die Aufgabe und ist sich nicht über den Zustand des HMD-Benutzers in VR bewusst. Diese Arbeit trägt zu den Herausforderungen bei, die durch den sozialen Kontext eingeführt werden. Zu diesem Zweck bieten ich in meiner Arbeit Lösungen an, um die visuelle Abgrenzung des HMD-Anwenders zu überwinden. Ich schlage zudem Methoden zur Untersuchung und Bewertung des Einsatzes von HMDs in öffentlichen Bereichen vor. Zuerst präsentieren wir Konzepte und Erkenntnisse, um die Herausforderungen zu meistern, die sich durch das HMD ergeben, welches das Gesicht des Benutzers abdeckt. Im privaten Bereich, z.B. in Wohnzimmern, ist eine der größten Herausforderungen die Notwendigkeit, dass der HMD-Nutzer das HMD abnimmt, um mit anderen kommunizieren zu können. Gründe für das Abnehmen des HMDs sind die visuelle Ausgrenzung der Umgebung für die HMD-Anwender und das HMD selbst, welches das Gesicht des Anwenders bedeckt und die Kommunikation behindert. Darüber hinaus wissen die Nicht-HMD-Benutzer nichts über die virtuelle Welt, in der der HMD-Benutzer handelt. Bisherige Konzepte schlugen vor, den Nicht-HMD-Benutzer oder seine Aktionen in VR zu visualisieren, um diese Herausforderungen zu adressieren. Der größte Vorteil einer völlig immersiven Erfahrung ist jedoch die vollständige Trennung der physischen Umgebung mit dem ultimativen Ziel, an einem anderen Ort zu sein. Daher schlage ich vor die Nicht-HMD-Anwender nicht direkt in VR einzubinden. Stattdessen stelle ich den Ansatz der Verwendung einer geteilten Oberfläche vor, die eine gemeinsame Grundlage für Informationen und Interaktion zwischen einem Nicht-HMD und einem HMD-Benutzer bietet. Eine geteile Oberfläche kann etwa durch die Verwendung eines Smartphones realisiert werden. Eine solche Oberfläche präsentiert dem HMD und dem Nicht-HMD-Benutzer an der gleichen physikalischen Position die gleichen Informationen. Durch die Untersuchung von vier Feedbackmodalitäten stellen wir Designrichtlinien zur Touch-Interaktion zur Verfügung. Die Richtlinien ermöglichen die Interaktion mit einer solchen geteilten Oberfläche durch einen HMD-Anwender ermöglichen. Weiterhin untersuchen wir die Möglichkeit, den Nicht-HMD-Benutzer während einer Zusammenarbeit über den Zustand des HMD Benutzers zu informieren, z.B., wenn der HMD Nutzer gegenüber der realen Welt unachtsam ist. Zu diesem Zweck schlage ich die Verwendung eines frontseitigen Displays, das an dem HMD angebracht ist. Zusätzlich bieten unsere Studien Einblicke, die den Designprozess für eine lokale, gemischt präsente Zusammenarbeit unterstützen. Zweitens betrachten wir die bisher unberücksichtigten Herausforderungen beim Einsatz von HMDs im öffentlichen Umfeld. Ein Nutzung von HMDs in diesen Umgebungen wird durch die aktuelle Entwicklung von HMDs, die alle notwendige Hardware in einem tragbaren Gerät enthalten, zur Realität. Verwandte Arbeiten, insbesondere aus der Forschung an Public Displays, befassen sich bereits mit der Nutzung von Display basierter Technologien im öffentlichen Kontext. Der Formfaktor des HMDs, die Notwendigkeit ein HMD auf den Kopf zu Ziehen und vor allem die visuelle und mentale Ausgrenzung des HMD-Anwenders sind neue und noch nicht verstanden Herausforderung in diesen Umgebungen. Ich schlage einen Design Space für halböffentliche (z.B. Konferenzräume) und öffentliche Bereiche (z.B. Marktplätze) vor. Mit einer explorativen Feldstudie gewinnen wir Einblicke in die Auswirkungen der visuellen und physischen Trennung eines HMD-Anwenders von umliegenden Nicht-HMD-Anwendern. Weiterhin stellen wir eine Methode vor, die unterstützt, den unbeaufsichtigten Einsatz von HMDs in öffentlichen Umgebungen zu entwerfen und zu bewerten, das \emph{audience funnel flow model for HMDs}. Drittens untersuchen wir Methoden, die geeignet sind, HMD-basierte Erfahrungen im Alltagskontext zu überwachen und zu bewerten. Eine zentrale Messgröße ist die Erfahrung der Präsenz in der virtuellen Welt, d.h. das Gefühl des "dort seins". HMDs für Verbraucher sind bereits in der Lage, hoch immersive Erlebnisse zu schaffen, was zu einer starken Präsenzerfahrung im VR führt. Daher argumentieren wir, dass es wichtig ist, die verbleibenden Störungen während der Erfahrung zu finden und zu verstehen. Bestehende Methoden aus dem Laborkontext sind entweder nicht präzise genug, z.B. Fragebögen, um diese Störungen zu finden oder verursachen einen hohen Aufwand in ihrer Anwendung und Auswertung, z.B. physilogische Messungen. In einer Literaturübersicht zeigen wir, dass die aktuelle Forschung stark auf fragebogenbasierte Ansätze angewiesen ist. Ich verbessern aktuelle qualitative Ansätze -- Interviews, Fragebögen -- um die zeitliche Variation einer VR-Erfahrung bewertbar zu machen. Ich schlagen eine Zeichnungsmethode vor die Brüche in der Präsenzerfahrung erkennt, den Benutzer bei der Reflexion einer HMD-basierten Erfahrung hilft und die Kommunikation zwischen einem Interviewer und dem HMD-Benutzer unterstützt. In der gleichen Veröffentlichung schlage ich ein Modell vor, das die objektive Beschreibung der zeitlichen Variationen einer Präsenzerfahrung von Anfang bis Ende ermöglicht. Weiterhin präsentieren und erforschen ich das Konzept der Elektroenzephalographie, um den visuellen Stress eines HMD-Anwenders objektiv zu erfassen. Die objektive Erkennung unterstützt den Einsatz von HMDs im privaten und industriellen Kontext, da sie die Gesundheit des Benutzers sicherstellt. Mit meiner Arbeit möchte ich auf die neuen Herausforderungen beim Einsatz von VR-Technologien im Alltag aufmerksam machen. Ich hoffe, dass meine Konzepte, Methoden und Evaluierungswerkzeuge der Forschung und Entwicklung über den Einsatz von HMDs dienen werden. Insbesondere möchte ich den Einsatz im alltäglichen sozialen Kontext fördern und damit eine bereichernde Erfahrung für alle schaffen

The benefits of using a walking interface to navigate virtual environments

Navigation is the most common interactive task performed in three-dimensional virtual environments (VEs), but it is also a task that users often find difficult. We investigated how body-based information about the translational and rotational components of movement helped participants to perform a navigational search task (finding targets hidden inside boxes in a room-sized space). When participants physically walked around the VE while viewing it on a head-mounted display (HMD), they then performed 90% of trials perfectly, comparable to participants who had performed an equivalent task in the real world during a previous study. By contrast, participants performed less than 50% of trials perfectly if they used a tethered HMD (move by physically turning but pressing a button to translate) or a desktop display (no body-based information). This is the most complex navigational task in which a real-world level of performance has been achieved in a VE. Behavioral data indicates that both translational and rotational body-based information are required to accurately update one's position during navigation, and participants who walked tended to avoid obstacles, even though collision detection was not implemented and feedback not provided. A walking interface would bring immediate benefits to a number of VE applications

Designing mobile augmented reality art applications:addressing the views of the galleries and the artists

The utilization of mobile augmented reality to display gallery artworks or museum content in novel ways is a well-established concept in the augmented reality research community. However, the focus of these systems is generally technologically driven or only addresses the end user and not the views of the gallery or the original artist. In this paper we discuss the design and development of the mobile application ?Taking the Artwork Home?, which allows people to digitally curate their own augmented reality art exhibitions in their own homes by digitally ?replacing? the pictures they have on their walls with content from the Peter Scott Gallery in Lancaster. In particular, we present the insights gained from a research through design methodology that allowed us to consider how the views of the gallery and artists impacted on the system design and therefore the user experience. Thus the final artifact is the result of an iterative evaluation process with over 100 users representing a broad range of demographics and continues to be evaluated/enhanced by observing its operation ?in the wild?. Further, we consider the effect the project has had on gallery practices to enable both augmented reality designers, and galleries and museums to maximize the potential application of the technology when working together on such project

Doing augmented reality: a discourse analysis

Since its emergence in the 90s, augmented reality has been referred to as the superimposition of virtual objects on the view of the physical world, and holds a promise to fundamentally change the way we interact with the digital universe. However, AR was never able to achieve such objectives, and after the Google Glass Experiment in 2013, what is evident is a conflict between the research visions and consumer expectations. Seeing that reality is done through discursive practices and enactments, this thesis examines how AR is done by those who are involved in its development, its promotion and its use, through textual and discourse analysis, aiming to understand the vision behind its development. We first analyse the emergence and development of AR, following with the analysis of the Google Glass Experiment, as a materialization of the technology. Taking into consideration the potential for behavior and lifestyle change held in AR development, understanding the underlying discourses and visions is of crucial importance as we bring technology to our reality. As a result we have a better assessment of the current technology situation as well as insights for future development and solutions in the field of augmented reality.Desde o seu surgimento nos anos 90, a realidade aumentada (RA) tem sido referida como a sobreposição de objetos virtuais na visão do mundo físico, e tem consigo a promessa de mudar fundamentalmente a maneira como interagimos com o universo digital. No entanto, a realidade aumentada nunca foi capaz de atingir tais objetivos e, após o Google Glass Experiment em 2013, o que fica evidente é um conflito entre as visões da pesquisa e as expectativas do consumidor. Vendo que a realidade se faz por meio de práticas e decretos discursivos, esta tese examina como a RA é construída por aqueles que estão envolvidos em seu desenvolvimento, sua promoção e seu uso, por meio da análise textual e do discurso, com o objetivo de compreender a visão por trás de seu desenvolvimento. Analisamos primeiro o surgimento e desenvolvimento da RA, seguindo com a análise do Google Glass Experiment, como uma materialização da tecnologia. Levando em consideração o potencial de mudança de comportamento e estilo de vida no desenvolvimento de RA, entender os discursos e visões subjacentes é de importância crucial à medida que trazemos a tecnologia para nossa realidade. Como resultado, temos uma melhor avaliação da situação atual da tecnologia, bem como percepções para o desenvolvimento futuro e soluções no campo da realidade aumentada