Measuring the Discernability of Virtual Objects in Conventional and Stylized Augmented Reality

In augmented reality, virtual graphical objects are overlaid over the real environment of the observer. Conventional augmented reality systems normally use standard real-time rendering methods for generating the graphical representations of virtual objects. These renderings contain the typical artifacts of computer generated graphics, e.g., aliasing caused by the rasterization process and unrealistic, manually configured illumination models. Due to these artifacts, virtual objects look artifical and can easily be distinguished from the real environment. A different approach to generating augmented reality images is the basis of stylized augmented reality [FBS05c]. Here, similar types of artistic or illustrative stylization are applied to the virtual objects and the camera image of the real enviroment. Therefore, real and virtual image elements look significantly more similar and are less distinguishable from each other. In this paper, we present the results of a psychophysical study on the effectiveness of stylized augmented reality. In this study, a number of participants were asked to decide whether objects shown in images of augmented reality scenes are virtual or real. Conventionally rendered as well as stylized augmented reality images and short video clips were presented to the participants. The correctness of the participants' responses and their reaction times were recorded. The results of our study show that an equalized level of realism is achieved by using stylized augmented reality, i.e., that it is significantly more difficult to distinguish virtual objects from real objects

Handling photographic imperfections and aliasing in augmented reality

In video see-through augmented reality, virtual objects are overlaid over images delivered by a digital video camera. One particular problem of this image mixing process is the fact that the visual appearance of the computer-generated graphics differs strongly from the real background image. In typical augmented reality systems, standard real-time rendering techniques are used for displaying virtual objects. These fast, but relatively simplistic methods create an artificial, almost "plastic-like" look for the graphical elements. In this paper, methods for incorporating two particular camera image effects in virtual overlays are described. The first effect is camera image noise, which is contained in the data delivered by the CCD chip used for capturing the real scene. The second effect is motion blur, which is caused by the temporal integration of color intensities on the CCD chip during fast movements of the camera or observed objects, resulting in a blurred camera image. Graphical objects rendered with standard methods neither contain image noise nor motion blur. This is one of the factors which makes the virtual objects stand out from the camera image and contributes to the perceptual difference between real and virtual scene elements. Here, approaches for mimicking both camera image noise and motion blur in the graphical representation of virtual objects are proposed. An algorithm for generating a realistic imitation of image noise based on a camera calibration step is described. A rendering method which produces motion blur according to the current camera movement is presented. As a by-product of the described rendering pipeline, it becomes possible to perform a smooth blending between virtual objects and the camera image at their boundary. An implementation of the new rendering methods for virtual objects is described, which utilizes the programmability of modern graphics processing units (GPUs) and is capable of delivering real-time frame rates

Fidelity and plausibility of bimanual interaction in mixed reality

When human actors interact with virtual objects the result is often not convincing to a third party viewer, due to incongruities between the actor and object positions. In this study we aim to quantify the magnitude and impact of the errors that occur in a bimanual interaction, that is when an actor attempts to move a virtual object by holding it between both hands. A three stage framework is presented which firstly captures the magnitude of these interaction errors, then quantifies their effect on the relevant third party audience, and thirdly assesses methods to mitigate the impact of the errors. Findings from this work show that the degree of error was dependent on the size of the virtual object and also on the axis of the hand placement with respect to the axis of the interactive motion. In addition, actor hand placement outside and away from the object surface was found to affect the visual plausibility considerably more than when the actor's hands were within the object boundaries. Finally, a method for automatic adaptation of the object size to match the distance between the actor's hands gave a significant improvement in the viewers' assessment of the scene plausibility. © 1995-2012 IEEE

Augmented Reality, Virtual Reality and their effect on learning style in the creative design process

Research has shown that user characteristics such as preference for using an interface can result in effective use of the interface. Research has also suggested that there is a relationship between learner preference and creativity. This study uses the VARK learning styles inventory to assess students learning style then explores how this learning preference affect the use of Augmented Reality (AR) and Virtual Reality (VR) in the creative design process

Video Manipulation Techniques for the Protection of Privacy in Remote Presence Systems

Systems that give control of a mobile robot to a remote user raise privacy concerns about what the remote user can see and do through the robot. We aim to preserve some of that privacy by manipulating the video data that the remote user sees. Through two user studies, we explore the effectiveness of different video manipulation techniques at providing different types of privacy. We simultaneously examine task performance in the presence of privacy protection. In the first study, participants were asked to watch a video captured by a robot exploring an office environment and to complete a series of observational tasks under differing video manipulation conditions. Our results show that using manipulations of the video stream can lead to fewer privacy violations for different privacy types. Through a second user study, it was demonstrated that these privacy-protecting techniques were effective without diminishing the task performance of the remote user.Comment: 14 pages, 8 figure

Towards achieving convincing live interaction in a mixed reality environment for television studios

The virtual studio is a form of Mixed Reality environment for creating television programmes, where the (real) actor appears to exist within an entirely virtual set. The work presented in this thesis evaluates the routes required towards developing a virtual studio that extends from current architectures in allowing realistic interactions between the actor and the virtual set in real-time. The methodologies and framework presented in this thesis is intended to support future work in this domain. Heuristic investigation is offered as a framework to analyse and provide the requirements for developing interaction within a virtual studio. In this framework a group of experts participate in case study scenarios to generate a list of requirements that guide future development of the technology. It is also concluded that this method could be used in a cyclical manner to further refine systems postdevelopment. This leads to the development of three key areas. Firstly a feedback system is presented, which tracks actor head motion within the studio and provides dynamic visual feedback relative to their current gaze location. Secondly a real-time actor/virtual set occlusion system that uses skeletal tracking data and depth information to change the relative location of virtual set elements dynamically is developed. Finally an interaction system is presented that facilitates real-time interaction between an actor and the virtual set objects, providing both single handed and bimanual interactions. Evaluation of this system highlights some common errors in mixed reality interaction, notably those arising from inaccurate hand placement when actors perform bimanual interactions. A novel two stage framework is presented that measures the magnitude of the errors in actor hand placement, and also, the perceived fidelity of the interaction from a third person viewer. The first stage of this framework quantifies the actor motion errors while completing a series of interaction tasks under varying controls. The second stage uses examples of these errors to measure the perceptual tolerance of a third person when viewing interaction errors in the end broadcast. The results from this two stage evaluation lead to the development of three methods for mitigating the actor errors, with each evaluated against its ability to aid in the visual fidelity of the interaction. It was discovered that the adapting the size of the virtual object was effective in improving the quality of the interaction, whereas adapting the colour of any exposed background did not have any apparent effects. Finally a set of guidelines based on these findings is provided to recommend appropriate solutions that can be applied for allowing interaction within live virtual studio environments that can easily be adapted for other mixed reality systems

Avaliação de usabilidade de ambientes de realidade virtual e aumentada

Mestrado em Gestão da informaçãoEsta dissertação tem como principal objectivo verificar a possibilidade da utilização de métodos e técnicas de avaliação de usabilidade criados para ambientes 2D em ambientes de realidade virtual e aumentada. Para alcançar tal objectivo foi realizada uma revisão bibliográfica dos principais conceitos e características dos ambientes de realidade virtual e aumentada, dos princípios e paradigmas que regem a usabilidade e das principais formas de avaliação da mesma. Com base no levantamento bibliográfico foram desenvolvidas duas experiências: a primeira consistiu numa experiência controlada com o objectivo de comparar o desempenho dos utilizadores num jogo desenvolvido num ambiente de realidade virtual e num ambiente desktop. A segunda permitiu uma avaliação qualitativa que se baseou na opinião de vários utilizadores depois dos mesmos visualizarem dados das suas áreas de aplicação num ambiente de realidade aumentada e num desktop. Também foram observadas as diferenças entre as formas de visualização, manipulação e orientação nos vários ambientes utilizados. Apesar das características específicas que os ambientes de realidade virtual e aumentada possuem, tais como manipulação intuitiva, interacção natural, visualização em mais de duas dimensões e utilização de diferentes dispositivos de entrada e saída, uma das principais conclusões desta dissertação é a confirmação da possibilidade de utilização dos métodos gerais de avaliação de usabilidade 2D em ambientes de realidade virtual e aumentada. ABSTRACT: The main objective of this work is to verify the possibility to apply usability evaluation methods and techniques created for 2D environments in virtual and augmented reality. To achieve this objective, a bibliographic review was made to identify the main concepts and characteristics of virtual and augmented reality, the usability paradigms and principles and the typical usability evaluation methods. Based on this review, two different studies were performed: the first one consisted in a controlled experiment meant to compare users’ performances in a gaming scenario in a virtual reality environment and a desktop. The second study was qualitative and some feedback was obtained from domain experts who used an augmented reality set-up as well as a desktop in different data visualization scenarios. During these studies, the differences between the visualization, manipulation and orientation in both environments were also observed. Despite the specific characteristics of virtual and augmented reality environments, such as intuitive manipulation, natural interaction, visualization in more than two dimensions and use of several input and output devices, the overall conclusion is that it is possible to adapt and to use the usability evaluation methods developed for 2D in virtual and augmented reality environments

Privacy-Sensitive Robotics

This dissertation focuses on personal privacy in human-robot interaction, which we call "privacy-sensitive robotics." Our understanding of "privacy" is very broad, including not just information privacy but also physical, psychological, and social privacy. We begin by surveying the scholarly literature on privacy and talking about why it applies to interactions with robots. We then make five contributions to help launch privacy-sensitive robotics as an emerging area of research --- one from a literature review, three from empirical studies, and one about the future of privacy-sensitive robotics research: 1. We begin by presenting the current state of the art in privacy protection technologies (whether or not they were designed as such) from the literature. 2. Our first study found differences in usability and user preference between three different interfaces for specifying user privacy preferences to a robot. 3. Our next study showed how the contextual "framing" of an action affects whether people see it as a privacy violation. 4. Our third and final study documents the process of forming beliefs about the robot's sensing capabilities and identifies some key aspects of this process for further study. 5. Finally, we give a set of recommendations for developing privacy-sensitive robotics as a research area. These five contributions are linked by the goal of privacy-sensitive robotics research: to enable a future in which robotics technology upholds and respects our privacy. We close with a call to action for potential privacy-sensitive robotics researchers

Speed and becoming in the urban public sphere

Concerns about speed and politics focus on the loss of the self-present political subject, whose critical will can direct and legitimate political discourse. The hope of sustaining such a subject is understood to be threatened by the erosion of the ideal-normative grounds that are said to support critical subjectivity (e.g. the city, the community, public space). While the concerns about the character and control of public space are certainly to be taken seriously, it is not clear why we should attach these concerns to a loss of a critical political subjectivity and an erosion of public debate. The argument here begins by acknowledging that speed is an ambivalent quality in politics, both creating a potential to open debate to new identities, and posing the risk that oppositional politics will stall in hard oppositions, or in a failure to recognize that which is truly novel in an event. Both of these risks require that recognized identities begin to 'leak', and become open to a world whose potential exceeds the recognized permutations of the possible. This thesis explores how a public, and its implied subjectivities, are maintained 'at speed', within the multiple timespaces of the contemporary city. Instead of an objective speed that comes from without, and overwhelms the subject, time is conceptualized as duration; an immanent view of time in which speed is characterized as repeated disruptions. A public can form around these repeated disruptions. The public is understood to be an assemblage, in Deleuze and Guattari's use of the term, which is sustained by the circulation of texts. A public actualizes wherever, and whenever, there is a successful conjunction of text and context. These conjunctions are not determined, but are only determinable in the event of their actualization. However, it is possible to create a diagram of the assemblage which highlights the potential that exists for the formation of a public, as well as the potential to go beyond recognized subjectivities and open the assemblage to a process of becoming. This thesis creates such a diagram for the smog-event in Toronto, Canada, and engages in an 'experimental critique'. An experimental critique seeks to explore how the event has been placed into circulation in the public sphere, and to encourage experimentation with the limits of recognised identities and possibilities that are sustained in the public assemblage