21 research outputs found

    Synchronized Illumination Modulation for Digital Video Compositing

    Get PDF
    Informationsaustausch ist eines der Grundbedürfnisse der Menschen. Während früher dazu Wandmalereien,Handschrift, Buchdruck und Malerei eingesetzt wurden, begann man später, Bildfolgen zu erstellen, die als sogenanntes ”Daumenkino” den Eindruck einer Animation vermitteln. Diese wurden schnell durch den Einsatz rotierender Bildscheiben, auf denen mit Hilfe von Schlitzblenden, Spiegeln oder Optiken eine Animation sichtbar wurde, automatisiert – mit sogenannten Phenakistiskopen,Zoetropen oder Praxinoskopen. Mit der Erfindung der Fotografie begannen in der zweiten Hälfte des 19. Jahrhunderts die ersten Wissenschaftler wie Eadweard Muybridge, Etienne-Jules Marey und Ottomar Anschütz, Serienbildaufnahmen zu erstellen und diese dann in schneller Abfolge, als Film, abzuspielen. Mit dem Beginn der Filmproduktion wurden auch die ersten Versuche unternommen, mit Hilfe dieser neuen Technik spezielle visuelle Effekte zu generieren, um damit die Immersion der Bewegtbildproduktionen weiter zu erhöhen. Während diese Effekte in der analogen Phase der Filmproduktion bis in die achtziger Jahre des 20.Jahrhunderts recht beschränkt und sehr aufwendig mit einem enormen manuellen Arbeitsaufwand erzeugt werden mussten, gewannen sie mit der sich rapide beschleunigenden Entwicklung der Halbleitertechnologie und der daraus resultierenden vereinfachten digitalen Bearbeitung immer mehr an Bedeutung. Die enormen Möglichkeiten, die mit der verlustlosen Nachbearbeitung in Kombination mit fotorealistischen, dreidimensionalen Renderings entstanden, führten dazu, dass nahezu alle heute produzierten Filme eine Vielfalt an digitalen Videokompositionseffekten beinhalten. ...Besides home entertainment and business presentations, video projectors are powerful tools for modulating images spatially as well as temporally. The re-evolving need for stereoscopic displays increases the demand for low-latency projectors and recent advances in LED technology also offer high modulation frequencies. Combining such high-frequency illumination modules with synchronized, fast cameras, makes it possible to develop specialized high-speed illumination systems for visual effects production. In this thesis we present different systems for using spatially as well as temporally modulated illumination in combination with a synchronized camera to simplify the requirements of standard digital video composition techniques for film and television productions and to offer new possibilities for visual effects generation. After an overview of the basic terminology and a summary of related methods, we discuss and give examples of how modulated light can be applied to a scene recording context to enable a variety of effects which cannot be realized using standard methods, such as virtual studio technology or chroma keying. We propose using high-frequency, synchronized illumination which, in addition to providing illumination, is modulated in terms of intensity and wavelength to encode technical information for visual effects generation. This is carried out in such a way that the technical components do not influence the final composite and are also not visible to observers on the film set. Using this approach we present a real-time flash keying system for the generation of perspectively correct augmented composites by projecting imperceptible markers for optical camera tracking. Furthermore, we present a system which enables the generation of various digital video compositing effects outside of completely controlled studio environments, such as virtual studios. A third temporal keying system is presented that aims to overcome the constraints of traditional chroma keying in terms of color spill and color dependency. ..

    SPATIO-TEMPORAL REGISTRATION IN AUGMENTED REALITY

    Get PDF
    The overarching goal of Augmented Reality (AR) is to provide users with the illusion that virtual and real objects coexist indistinguishably in the same space. An effective persistent illusion requires accurate registration between the real and the virtual objects, registration that is spatially and temporally coherent. However, visible misregistration can be caused by many inherent error sources, such as errors in calibration, tracking, and modeling, and system delay. This dissertation focuses on new methods that could be considered part of "the last mile" of spatio-temporal registration in AR: closed-loop spatial registration and low-latency temporal registration: 1. For spatial registration, the primary insight is that calibration, tracking and modeling are means to an end---the ultimate goal is registration. In this spirit I present a novel pixel-wise closed-loop registration approach that can automatically minimize registration errors using a reference model comprised of the real scene model and the desired virtual augmentations. Registration errors are minimized in both global world space via camera pose refinement, and local screen space via pixel-wise adjustments. This approach is presented in the context of Video See-Through AR (VST-AR) and projector-based Spatial AR (SAR), where registration results are measurable using a commodity color camera. 2. For temporal registration, the primary insight is that the real-virtual relationships are evolving throughout the tracking, rendering, scanout, and display steps, and registration can be improved by leveraging fine-grained processing and display mechanisms. In this spirit I introduce a general end-to-end system pipeline with low latency, and propose an algorithm for minimizing latency in displays (DLP DMD projectors in particular). This approach is presented in the context of Optical See-Through AR (OST-AR), where system delay is the most detrimental source of error. I also discuss future steps that may further improve spatio-temporal registration. Particularly, I discuss possibilities for using custom virtual or physical-virtual fiducials for closed-loop registration in SAR. The custom fiducials can be designed to elicit desirable optical signals that directly indicate any error in the relative pose between the physical and projected virtual objects.Doctor of Philosoph

    MediaSync: Handbook on Multimedia Synchronization

    Get PDF
    This book provides an approachable overview of the most recent advances in the fascinating field of media synchronization (mediasync), gathering contributions from the most representative and influential experts. Understanding the challenges of this field in the current multi-sensory, multi-device, and multi-protocol world is not an easy task. The book revisits the foundations of mediasync, including theoretical frameworks and models, highlights ongoing research efforts, like hybrid broadband broadcast (HBB) delivery and users' perception modeling (i.e., Quality of Experience or QoE), and paves the way for the future (e.g., towards the deployment of multi-sensory and ultra-realistic experiences). Although many advances around mediasync have been devised and deployed, this area of research is getting renewed attention to overcome remaining challenges in the next-generation (heterogeneous and ubiquitous) media ecosystem. Given the significant advances in this research area, its current relevance and the multiple disciplines it involves, the availability of a reference book on mediasync becomes necessary. This book fills the gap in this context. In particular, it addresses key aspects and reviews the most relevant contributions within the mediasync research space, from different perspectives. Mediasync: Handbook on Multimedia Synchronization is the perfect companion for scholars and practitioners that want to acquire strong knowledge about this research area, and also approach the challenges behind ensuring the best mediated experiences, by providing the adequate synchronization between the media elements that constitute these experiences

    Visual Cortex

    Get PDF
    The neurosciences have experienced tremendous and wonderful progress in many areas, and the spectrum encompassing the neurosciences is expansive. Suffice it to mention a few classical fields: electrophysiology, genetics, physics, computer sciences, and more recently, social and marketing neurosciences. Of course, this large growth resulted in the production of many books. Perhaps the visual system and the visual cortex were in the vanguard because most animals do not produce their own light and offer thus the invaluable advantage of allowing investigators to conduct experiments in full control of the stimulus. In addition, the fascinating evolution of scientific techniques, the immense productivity of recent research, and the ensuing literature make it virtually impossible to publish in a single volume all worthwhile work accomplished throughout the scientific world. The days when a single individual, as Diderot, could undertake the production of an encyclopedia are gone forever. Indeed most approaches to studying the nervous system are valid and neuroscientists produce an almost astronomical number of interesting data accompanied by extremely worthy hypotheses which in turn generate new ventures in search of brain functions. Yet, it is fully justified to make an encore and to publish a book dedicated to visual cortex and beyond. Many reasons validate a book assembling chapters written by active researchers. Each has the opportunity to bind together data and explore original ideas whose fate will not fall into the hands of uncompromising reviewers of traditional journals. This book focuses on the cerebral cortex with a large emphasis on vision. Yet it offers the reader diverse approaches employed to investigate the brain, for instance, computer simulation, cellular responses, or rivalry between various targets and goal directed actions. This volume thus covers a large spectrum of research even though it is impossible to include all topics in the extremely diverse field of neurosciences

    Psychological Engagement in Choice and Judgment Under Risk and Uncertainty

    Get PDF
    Theories of choice and judgment assume that agents behave rationally, choose the higher expected value option, and evaluate the choice consistently (Expected Utility Theory, Von Neumann, & Morgenstern, 1947). However, researchers in decision-making showed that human behaviour is different in choice and judgement tasks (Slovic & Lichtenstein, 1968; 1971; 1973). In this research, we propose that psychological engagement and control deprivation predict behavioural inconsistencies and utilitarian performance with judgment and choice. Moreover, we explore the influences of engagement and control deprivation on agent’s behaviours, while manipulating content of utility (Kusev et al., 2011, Hertwig & Gigerenzer 1999, Tversky & Khaneman, 1996) and decision reward (Kusev et al, 2013, Shafir et al., 2002)

    Chi-Thinking: Chiasmus and Cognition

    Get PDF
    The treatise proposes chiasmus is a dominant instrument that conducts processes and products of human thought. The proposition grows out of work in cognitive semantics and cognitive rhetoric. These disciplines establish that conceptualization traces to embodied image schematic knowledge. The Introduction sets out how this knowledge gathers from perceptions, experiences, and memories of the body's commonplace engagements in space. With these ideas as suppositional foundation, the treatise contends that chiastic instrumentation is a function of a corporeal mind steeped in elementary, nonverbal spatial forms or gestalts. It shows that chiasmus is a space shape that lends itself to cognition via its simple, but unique architecture and critically that architecture's particular meaning affordances. We profile some chiastic meanings over others based on local conditions. Chiastic iconicity ('lending') devolves from LINE CROSSING in 2-D and PATH CROSSING in 3-D space and from other image schemas (e.g., BALANCE, PART-TO-WHOLE) that naturally syndicate with CROSSING. Profiling and iconicity are cognitive activities. The spatio-physical and the visual aspects of cross diagonalization are discussed under the Chapter Two heading 'X-ness.' Prior to this technical discussion, Chapter One surveys the exceptional versatility and universality of chiasmus across verbal spectra, from radio and television advertisements to the literary arts. The purposes of this opening section are to establish that chiasticity merits more that its customary status as mere rhetorical figure or dispensable stylistic device and to give a foretaste of the complexity, yet automaticity of chi-thinking. The treatise's first half describes the complexity, diversity, and structural inheritance of chiasmus. The second half treats individual chiasma, everything from the most mundane instantiations to the sublime and virtuosic. Chapter Three details the cognitive dimensions of the macro chiasm, which are appreciable in the micro. It builds on the argument that chiasmus secures two cognitive essentials: association and dissociation. Chapter Four, advantaged by Kenneth Burke's "psychology of form," elects chiasmus an instrument of inordinate form and then explores the issue of Betweenity, i.e., how chiasma, like crisscrosses, direct notice to an intermediate region. The study ends on the premise that chiasmus executes form-meaning pairings with which humans are highly fluent

    NOTIFICATION !!!

    Get PDF
    All the content of this special edition is retrieved from the conference proceedings published by the European Scientific Institute, ESI. http://eujournal.org/index.php/esj/pages/view/books The European Scientific Journal, ESJ, after approval from the publisher re publishes the papers in a Special edition

    NOTIFICATION!!!

    Get PDF
    The full content of this special edition is retrieved from the conference proceedings published by the European Scientific Institute, ESI. http://eujournal.org/index.php/esj/pages/view/books The European Scientific Journal, ESJ, after approval from the publisher re publishes the papers in a Special edition

    NOTIFICATION !!!

    Get PDF
    All the content of this special edition is retrieved from the conference proceedings published by the European Scientific Institute, ESI. http://eujournal.org/index.php/esj/pages/view/books The European Scientific Journal, ESJ, after approval from the publisher re publishes the papers in a Special edition

    NOTIFICATION !!!

    Get PDF
    All the content of this special edition is retrieved from the conference proceedings published by the European Scientific Institute, ESI. http://eujournal.org/index.php/esj/pages/view/books The European Scientific Journal, ESJ, after approval from the publisher re publishes the papers in a Special edition
    corecore