8,167 research outputs found

    Communication of Digital Material Appearance Based on Human Perception

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    Im alltägliche Leben begegnen wir digitalen Materialien in einer Vielzahl von Situationen wie beispielsweise bei Computerspielen, Filmen, Reklamewänden in zB U-Bahn Stationen oder beim Online-Kauf von Kleidungen. Während einige dieser Materialien durch digitale Modelle repräsentiert werden, welche das Aussehen einer bestimmten Oberfläche in Abhängigkeit des Materials der Fläche sowie den Beleuchtungsbedingungen beschreiben, basieren andere digitale Darstellungen auf der simplen Verwendung von Fotos der realen Materialien, was zB bei Online-Shopping häufig verwendet wird. Die Verwendung von computer-generierten Materialien ist im Vergleich zu einzelnen Fotos besonders vorteilhaft, da diese realistische Erfahrungen im Rahmen von virtuellen Szenarien, kooperativem Produkt-Design, Marketing während der prototypischen Entwicklungsphase oder der Ausstellung von Möbeln oder Accesoires in spezifischen Umgebungen erlauben. Während mittels aktueller Digitalisierungsmethoden bereits eine beeindruckende Reproduktionsqualität erzielt wird, wird eine hochpräzise photorealistische digitale Reproduktion von Materialien für die große Vielfalt von Materialtypen nicht erreicht. Daher verwenden viele Materialkataloge immer noch Fotos oder sogar physikalische Materialproben um ihre Kollektionen zu repräsentieren. Ein wichtiger Grund für diese Lücke in der Genauigkeit des Aussehens von digitalen zu echten Materialien liegt darin, dass die Zusammenhänge zwischen physikalischen Materialeigenschaften und der vom Menschen wahrgenommenen visuellen Qualität noch weitgehend unbekannt sind. Die im Rahmen dieser Arbeit durchgeführten Untersuchungen adressieren diesen Aspekt. Zu diesem Zweck werden etablierte digitalie Materialmodellen bezüglich ihrer Eignung zur Kommunikation von physikalischen und sujektiven Materialeigenschaften untersucht, wobei Beobachtungen darauf hinweisen, dass ein Teil der fühlbaren/haptischen Informationen wie z.B. Materialstärke oder Härtegrad aufgrund der dem Modell anhaftenden geometrische Abstraktion verloren gehen. Folglich wird im Rahmen der Arbeit das Zusammenspiel der verschiedenen Sinneswahrnehmungen (mit Fokus auf die visuellen und akustischen Modalitäten) untersucht um festzustellen, welche Informationen während des Digitalisierungsprozesses verloren gehen. Es zeigt sich, dass insbesondere akustische Informationen in Kombination mit der visuellen Wahrnehmung die Einschätzung fühlbarer Materialeigenschaften erleichtert. Eines der Defizite bei der Analyse des Aussehens von Materialien ist der Mangel bezüglich sich an der Wahnehmung richtenden Metriken die eine Beantwortung von Fragen wie z.B. "Sind die Materialien A und B sich ähnlicher als die Materialien C und D?" erlauben, wie sie in vielen Anwendungen der Computergrafik auftreten. Daher widmen sich die im Rahmen dieser Arbeit durchgeführten Studien auch dem Vergleich von unterschiedlichen Materialrepräsentationen im Hinblick auf. Zu diesem Zweck wird eine Methodik zur Berechnung der wahrgenommenen paarweisen Ähnlichkeit von Material-Texturen eingeführt, welche auf der Verwendung von Textursyntheseverfahren beruht und sich an der Idee/dem Begriff der geradenoch-wahrnehmbaren Unterschiede orientiert. Der vorgeschlagene Ansatz erlaubt das Überwinden einiger Probleme zuvor veröffentlichter Methoden zur Bestimmung der Änhlichkeit von Texturen und führt zu sinnvollen/plausiblen Distanzen von Materialprobem. Zusammenfassend führen die im Rahmen dieser Dissertation dargestellten Inhalte/Verfahren zu einem tieferen Verständnis bezüglich der menschlichen Wahnehmung von digitalen bzw. realen Materialien über unterschiedliche Sinne, einem besseren Verständnis bzgl. der Bewertung der Ähnlichkeit von Texturen durch die Entwicklung einer neuen perzeptuellen Metrik und liefern grundlegende Einsichten für zukünftige Untersuchungen im Bereich der Perzeption von digitalen Materialien.In daily life, we encounter digital materials and interact with them in numerous situations, for instance when we play computer games, watch a movie, see billboard in the metro station or buy new clothes online. While some of these virtual materials are given by computational models that describe the appearance of a particular surface based on its material and the illumination conditions, some others are presented as simple digital photographs of real materials, as is usually the case for material samples from online retailing stores. The utilization of computer-generated materials entails significant advantages over plain images as they allow realistic experiences in virtual scenarios, cooperative product design, advertising in prototype phase or exhibition of furniture and wearables in specific environments. However, even though exceptional material reproduction quality has been achieved in the domain of computer graphics, current technology is still far away from highly accurate photo-realistic virtual material reproductions for the wide range of existing categories and, for this reason, many material catalogs still use pictures or even physical material samples to illustrate their collections. An important reason for this gap between digital and real material appearance is that the connections between physical material characteristics and the visual quality perceived by humans are far from well-understood. Our investigations intend to shed some light in this direction. Concretely, we explore the ability of state-of-the-art digital material models in communicating physical and subjective material qualities, observing that part of the tactile/haptic information (eg thickness, hardness) is missing due to the geometric abstractions intrinsic to the model. Consequently, in order to account for the information deteriorated during the digitization process, we investigate the interplay between different sensing modalities (vision and hearing) and discover that particular sound cues, in combination with visual information, facilitate the estimation of such tactile material qualities. One of the shortcomings when studying material appearance is the lack of perceptually-derived metrics able to answer questions like "are materials A and B more similar than C and D?", which arise in many computer graphics applications. In the absence of such metrics, our studies compare different appearance models in terms of how capable are they to depict/transmit a collection of meaningful perceptual qualities. To address this problem, we introduce a methodology to compute the perceived pairwise similarity between textures from material samples that makes use of patch-based texture synthesis algorithms and is inspired on the notion of Just-Noticeable Differences. Our technique is able to overcome some of the issues posed by previous texture similarity collection methods and produces meaningful distances between samples. In summary, with the contents presented in this thesis we are able to delve deeply in how humans perceive digital and real materials through different senses, acquire a better understanding of texture similarity by developing a perceptually-based metric and provide a groundwork for further investigations in the perception of digital materials

    Transient Analysis for Music and Moving Images: Consideration for Television Advertising

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    In audiovisual composition, coupling montage moving images with music is common practice. Interpretation of the effect on an audioviewer's consequent interpretation of the composition is discursive and unquantified. Meth-odology for evaluating the audiovisual multimodal inter-activity is proposed, developing an analysis procedure via the study of modality interdependent transient structures, explained as forming the foundation of perception via the concept of Basic Exposure response to the stimulus. The research has implications for analysis of all audiovisual media, with practical implications in television advertis-ing as a discrete typology of target driven audiovisual presentation. Examples from contemporary advertising are used to explore typical transient interaction patterns and the consequences of which are discussed from the practical viewpoint of the audiovisual composer

    Perception of Reverberation in Domestic and Automotive Environments

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    Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 133)

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    This special bibliography lists 276 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System in September 1974

    Crossmodal perception in virtual reality

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    With the proliferation of low-cost, consumer level, head-mounted displays (HMDs) we are witnessing a reappearance of virtual reality. However, there are still important stumbling blocks that hinder the achievable visual quality of the results. Knowledge of human perception in virtual environments can help overcome these limitations. In this work, within the much-studied area of perception in virtual environments, we look into the less explored area of crossmodal perception, that is, the interaction of different senses when perceiving the environment. In particular, we look at the influence of sound on visual perception in a virtual reality scenario. First, we assert the existence of a crossmodal visuo-auditory effect in a VR scenario through two experiments, and find that, similar to what has been reported in conventional displays, our visual perception is affected by auditory stimuli in a VR setup. The crossmodal effect in VR is, however, lower than that present in a conventional display counterpart. Having asserted the effect, a third experiment looks at visuo-auditory crossmodality in the context of material appearance perception. We test different rendering qualities, together with the presence of sound, for a series of materials. The goal of the third experiment is twofold: testing whether known interactions in traditional displays hold in VR, and finding insights that can have practical applications in VR content generation (e.g., by reducing rendering costs)

    Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 156)

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    This bibliography lists 170 reports, articles, and other documents introduced into the NASA scientific and technical information system in June 1976

    Amplifying Actions - Towards Enactive Sound Design

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    Recently, artists and designers have begun to use digital technologies in order to stimulate bodily interaction, while scientists keep revealing new findings about sensorimotor contingencies, changing the way in which we understand human knowledge. However, implicit knowledge generated in artistic projects can become difficult to transfer and scientific research frequently remains isolated due to specific disciplinary languages and methodologies. By mutually enriching holistic creative approaches and highly specific scientific ways of working, this doctoral dissertation aims to set the foundation for Enactive Sound Design. It is focused on sound that engages sensorimotor experience that has been neglected within the existing design practices. The premise is that such a foundation can be best developed if grounded in transdisciplinary methods that bring together scientific and design approaches. The methodology adopted to achieve this goal is practice-based and supported by theoretical research and project analysis. Three different methodologies were formulated and evaluated during this doctoral study, based on a convergence of existing methods from design, psychology and human-computer interaction. First, a basic design approach was used to engage in a reflective creation process and to extend the existing work on interaction gestalt through hands-on activities. Second, psychophysical experiments were carried out and adapted to suit the needed shift from reception-based tests to a performance-based quantitative evaluation. Last, a set of participatory workshops were developed and conducted, within which the enactive sound exercises were iteratively tested through direct and participatory observation, questionnaires and interviews. A foundation for Enactive Sound Design developed in this dissertation includes novel methods that have been generated by extensive explorations into the fertile ground between basic design education, psychophysical experiments and participatory design. Combining creative practices with traditional task analysis further developed this basic design approach. The results were a number of abstract sonic artefacts conceptualised as the experimental apparatuses that can allow psychologists to study enactive sound experience. Furthermore, a collaboration between designers and scientists on a psychophysical study produced a new methodology for the evaluation of sensorimotor performance with tangible sound interfaces.These performance experiments have revealed that sonic feedback can support enactive learning. Finally, participatory workshops resulted in a number of novel methods focused on a holistic perspective fostered through a subjective experience of self-producing sound. They indicated the influence that such an approach may have on both artists and scientists in the future. The role of designer, as a scientific collaborator within psychological research and as a facilitator of participatory workshops, has been evaluated. Thus, this dissertation recommends a number of collaborative methods and strategies that can help designers to understand and reflectively create enactive sound objects. It is hoped that the examples of successful collaborations between designers and scientists presented in this thesis will encourage further projects and connections between different disciplines, with the final goal of creating a more engaging and a more aware sonic future.European Commission 6th Framework and European Science Foundation (COST Action

    THE RELATIONSHIP OF DICHOTIC LISTENING ABILITIES AND SOUND SENSITIVITY FOR OLDER ADULTS

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    ABSTRACT While amplification is the most prevalent treatment for mild to moderately severe hearing loss, many individuals with hearing loss report discomfort with amplified sounds. Despite attempts to resolve these issues with digital sound processing, adverse effects continue to be reported. It is possible these adverse effects are due to sound sensitivity rather than over amplification. Sound sensitivity has been found to relate to personality traits, emotionality, anxiety, depression, and self-reported hearing disability. One way to evaluate sound sensitivities is to explore how individuals accept sound. Sound acceptability is a holistic construct that attempts to evaluate a sound’s aversiveness, pleasantness, annoyance, and other factors. Relationships between personality traits and emotional reactivity and their possible impact on sound acceptability have not been explored. Therefore, a survey study with 53 adults aged 18 to 30 was conducted to evaluate if those with more negative personality traits and emotionality would report less sound acceptability. Results suggested that those with higher negative emotionality and lower agreeableness in their personality reported less acceptability of everyday sounds. The implications of these relationships are discussed. The factors individuals consider when judging sound acceptability have also not been evaluated previously. It was hypothesized that individuals would consider loudness, duration, and pitch to judge sound acceptability. A study using multi-dimensional scaling was completed with 53 adults aged 18 to 30 to further understand the individual perceptions of the acceptability of everyday sounds. Spatial plots of the resulting data suggested that individuals did in fact consider loudness, although the duration component was more complicated to evaluate. Implications of these findings are discussed. Reduced dichotic listening ability also results in adverse listening outcomes. Yet, the relationship between dichotic listening and sound sensitivity has not been explored. It was hypothesized that those with poorer dichotic listening ability would have more sound sensitivity than those with normal dichotic listening abilities. The final study examined this hypothesis in a group of 36 adults aged 65-79 years old through a cross-sectional survey. The survey evaluated measures of personality, emotional reactivity, anxiety/depression, cognitive ability, sound sensitivity, and dichotic listening ability. Relationships between anxiety/depression, dichotic listening, and sound sensitivity were evaluated. There was a significant relationship between poorer dichotic listening and increased sound sensitivity. However, this effect was fully mediated by anxiety/depression, suggesting that those with poorer dichotic listening ability are likely to have higher anxiety/depression, which results in more sound sensitivity. This may affect clinical outcomes with amplification for this population. Implications of these results are discussed
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