48,962 research outputs found

    Life (low voice or medium voice and piano)

    Get PDF
    In this paper we describe the design and implementation of a multi-purpose object-oriented authoring system for interactive virtual environments and presentations, semi-interactive 3D visualization, and non-interactive photo-realistic animations. Its main design criteria are reusability and flexibility, especially in the support of a wide range of input and output formats. Input data may be provided from any type of event-oriented simulation system as well as from an interactive scene modeling tool. The primary output system is a Java-based VRML browser, but a concept of output driver channels allows the use of other rendering systems, such as off-line renderers for the production of photo-realistic video streams. Objects used in the system consist of both geometry and behavior, where the latter is defined in C++ and/or Java. Objects are provided in different abstraction levels and are stored in an animation element library for reuse in different application scenarios

    Video summarisation: A conceptual framework and survey of the state of the art

    Get PDF
    This is the post-print (final draft post-refereeing) version of the article. Copyright @ 2007 Elsevier Inc.Video summaries provide condensed and succinct representations of the content of a video stream through a combination of still images, video segments, graphical representations and textual descriptors. This paper presents a conceptual framework for video summarisation derived from the research literature and used as a means for surveying the research literature. The framework distinguishes between video summarisation techniques (the methods used to process content from a source video stream to achieve a summarisation of that stream) and video summaries (outputs of video summarisation techniques). Video summarisation techniques are considered within three broad categories: internal (analyse information sourced directly from the video stream), external (analyse information not sourced directly from the video stream) and hybrid (analyse a combination of internal and external information). Video summaries are considered as a function of the type of content they are derived from (object, event, perception or feature based) and the functionality offered to the user for their consumption (interactive or static, personalised or generic). It is argued that video summarisation would benefit from greater incorporation of external information, particularly user based information that is unobtrusively sourced, in order to overcome longstanding challenges such as the semantic gap and providing video summaries that have greater relevance to individual users

    Space time pixels

    Get PDF
    This paper reports the design of a networked system, the aim of which is to provide an intermediate virtual space that will establish a connection and support interaction between multiple participants in two distant physical spaces. The intention of the project is to explore the potential of the digital space to generate original social relationships between people that their current (spatial or social) position can difficultly allow the establishment of innovative connections. Furthermore, to explore if digital space can sustain, in time, low-level connections like these, by balancing between the two contradicting needs of communication and anonymity. The generated intermediate digital space is a dynamic reactive environment where time and space information of two physical places is superimposed to create a complex common ground where interaction can take place. It is a system that provides awareness of activity in a distant space through an abstract mutable virtual environment, which can be perceived in several different ways – varying from a simple dynamic background image to a common public space in the junction of two private spaces or to a fully opened window to the other space – according to the participants will. The thesis is that the creation of an intermediary environment that operates as an activity abstraction filter between several users, and selectively communicates information, could give significance to the ambient data that people unconsciously transmit to others when co-existing. It can therefore generate a new layer of connections and original interactivity patterns; in contrary to a straight-forward direct real video and sound system, that although it is functionally more feasible, it preserves the existing social constraints that limit interaction into predefined patterns

    Inviwo -- A Visualization System with Usage Abstraction Levels

    Full text link
    The complexity of today's visualization applications demands specific visualization systems tailored for the development of these applications. Frequently, such systems utilize levels of abstraction to improve the application development process, for instance by providing a data flow network editor. Unfortunately, these abstractions result in several issues, which need to be circumvented through an abstraction-centered system design. Often, a high level of abstraction hides low level details, which makes it difficult to directly access the underlying computing platform, which would be important to achieve an optimal performance. Therefore, we propose a layer structure developed for modern and sustainable visualization systems allowing developers to interact with all contained abstraction levels. We refer to this interaction capabilities as usage abstraction levels, since we target application developers with various levels of experience. We formulate the requirements for such a system, derive the desired architecture, and present how the concepts have been exemplary realized within the Inviwo visualization system. Furthermore, we address several specific challenges that arise during the realization of such a layered architecture, such as communication between different computing platforms, performance centered encapsulation, as well as layer-independent development by supporting cross layer documentation and debugging capabilities

    Painterly rendering techniques: A state-of-the-art review of current approaches

    Get PDF
    In this publication we will look at the different methods presented over the past few decades which attempt to recreate digital paintings. While previous surveys concentrate on the broader subject of non-photorealistic rendering, the focus of this paper is firmly placed on painterly rendering techniques. We compare different methods used to produce different output painting styles such as abstract, colour pencil, watercolour, oriental, oil and pastel. Whereas some methods demand a high level of interaction using a skilled artist, others require simple parameters provided by a user with little or no artistic experience. Many methods attempt to provide more automation with the use of varying forms of reference data. This reference data can range from still photographs, video, 3D polygonal meshes or even 3D point clouds. The techniques presented here endeavour to provide tools and styles that are not traditionally available to an artist. Copyright © 2012 John Wiley & Sons, Ltd

    Building self-optimized communication systems based on applicative cross-layer information

    Get PDF
    This article proposes the Implicit Packet Meta Header(IPMH) as a standard method to compute and represent common QoS properties of the Application Data Units (ADU) of multimedia streams using legacy and proprietary streams’ headers (e.g. Real-time Transport Protocol headers). The use of IPMH by mechanisms located at different layers of the communication architecture will allow implementing fine per-packet selfoptimization of communication services regarding the actual application requirements. A case study showing how IPMH is used by error control mechanisms in the context of wireless networks is presented in order to demonstrate the feasibility and advantages of this approach
    corecore