Showing papers by "Christian Timmerer published in 2004"

Evaluation of models for parsing binary encoded XML-based metadata

Abstract: In multimedia applications, XML is being increasingly used to represent metadata As with the media data, the size of, or the overhead induced by, the XML metadata is important, particularly when used on constrained mobile devices Therefore, compression (binary encoding) of the XML data becomes relevant to reduce this overhead Within the MPEG-7 standardization effort, a binary format for metadata (BiM) was developed, providing good compression efficiency and facilitating random access into, and manipulation of, the binary encoded bit stream In order to support processing of metadata streams in the binary domain and making this task for client applications as simple as possible, we are developing a universal parser for handling both plain text and binary encoded XML-based metadata The parser exposes a single interface making it transparent for the application whether a plain text or a binary XML document is being processed As part of this effort, this paper provides a detailed study of five existing XML parser models and evaluates their applicability to serve as a model for parsing binary XML data

Toward Semantic Web Services for Multimedia Adaptation

Abstract: Universal Multimedia Access (UMA), where users can consume any multimedia resource anywhere at any time, is the driving vision of ongoing ISO/IEC Moving Picture Experts Group (MPEG) standardization efforts. In that context, intelligent adaptation means that before resources are sent over the network, they are prepared according to the client’s device capabilities, the network conditions, or even the user’s content preferences. In this paper, we argue that Semantic Web Services can serve as a key enabling technology to achieve the goals of UMA. As the standards evolve, more and more specialized software tools will be available that provide specific functionalities for adapting the media in different dimensions. When the functionality of such tools is described declaratively with the means of Semantic Web Services technology, intelligent adaptation network nodes can be developed, capable of automatically composing multi-step adaptation sequences and dynamically integrating such services available on the Web. This paper describes the architecture and a prototypical implementation of an intelligent adaptation node that supports automatic, knowledge-based service composition which is made possible by the shared domain ontology defined in MPEG metadata standards.

Interoperable multimediale Kommunikation im Internet mittels MPEG-21 Digital Item Adaptation

Abstract: Digital Item Adaptation (DIA) ist der jungste Standard im Rahmen des ISO/IEC MPEG-21 Multimedia Frameworks. Dieser Standard spezifiziert Deskriptoren und Konzepte (Tools) fur die interoperable Kommunikation und ggf. Adaption von komplexen digitalen multimedialen Objekten, sog. Digital Items. Schwierigkeiten der Kommunikation und ggf. die Notwendigkeit der Adaption multimedialer Inhalte entstehen durch die Heterogenitat und Beschrankungen der durchlaufenen Netze (z.B. im heutigen Internet) und der benutzten Endgerate sowie durch unterschiedliche Praferenzen und Profile der Nutzer. Dieser Artikel beschreibt eine endgerateund codierformat-unabhangige Komponente zur Adaption von Digital Items an verschiedene (mobile) Endgerate und Netzcharakteristika.