Saar De Zutter

MPEG-21 digital item Processing

This paper introduces the concept of MPEG-21 Digital Item Processing (DIP), which enables the incorporation of interoperable descriptions of programmability related to the multimedia experience. In the first part of the paper, a motivation for defining DIP is outlined and the different terms and definitions used within DIP are defined and discussed. The second part of the paper gives an overview of the current development status of DIP and discusses the Application Programming Interfaces provided to the Digital Item Method author. This illustrates how DIP can be used to interact between the different parts of MPEG-21. A walkthrough of the DIP process is given enabling the creation of a truly interoperable MPEG-21 DIP peer. Finally, the paper ends with some conclusions and gives some insight on what can be expected for DIP in the future.

System architecture for semantic annotation and adaptation in content sharing environments

This paper describes a system architecture, which enables the automatic semantic annotation and adaptation of multimedia content in context-aware content sharing environments. The discussed architecture is the result of research done in the EU FP6 IST INTERMEDIA project. Generating a common vision on user-centric multimedia services in shared content environments to provide users with content personalized to their user preferences and usage environment is one of the objectives of the project. The work presented in this paper describes how media formats with their related metadata are automatically annotated and dynamically adapted. Based on the architecture, a full-featured demonstrator is built.

Ambient-aware continuous care through semantic context dissemination

BackgroundThe ultimate ambient-intelligent care room contains numerous sensors and devices to monitor the patient, sense and adjust the environment and support the staff. This sensor-based approach results in a large amount of data, which can be processed by current and future applications, e.g., task management and alerting systems. Today, nurses are responsible for coordinating all these applications and supplied information, which reduces the added value and slows down the adoption rate.The aim of the presented research is the design of a pervasive and scalable framework that is able to optimize continuous care processes by intelligently reasoning on the large amount of heterogeneous care data.MethodsThe developed Ontology-based Care Platform (OCarePlatform) consists of modular components that perform a specific reasoning task. Consequently, they can easily be replicated and distributed. Complex reasoning is achieved by combining the results of different components. To ensure that the components only receive information, which is of interest to them at that time, they are able to dynamically generate and register filter rules with a Semantic Communication Bus (SCB). This SCB semantically filters all the heterogeneous care data according to the registered rules by using a continuous care ontology. The SCB can be distributed and a cache can be employed to ensure scalability.ResultsA prototype implementation is presented consisting of a new-generation nurse call system supported by a localization and a home automation component. The amount of data that is filtered and the performance of the SCB are evaluated by testing the prototype in a living lab. The delay introduced by processing the filter rules is negligible when 10 or fewer rules are registered.ConclusionsThe OCarePlatform allows disseminating relevant care data for the different applications and additionally supports composing complex applications from a set of smaller independent components. This way, the platform significantly reduces the amount of information that needs to be processed by the nurses. The delay resulting from processing the filter rules is linear in the amount of rules. Distributed deployment of the SCB and using a cache allows further improvement of these performance results.

Performance analysis of MPEG-21 technologies on mobile devices

This paper gives an introduction to technologies and methodologies to measure performance of MPEG-21 applications in mobile environments. Since resources, such as processing time, available memory, storage, network, and battery time, are very sparse on mobile devices, it is important to optimize technologies to use as little as possible of those resources. To identify possible optimization points for MPEG-21 technologies, performance measurements technologies are applied on a prototype implementation of MPEG-21 Digital Item Declaration and Digital Item Processing. The upcoming MPEG-21 its goal is providing transparent and augmented use of multimedia resources across a plethora of networks and devices. The prototype, which has been implemented on the J2ME platform, gives information about possible bottlenecks when designing MPEG-21 based applications. The results of the measurements are discussed and used to identify which improvements need to be realized to reduce memory and processor consumption when implementing the discussed parts of the MPEG-21 standards on a mobile platform. This paper ends with a discussion and concluding remarks.

Efficient context management in context-aware environments

Environments in which multimedia applications are used become more complex and gain importance. Users expect applications to be customized to their needs and tailored to their usage environment. Therefore, on the one hand, context environment information needs to be managed in an efficient manner to optimize usage of this valuable information. On the other hand, to improve the collection of this pervasive context information, information required for services in the environment needs to be accounted for. Different technologies exist to describe the usage environment and the interaction with this description environment. In order to optimize management of all this information, our developed efficient context management service links context providers to context consumers and takes into account prior knowledge about these providers and consumers to make decisions. Efficiency of other multimedia services such as context collection and content adaptation services can be enhanced when the discussed methodology is applied.

Predictable processing of multimedia content, using MPEG-21 digital item processing

Within an MPEG-21 architecture, the two key concepts are the Digital Item, representing multimedia content, and Users, interacting with this content. MPEG-21 introduced Digital Item Processing to allow content authors to describe suggested processing of their Digital Items. It standardizes ways to insert functionality into a Digital Item, as such, creating a dynamic and interactive multimedia format. Moreover, if a terminal wants to support Digital Item Processing, it needs to provide an execution environment offering basic functionality. The semantics of this functionality have been standardized, however there is significant room for interpretation. Consequently, a Digital Item author may not be aware of the actual processing when using this functionality. In this paper, a system is proposed, compliant with the Digital Item Processing specification, to give content creators full control on the processing. This allows creating advanced predictable multimedia systems in an MPEG- 21 environment.