Contextual information in virtual collaboration systems beyond current standards

Abstract

Context-aware applications are fast becoming popular as a means of enriching users' experiences in various multimedia content access and delivery scenarios. Nevertheless, the definition, identification, and representation of contextual information are still open issues that need to be addressed. In this paper, we briefly present our work developed within the VISNET II Network of Excellence (NoE) project on context-based content adaptation in Virtual Collaboration Systems (VCSs). Based on the conducted research, we conclude that MPEG-21 Digital Item Adaptation (DIA) is the most complete standardization initiative to represent context for content adaptation. However, tools defined in MPEG-21 DIA Usage Environment Descriptors (UEDs) are not adequate for Virtual Collaboration application scenarios, and thus, we propose potential extensions to the available UEDs.

Advanced delivery of sensitive multimedia content for better serving user expectations in Virtual Collaboration applications

“…These features are briefly explained in Section 3. Details can be found in previous publications and Web repository [3]- [5].…”

“…Although kept simple, our ontology is easily extendable and it is powerful as it already supports security aspects, as well as new types of contextual information. Such is the case of the "hasFloor" descriptor, useful for VC applications, which is further detailed in Section 4 and in [4].…”

“…The proposed AES has been organized in a 3-layer architecture as represented in Figure 4. This layered architecture is detailed in [3]- [5]. Table I has listed the major types of adaptation operations offered by the AES, which is envisaged to reduce the processing latency for performing multiple adaptation operations in a sequence.…”

“…Implementation of these licenses, based on MPEG-21 REL and DIA [27], has been described in [3]- [5]. The use of these licenses brings innovation to the AA in two dimensions: on one hand, fine-grained descriptions about adaptations expressed in MPEG-21 DIA allow governing these adaptation operations in a flexible way; on the other hand, the use of MPEG-21 REL guarantees the reliability of the system and its interoperability with other DRM standards.…”

“…However, interested readers are kindly invited to find further in-depth information in previous publications [3]- [5]. As referred above, the main goal of this paper is to describe the use and benefits of the platform under real-world situations, providing a detailed and quantitative characterization of contextual conditions that would affect the quality of experience of the user.…”