Challenges to deliver 2D/3D content for multimedia applications in mobile environments

In the context of multimedia and hypermedia systems, the aspect of including mobile links to a stationary infrastructure and the use of mobile data terminals are gaining increasingly in importance. The current advancements of hardware, software, and telecommunications technology allow multimedia systems to be implemented in mobile environments. Nevertheless, in order to fully reach that goal and to meet the end-users' expectations, specific limitations and usage scenarios of mobile environments have to be taken into consideration. This paper will give a definition of "multimedia" and will describe its major aspects. After presenting these aspects, a scheme for media representation levels is discussed. The main focus in the following parts of the paper is the application of 2D/3D vector graphics and animation for mobile services. The concept of an integrated scene graph and its application in a mobile map service is discussed. The integrated scene graph and its usage as a plugin inside a WWW based browser allows the creation of new, graphics-based services, customized for a mogile platform. The different features introduced by the implementation effort are described, e.g. the overlay and tiling concept, and support for animation on-demand. The plugin is used by the "City Inforamtion Service" which is part or the MOMENTS project (AC002, Mobile Media and ENTertainment Services). Besides the handling of 2D/3D graphics and animation, the plugin allows the specification of different interactions for the mobile user. Besides its use as an enhanced viewer for map material, the plugin concept and its implementaiton can also be adopted for other types of services. For this, different profiles concerning the usage of VRML 2.0, the "Virtual Reality Modeling Language", are taken into consideration. Finally we provide a conclusion and show up direction for future work.