A Synchronization Model for Presentation of Multimedia Objects

To support the presentation requirements of distributed multimedia information, synchronization of multimedia objects must be achieved. To this end, system resource scheduling and resource reservation for object pre-fetch, network bandwidth and buffer occupancy must be determined prior to the time the presentation is initiated. This paper proposes an object-oriented model to handle the temporal relationship for all of the multimedia objects at the presentation platform and study the related problems of resource allocation. Synchronization of the composite media objects is achieved by ensuring that all objects presented in the upcoming “manageable” period must be ready for execution. To this end, the nature of overlap is first examined for various types of objects. The importance of critical overlap and critical point that are vital to synchronization is addressed and taken into account in this research. The concept of manageable presentation interval and the irreducible media group are also introduced and defined. Analysis of resource allocation among pre-fetch time of media object, network bandwidth and buffer occupancy is also examined. Accordingly, a new model called group cascade object composition Petri-net (GCOCPN) is proposed and an algorithm to implement this temporal synchronization scheme is presented.