A framework for distributed multimedia collaborations

Designing a collaborative system which uses multimedia data introduces many new challenges: collaborative systems are distributed, and, furthermore, often they are heterogeneous. Collaborators may have different needs, preferences, and authorization levels; they may have different hardware/software capabilities; and they may observe different network loads. Allowing users distributed over a network to do collaborative work requires that they share and create multimedia objects and documents in an heterogeneous environment. Hence, the system must resolve the heterogeneity in the environment in order to allow users to collaborate. Here, I describe the Collaborative Heterogeneous Interactive Multimedia Platform (CHIMP) for distributed multimedia document authoring and presentation. A distributed multimedia document presentation involves retrieval of objects from one or more servers and their presentation at the client system. The retrieval and presentation of the multimedia objects has to be carried out in accordance with the specification of temporal and spatial relationships between the objects. The salient features of the CHIMP framework are flexible document specification, format conversions of media objects, and flexible object retrieval schedules for maximizing the document quality and handling variations in system parameters, such as network throughput and buffer resources.