COLLABORATIVE MULTIMEDIA DOCUMENTS - AUTHORING AND PRESENTATION

Multimedia documents are composed of different data types such as vide o, audio, text, and images. Authoring a multimedia document is a creat ive exercise. Unlike traditional computer supported collaborative work where documents are composed of static objects, multimedia documents have temporal and spatial requirements that must be supported by any c ollaborative multimedia platform. In this paper, we show that most req uirements (including temporal and spatial) for collaborative multimedi a authoring systems can be expressed in terms of a highly structured c lass of linear constraints called prioritized difference constraints. Based on our prioritized difference constraint-based characterization, we develop efficient, incremental algorithms for creating and modifyi ng multimedia documents so as to satisfy the required temporal and spa tial constraints. We further develop methods to identify inconsistent requirements, and show how such inconsistencies may be removed through constraint relaxation techniques. We also report on the collaborative heterogeneous interactive multimedia platform (CHIMP) system develope d using the framework described. (C) 1998 John Wiley & Sons, Inc.