INTERVAL-BASED CONCEPTUAL MODELS FOR TIME-DEPENDENT MULTIMEDIA DATA

Multimedia data often have time dependencies that must be satisfied at presentation time. To support a general-purpose multimedia information system, these timing relationships must be managed to provide utility to both the data presentation system and the multimedia author. In this paper we propose new conceptual models for capturing these timing relationships and managing them as part of a database. Specifically, we introduce and define n-ary and reverse temporal relations along with their temporal constraints. These new relations are a generalization of our earlier temporal models and establish the basis for conceptual database structures and temporal access control algorithms to facilitate forward, reverse, and partial-interval evaluation during multimedia object playout. The proposed relations are defined to ensure a property of monotonically increasing playout deadlines to facilitate both real-time deadline-driven playout scheduling or optimistic interval-based process playout. Furthermore, we show a translation of the conceptual models to a structure suitable for a relational database.