Storage Allocation Policies for Time-Dependent Multimedia Data

{Multimedia computing requires support for heterogeneous data types with differing storage, communication, and delivery requirements. Continuous media data types such as audio and video impose delivery requirements that are not satissed by conventional physical storage organizations. In this paper we describe a physical organization for multi-media data based on the need to support the delivery of multiple playout sessions from a single rotating-disk storage device. Our model relates disk characteristics to the diierent media recording and playback rates and derives their storage pattern. This storage organization guarantees that as long as a multimedia delivery process is running, starvation will never occur. Furthermore, we derive bandwidth and buuer constraints for disk access and present an approach to minimize latencies for non-continuous media stored on the same device. The analysis and numerical results indicate the feasibility of using conventional rotating magnetic disk storage devices to support multiple sessions for on-demand video applications.