Design of a storage and retrieval model for multimedia data.

Abstract

One of the most important and challenging aspects in multimedia technology is the design of a storage and retrieval system that will support the recording and the playback of multimedia data from a secondary storage device. This multimedia storage and retrieval system must be capable of handling discrete media (i.e. text, images and graphics) and continuous media (i.e. audio, video and animation). It should also provide facilities to handle the synchronization information between two or more data objects in a multimedia application. In this thesis, multimedia technology and its applications are first introduced followed by a review of multimedia requirements. An overview of the current storage and retrieval techniques for multimedia information is then given. Following, our storage model for multimedia data is presented. This model can support the storage of both discrete media and continuous media on a hard disk, it also offers methods to store the synchronization information of data objects on the disk. Unlike conventional data placement techniques, a special storage pattern is used in the model for the storage of continuous media streams. By using the storage pattern, real-time constraint can be guaranteed during the retrieval of a continuous media stream. A control scheme for simultaneous retrieval of multiple streams is then discussed in a single disk head system. The control scheme can guarantee the continuous retrieval of multiple streams simultaneously. By combining this control scheme with buffering techniques, a dynamic access control algorithm is developed to control the acceptance of the new retrieval request. Computer simulation is used to help the analysis of the storage model and the simultaneous retrieval control scheme. The results show that the storage and retrieval model can provide a good storage efficiency, and can guarantee the continuous retrieval of delay sensitive media streams.