Version management for multimedia document retrieval systems

This thesis presents a mechanism which supports the management of the versions of multimedia documents, their subparts, structures and indexes in a multimedia document retrieval system (MDRS). The version mechanism provides a naming scheme of the versions of the objects, a version derivation model, and a composition mechanism. The version mechanism also supports efficient storage of the versions of structures. Since multimedia is a rather new research area, its structural aspects have not received much attention. However, recent research shows that the structural aspects of a multimedia document are important in storage and retrieval of multimedia documents, film editing, preparation of multimedia document presentation, etc. Thus, this thesis focuses on the structural aspects of MDRS version management. The derivation model supports modeling of the version history of the multimedia document structure. It also specifies the properties of the versions of the multimedia document structure. Based on the derivation model, a set of history browsing operators for multimedia document objects, including structures, are defined so that various versions in an MDRS can be retrieved. It is unique since it supports the retrieval of the structural versions and can be combined with multimedia document query statements. The proposed composition mechanism extends the representation scheme of multimedia document structures by allowing specification of the identifiers of multimedia document objects and their versions. The storage mechanism proposes a structure delta storage method which supports efficient storage of the versions of the multimedia document structure. Since conventional delta storage mechanisms have concentrated on the delta information in textual document content, the structure delta method could be an important addition to the research of the MDRS version management. A version mechanism is described for indexes that have weighting factors. While the previous version mechanisms store addition or removal of an entity with respect to a keyword, our model stores whole reference list whose weighting factors for entities have been changed for a keyword. Although more delta storage space is required, it can store all the changed information which cannot be captured by the previous mechanisms. A delta storage mechanism for raw multimedia data is left for future research