Building and Indexing a Distributed Multimedia Presentation Archive Using SMIL

This paper proposes an approach to the problem of generating metadata for composite mixed-media digital objects by appropriately combining and exploiting existing knowledge or metadata associated with the individual atomic components which comprise the composite object. Using a distributed collection of multimedia learning objects, we test this proposal by investigating mechanisms for capturing, indexing, searching and delivering digital online presentations using SMIL (Synchronized Multimedia Integration Language). A set of tools have been developed to automate and streamline the construction and fine-grained indexing of a distributed library of digital multimedia presentation objects by applying SMIL to lecture content from both the University of Qld and Cornell University. Using temporal information which is captured automatically at the time of lecture delivery, the system can automatically synchronize the video of a lecture with the corresponding Powerpoint slides to generate a finely-indexed presentation at minimum cost and effort. This approach enables users to search and retrieve relevant streaming video segments of the lecture based on keyword or free text searches within the slide content. The underlying metadata schema, the metadata processing/generation tools, distributed archive, backend database and the search, browse and playback interfaces which comprise the system are also described in this paper. We believe that the relatively low cost and high speed of development of this apparently sophisticated multimedia archive with rich search capabilities, provides evidence to support the validity of our initial proposal.