Flash movie is gaining widespread usage nowadays. There are dozen of Flash movies now available throughout the Internet. In order to allow Flash movies to be queried, we create an OXF (Object XML for Flash) model by converting Flash movies into XML format. We apply Structural Join Index Hierarchy (SJIH) indexing technique to enhance retrieval of OXF objects. A detailed cost model for query execution through SJIH is developed. Our experimental studies on using SJIH based on Flash movies has demonstrated performance advantageous when compared with other indexing techniques.
In the context of multimedia retrieval, the goal of accuracy is to a certain extent contradictory with that of efficiency. The former relies on exploiting sophisticated features, whereas the latter favors using simple features with reduced dimensionality. As an endeavor to strike the balance between these two goals, this paper presents a self-adaptive semantic schema mechanism (SSM) for multimedia databases. The SSM is implemented based on an object-oriented data model, with classes being organized into a semantic hierarchy. As its most distinguishable feature, when the conditions of certain ECA-rules are satisfied, SSM supports adaptive evolution of a schema in the form of expansion with new classes and/or compaction by removing inefficient ones. This self-adaptive evolution strategy allows a schema to optimize for the requirements of each specific application, thereby achieving a dynamic, application-specific balance between accuracy and efficiency. A prototype system for multimedia retrieval, 2M2Net, has been built based on this mechanism and validated for its feasibility.
How to facilitate efficient video manipulation and access in a web-based environment is becoming a popular trend for video applications. In this paper, we present a web-oriented video management and application processing system, based on our previous work on multimedia database and content-based retrieval. In particular, we extend the VideoMAP architecture with specific web-oriented mechanisms, which include: (1) Concurrency control facilities for the editing of video data among different types of users, such as Video Administrator, Video Producer, Video Editor, and Video Query Client; different users are assigned various priority levels for different operations on the database. (2) Versatile video retrieval mechanism which employs a hybrid approach by integrating a query-based (database) mechanism with content- based retrieval (CBR) functions; its specific language (CAROL/ST with CBR) supports spatio-temporal semantics of video objects, and also offers an improved mechanism to describe visual content of videos by content-based analysis method. (3) Query profiling database which records the `histories' of various clients' query activities; such profiles can be used to provide the default query template when a similar query is encountered by the same kind of users. An experimental prototype system is being developed based on the existing VideoMAP prototype system, using Java and VC++ on the PC platform.