Showing papers by "Katsumi Tanaka published in 1997"

A SOM-Based Information Organizer for Text and Video Data

Abstract: We propose an information organizer for e ective clustering and similarity-based retrieval of text and video data. Instead of giving keywords or authoring them, we use a vector space model and DCT image coding in order to extract characteristics of data. Data are clustered by Kohonen's self-organizing map, and the result is visualized in a 3D form. By this, similarity-based retrieval is achieved. We implemented a prototype system and report experimental results. We consider that our system e ectively promotes reuse of distributed text and image data assets.

Spatial Views and LOD-Based Access Control in VRML-object Databases

Abstract: VRML is a language to describe virtual 31) spaces. In order to achieve reuse and sharing of data described in VRML among multiple applications, we designed and implemented a VRML-object database system. In our system, we can add semantic information onto VRML data, and can issue queries by using that information. We also introduce the concepts of spatial view and level-of-detail based access control. When a user issues a query, the system produces a spatial view by reorganizing a virtual space in accordance with the user's concern and the user's access capability.

A Time-Stamped Authoring Graph for Video Databases

Abstract: This paper presents a “time-stamped authoring graph”, which is a new video description model and retrieval method based on fragmentary descriptions of video contents (i.e., the authors' impressions or feelings) and their relationships. It. can handle continuous video images better than existing description models, which tend to have problems in extracting parts of continuous video images and giving them precise descriptions. A video retrieval algorithm using a time-stamped authoring graph is explained, and the criteria for selecting or ranking the retrieved video images are discussed. The design and implementation of the prototype for video description and retrieval interfaces are also described and examined, with some examples.

Encapsulating Multimedia Contents and a Copyright Protection Mechanism into Distributed Objects

Abstract: We proposed an Encapsulated Multimedia Object (EMO) for the copyright protection. EMO as a Java applet is independent of computer hardware and operating systems. Also, it can control its view for each user. An EMO displays a complete image for a legal user. However, it displays an incomplete image for an illegal user. We developed a copyright protection prototype system by EMO and tested it. We found several useful features and also some limitations. Presently, we are redesigning the EMO and EMO database system. Also, we reported their concepts.

Virtual channel: dynamic structuring and continuous queries for data on the air

Abstract: This paper proposes a restructuring method for data via digital video satellite broadcasting systems. The research is motivated by development of the EPG (electronic television program guide) system for browsing through the content of a few hundred channels. It is not possible for users to check each piece of data all the time. We propose a new approach to reorganize the EPG data for retrieving the desired television program information instead of a system-defined EPG.