Multimedia System

1. Preface (26 KB)

---[Hiromu Hayashi,General Manager Multimedia Systems Laboratories. ]

2.Quality Control Scheme for ATM Switching Network (119 KB)

In an ATM network, there are many kinds of calls which require various qualities. A method is required to control the connection and cell administration according to the required Quality of Service (QoS) for each connection. In this paper, we propose the Quality Control Path (QCP) concept to control the qualities of the established connections in the ATM switch. With this method, the buffers and the capacities of the physical links in the switch are each divided into logical paths. We also described a control scheme to maintain a required QoS for each connection. ---[Masafumi Katoh, Takeshi Kawasaki, Satoshi Kakuma ]

3. Broadband Intelligent Network Architecture for Multimedia-on-Demand Service (105 KB)

This paper proposes a broadband ISDN (B-ISDN) oriented intelligent network (IN) architecture for a multimedia-on-demand (MOD) service. It demonstrates that IN architecture is effective for MOD service control. Then, this paper proposes an IN call model for B-ISDN, which is an essential model for defining an open interface in the IN architecture. The proposed call model can be applied not only to MOD service control, but to control of more advanced B-ISDN multimedia services. Also, an example of MOD service control based on the proposed IN architecture is given. ---[Masaaki Wakamoto, Mitsunori Fukazawa ]

4. Internet Simulator for Testing Networked Multimedia (245 KB)

In developing multimedia applications for the Internet, a simulation tool is essential in evaluating the effectiveness of various transmission schemes. We have built such a tool, which uses queueing systems to model network switching nodes. It enables users to control the degree of (simulated) network congestion so that applications can be tested under different traffic conditions. In addition, the tool facilitates subjective testing of continuous signals in real time, so that the percentual signal quality can be evaluated while network simulation is being run. This feature distinguishes the tool from traditional network simulators. ---[Yao-Min Chen ]

5. Experiments of Real-Time MPEG Audio over the Internet (121 KB)

This paper reports the development of audio-on-demand system operating across the Internet. A shorter version of the report can be found in Ref.1). The software-only real-time playback system uses the MPEG-1 Audio format as compression method and a client-server architecture was assumed. To ensure the quality of playback under adverse network conditions of the Internet, packet-level interleaving and loss compensation were implemented. Two approaches were taken to test the performance of the system; first by continually trafficking the packets over the Internet and secondly by connecting to a network simulator with suitable competing traffic. The network simulator is very useful in stadying the behavior of the system with more control of the desired conditions and without interrupting the actual network. Further work was done to incorporate forward correction codes to improve the performance under severe network congestion. ---[Jey-Hsin Yao, Yao-Min Chen]

6. A Prototype Multimedia Database System (112 KB)

Emerging multimedia applications such as digital libraries and document management require new databases. Next-generation database systems must enable users to efficiently and flexibly develop and execute such advanced multimedia applications. In this paper, we focus on the development of a database system which enables flexible and efficient acquisition, storage, access, retrieval, distribution, and presentation of large amounts of heterogeneous media data. We take the approach of extending an object-oriented database, which is more suitable for describing media structures and operations than a traditional relational database. In this paper, we describe a multimedia data model and its efficient implementation. ---[Hiroshi Ishikawa ]

7. High Speed CG and Simulation Application Development Environment "Firstsight" (245 KB)

Recently, the efficient development of software is becoming more and more important as multimedia technology progresses. In particular, software for creating and simulating images based on three-dimensional computer graphics requires an increasing number of man-hours to develop. This development process must be reconsidered from the viewpoint of reusing software components. No one has, however, suceeded in developing reusable software components that offer both general-purpose applicability and high-speed processing. The authors have developed a computer graphics and simulation application development environment which allows the application designer to reuse software components with high-speed processing and time control capabilities. This environment is named "Firstsight". The basic concept of the Firstsight system is software LSI. It is an improved concept of constructing componentware based on the concepts of object-oriented and data flow programming. Software LSIs bear many similarities to hardware LSIs. This is a totally new method of constructing realtime applications. ---[Fumio Nagashima, Kaori Suzuki, Tsugito Maruyama ]

8. 3D-CG System with Video Texturing for Personal Computers (178 KB)

Three-dimensional computer graphics (3D-CG) is attracting attention as an Internet multimedia technology. We have developed a 3D-CG system with video texturing for personal computers. First we developed a high-performance rendering LSI chip to reduce the size and cost of the system. This chip can handle 400 k polygons/s and 15 M texture cells/s. We then developed a personal computer accelerator board that incorporates the LSI rendering chip. In addition, we extended certain functions to enable video images to be entered as texture data and confirmed the effectiveness of the system through application trials. ---[Toru Ozaki, Tatsushi Otsuka, Seiya Shimizu ]

9. Information Sharing Using WWW in WHIST (486 KB)

Document information sharing has become important to cope with the increasing amount of digital documents in the information network society. We developed WHIST (Web-Human Information Seeking Tools) as an environment to share, retrieve, and organize document information in an intranet. There are two processes in document information sharing in WHIST: document sharing and information retrieval. WHIST integrates and shares documents such as e-mail, news, and HTMLs bottom-up using the WWW. WHIST also provides various information retrieval methods to shared documents including full-text document searching, user adaptation, and multiple views based on the information extraction using natural language processing. ---[Hiroshi Tsuda, Kanji Uchino, Kunio Matsui ]

10. Single-Hand Input Scheme for English and Japanese Text (93 KB)

This paper introduces a new high-speed input scheme for mobile computers that is operated with a single hand. The new scheme consists of our Single Hand Keys (SHK) keycard, associated ambiguity resolution logic, and other support programs. This input scheme can be used for both English and Japanese text. First we explain the background of our research, then we describe the design and operation of the SHK scheme. ---[Masakatsu Sugimoto ]

11. A Multi-Agent Approach to a Distributed Schedule Management System (422 KB)

More and more people are engaging in cooperative team activities over worldwide networks such as the Internet. The multi-agent technology is a framework suitable for constructing distributed applications to support these activities. Systems based on this framework have the necessary autonomy, independency, flexibility, and extensibility. We have focussed on the distributed schedule management, which is a typical application of the multi-agent technology. We have developed a system, intelliDiary, based on this framework to show how the framework is used and how the characteristics of the framework enhance the functions of destributed applications. ---[Yuji Wada, Masatoshi Shiouchi, Yuji Takada]