|Budget Amount *help
¥9,200,000 (Direct Cost : ¥9,200,000)
Fiscal Year 1993 : ¥900,000 (Direct Cost : ¥900,000)
Fiscal Year 1992 : ¥8,300,000 (Direct Cost : ¥8,300,000)
Recently, various types of very high-speed Local Area Networks have been proposed. Among them, FDDI (Fiber Distributed Data Interface) is the most promising one. At present, it is mainly used as back-bone LAN of Data Terminals. It has, however, the potential to be used as Multimedia LAN since its speed is enough affording the multimedia communication. From this point of view, we newly developed flow control algorithm to control the flow of multimedia signals, especially moving images and voices. We also studied the image coding technique matched with the above flow control.
First, we studied the constant rate moving image transimission using the asynchronous class of FDDI.We examined the relationship between the traffic and the threshold valuewhich defines the priority level of transmission. Then, we fined the network configuration, namely the number of stations, which can handle such a real time communication.
We also discussed the variable bit rate image transmission using the asynchrouns class. As a result we proposed a new algorithm in which the transmission of high priority image signals, which generally correspond to the low frequency signals, is guranteed even if the total traffic is very high.
For the image coding, we studid the sub-band coding, since it suits the priority control very well. For exmaple, we proposed various types of very short type filters. We also composed M channel filter banks in which M is not a power of two.