Video transmission system

Abstract

In a video transmission system which transmits video data through a network, the network sets up fixed virtual connections between transmitters and a receiver. In the receiver, a connection control portion designates a desired one of the virtual connections and a header controller only extracts packets of the designated virtual connection.

What we claim is:  
     
         1 . A video transmission system comprising: 
 transmitters in which video data from a plurality of video data generators are encoded, packetized and outputted; 
 a network which transmits the packetized video data;  
 a receiver in which the packetized video data received through the network is de-packetized, decoded and outputted; and  
 a display unit which displays the video data, wherein 
 the network providing fixed virtual connections between the transmitters and the receiver, and  
 the receiver including; 
 a connection control portion for designating a desired one of the virtual connections, and  
 a header controller which only extracts packets of the designated virtual connection.  
 
 
   
     
     
         2 . A video transmission system as claimed in  claim 1  wherein the receiver further includes a connection information memory which has stored the virtual connections to be read out in a predetermined order, and 
 the connection control portion reads out the virtual connection stored in the connection information memory based on an externally designated connection signal, and designates the virtual connection to the header controller.  
 
     
     
         3 . A video transmission system as claimed in  claim 1  wherein the receiver further includes a connection information memory which has stored the virtual connections to be read out in a predetermined order, and 
 the connection control portion reads out the virtual connection stored in the connection information memory at every external input timing, and designates the virtual connection to the header controller.  
 
     
     
         4 . A video transmission system as claimed in  claim 1  wherein the virtual connection is designated by a virtual path identifier or a virtual channel identifier which is included in the packet.  
     
     
         5 . An apparatus in which packetized video data received through a network providing fixed virtual connections are de-packetized, decoded and outputted, comprising: 
 a connection control portion for designating a desired one of the virtual connections; and    a header controller which only extracts packets of the designated virtual connection.    
     
     
         6 . A video transmission method comprising the steps of: 
 encoding, packetizing, and transmitting video data;    receiving, de-packetizing, and decoding the packetized video data received through a network providing fixed virtual connections;    designating a desired one of the virtual connections; and    extracting only packets of the designated virtual connection.