Client/server multimedia presentation system

Abstract

A method of presenting, at a client terminal, a video program stored in a server linked with the client terminal via transmission path of a limited transmission band width. Each frame of the video program comprises a basic data portion and at least one level of quality supplement data portions. In the method, in response to one of play control commands from a user, the client terminal determines a start position in the video program according to the issued play control command. The play control commands includes a play, a stop, a head search, a jump forward and a jump backward command. In response to the issued play command, the terminal obtains and uses the basic data portions for playing the video program. In response to the stop command, the terminal obtains the quality supplement data portions for the last displayed frame and uses them for displaying a quality-enhanced version of the last displayed frame.

1 . A method of presenting, at a client terminal, a video program stored in a server linked with the client terminal, the method comprising the steps of: 
 preparing a plurality of levels of quality supplement data in the server as each of a plurality of quality supplement data portions;    storing a plurality of basic data portions on a recording medium in the server;    storing each level of the quality supplement data on a recording medium in the server;    preparing one basic data portion and one quality supplement data portion for each frame of the video program in the server, a quality of the video program at each frame played based on a combination of the basic data portion and the quality supplement data portion being higher than that based on only the basic data portion;    in response to a play command in the client terminal, obtaining the basic data portions of the frames of the video program needed to play the video program by using the basic data portions of the frames; and    in response to a stop command in the client terminal, adding the quality supplement data portion of the last displayed frame to display a quality-enhanced version of the last displayed frame by using a combination of the basic data portion and the quality supplement data portion    
   
   
       2 . A method as defined in  claim 1 , further comprising the step of, in response to one of a head search command, a jump forward command and a jump backward commands in the client terminal, adding the quality supplement data portion, of the last displayed frame to display the quality-enhanced version of said last displayed frame by using the combination of the basic data portion and the quality supplement data portion.  
   
   
       3 . (canceled)  
   
   
       4 . A method as defined  claim 1 , further comprising the steps, executed by said server, of: 
 moving the recording media synchronously in any of a play operation, a head search operation, a jump forward operation or a jump backward operation; and    in response to a quality supplement data request from said client terminal, sending at least one level of quality supplement data of the last displayed frame to the client terminal by reading the level of the quality supplement data while synchronously moving the recording media, wherein the quality supplemental data request are prepared in response to the stop command.    
   
   
       5 - 9 . (canceled)  
   
   
       10 . A method as defined in  claim 1 , wherein each frame of the video program has been coded according to a coding standard, wherein the program comprises independent frames that can be decoded alone without the a need of other frame data and different frames that can not be decoded without other frame data, and wherein the step of obtaining the basic data portions said using includes passing to a decoder, and the step of adding the quality supplement data portion includes passing the quality supplement data portion to the decoder.  
   
   
       11 . A method as defined in  claim 10 , wherein said coding standard is an H.263 standard, the step of obtaining the basic data portions includes passing the basic data portions to an H.263 decoder, and the step of adding the quality supplement data portion includes passing the quality supplement data portion to the H.263 decoder.  
   
   
       12 . A method as defined in  claim 10 , wherein the coding standard is an MPEG standard, the step of obtaining the basic data portions includes passing the basic data portions to an MPEG decoder, and the step of adding the quality supplement data portion includes passing the quality supplement data portion to the MPEG decoder.  
   
   
       13 - 33 . (canceled)  
   
   
       34 . A method as defined in  claim 1 , wherein the step of adding said supplement data portion comprises: 
 providing a plurality of levels of quality supplement data; and    applying each level of quality supplement data in sequence to gradually increase the quality of the video program at the last displayed frame played by a combination of the basic data portion and the level of quality supplement data.    
   
   
       35 . A method as defined in  claim 1  wherein said recording medium is a tape recording medium.  
   
   
       36 . A method as claimed in  claim 1  wherein said recording medium comprises a plurality of recording media.  
   
   
       37 . A method as claimed in  claim 35  wherein said recording media comprise a plurality pf tape recording media.