Audio/Video/Computer graphics synchronous reproducing/synthesizing system and method

Abstract

In an audio/video/computer graphics data synchronous reproducing/synthesizing system, a demultiplexer separates a bit stream in which an audio signal, a video signal, and computer graphics data are compressed and multiplexed, into compressed audio and video signal streams, audio and video signal time reference values, and a compressed computer graphics data stream. An audio PLL generates a first decoding clock. An audio decoder decodes the audio signal. An audio memory stores the decoded audio signal. A modulator modulates the audio signal in accordance with sound source control information. A video PLL generates a second decoding clock. A video decoder decodes the video signal. A video memory stores the decoded video signal. A CG decoder decodes the computer graphics data and event time management information. A CG memory stores the decoded computer graphics data. An event generator generates an event driving instruction. A detector detects viewpoint movement of an observer. A render engine receives the video signal, the computer graphics data, the event driving instruction, and viewpoint movement data and outputs a synthesized image of the video signal and the computer graphics data and the sound source control information. The method for this system is also disclosed.

1. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
 separation means for separating a bit stream in which an audio signal, a video signal, and computer graphics data are compressed and multiplexed, into a compressed audio signal stream, an audio signal time reference value, a compressed video signal, a video signal time reference value, and a compressed computer graphics data stream;  
 first clock generation means for generating a first decoding clock on the basis of the audio signal time reference value from said separation means;  
 first decoding means for decoding the audio signal from the compressed audio signal stream from said separation means and the first decoding clock from said first clock generation means;  
 first storage means for storing the decoded audio signal from said first decoding means;  
 modulation means for modulating the audio signal from said first storage means in accordance with sound source control information;  
 second clock generation means for generating a second decoding clock on the basis of the video signal time reference value from said separation means;  
 second decoding means for decoding the video signal from the compressed video signal stream from said separation means and the second decoding clock from said second clock generation means;  
 second storage means for storing the decoded video signal from said second decoding means;  
 third decoding means for decoding the computer graphics data and event time management information from the compressed computer graphics data stream from said separation means;  
 third storage means for storing the decoded computer graphics data from said third decoding means;  
 event generation means for generating an event driving instruction on the basis of the second decoding clock from said second clock generation means and the event time management information from said third decoding means;  
 detection means for detecting viewpoint movement of an observer using a pointing device; and  
 rendering means for receiving the video signal stored in said second storage means, the computer graphics data stored in said third storage means, the event driving instruction from said event generation means, and viewpoint movement data from said detection means, and outputting a synthesized image of the video signal and the computer graphics data and the sound source control information used by said modulation means.  
 
     
     
       2. An apparatus according to  claim 1 , further comprising:
 first buffer means for buffering the compressed audio signal stream from said separation means and outputting the compressed audio signal stream to said first decoding means;  
 second buffer means for buffering the compressed video audio stream from said separation means and outputting the compressed video signal stream to said second decoding means; and  
 third buffer means for buffering the compressed computer graphics data stream from said separation means and outputting the compressed computer graphics data stream to said third decoding means.  
 
     
     
       3. An apparatus according to  claim 1 , further comprising fourth storage means for storing the synthesized image of the video signal and the computer graphics data from said rendering means. 
     
     
       4. An apparatus according to  claim 3 , further comprising video deformation means for deforming the video signal from said second storage means on the basis of two-dimensional projection information of an object, and wherein
   said rendering means outputs the two-dimensional projection information of said object on which the video signal is mapped to said video deformation means, and    said fourth storage means overwrites the deformed video signal from said video deformation means on the synthesized image of the video signal and the computer graphics data from said rendering means and stores the synthesized image.    
 
     
     
       5. An apparatus according to  claim 1 , further comprising delay means for delaying the modulated audio signal from said modulation means. 
     
     
       6. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
 separation means for separating a bit stream in which an audio signal and a video signal are compressed and multiplexed, into a compressed audio signal stream, an audio signal time reference value, a compressed video signal stream, and a video signal time reference value;  
 first clock generation means for generating a first decoding clock on the basis of the audio signal time reference value from said separation means;  
 first decoding means for decoding the audio signal from the compressed audio signal stream from said separation means and the first decoding clock from said first clock generation means;  
 first storage means for storing the decoded audio signal from said first decoding means;  
 modulation means for modulating the audio signal from said first storage means in accordance with sound source control information;  
 second clock generation means for generating a second decoding clock on the basis of the video signal time reference value from said separation means;  
 second decoding means for decoding the video signal from the compressed video signal stream from said separation means and the second decoding clock from said second clock generation means;  
 second storage means for storing the decoded video signal from said second decoding means;  
 third decoding means for decoding computer graphics data and event time management information from a compressed computer graphics data stream which is not multiplexed with the compressed audio arid video signal streams;  
 third storage means for storing the decoded computer graphics data from said third decoding means;  
 event generation means for generating an event driving instruction on the basis of the second decoding clock from said second clock generation means and the event time management information from said third decoding means;  
 detection means for detecting viewpoint movement of an observer using a pointing device; and  
 rendering means for receiving the video signal stored in said second storage means, the computer graphics data stored in said third storage means, the event driving instruction from said event generation means, and viewpoint movement data from said detection means, and outputting a synthesized image of the video signal and the computer graphics data and the sound source control information used by said modulation means.  
 
     
     
       7. An apparatus according to  claim 6 , further comprising:
 first buffer means for buffering the compressed audio signal stream from said separation means and outputting the compressed audio signal stream to said first decoding means;  
 second buffer means for buffering the compressed video signal stream from said separation means and outputting the compressed video signal stream to said second decoding means; and  
 third buffer means for buffering the compressed computer graphics data stream which is not multiplexed with the compressed audio and video signal streams.  
 
     
     
       8. An apparatus according to  claim 6 , further comprising fourth storage means for storing the synthesized image of the video signal and the computer graphics data from said rendering means. 
     
     
       9. An apparatus according to  claim 8 , further comprising
 video deformation means for deforming the video signal from said second storage means on the basis of two-dimensional projection information of an object, and wherein 
 said rendering means outputs the two-dimensional projection information of said object on which the video signal is mapped to said video deformation means, and  
 said fourth storage means overwrites the deformed video signal from said video deformation means on the synthesized image of the video signal and the computer graphics data from said rendering means and stores the synthesized image.  
 
 
     
     
       10. An apparatus according to  claim 6 , further comprising delay means for delaying the modulated audio signal from said modulation means. 
     
     
       11. An audio/video/computer graphics data synchronous reproducing/synthesizing method, comprising the steps of:
 separating a bit stream in which an audio signal, a video signal, and computer graphics data are compressed and multiplexed, into compressed audio and video signal streams, audio and video signal identification reference values, and a compressed computer graphics data stream;  
 generating a signal clock from the audio and video identification reference values;  
 decoding the audio and video signals from the compressed audio and video signal streams; respectively, using the generated signal clock,  
 decoding event time reference information from the compressed computer graphics data stream, and  
 generating an event driving instruction from the generated signal clock and the decoded event time reference information to synchronize a synthesized image of the video signal and the computer graphics data with the audio signal.  
 
     
     
       12. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   an audio decoder decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        a video decoder decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        a computer graphics decoder decoding a compressed computer graphics data stream to produce computer graphics and event time management information;        an event generator generating an event driving instruction on the basis of said second timing information and said event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       13. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   a clock generator generating a first decoding clock and a second decoding clock on the basis of a signal time reference value;        an audio decoder decoding the compressed audio signal stream on the basis of said first decoding clock to produce an audio signal;        a video decoder decoding the compressed video signal stream on the basis of said second decoding clock to produce a video signal;        a computer graphics decoder decoding the compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating an event driving instruction on the basis of said second decoding clock and said event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       14. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   a demultiplexer receiving a compressed audio signal stream, a compressed video signal stream, a signal time reference value, and a compressed computer graphics data stream;        a clock generator generating a first decoding clock and a second decoding clock on the basis of the signal time reference value;        an audio decoder decoding the compressed audio signal stream on the basis of the first decoding clock to produce an audio signal;        a video decoder decoding the compressed video signal stream on the basis of the second decoding clock to produce a video signal;        a computer graphics decoder decoding the compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating an event driving instruction on the basis of the second decoding clock and the event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       15. An apparatus according to  claim 14 , further comprising:
   a modulator modulating the decoded audio signal in accordance with sound source control information,        wherein said rendering engine outputs the sound source control information used by said modulator.     
     
     
       16. An apparatus according to  claim 14 , further comprising:
   a viewpoint movement detector detecting viewpoint movement of an observer indicated by a pointing device;        wherein said rendering engine receives viewpoint movement data from said viewpoint movement detector.     
     
     
       17. An apparatus according to  claim 14 , further comprising:
   a video/computer graphics  ( CG )  memory storing the synthesized image of the decoded video signal and the decoded computer graphics data; and        a video deformation circuit deforming the video signal in said video/CG memory on the basis of two - dimensional projection information of an object,        wherein said rendering engine outputs the two - dimensional projection information of said object on which the video signal is mapped to said video deformation circuit, and        wherein said video/CG memory overwrites the deformed video signal fro said video deformation circuit on the synthesized image of the video signal and the computer graphics data from said rendering engine and stores the synthesized image.     
     
     
       18. A method of synchronously reproducing/synthesizing audio, video a computer graphics data comprising:
   decoding a compressed audio signal stream on the basis of a first timing information to produce an audio signal;        decoding a compressed video signal stream on the basis of a second timing information to produce a video signal;        decoding a compressed computer graphics data stream to produce computer graphics data and event time management information; and        generating an event driving instruction on the basis of said second timing information and said event time management information to synchronize the video signal with the computer graphics data.     
     
     
       19. A method of synchronously reproducing/synthesizing audio, video a computer graphics data comprising:
   generating a first decoding clock and a second decoding clock on the basis of a signal time reference value;        decoding a compressed audio signal stream on the basis of said first decoding clock to produce an audio signal;        decoding a compressed video signal stream on the basis of said second decoding clock to produce a video signal;        decoding a compressed computer graphics data stream to produce        generating an event driving instruction on the basis of said second decoding clock and said event time management information to synchronize the video signal with the computer graphics data.     
     
     
       20. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   receiving a compressed audio signal stream, a compressed video signal stream, a signal time reference value, and a compressed computer graphics data stream;        generating a first decoding clock and a second decoding clock on the basis of the signal time reference value;        decoding the compressed audio signal stream on the basis of the first decoding clock to produce an audio signal;        decoding the compressed video signal stream on the basis of the second decoding clock to produce a video signal;        decoding the compressed computer graphics data stream to produce computer graphics data and event time management information; and      generating an event driving instruction on the basis of the second decoding clock and the event time management information to synchronize the video signal with the computer graphics data.   
     
     
       21. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   an audio decoder decoding a compressed audio signal stream on the basis of an audio timestamp and a first decoding clock to produce an audio signal;        a video decoder decoding a compressed video signal stream on the basis of a video timestamp and a second decoding clock to produce a video signal;        a computer graphics decoder decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating an event driving instruction on the basis of said second decoding clock and said event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       22. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   a clock generator generating a first decoding clock on the basis of an audio clock reference, and generating a second decoding clock on the basis of a video clock reference;        an audio decoder decoding a compressed audio signal stream on the basis of an audio timestamp and said first decoding clock to produce an audio signal;        a video decoder decoding a compressed video signal stream on the basis of a video timestamp and said second decoding clock to produce a video signal;        a computer graphics decoder decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating an event driving instruction on the basis of said second decoding clock and said event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       23. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   a demultiplexer receiving a compressed audio signal stream, a compressed video signal stream, an audio clock reference, a video clock reference, an audio timestamp, a video timestamp and a compressed computer graphics data stream;        a clock generator generating a first decoding clock on the basis of said audio clock reference, and generating a second decoding clock on the basis of the video clock reference;        an audio decoder decoding the compressed audio signal stream on the basis of the audio timestamp and the first decoding clock to produce an audio signal;        a video decoder decoding the compressed video signal stream on the basis of the video timestamp and the second decoding clock to produce a video signal;        a computer graphics decoder decoding the compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating an event driving instruction on the basis of the second decoding clock and the event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       24. An apparatus according to  claim 23 , further comprising:
   a modulator modulating the decoded audio signal in accordance with sound source control information,        wherein said rendering engine outputs the sound source control information used by said modulator.     
     
     
       25. An apparatus according to  claim 23 , further comprising:
   a viewpoint movement detector detecting viewpoint movement of an observer indicated by a pointing device;        wherein said rendering engine receives viewpoint movement data from said viewpoint movement detector.     
     
     
       26. An apparatus according to  claim 23 , further comprising:
   a video/computer graphics  ( CG )  memory storing the synthesized image of the decoded video signal and the decoded computer graphics data; and        a video deformation circuit deforming the video signal in said video/CG memory on the basis of two - dimensional projection information of an object,        wherein said rendering engine outputs the two - dimensional projection information of said object on which the video signal is mapped to said video deformation circuit, and        wherein said video/CG memory overwrites the deformed video signal from said video deformation circuit on the synthesized image of the video signal and the computer graphics data from said rendering engine and stores the synthesized image.     
     
     
       27. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   decoding a compressed audio signal stream on the basis of an audio timestamp and a first decoding clock to produce an audio signal;        decoding a compressed video signal stream on the basis of a video timestamp and a second decoding clock to produce a video signal;        decoding a compressed computer graphics data stream to produce computer graphics data and event time management information; and        generating an event driving instruction on the basis of said second decoding clock and said event time management information to synchronize the video signal with the computer graphics data.     
     
     
       28. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   generating a first decoding clock on the basis of an audio clock reference, and generating a second decoding clock on the basis of a video clock reference;        decoding a compressed audio signal stream on the basis of an audio timestamp and said first decoding clock to produce an audio signal;        decoding a compressed video signal stream on the basis of a video timestamp and said second decoding clock to produce a video signal;        decoding a compressed computer graphics data stream to produce computer graphics data and event time management information; and        generating an event driving instruction on the basis of said second decoding clock and said event time management information to synchronize the video signal with the computer graphics data.     
     
     
       29. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   receiving a compressed audio video stream, a compressed video signal stream, an audio clock reference, a video clock reference, an audio timestamp, a video timestamp and a compressed computer graphics data stream;        generating a first decoding clock on the basis of the audio clock reference, and for generating a second decoding clock on the basis of the video clock reference;        decoding the compressed audio signal stream on the basis of the audio timestamp and the first decoding clock to produce an audio signal;        decoding the compressed video signal stream on the basis of the video timestamp and the second decoding clock to produce a video signal;        decoding the compressed computer graphics data stream to produce computer graphics data and event time management information; and        generating an event driving instruction on the basis of the second decoding clock and the event time management information to synchronize the video signal with the computer graphics data.     
     
     
       30. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   a demultiplexer receiving a compressed audio signal stream, a compressed video signal stream, a signal time reference value, and a compressed computer graphics data stream;        an audio decoder decoding the compressed audio signal stream on the basis of the signal time reference value to produce an audio signal;        a video decoder decoding the compressed video signal stream on the basis of the signal time reference value to produce a video signal;        computer graphics decoder decoding the compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating, in synchronism with said video decoder, an event driving instruction on the basis of the event time management information; and        rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       31. An audio/video/computer graphics data synchronous reproducing/synthesizing system according to  claim 30 , wherein said video decoder and said event generator use the same decoding clock. 
     
     
       32. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   a demultiplexer receiving a compressed audio signal stream, a compressed video signal stream, audio clock reference, video clock reference, an audio timestamp, a video timestamp and a compressed computer graphics data stream;        an audio decoder decoding the compressed audio signal stream on the basis of the audio timestamp and the audio clock reference to produce an audio signal;        a video decoder decoding the compressed video signal stream on the basis of the video timestamp and the video clock reference to produce a video signal;        a computer graphics decoder decoding the compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating, in synchronism with said video decoder, an event driving instruction on the basis of the event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       33. An audio/video/computer graphics data synchronous reproducing/synthesizing system according to  claim 32 , wherein said video decoder and said event generator use the same decoding clock. 
     
     
       34. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   a demultiplexer receiving a compressed audio signal stream, a compressed video signal stream, audio clock reference, video clock reference, an audio timestamp, a video timestamp and a compressed computer graphics data stream;        a clock generator generating a first decoding clock on the basis of said audio clock reference, and generating a second decoding clock on the basis of the video clock reference;        an audio decoder decoding the compressed audio signal stream on the basis of the audio timestamp and the first decoding clock to produce an audio signal;        a video decoder decoding the compressed video signal stream on the basis of the video timestamp and the second decoding clock to produce a video signal;        a computer graphics decoder decoding the compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating, in synchronism with said video decoder, an event driving instruction on the basis of the event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       35. An audio/video/computer graphics data synchronous reproducing/synthesizing system according to  claim 34 , wherein said video decoder and said event generator use the same decoding clock. 
     
     
       36. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   receiving a compressed audio signal stream, a compressed video signal stream, a signal time reference value, and a compressed computer graphics data stream;        decoding the compressed audio signal stream on the basis of the signal time reference value to produce an audio signal;        decoding the compressed video signal stream on the basis of the signal time reference value to produce a video signal;        decoding the compressed computer graphics data stream to produce computer graphics data and event time management information; and        generating an event driving instruction on the basis of the event time management information to synchronize the video signal with the computer graphics data.     
     
     
       37. A method according to  claim 36 , wherein decoding the compressed video signal stream and generating an event driving instruction use the same decoding clock. 
     
     
       38. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   receiving a compressed audio video stream, a compressed video signal stream, an audio clock reference, a video clock reference, an audio timestamp, a video timestamp and a compressed computer graphics data stream;        decoding the compressed audio signal stream on the basis of the audio timestamp and the audio clock reference to produce an audio signal;        decoding the compressed video signal stream on the basis of the video timestamp and the video clock reference to produce the video signal;        decoding the compressed computer graphics data stream to produce computer graphics data and event time management information; and        generating an event driving instruction on the basis of the event time management information to synchronize the video signal with the computer graphics data.     
     
     
       39. A method according to  claim 38 , wherein decoding the compressed video signal stream and generating an event driving instruction use the same decoding clock. 
     
     
       40. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   receiving a compressed audio signal stream, a compressed video signal stream, an audio clock reference, a video clock reference, an audio timestamp, a video timestamp and a compressed computer graphics data stream;        generating a first decoding clock on the basis of the audio clock reference, and generating a second decoding clock on the basis of the video clock reference;        decoding the compressed audio signal stream on the basis of the audio timestamp and the first decoding clock to produce an audio signal;        decoding the compressed video signal stream on the basis of the video timestamp and the second decoding clock to produce a video signal;        decoding the compressed computer graphics data stream to produce computer graphics data and event time management information; and        generating an event driving instruction on the basis of the event time management information to synchronize the video signal with the computer graphics data.     
     
     
       41. A method according to  claim 40 , wherein decoding the compressed video signal stream and generating an event driving instruction use the same decoding clock. 
     
     
       42. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   a demultiplexer receiving a compressed audio signal stream, a compressed video signal stream, and a compressed computer graphics data stream;        an audio decoder decoding the compressed audio signal stream to produce an audio signal;        a video decoder decoding the compressed video signal stream to produce a video signal;        a computer graphics decoder decoding the compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating, in synchronism with said video decoder, an event driving instruction on the basis of the event time management information; and        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data.     
     
     
       43. An audio/video/computer graphics data synchronous reproducing/synthesizing system according to  claim 42 , wherein said video decoder and said event generator use the same decoding clock. 
     
     
       44. A method of synchronously reproducing/synthesizing audio, video and computer graphics data, comprising:
   receiving a compressed audio signal stream, a compressed video signal stream, and a compressed computer graphics data stream;        decoding the compressed audio signal stream to produce an audio signal;        decoding the compressed video signal to produce a video signal;        decoding the compressed computer graphics data stream to produce computer graphics data and event time management information; and        generating an event driving instruction on the basis of the event time management information to synchronize the video signal with the computer graphics data.     
     
     
       45. A method according to  claim 44 , wherein decoding the compressed video signal stream and generating an event driving instruction use the same decoding clock. 
     
     
       46. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   an audio decoder decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        a video decoder decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        a computer graphics decoder decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating, in synchronism with the video decoder, an event driving instruction on the basis of said event time management information;        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data; and        a video deformation circuit for deforming the decoded video signal in accordance with two - dimensional projection information provided by the rendering engine.     
     
     
       47. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   an audio decoder decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        a video decoder decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        a computer graphics decoder decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating an event driving instruction on the basis of said second timing information and said event time management information;        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data; and        a video deformation circuit for deforming the decoded video signal in accordance with two - dimensional projection information provided by the rendering engine.     
     
     
       48. A method of synchronously reproducing/synthesizing audio, video and computer graphics data, comprising:
   decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        generating an event driving instruction on the basis of said event time management information to synchronize the video signal with the computer graphics data;        deforming the decoded video signal in accordance with two - dimensional projection information; and        outputting a synthesized image of the video signal and the computer graphics data, wherein the synthesized image includes a deformed video image.     
     
     
       49. A method of synchronously reproducing/synthesizing audio, video and computer graphics data, comprising:
   decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        generating an event driving instruction on the basis of said second timing information and said event time management information to synchronize the video signal with the computer graphics data;        deforming the decoded video signal in accordance with two - dimensional projection information; and        outputting a synthesized image of the video signal and the computer graphics data, wherein the synthesized image includes a deformed video image.     
     
     
       50. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   an audio decoder decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        a video decoder decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        a computer graphics decoder decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating, in synchronism with said video decoder, an event driving instruction on the basis of said event time management information;        a rendering engine received the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data; and        an audio delay circuit for delaying the output of said audio signal in accordance with a rendering delay signal provided by the rendering engine.     
     
     
       51. An audio/video/computer graphics data synchronous reproducing/synthesizing system comprising:
   an audio decoder decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        a video decoder decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        a computer graphics decoder decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        an event generator generating an event driving instruction on the basis of said second timing information and said event time management information;        a rendering engine receiving the decoded video signal, the decoded computer graphics data and the event driving instruction, to output a synthesized image of the video signal and the computer graphics data; and        an audio delay circuit for delaying the output of said audio signal in accordance with a rendering delay signal provided by the rendering engine.     
     
     
       52. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        generating an event driving instruction on the basis of said event time management information to synchronize the video signal with the computer graphics data;        generating an audio delay signal in accordance with a rendering delay of a rendering engine;        outputting a synthesized image of the video signal and the computer graphics data; and        outputting a delayed audio signal in accordance with the audio delay signal such that the delayed audio signal is synchronized with the synthesized image of the video signal and the computer graphics data.     
     
     
       53. A method of synchronously reproducing/synthesizing audio, video and computer graphics data comprising:
   decoding a compressed audio signal stream on the basis of first timing information to produce an audio signal;        decoding a compressed video signal stream on the basis of second timing information to produce a video signal;        decoding a compressed computer graphics data stream to produce computer graphics data and event time management information;        generating an event driving instruction on the basis of said second timing information and said event time management information to synchronize the video signal with the computer graphics data;        generating an audio delay signal in accordance with a rendering delay of a rendering engine;        outputting a synthesized image of the video signal and the computer graphics data; and        outputting a delayed audio signal in accordance with the audio delay signal such that the delayed audio signal is synchronized with the synthesized image of the video signal and the computer graphics data.