System and method for effectively performing an audio/video synchronization procedure

• US 7,120,168 B2
• Filed: 11/20/2001
• Issued: 10/10/2006
• Est. Priority Date: 11/20/2001
• Status: Active Grant

• Current Assignee: Saturn Licensing LLC (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Zimmermann, Klaus
• Primary Examiner(s): Ngo, Ricky Q.
• Assistant Examiner(s): LEE, ANDREW CHUNG CHEUNG
• Application Number:
  US09/989,560
• Publication Number:
  US 20030095574A1
• Time in Patent Office: 1,785 Days
• Field of Search: 370/486, 370/498, 370/473, 370/412, 370/503, 370/464, 370/100.1
• US Class Current: 370/503
• CPC Class Codes: H04N 21/4305 Synchronising client clock from received content stream, e.g. locking decoder clock with encoder clock, extraction of the PCR packets arrangements for synchronising receiver with transmitter by comparing receiver clock with transmitter clock H04L7/0012; arrangements for synchronising receiver with transmitter wherein the receiver takes measures against momentary loss of synchronisation H04L7/0083
• CPC Class Codes: H04N 21/43072 of multiple content streams on the same device
• CPC Class Codes: H04N 21/4341 Demultiplexing of audio and video streams

Abstract

A system and method for effectively performing an audio/video synchronization procedure in a receiver device may preferably include a demultiplexer configured to recover elementary bitstreams from a multiplexed bitstream. The demultiplexer may also preferably extract decode timestamps and output timestamps corresponding to the elementary bitstreams. One or more decoders may then decode the elementary bitstreams to produce decoded frames in accordance with the foregoing decode timestamps. One or more output modules may then process the decoded frames to produce processed frames in accordance with the output timestamps. In accordance with the present invention, an output controller may preferably perform an output timing resynchronization procedure following a program change event to align output timings of the processed frames in accordance with new output timestamps from the selected program.

Claims

1. A system for performing a data synchronization procedure, comprising:

a demultiplexer configured to recover elementary bitstreams, and to extract decode timestamps and output timestamps corresponding to said elementary bitstreams;

one or more decoders configured to .decode said elementary bitstreams to produce decoded frames;

an input controller configured to control said one or more decoders according to said decode timestamps;

one or more output modules configured to process said decoded frames to produce processed frames; and

an output controller configured to control said one or more output modules according to said output timestamps, said output controller performing an output timing resynchronization procedure to align output frame timings of said processed frames according to said output timestamps, said data synchronization procedure being performed by a receiver device that receives a multiplexed bitstream from a data source and responsively generates said processed frames to one or more destination devices, said one or more elementary bitstreams including a video bitstream and an audio bitstream, said one or more decoders including a video decoder and an audio decoder, said one or more output modules including a video output module and an audio output module, said output timing resynchronization procedure being performed after receiving new output timestamps as a result of a program change event.

2. A system for performing a data synchronization procedure, comprising:

a demultiplexer configured to recover elementary bitstreams, and to extract decode timestamps and output timestamps corresponding to said elementary bitstreams;

one or more decoders configured to decode said elementary bitstreams to produce decoded frames;

an input controller configured to control said one or more decoders according to said decode timestamps;

one or more output modules configured to process said decoded frames to produce processed frames; and

an output controller configured to control said one or more output modules according to said output timestamps, said output controller performing an output timing resynchronization procedure to align output frame timings of said processed frames according to said output timestamps, said data synchronization procedure being performed by a receiver device that receives a multiplexed bitstream from a data source and responsively generates said processed frames to one or more destination devices, said one or more elementary bitstreams including a video bitstream and an audio bitstream, said one or more decoders including a video decoder and an audio decoder, said one or more output modules including a video output module and an audio output module, a system user instructing said receiver device to select a new program, said receiver device responsively performing a program search procedure to locate said new program.

3. The system of claim 2 wherein said demultiplexer separates a composite bitstream into said elementary bitstreams, said decode timestamps including new decode timestamps, said output timestamps including new output timestamps.

4. The system of claim 3 wherein said input controller instructs said one or more decoders to generate one of said decoded frames when a corresponding one of said new decode timestamps equals a receiver system time clock.

5. The system of claim 4 wherein said one or more decoders store said one of said decoded frames into a buffer memory for said one or more output modules to access.

6. The system of claim 5 wherein said receiver device generates a series of decoded frames, said receiver device subsequently outputting a series of processed frames corresponding to said decoded frames.

7. The system of claim 5 wherein said output controller determines whether said output frame timings of said processed frames are aligned with said new output timestamps.

8. The system of claim 7 wherein said output controller performs said output timing resynchronization procedure to align said output frame timings of said processed frames with said new output timestamps.

9. The system of claim 8 wherein said output controller instructs said one or more output modules to sequentially output one of said processed frames when a corresponding one of said new output timestamps equals a receiver system time clock.

10. The system of claim 9 wherein said receiver device outputs a series of processed frames corresponding to said decoded frames.

11. A method for performing a data synchronization procedure, comprising the steps of:

recovering elementary bitstreams with a demultiplexer that also extracts decode timestamps and output timestamps corresponding to said elementary bitstreams;

decoding said elementary bitstreams with one or more decoders to produce decoded frames;

controlling said one or more decoders according to said decode timestamps by utilizing an input controller;

processing said decoded frames with one or more output modules to produce processed frames; and

controlling said one or more output modules according to said output timestamps by utilizing an output controller that performs an output timing resynchronization procedure to align output frame timings of said processed frames according to said output timestamps, said data synchronization procedure being Performed by a receiver device that receives a multiplexed bitstream from a data source and responsively generates said processed frames to one or more destination devices, said one or more elementary bitstreams including a video bitstream and an audio bitstream, said one or more decoders including a video decoder and an audio decoder, said one or more output modules including a video output module and an audio output module, said output timing resynchronization procedure being performed after receiving new output timestamps as a result of a program change event.

12. A method for performing a data synchronization procedure, comprising the steps of:

recovering elementary bitstreams with a demultiplexer that also extracts decode timestamps and output timestamps corresponding to said elementary bitstreams;

decoding said elementary bitstreams with one or more decoders to produce decoded frames;

controlling said one or more decoders according to said decode timestamps by utilizing an input controller;

processing said decoded frames with one or more output modules to produce processed frames; and

controlling said one or more output modules according to said output timestamps by utilizing an output controller that performs an output timing resynchronization procedure to align output frame timings of said processed frames according to said output timestamps, said data synchronization procedure being performed by a receiver device that receives a multiplexed bitstream from a data source and responsively generates said processed frames to one or more destination devices, said one or more elementary bitstreams including a video bitstream and an audio bitstream, said one or more decoders including a video decoder and an audio decoder, said one or more output modules including a video output module and an audio output module, a system user instructing said receiver device to select a new program, said receiver device responsively performing a program search procedure to locate said new program.

13. The method of claim 12 wherein said demultiplexer separates a composite bitstream into said elementary bitstreams, said decode timestamps including new decode timestamps, said output timestamps including new output time stamps.

14. The method of claim 13 wherein said input controller instructs said one or more decoders to generate one of said decoded frames when a corresponding one of said new decode timestamps equals a receiver system time clock.

15. The method of claim 14 wherein said one or more decoders store said one of said decoded frames into a buffer memory for said one or more output modules to access.

16. The method of claim 15 wherein said receiver device generates a series of decoded frames, said receiver device subsequently outputting a series of processed frames corresponding to said decoded frames.

17. The method of claim 15 wherein said output controller determines whether said output frame timings of said processed frames are aligned with said new output timestamps.

18. The method of claim 17 wherein said output controller performs said output timing resynchronization procedure to align said output frame timings of said processed frames with said new output timestamps.

19. The method of claim 18 wherein said output controller instructs said one or more output modules to sequentially output one of said processed frames when a corresponding one of said new output timestamps equals a receiver system time clock.

20. The method of claim 19 wherein said receiver device outputs a series of processed frames corresponding to said decoded frames.

21. A system for performing a data synchronization procedure, comprising:

means for recovering elementary bitstreams, and extracting decode timestamps and output timestamps corresponding to said elementary bitstreams;

means for decoding said elementary bitstreams to produce decoded frames;

means for controlling said means for decoding according to said decode timestamps;

means for processing said decoded frames to produce processed frames;

means for controlling said means for processing according to said output timestamps; and

means for performing an output timing resynchronization procedure to align output frame timings of said processed frames according to said output timestamps.

22. A method for performing a data synchronization procedure, comprising the steps of:

recovering elementary bitstreams with a demultiplexer that also extracts decode timestamps and output timestamps corresponding to said elementary bitstreams;

decoding said elementary bitstreams with one or more decoders to produce decoded frames;

controlling said one or more decoders according to said decode timestamps by utilizing an input controller;

processing said decoded frames with one or more output modules to produce processed frames; and

controlling said one or more output modules according to said output timestamps by utilizing an output controller that performs an output timing resynchronization procedure to align output frame timings of said processed frames according to said output timestamps, said output timing resynchronization procedure being performed after receiving new output timestamps as a result of a bitstream discontinuity.

23. A method for performing a data synchronization procedure, comprising the steps of:

recovering elementary bitstreams with a demultiplexer that also extracts decode timestamps and output timestamps corresponding to said elementary bitstreams;

decoding said elementary bitstreams with one or more decoders to produce decoded frames;

controlling said one or more decoders according to said decode timestamps by utilizing an input controller;

processing said decoded frames with one or more output modules to produce processed frames; and

controlling said one or more output modules according to said output timestamps by utilizing an output controller that performs an output timing resynchronization procedure to align output frame timings of said processed frames according to said output timestamps, said output timing resynchronization procedure being performed after receiving new output timestamps as a result of a powerup initialization event.