System and method for providing picture-in-picture timebase management

• US 7,230,652 B2
• Filed: 04/08/2005
• Issued: 06/12/2007
• Est. Priority Date: 03/01/2002
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Kellerman, Marcus, Chen, Sherman (Xuemin), Demas, Jason
• Primary Examiner(s): NATNAEL, PAULOS M
• Application Number:
  US11/101,997
• Publication Number:
  US 20050175322A1
• Time in Patent Office: 795 Days
• Field of Search: 348563-569, 348/500, 348510-515, 348/584, 348/588
• US Class Current: 348/512
• CPC Class Codes: H04N 21/4147 PVR [Personal Video Recorder] H04N5/76 takes precedence ; arrangements for broadcast with accumulation-type receivers H04H20/40
• 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 21/4341 Demultiplexing of audio and video streams
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream
• CPC Class Codes: H04N 5/76 Television signal recording
• CPC Class Codes: H04N 5/783 Adaptations for reproducing at a rate different from the recording rate
• CPC Class Codes: H04N 9/79 Processing of colour television signals in connection with recording
• CPC Class Codes: H04N 9/7921 for more than one processing mode

Abstract

Systems and methods that provide picture-in-picture timebase management are provided. In one example, a method may include the steps of sending a first video signal and a second video signal to a video decoder; sending a first audio signal to the audio decoder, the first audio signal being associated with the first video signal; locking a single timing mechanism to program clock references (PCRs) of the first audio signal; and decoding the first audio signal and the first video signal according to a timebase of the single timing mechanism.

Claims

1. A method for providing picture-in-picture operation, the method comprising:

sending a first video signal and a second video signal to a video decoder;

sending a first audio signal to an audio decoder, the first audio signal being associated with the first video signal;

locking a single timing mechanism to program clock references (PCRs) of the first audio signal; and

decoding the first audio signal and the first video signal according to a timebase of the single timing mechanism.

2. The method of claim 1, further comprising displaying the first video signal and the second video signal on a single display device.

3. The method of claim 1, further comprising decoding the second video signal according to the timebase of the single timing mechanism.

4. The method of claim 1, further comprising decoding the second video signal asynchronously with respect to the timebase of the single timing mechanism.

5. The method of claim 1, further comprising decoding the second video signal synchronized to a vertical synch signal of the second video signal.

6. The method of claim 1, further comprising decoding the second video signal without timebase management.

7. The method of claim 1, further comprising dropping or repeating frames in the second video signal to avoid overflowing or underflowing a second video signal buffer.

8. The method of claim 1, further comprising operating the video decoder and the audio decoder in a timebase management mode.

9. The method of claim 1, further comprising sending at least a third video signal to the video decoder while sending the first and second video signals to the video decoder.

10. The method of claim 1, wherein sending the first video signal and the second video signal comprises concurrently sending the first video signal and the second video signal to the video decoder.

11. The method of claim 1, wherein the single timing mechanism comprises a single voltage controlled crystal oscillator (VCXO).

12. The method of claim 1, wherein the single timing mechanism comprises a single crystal.

13. The method of claim 1, wherein the single timing mechanism comprises an approximately 27 MHz timebase.

14. The method of claim 1, wherein the picture-in-picture operation is provided in a personal video recording system.

15. The method of claim 1, wherein the sending, locking and decoding steps are performed in a head end portion of a video communication system.

16. The method of claim 1, wherein the sending, locking and decoding steps are performed in a head end portion of a video-on-demand server.

17. A method for providing picture-in-picture operation, the method comprising:

sending a first video signal and a second video signal to a video decoder;

sending a first audio signal to an audio decoder, the first audio signal being associated with the first video signal;

controlling a single timing mechanism based on program clock references (PCRs) of the first audio signal; and

decoding the first audio signal and the first video signal according to a timebase of the single timing mechanism.

18. The method of claim 17, wherein controlling a single timing mechanism based on PCRs of the first audio signal comprises controlling the single timing mechanism based on difference between the PCRs of the first audio signal and another timing reference.

19. The method of claim 17, wherein controlling a single timing mechanism based on PCRs of the first audio signal comprises programming a frequency of a variable oscillator as a function of the PCRs of the first audio signal.

20. The method of claim 17, wherein controlling a single timing mechanism based on PCRs of the first audio signal comprises controlling a variable oscillator as a function of an error between at least one of the PCRs of the first audio signal and a current audio system time clock.