Audio/video synchronization in a digital transmission system

Patent 5430485 Issued on July 4, 1995. Estimated Expiration Date:

September 30, 2013. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Method and apparatus for preserving or restoring audio to video synchronization
Patent #: 4313135
Issued on: 01/26/1982
Inventor: Cooper

Television compressed audio
Patent #: 4429332
Issued on: 01/31/1984
Inventor: Pargee, Jr.

Audio to video timing equalizer method and apparatus
Patent #: 4703355
Issued on: 10/27/1987
Inventor: Cooper

Method and apparatus for maintaining audio/ video synchronism in a television signal read-out from a digital buffer memory by a reference signal
Patent #: 4851909
Issued on: 07/25/1989
Inventor: Noske , et al.

Audio synchronization apparatus
Patent #: 5202761
Issued on: 04/13/1993
Inventor: Cooper

Video and audio multiplex transmission system Patent #: 5231492
Issued on: 07/27/1993
Inventor: Dangi, et al.

Inventors

Assignee

Thomson Consumer Electronics, Inc.

Application

No. 129974 filed on 09/30/1993

US Classes:

348/423.1, Arrangements for multiplexing one video signal, one or more audio signals, and a synchronizing signal348/515Audio to video

Examiners

Primary: Groody, James J.
Assistant: Lee, Michael G.

Attorney, Agent or Firm

Tripoli; Joseph S., Herrmann; Eric P., Kurdyla; Ronald H.

International Classes

H04N 007/12
H04N 011/02

Abstract

A receiver (FIG. 2 ) for decoding associated compressed video and audio information components transmitted in mutually exclusive "frames" of data with respective time stamps PTSvid and PTSaud respectively, includes a controller (216) which is responsive to the respective received time stamps to provide coarse synchronization by delaying or skipping respective frames of one or the other of the components to approximately time align the two components. Fine synchronization is provided by adjusting the processing or clock frequency (215) of the audio signal processor (212) independent of the video processor (214). The control for the frequency adjustment is related to the difference between audio and video time stamps.