Synchronization of digital audio with digital video

Patent 5351092 Issued on September 27, 1994. Estimated Expiration Date:

July 23, 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

Signal multiplexing system
Patent #: 4233627
Issued on: 11/11/1980
Inventor: Sugihara

Compressed audio silencing
Patent #: 4825303
Issued on: 04/25/1989
Inventor: Yablonski , et al.

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.

Method of providing identification, other digital data and multiple audio tracks in video systems
Patent #: 4855827
Issued on: 08/08/1989
Inventor: Best

Rotary head type recording/reproducing method and apparatus for recording and reproducing a digital audio signal
Patent #: 4928185
Issued on: 05/22/1990
Inventor: Kobayashi, et al.

Method and apparatus for PCM recording and reproducing an audio signal having an asynchronous relation between the sampling frequency for the audio signal and the rotation frequency of a rotary head scanner
Patent #: 4937686
Issued on: 06/26/1990
Inventor: Arai, et al.

Digital signal recording apparatus
Patent #: 4953168
Issued on: 08/28/1990
Inventor: Odaka

System for recording and reproducing digital audio signal
Patent #: 5043830
Issued on: 08/27/1991
Inventor:

Digital signal recording apparatus time-division multiplexing video and audio signals Patent #: 5101274
Issued on: 03/31/1992
Inventor: Yoshimura, et al.

Inventors

Assignee

The Grass Valley Group, Inc.

Application

No. 096356 filed on 07/23/1993

US Classes:

348/512, Locking of video or audio to reference timebase348/515, Audio to video386/104Digital audio signal

Examiners

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

Attorney, Agent or Firm

Gray; Francis I.

International Class

H04N 005/04

Abstract

A method for synchronization of a digital audio signal sampled at a standard audio frequency with the corresponding digital video signal sampled at a standard video frequency associates an integer number of samples of the digital audio signal with each video field of the digital video signal. The number of audio samples per video field is determined by the audio sample rate rounded up to the nearest integer. Every N video fields where the number of digital audio samples is an integer value, the digital audio signal is resynchronized with the digital video signal by repeating the digital audio samples at the end of video field N that correspond to video field N+1. At reception the same digital audio samples are skipped at the end of video field N.