Patent · US Expired

Video signal reproducing apparatus utilizing field memory and delayed sync

US4933774A · kind A · utility

14Cited by
2References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 23, 1988
Grant dateJun 12, 1990
Priority date
Expiry dateAug 23, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/932
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A video signal reproducing apparatus includes a field memory for storing one field of a reproduced video signal, a signal separator for extracting a horizontal sync pulse signal and a vertical sync pulse signal from the reproduced video signal, and an address counter responsive to the horizontal sync pulse signal for addressing the field memory. The apparatus in addition includes a pseudo signal generator and a reset signal generator. The pseudo signal generator is for producing a pseudo vertical sync pulse signal delayed relative to the vertical sync pulse signal. The reset signal generator is connected to the vertical sync pulse separator and the pseudo signal generator for producing a reset signal to reset the address counter. The reset signal generator normally uses the vertical sync pulse signal to produce the reset signal, but uses the pseudo vertical sync pulse signal to produce the reset signal when a vertical sync pulse is not obtained from the vertical sync pulse separator.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.