Patent · US Expired

Phase-increase induced backporch decrease (PIBD) phase recovery method for video signal processing

US6856358B1 · kind B1 · utility

1Cited by
17References
26Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 16, 2002
Grant dateFeb 15, 2005
Priority date
Expiry dateJun 15, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/126
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method to generate an optimum phase shifted sampling clock for sampling a synchronized video signal A(t) having a synchronization signal SYNC pulse is achieved. The method comprises, first, generating a sampling clock having a first edge aligned with a trailing edge of the SYNC pulse. The sampling clock period comprises the SYNC pulse period divided by M. Second, the number of sampling clock cycles N is counted from the trailing edge of the SYNC pulse until the A(t) value at the first edge of the sampling clock exceeds a minimum value. Third, the sampling clock and the SYNC pulse are phase shifted forward until the A(t) value at the first edge of the sampling clock first exceeds a minimum value on clock cycle N−1 to thereby establish a worst case phase shift of the sampling clock. Finally, A(t) is sampled at an offset from the worst case phase shift to thereby generate an optimum phase shifted sampling clock.

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