Patent · US Expired

Method and apparatus for increasing the definiton of an NTSC video signal using an augmentation channel

US4965661A · kind A · utility

3Cited by
30References
22Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 4, 1988
Grant dateOct 23, 1990
Priority date
Expiry dateAug 4, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N11/26
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method for increasing the definition of an NTSC video signal using an augmentation channel involves the generation of both a line summation signal as well as a line difference signal. From the line summation signal, a horizontal detail signal may be derived which may be diagonally filtered and added to a diagonally filtered vertical detail signal and transmitted in a bandwidth of approximately 2.5 mega-hertz. Furthermore, the line summation signal may be applied for the derivation of a standard NTSC video signal which is transmitted separately from the augmentation channel. Decoder apparatus comprises a single digital diagonal filter having complimentary output functions resulting in both improved horizontal and vertical resolution at low cost.

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