Patent · US Expired

Conversion of color television signals to or from interlaced form

US4012772A · kind A · utility

5Cited by
1References
6Claims
0Family size

Assignees

Inventors

Key dates

Filing dateSep 9, 1975
Grant dateMar 15, 1977
Priority date
Expiry dateSep 9, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N11/20
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Sequential/interlace scan conversion of NTSC or color television signals is effected by an encoder the output of which is connected to the input of scan conversion apparatus. Controllable phase shift means is included in either the color signal input or the subcarrier input of the encoder and is adapted to vary the phase of the modulated subcarrier for each line of the received color signal by an essentially integral number of quarter cycles in dependence upon the line number. The control is such that the conversion apparatus provides an encoded output signal with the color subcarrier in or NTSC format. The invention can also be used in converting between different types of interlace systems.

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