Patent · US Expired

Parabolic mixer for video signals

US6469747B1 · kind B1 · utility

32Cited by
18References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 2, 1999
Grant dateOct 22, 2002
Priority date
Expiry dateSep 2, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/265
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A video signal mixer with a parabolic signal mixing function, especially useful in scene-by-scene color correction systems and “blue screen” video masking applications. The mixer effects mixing two independent signal sources while smoothly controlling the rate of change during mixing. An input stage receives a first video signal and a second video signal. The mixing circuit mixes the first video signal with the second video signal based on a predetermined parabolic function. An aperture signal circuit in the mixer allows a degree of operator control over the parabolic function. An output stage provides a parabolized output signal. The output signal, which comprises the mixture of the first video signal and the second video signal, eliminates discontinuities in regions of the signal which would otherwise produce discontinuities in prior art types of video signal mixers.

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