Patent · US Expired

Procedure and device for the automatic correction of skew, of color superimposition, and of image uniformity for television cameras

US5181098A · kind A · utility

26Cited by
6References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 22, 1991
Grant dateJan 19, 1993
Priority date
Expiry dateOct 22, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N23/81
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The device for implementation of the invention procedure, a processor (2) is connected by a data bus (12) to a correction memory (3), a measuring circuit (9), and a digital-to-analog converter (4), and an adder circuit is connected to the output of the digital-to-analog converter (4) and to the output of the scanning circuit of the camera, so as to add to the sawtooth signal supplied by the camera the correction values furnished by the correction memory in synchrony with the scanning of the camera. The correction values result from an evaluation of the position error of the centers of the patterns of an optical grid as restored by the camera and of their equivalents in an electronic grid. Intermediate correction values are computed for each pattern by interpolation of the position errors of the centers of the patterns, using a third-order interpolation polynomial. The invention can be used in high-definition television applications.

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