Patent · US Expired

Circuit apparatus for automatic correction of TV color balance

US5040054A · kind A · utility

9Cited by

2References

8Claims

0Family size

Assignee

BTS Broadcast Television Systems GmbH · DE

Inventors

Dieter Schmidt · Steinhagen, DE
Peter Bachmann · Ottobrunn, DE

Key dates

Filing date	Jul 20, 1990
Grant date	Aug 13, 1991
Priority date	—
Expiry date	Jul 20, 2010

Classification

Technology area (CPC H)Electricity
CPC primaryH04N9/73
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

For picture elements (pixels) having a luminance value in a mid-range of luminance magnitude and a color saturation smaller than a predetermined threshold value a correction signal is obtained by integration of the color saturation value followed by multiplication by the difference between an actual luminance signal and a gradation distorted luminance signal. Threshold values at the boundaries of the mid-range of the luminance signal are determined in a manner dependent upon the extreme values that appear from time to time in the luminance signal. The stored maximum and minimum values of the luminance signals are respectively decremented and incremented at frame intervals until replaced by a new maximum or minimum value establishing a new maximum or minimum.

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