Patent · US Expired

Pure red color detection circuit and color compensation circuit using the same

US6064447A · kind A · utility

2Cited by
13References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 5, 1998
Grant dateMay 16, 2000
Priority date
Expiry dateMar 5, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/68
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Red color saturation is increased and red color with higher purity can be reproduced by composing: a red color detection circuit 1 for detecting a red color signal having higher purity by inputting color differential signals (R-Y) and (B-Y) modulated by color subcarrier, subtracting the absolute value of the (B-Y) signal from the positive polarity component of the (R-Y) signal and removing the negative part of the subtracted signal; Y signal compensation block including: first gain controller 50b for controlling the output signal amplitude of red color detection circuit 1 and a subtracter 50a for subtracting the output signal of first gain controller 50b from a luminance signal Y; an (R-Y) signal compensation block including: second gain controller 51b for controlling the output signal amplitude of red color detection circuit 1 and an adder 51a for adding the output signal of second gain controller 51b and the input (R-Y) signal; and a (B-Y) signal compensation block including: third gain controller 52b for controlling the output signal amplitude of red color detection circuit 1, a polarity inverter 52c for inverting the output signal polarity of third gain controller 52b, a switch…

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