Title:
DC COMPONENT RECOVERY DEVICE
Document Type and Number:
Japanese Patent JP3305668
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a DC component recovery device that provides an always proper DC component to a black level of a video signal by avoiding the effects of a high-frequency noise mixed in a video signal onto a black level due to the effects of external disturbance.
SOLUTION: This DC component recovery device, employing a feedback clamp circuit or the like, provides a DC component to the black level of an analog video signal whose level is deviated from a pedestal level due to loss of the DC component, so as to restore the black level to the pedestal level. The feedback clamp circuit is provided with a differential amplifier 11 that amplifies the difference between a correction level for a given black level and a received analog video signal and provides the output of a difference signal and averaging circuits 13-17 that average the difference signal for a prescribed period to provide the output of a correction level, in response to a timing signal.
Inventors:
Yoji Urayama
Application Number:
JP32951098A
Publication Date:
July 24, 2002
Filing Date:
November 19, 1998
Export Citation:
Assignee:
NEC
International Classes:
H04N5/18; (IPC1-7): H04N5/18
Domestic Patent References:
| JP4160819A | ||||
| JP738777A | ||||
| JP6379477A | ||||
| JP9121297A | ||||
| JP63176069A | ||||
| JP686095A |
Attorney, Agent or Firm:
Kiyoshi Inagaki
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