JPS5939575U

JPS5939575U - noise reduction circuit

Info

Publication number: JPS5939575U
Application number: JP13374582U
Authority: JP
Inventors: 成田　隆人
Original assignee: ソニー株式会社
Priority date: 1982-09-02
Filing date: 1982-09-02
Publication date: 1984-03-13

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

第１図は従来のノイズリダクション回路を示すブロック
図、第２図はその各部の信号を示す信号波形図、第３図
は本考案によるノイズリダクション回路の一実施例を示
すブロック図、第４図はその各部の信号を示す信号波形
図である。１・・・ノイズリダクション回路、２・・・バイパスフ
ィルタ、３・・・ノイズ抽出回路、４・・・リミッタ、
５゛・・・遅延回路、６・・・減算回路、７・・・位相
進め回路、１１・・・大振幅波形部補正回路、１２・・
・バイパスフィルタ、１３・・・リミッタ、１４・・・
レベル調整回路、１５・・・減算回路。Fig. 1 is a block diagram showing a conventional noise reduction circuit, Fig. 2 is a signal waveform diagram showing signals of each part thereof, Fig. 3 is a block diagram showing an embodiment of the noise reduction circuit according to the present invention, Fig. 4 is a signal waveform diagram showing signals of each part. 1... Noise reduction circuit, 2... Bypass filter, 3... Noise extraction circuit, 4... Limiter,
5... Delay circuit, 6... Subtraction circuit, 7... Phase advance circuit, 11... Large amplitude waveform part correction circuit, 12...
・Bypass filter, 13...Limiter, 14...
Level adjustment circuit, 15... subtraction circuit.

Claims

[Scope of utility model registration request]

A video signal is sequentially passed through a first bypass filter and a first limiter to obtain an extracted noise signal including a large amplitude waveform portion, and a first subtraction circuit that receives this extracted noise signal as a subtraction input extracts the extracted noise signal from the video signal. a second bypass filter that receives the video signal and has a cutoff frequency lower than the cutoff frequency of the first bypass filter; and an amplitude limiting characteristic that receives the output of the second bypass filter and makes the rise time of the large amplitude waveform part contained in the output almost equal to the rise time width of the corresponding large amplitude waveform part of the extracted noise signal. a second limiter having a second limiter, and receiving an output of the second limiter so as to make the amplitude value of a large amplitude waveform portion included in the output approximately equal to the amplitude value of the corresponding large amplitude waveform portion of the extracted noise signal. a level adjustment circuit that suppresses the output level of the noise signal; and a second subtraction circuit that subtracts the output of the level adjustment circuit from the extracted noise signal and sends the subtraction output as the subtraction input to the first subtraction circuit. A noise reduction circuit characterized by comprising: