JPH0324775U

JPH0324775U -

Info

Publication number: JPH0324775U
Application number: JP8584089U
Authority: JP
Priority date: 1989-07-21
Filing date: 1989-07-21
Publication date: 1991-03-14

Description

[Brief explanation of drawings]

第１図は本考案のノイズリダクシヨンの一実施
例を示すブロツク線図、第２図は同第１図の帰還
回路２の一実施例を示すスイツチ回路図、第３図
は同第１図の動作波形図、第４図は従来のノイズ
リダクシヨンのブロツク線図、第５図は同第４図
の動作波形図である。２，４……帰還回路、３……１Ｈ遅延線、５，
６，１０……加算器、７……エンフアシス回路、
８……リミツタ回路、１１……ライン非相関検出
回路、１６……スイツチ素子、Ｂ……ライン非相
関パルス信号である。 FIG. 1 is a block diagram showing an embodiment of the noise reduction of the present invention, FIG. 2 is a switch circuit diagram showing an embodiment of the feedback circuit 2 shown in FIG. 1, and FIG. 3 is a switch circuit diagram showing an embodiment of the feedback circuit 2 shown in FIG. FIG. 4 is a block diagram of conventional noise reduction, and FIG. 5 is an operation waveform diagram of FIG. 4. 2, 4... Feedback circuit, 3... 1H delay line, 5,
6, 10...adder, 7...emphasis circuit,
8... Limiter circuit, 11... Line non-correlation detection circuit, 16... Switch element, B... Line non-correlation pulse signal.

Claims

[Scope of utility model registration request]

In a noise reduction circuit for line-correlated color signals, the input terminals are connected to a first adder input, a second adder input, and a third adder input, respectively, and the output terminals of the first adder and the third adder input are connected to each other. and the other inputs of the first adder are respectively connected to a 1H (horizontal scanning period) delay line and a first feedback circuit output, and the 1H delay line output and the first feedback circuit input are connected, The other input of the second adder and the output of the second adder are connected to a second feedback circuit output and an emphasis circuit input, respectively, and the second feedback circuit input and the 1H delay line output are connected to each other. , the output of the emphasis circuit is connected to a limiter circuit, the output of the limiter circuit is connected to a terminal of a changeover switch, the other terminal of the switch is grounded, and the common terminal of the switch is connected to the third addition circuit. The line decorrelation detection circuit output is connected to the first feedback circuit and the same switch, and the output of the first feedback circuit is connected to the third adder output terminal at the time of line decorrelation. Noise reduction that changes the feedback rate to reduce color blur in the lower part of the image.