JPH0638237A - Motion adaptive type three-dimensional y/c separator - Google Patents

Abstract

(57) [Abstract] [Purpose] S / N for noisy composite video signals
The luminance signal and the chrominance signal, which are improved, are separated. [Structure] The S / N level of the input composite video signal is converted to S
The weighting for motion detection (moving image / still image determination) in the motion detection circuit 4 is changed by the microcomputer 7 according to the detected S / N level by the / N detector 8. When the S / N level of the input composite video signal is bad, still image Y / C separation processing is performed to exert a three-dimensional noise reduction effect.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a television receiver,
The present invention relates to a Y / C separation device that is used in a VTR or the like and separates a composite video signal into a luminance signal (Y signal) and a color signal (C signal), and particularly, according to a moving image / still image determination result of an input composite video signal. Motion-adaptive type 3 that applies Y / C separation processing
The present invention relates to a dimension Y / C separation device.

[0002]

2. Description of the Related Art A composite video signal of the NTSC system is used as an input signal to determine a moving image / still image of the input composite video signal, and a moving image Y / C separation processing and a still image Y / C separation are performed according to the determination result. A motion-adaptive three-dimensional Y / C separation device that selects the output of processing and separates this composite video signal into a luminance signal (Y signal) and a color signal (C signal) is built in a television receiver or the like. ing.

FIG. 1 is a block diagram showing the configuration of such a conventional motion adaptive type three-dimensional Y / C separation device. In the figure, 1 is an A / D converter that converts an input analog composite video signal (composite video signal) into a digital signal. The A / D converter 1 converts a converted digital composite video signal into a moving image. It outputs to the Y / C separation circuit 2, the still image Y / C separation circuit 3, and the motion detection circuit 4. The moving picture Y / C separation circuit 2 performs three-dimensional Y / C separation processing on the input composite video signal by frame correlation and outputs the moving picture processed signal to the mixer circuit 5. The still image Y / C separation circuit 3 receives a two-dimensional Y / C for the input composite video signal.
Separation processing is performed, and the still image processing signal is mixed by the mixer circuit 5
Output to. Weighting data for motion detection is input to the motion detection circuit 4 from the microcomputer 7. The motion detection circuit 4, according to the weighting data,
By comparing the input composite video signals between one frame or two frames, it is determined whether the input composite video signal is a moving image or a still image, and the determination result is output to the mixer circuit 5. The mixer circuit 5 includes the motion detection circuit 4
In accordance with the determination result from, the moving image processing signal from the moving image Y / C separation circuit 2 and the still image processing signal from the still image Y / C separation circuit 3 are switched and output to the D / A converter 6. D
The / A converter 6 converts the input digital luminance signal and color signal into an analog luminance signal (Y signal) and color signal (C signal), and outputs these.

Next, the operation will be described. The input analog composite video signal is digitized by the A / D converter 1, and then input to the moving image Y / C separation circuit 2, the still image Y / C separation circuit 3 and the motion detection circuit 4. Video Y / C
In the separation circuit 2, three-dimensional Y / C separation processing is performed by frame correlation, and the separated luminance signal and chrominance signal are output to the mixer circuit 5 as moving image processing signals. On the other hand, the still image Y / C separation circuit 3 performs a two-dimensional Y / C separation process, and the separated luminance signal and chrominance signal are output to the mixer circuit 5 as a still image processing signal. Weighting data for motion detection is externally input to the motion detection circuit 4 via the microcomputer 7, and the input composite video image is compared by comparing the input composite video signals according to the weighting data. It is determined whether the signal is a moving image or a still image, and the determination result is output to the mixer circuit 5. In the mixer circuit 5, the output of the moving image Y / C separation circuit 2 and the output of the still image Y / C separation circuit 3 are selected according to this determination result, and the selected output is analogized by the D / A converter 6. Then, the luminance signal (Y signal) and the chrominance signal (C signal) that have been separated are output.

[0005]

Since the conventional motion adaptive type three-dimensional Y / C separation device is constructed as described above,
Although the S / N of the composite image signal with a lot of noise is improved by performing the still image Y / C separation process,
Since noise is regarded as a moving image portion and moving image Y / C separation processing is performed, there is a problem that S / N cannot be improved.

The present invention has been made in view of the above circumstances, and when a noisy composite video signal is input, the noise is reduced without providing an independent noise reduction means to improve the S / N ratio. It is an object to provide a motion adaptive type three-dimensional Y / C separation device that can be improved.

[0007]

A motion adaptive three-dimensional Y / C separation device according to a first invention of the present application is provided with a means for detecting noise of an input composite video signal, and it is provided with a means for detecting noise of the input composite video signal. It is characterized in that the weighting of the moving image Y / C separation processing and the still image Y / C separation processing is changed.

Motion-adaptive three-dimensional Y according to the second invention of the present application
The / C separation device is a moving image Y / C separation process, a still image Y / C, according to the content of the input composite video signal, the user's preference, etc.
It is characterized in that the weighting of the C separation processing is arbitrarily changed.

[0009]

According to the first aspect of the invention, when the input composite video signal has a lot of noise, the weighting is changed to perform the still image Y / C separation process. In this way, the Y / C separation device itself exerts a three-dimensional noise reduction effect.
Further, in the still image portion, the image quality deterioration is small and the noise reduction effect is large.

In the second invention, since the weighting of the moving image Y / C separation processing and the still image Y / C separation processing can be arbitrarily changed,
The Y / C separation processing is performed according to the type of the input composite video signal or the preference of the user.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings showing the embodiments.

FIG. 2 is a motion adaptive type three-dimensional Y according to the present invention.
It is a block diagram which shows the structure of a / C separation device. 10 in the figure
Is an analog composite video signal (composite video signal)
Is an input terminal for inputting an analog composite video signal through the input terminal 10 and the A / D converter 1 and S.
It is input to the / N detection circuit 8. The A / D converter 1 converts an input analog composite video signal into a digital signal, and converts the converted digital composite video signal into a moving image Y / C.
Separation circuit 2, still image Y / C separation circuit 3, and motion detection circuit 4
And output to. The moving image Y / C separation circuit 2 uses the frame correlation to generate a three-dimensional Y / C for the input composite video signal.
C separation processing is performed, and the video processing signal is processed by the mixer circuit 5
Output to. The still image Y / C separation circuit 3 performs a two-dimensional Y / C separation process on the input composite video signal and outputs the still image processed signal to the mixer circuit 5.

The S / N detection circuit 8 detects noise in the input composite video signal and outputs the detected S / N level to the microcomputer 7. Microcomputer 7
Calculates weighting data for motion detection based on the S / N level and outputs the calculated weighting data to the motion detection circuit 4. The motion detection circuit 4 determines whether the input composite video signal is a moving image or a still image by comparing the input composite video signals between one frame or two frames according to the weighted data, The judgment result is output to the mixer circuit 5. Mixer circuit 5
Is a moving image Y /
The moving image processing signal from the C separation circuit 2 and the still image processing signal from the still image Y / C separation circuit 3 are switched and output to the D / A converter 6. The D / A converter 6 converts the input digital luminance signal and color signal into an analog luminance signal (Y signal) and color signal (C signal), and outputs these.

Next, the operation of the motion adaptive type three-dimensional Y / C separating apparatus of the present invention having such a configuration will be described.

The analog composite video signal input through the input terminal 10 is digitized by the A / D converter 1, and then the moving image Y / C separation circuit 2, the still image Y / C separation circuit 3 and the motion are generated. It is input to the detection circuit 4. Video Y / C separation circuit 2
Then, three-dimensional Y / C separation processing is performed by frame correlation, and the separated luminance signal and color signal are output to the mixer circuit 5 as moving image processing signals. On the other hand, still image Y / C
The separation circuit 3 performs a two-dimensional Y / C separation process, and the separated luminance signal and chrominance signal are output to the mixer circuit 5 as a still image processing signal.

The composite video signal is also input to the S / N detection circuit 8 via the input terminal 10, and the S / N detection circuit 8
The S / N level is detected at. Then, the optimum weighting data is automatically calculated by the microcomputer 7 in accordance with the detected S / N level. In the motion detection circuit 4, according to the weighting data input from the microcomputer 7, it is determined whether the input composite video signal is a moving image or a still image by comparing the input composite video signals. The determination result is output to the mixer circuit 5. In the mixer circuit 5, the output of the moving image Y / C separation circuit 2 and the output of the still image Y / C separation circuit 3 are selected according to this determination result, and the selected output is analogized by the D / A converter 6. Then, the luminance signal (Y signal) and the chrominance signal (C signal) that have been separated are output.

As described above, in the motion adaptive type three-dimensional Y / C separating apparatus of the present invention, the motion detecting circuit 4 operates according to the S / N level of the composite video signal detected by the S / N detecting circuit 8. Since the weighting data for moving image / still image determination is changed, if the S / N of the input composite video signal is bad, the still image Y / C separation process is performed.
A three-dimensional noise reduction effect is exhibited.

In the above embodiment, the weighting data for moving / still image determination is changed based on the S / N level of the composite video signal. However, in the case of UHF and VHF, RF / AGC is used. Based on voltage, in the case of BS C
The weighting data for moving image / still image determination may be changed based on the / N level.

[0019]

As described in detail above, the motion adaptive three-dimensional Y / C separation device of the first invention detects noise in an input composite video signal and detects the motion based on the detected noise amount. Since the weighting of S / N is changed, the three-dimensional noise reduction effect can be exerted on a noisy composite video signal, and the noise is reduced without providing an independent noise reduction means. Can be improved. Further, in the still image portion, the image quality deterioration is small and the noise reduction effect is large.

In the motion adaptive type three-dimensional Y / C separation device of the second invention, the weighting at the time of motion detection can be arbitrarily changed according to the type of the input composite video signal or the preference of the user. A desired Y / C separation process can be performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a conventional motion adaptive three-dimensional Y / C separation device.

FIG. 2 is a block diagram showing a configuration of a motion adaptive three-dimensional Y / C separation device according to the present invention.

[Description of symbols] 1 A / D converter 2 Video Y / C separation circuit 3 Still image Y / C separation circuit 4 Motion detection circuit 5 Mixer circuit 6 D / A converter 7 Microcomputer 8 S / N detection circuit

Claims (2)

[Claims] 1. It is determined whether the input composite video signal is a moving image or a still image, and a moving image Y is determined according to the determination result.
/ C separation processing, still image Y / C separation processing is selected to separate the composite video signal into a luminance signal and a chrominance signal in a motion adaptive three-dimensional Y / C separation device. It has a means for detecting the S / N, and is configured to change the weighting for judging whether the composite video signal is a moving image or a still image based on the detected S / N. A motion adaptive type three-dimensional Y / C separation device. 2. It is determined whether the input composite video signal is a moving image or a still image, and the moving image Y is determined according to the determination result.
/ C separation processing and still image Y / C separation processing are selected to separate the composite video signal into a luminance signal and a chrominance signal. A motion-adaptive three-dimensional Y / C separation device characterized in that the weighting for determining whether it is a still image is variable.