JP3025736B2 - Apparatus for detecting motion in video signals - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motion detecting apparatus for detecting a motion of a video signal such as a television signal using a difference between frames.

[0002]

2. Description of the Related Art A conventional apparatus for detecting a motion in a video signal of this type will be described with reference to FIGS.

A conventional motion detection apparatus for detecting a motion in a video signal connects an input terminal of a frame memory 2 and one input terminal of two subtracters 4 and 5 to a video signal input terminal 1 to which a composite video signal is input. The other input of the subtracter 4 and the input of the frame memory 3 are connected to the output of the frame memory 2 and the other input of the subtracter 5 is connected to the output of the frame memory 3. Connected.

[0004] The output terminal of the subtractor 4 is passed through a low-pass filter 6 for removing the high frequency range of the luminance signal and the color signal.
In order to connect an absolute value circuit 7 for performing an absolute value conversion on the motion component of the luminance low-frequency signal output from the low-pass filter 6 and to extract only the high frequency range of the signal at the output terminal of the subtractor 5 And an absolute value circuit 9 that performs absolute value conversion on the motion components of the luminance high band signal and the color signal output from the high pass filter 8 via the high pass filter 8.

A motion detection circuit 11 for converting an input signal into a motion signal is connected to a maximum value detection circuit 10 for selecting a larger value for each pixel from the outputs of the two absolute value conversion circuits 7 and 9 described above. A motion detection signal output terminal 12 is connected to an output terminal of the motion detection circuit 11.

[0006] The operation of the motion detection device in the video signal having the above-described configuration is as follows. First,
The subtracter 4 calculates the difference between the input video signal and the signal delayed by one frame in the frame memory 2. Here, the signals that are shifted by one frame from the original signal in the color signal have opposite phases, so that the color signal remains in the difference signal.
Therefore, the high-pass and color signals of the luminance signal are removed by the low-pass filter 6 so that the output signal becomes a motion component of the low-luminance signal.

The subtracter 5 calculates the difference between the input video signal and the signal delayed by two frames in the two frame memories 2 and 3. Here, the signals which are shifted by two frames from the original signal in the color signal have the same phase, so that all the difference signals are motion components. Then, only the high band is extracted from the difference signal by the high-pass filter 8 so that the output signal becomes a motion component of the luminance high band signal and the color signal.

The outputs of the low-pass filter 6 and the high-pass filter 8 are subjected to absolute value conversion by the absolute value conversion circuits 7 and 9, respectively. The larger one of the outputs is selected for each pixel and supplied to the motion detection circuit 12. Motion detection circuit 1
8, for example, as shown in FIG. 8, when the input signal is smaller than a certain level, it is regarded as noise and the motion detection signal is output as 0, and as the level of the input signal increases, the motion detection signal is reduced to a maximum value. Increase.

After the motion detection signal output from the motion detection circuit 12 is output from the motion detection signal output terminal 12,
It is supplied to a dimensional Y / C separation circuit (not shown), a scanning line interpolation circuit (not shown), and the like, and is used as a control signal for each circuit.

[0010]

However, in the conventional apparatus for detecting motion in a video signal, if the amount of noise increases to a certain extent, all of the noise is regarded as motion, so that the three-dimensional Y / C separation at a stationary portion is performed. There is a problem that malfunctions easily occur in scanning line interpolation and the like.

When the amount of noise in a still image is considerably increased, a portion having a large amount of noise is processed as a moving image by a three-dimensional Y / C separation or a scanning line interpolation, and a portion with a small amount of noise is processed as a still image. There is a problem that flickering or the like occurs due to the mixture of the moving image processing portion and the still image processing portion, and the image quality is degraded.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it has been proposed to prevent a noise from being erroneously detected as a motion and to suppress a flicker due to a mixture of processing of a still image and a moving image. It is an object of the present invention to provide a motion detection device capable of obtaining image quality.

[0013]

To solve the problems described above SUMMARY OF THE INVENTION The motion detection device in a video signal according to the present gun onset Ming, the motion detector for detecting motion of the image signal by the difference or the like between the frames, the A noise detecting means for detecting noise in the video signal, and a moving picture for the entire screen when the amount of noise detected by the noise detecting means is equal to or more than a certain amount.
Output the motion detection signal at the maximum level
Motion detecting means .

[0014]

[0015]

[Action] In the motion detection device in the gun onset in the video signal according to the light detects noise in the video signal, the noise amount is large
Outputs a motion detection signal that makes the entire screen a moving image
By doing, still image processing part and moving image processing in one screen
Suppresses flicker etc. due to coexistence with parts and is stable
Image quality can be obtained.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the apparatus for detecting a motion in a video signal according to the present invention will be described below with reference to FIGS. 1 to 3. The same parts as those in the conventional example are denoted by the same reference numerals. Is omitted.

The apparatus for detecting motion in a video signal according to the present embodiment includes, in addition to the configuration of the conventional motion detection apparatus described above, a noise detection circuit 13 for detecting noise in a blanking portion of the video signal, and a noise detection circuit. There is provided a noise evaluation circuit 14 for controlling the output of the absolute value conversion circuit 9, that is, the motion signal of the high luminance signal and the color signal, according to the noise level output from 13.

In the above configuration, the noise detection circuit 1
Reference numeral 3 denotes a high-pass filter 15 for extracting a high frequency band of the video signal input from the video signal input terminal 1, and a synchronization pulse or a multiplex signal in a vertical blanking period of the synchronization signal input from the synchronization signal input terminal 16. 2, a gate generating circuit 17 for generating a gate signal in the latter half of the ninth line, as shown in FIG.
And an integration circuit 18 for accumulating and integrating the absolute value of the output signal of the high-pass filter 15 during the period when the gate signal generated at the high level is high.

The noise detection device having the above-described configuration is configured such that the output signal of the high-pass filter 15 is output during the period when the gate signal generated by the gate generation circuit 17 in the second half of the ninth line of the synchronization signal is at the high level. The integrated level of the noise is calculated by accumulating and integrating the absolute value of the above, and when the gate signal goes low, the integration result is supplied to the noise evaluation circuit 14 as the noise level.

Next, the operation of the noise evaluation circuit 14 will be described with reference to FIG. 3. When a threshold value is set according to the supplied noise level and the input motion signal is smaller than the threshold value, Is determined to be due to noise, and the noise evaluation circuit 14 sets the output to 0. That is, when the noise level is high, the threshold is controlled to be large, and when the noise level is low, the threshold is controlled to be low. This can prevent erroneous detection of movement.

Regarding the operation of the noise evaluation circuit 14 in the first embodiment, a function in which the function of the output level with respect to the input level of the motion signal is made variable according to the noise level is described as a second embodiment. This will be described with reference to FIG.

The circuit configuration of this embodiment is the same as that of the first embodiment shown in FIG.
Is the same as that of the embodiment. Here, as shown in FIG. 4, the noise evaluation circuit 14 outputs the ratio of the output level to the input level, that is, the gradient of the graph as α times, according to the noise level supplied from the noise detection circuit 13. When the noise level is high, the value of α is controlled to be small, and when the noise level is low, the value of α is controlled to be large, thereby preventing erroneous detection of noise as motion. Is what you can do.

Although the noise evaluation circuit 14 of the second embodiment shown in FIG. 4 has been described with the relationship between the input level and the output level represented by a linear graph, the output level is generally equal to the input level. Since the function is a function with respect to the level, it is possible to prevent the noise from being erroneously detected as a motion by changing the function according to the noise level. Here, when the function is complicated, the ROM (R
The value to be obtained may be stored in the address at the location of the address using an “only only memory” or the like.

Further, a third embodiment of the apparatus for detecting a motion in a video signal according to the present invention will be described with reference to FIGS. 5 and 6. Omitted.

The apparatus for detecting motion in a video signal according to the present embodiment includes a noise detection circuit 13 for detecting noise in a blanking portion of a video signal in addition to the configuration of the conventional motion detection apparatus described above. The motion detection circuit 11 controls the output signal of the maximum value detection circuit 10 according to the noise level output from the detection circuit 13.

In the above configuration, the noise detection circuit 1
Reference numeral 3 denotes a high-pass filter 15 for extracting a high frequency band of the video signal input from the video signal input terminal 1, and a synchronization pulse or a multiplex signal in a vertical blanking period of the synchronization signal input from the synchronization signal input terminal 16. A gate generation circuit 17 for generating a gate signal in a predetermined portion that is not present, for example, in the latter half of the ninth line, and the high-pass filter 15 during a period in which the gate signal generated by the gate generation circuit 17 is at a high level. And an integration circuit 18 for accumulating and integrating the absolute value of the output signal.

The apparatus for detecting a motion in a video signal configured as described above uses the high-pass filter during the period when the gate signal generated by the gate generation circuit 17 in the second half of the ninth line of the synchronization signal is at the high level. The absolute value of the 15 output signals is cumulatively integrated to calculate the cumulative level of noise. When the gate signal goes low, the result of the integration is supplied to the motion detection circuit 11 as a noise level.

Next, the operation of the motion detection circuit 11 will be described.
Explaining with FIG. 6, when the noise level is smaller than the threshold value, the input signal is converted into a motion detection signal and output as in the above-described conventional example, but when the noise level exceeds the threshold value, Switching is performed so that all motion detection signals are output in the moving image mode. That is, when the amount of noise increases, the motion detection signal is output as the maximum level of motion so that the moving image processing is performed on the entire screen in the subsequent stage, so that the still image processing and the moving image processing are mixed in the still image portion. It is possible to prevent the occurrence of flickering and the like that occur.

[0029]

Motion detection apparatus in the present gun onset in the video signal according to the light according to the present invention is, since the configuration as described above, detects the noise in the video signal, when the noise amount is large,
By outputting a motion detection signal that makes the entire screen a moving image
The still image processing part and the moving image processing part are mixed in one screen
To reduce flickering and obtain stable image quality
Can be

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of an apparatus for detecting motion in a video signal according to the present invention.

FIG. 2 is a timing chart showing gate signal generation timing in the first embodiment of the motion detection apparatus for detecting a motion in a video signal according to the present invention.

FIG. 3 is an input / output characteristic diagram showing an operation of the noise evaluation circuit in the first embodiment of the motion detection apparatus for detecting a motion in a video signal according to the present invention;

FIG. 4 is an input / output characteristic diagram illustrating an operation of a noise evaluation circuit in a second embodiment of the motion detection apparatus for detecting a motion in a video signal according to the present invention.

FIG. 5 is a block diagram showing a third embodiment of the apparatus for detecting motion in a video signal according to the present invention.

FIG. 6 is an input / output characteristic diagram illustrating an operation of a noise detection circuit in a third embodiment of the motion detection apparatus for detecting a motion in a video signal according to the present invention.

FIG. 7 is a block diagram showing a conventional apparatus for detecting motion in a video signal.

FIG. 8 is a diagram showing the relationship between input and output signals of a conventional motion detection circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Video signal input terminal 2 Frame memory 3 Frame memory 4 Subtractor 5 Subtractor 6 Low pass filter 7 Absolute value conversion circuit 8 High pass filter 9 Absolute value conversion circuit 10 Maximum value detection circuit 11 Motion detection circuit 12 Motion detection signal output terminal 13 Noise Detection circuit 14 Noise evaluation circuit 15 High-pass filter 16 Synchronous signal input terminal 17 Gate generation circuit 18 Integration circuit

Claims (1)

(57) [Claims] 1. A motion detecting device for detecting a motion of a video signal based on a difference between frames and the like, wherein: a noise detecting means for detecting noise in the video signal; and a noise amount detected by the noise detecting means is a fixed amount. that's all
, So that video processing is performed on the entire screen,
A motion detection unit that outputs a motion detection signal of a level ;