JP3526020B2 - Noise reduction device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise reduction device for reducing noise of a video signal and improving S / N in a video signal processing device.

[0002]

2. Description of the Related Art Generally, a video signal is a signal in which image information is repeated at a frame cycle, and the autocorrelation between frames is very strong. On the other hand, since the noise component contained in the video signal generally has no autocorrelation, it is known that when the video signal is temporally averaged for each frame period, only the energy of the signal component becomes low and the noise can be reduced. Has been. For this reason, conventionally, as a frame recursive noise reduction apparatus, a frame recursive noise reduction apparatus that reduces noise based on motion detection information (Japanese Patent Laid-Open No. 6-225178)
No. publication) is known.

FIG. 9 shows a frame recursive noise reduction apparatus based on motion detection information. This is a two-dimensional LPF (low-pass filter) 10 for accurate motion detection.
04, adder 1006, adder 1007, and motion determination circuit 1003
, (1-K) times the multiplier 1001, and K times the multiplier 10
02 and a frame memory 1005.

The motion determination circuit 1003 accurately detects the motion of the input video signal 1000 and removes a noise component, so that the video signal delayed by one frame from the frame memory 1005 and a two-dimensional LPF (low-pass filter) are used. ) 1004
The noise components that have no correlation are removed through the frame to leave a small motion component, a difference from the noise-removed video signal of the previous frame is generated, and if this difference is larger than the threshold value, it is determined to be motion. If it is detected that the motion is large, the motion determination circuit output (K) 10
The value of 11 is decreased (close to 0), and conversely, when the motion is small, the value of the motion determination circuit output (K) 1011 is increased (close to 1).

A motion determination circuit output (K) 1011 indicating the motion of the input video signal 1000 controls the multipliers 1001 and 1002 to control the frame cyclic amount of the video signal, and the input video signal with noise superimposed on it. On the other hand, since motion detection can be performed with high precision, the discomfort due to afterimages is reduced, and the video signal 1000
It is possible to reduce the noise.

Further, a noise reduction device (Japanese Patent Laid-Open No. 6-86104) is known as an area selection type noise reduction device capable of reducing a noise component without blunting an image edge portion without using a frame memory.

In this method, the central pixel and its peripheral pixels are taken in, the difference between the central pixel and its peripheral pixels is calculated, and this difference is compared with a threshold value that serves as a reference for determining whether or not there is a correlation. The pixels that have high correlation are extracted and averaged only with the number of pixels that have a high correlation with the central pixel, so even at the edges of the image, noise can be effectively reduced without blunting, and the pixels are randomly distributed to surrounding pixels. It is also possible to reduce the noise component by replacing the superimposed noise component with the average of highly correlated pixels.

FIG. 10 shows the structure of a conventional area type noise reduction device. In FIG. 10, the input video signal 10000 is directly input to the peripheral pixel capturing circuit 10001. The peripheral pixel capturing circuit 10001 captures the central pixel and its peripheral pixels and inputs them to the absolute value circuits 10002 to 10005.

Absolute value circuits 10002 to 10005 calculate the absolute value of the difference between the central pixel and its peripheral pixels, and the output together with a preset threshold value 100010, and the correlation determination circuit 1000.
6 to 10009, and compares the absolute value with the threshold value 100010. The correlation determination circuits 10006 to 10009 compare the absolute value and the threshold value as follows, and determine the presence or absence of correlation (whether or not it is an edge of an image).

That is, if absolute value ≦ threshold value 100010, there is correlation, and therefore it is not an edge of the image. If absolute value> threshold value 100010, there is no correlation, therefore it is an edge of the image. To do.

In this way, the presence or absence of correlation (whether it is an edge of an image or not) is determined, and the determination result is input to the pixel number counting circuit 100011 and the correlated pixel addition circuit 100012. Further, the pixel number counting circuit 100011 calculates the number of correlated pixels, and outputs the calculation result to the divider 100013. On the other hand, the correlation pixel addition circuit 100012 receives the outputs of the correlation determination circuits 10006 to 10009, adds only the pixels determined to have correlation, and outputs the sum of the correlated pixels to the divider 100013. Divider 100013
Then, the sum of correlated pixels of the correlated pixel addition circuit 100012 output is divided by the number of correlated pixels of the correlated pixel number counting circuit 100012 output to calculate the average value of only the correlated pixels.

By using the output of this divider 100013 to replace the central pixel of the captured pixels, it is possible to generate a video signal with reduced noise components, and to reduce the deterioration of the edges of the image. At the same time, noise components can be reduced.

[0013]

However, such a noise reduction apparatus described in Japanese Patent Laid-Open No. 6-225178 (hereinafter referred to as "motion detection frame cyclic noise reduction apparatus") and Japanese Patent Laid-Open No. Hei. When the noise reduction device described in Japanese Patent Laid-Open No. 6-86104 (hereinafter referred to as “area selection type noise reduction device”) is separately provided in the video signal processing circuit, the noise reduction device is used to hold peripheral pixels. There is a problem that the circuit scale becomes large because two storage means such as a register or a memory are required.

Furthermore, in the noise reduction device (area selection type noise reduction device) described in Japanese Patent Laid-Open No. 6-86104, edge components below the threshold value are regarded as correlated pixels, so that edges Ingredients may be lost.

In a moving subject, even if the edge component of the image is lost to some extent, it does not matter because the edge is originally blunted (unclear). However, if the edge component of the still portion is lost, it may give an uncomfortable feeling, and there is also a problem that the image quality deteriorates.

The present invention has been made in order to solve such a problem, and the motion detection frame recursive noise reduction device and the area selection type noise reduction device can be configured with an optimum configuration without increasing the circuit scale. In addition to realizing it, in the case of still images, noise is mainly reduced by the motion detection frame cyclic noise reduction device, and in the case of moving images, noise is mainly reduced by the area selection type noise reduction device. The present invention provides an optimum noise reduction device according to the movement of an input video signal by controlling the noise reduction device.

[0017]

Noise reduction apparatus according to claim 1, wherein the SUMMARY OF THE INVENTION The present invention includes a motion detection frame recursive type noise reducing apparatus for reducing noise in accordance with the motion component of the video signal,
An area-type noise reduction device that reduces the noise component of the video signal while minimizing the deterioration of the edge component of the image, and a video signal
The AGC device that adjusts the gain and the amount of AGC gain
It has a gain amount calculation means and a gain threshold value control means .

With this configuration, the amount of movement of the video signal and A
Area type noise reduction device according to the gain amount of the GC device
To determine the correlation of peripheral pixels with respect to the center pixel in
AGC device because the threshold for
Even if the gain amount is increased with, the S / N deterioration can be suppressed.
Further, it is possible to perform appropriate noise reduction according to the movement of the input video signal .

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

A noise reducing apparatus according to a second aspect of the present invention is an area type noise reducing apparatus for reducing a noise component of an image signal while reducing deterioration of an edge component of an image as much as possible, and an image reducing apparatus for making an image signal easy to see. Further, it has an AGC device for adjusting the gain of the video signal, a gain amount calculation means for calculating the AGC gain amount, and a gain threshold value control means.

With this configuration, the threshold value for discriminating the correlation between the central pixel and the peripheral pixel in the area type noise reduction device can be controlled according to the gain amount of the AGC device. Even when the amount is increased, appropriate noise reduction can be performed while suppressing the S / N deterioration of the video signal.

[0027]

[0028]

[0029]

[0030]

A noise reducing apparatus according to a third aspect of the present invention is a motion detection frame recursive noise reducing apparatus for reducing noise according to a motion component of a video signal, and deterioration of an edge component of an image as small as possible. Area type noise reduction device for reducing noise component of video signal, and gain adjustment for video signal to make video signal easier to see A
It has a GC device, a gain amount calculating means for calculating an AGC gain amount, and a brightness level detecting means for detecting a brightness level of a video signal.

With this configuration, the amount of movement of the motion detection frame recursive noise reduction device is controlled according to the luminance level of the video signal and the amount of gain of the AGC device, and the peripheral pixels with respect to the central pixel in the area type noise reduction device are controlled. Since it is possible to control the threshold value for discriminating the correlation of S / N, it is possible to improve the S / N deterioration in the case where the gain amount of the AGC device is large and the S / N deterioration of the low luminance part due to gamma correction and the like. Further, it is possible to perform appropriate noise reduction according to the movement of the video signal.

A noise reducing apparatus according to a fourth aspect of the present invention is a motion detection frame recursive noise reducing apparatus for reducing noise according to a motion component of a video signal, and an image while reducing deterioration of edge components of an image as much as possible. Area type noise reduction device that reduces the noise component of the signal, and AG that adjusts the gain of the video signal to make it easier to see
It has a C device, a gain amount calculating means for calculating an AGC gain amount, and a brightness level detecting means for detecting a brightness level of a video signal.

With this structure, the amount of movement of the motion detection frame recursive noise reduction device is controlled according to the luminance level of the video signal, and the area type noise reduction device is controlled according to the luminance level of the video signal and the gain amount of the AGC device. It becomes possible to control the threshold value for discriminating the correlation between the central pixel and the peripheral pixel in. For this reason,
It is possible to improve the S / N deterioration when the gain amount of the AGC device is large and the S / N deterioration of the low luminance part due to gamma correction and the like, and further perform noise reduction according to the movement of the video signal.

A noise reducing apparatus according to a fifth aspect of the present invention is a motion detection frame recursive noise reducing apparatus for reducing noise according to a motion component of a video signal and an image reducing the deterioration of edge components of an image as much as possible. Area type noise reduction device that reduces the noise component of the signal, and AG that adjusts the gain of the video signal to make it easier to see
It has a C device, a gain amount calculating means for calculating an AGC gain amount, and a brightness level detecting means for detecting a brightness level of a video signal.

With this configuration, the amount of movement of the motion detection frame recursive noise reduction device is controlled according to the gain amount of the AGC device, and the area type noise reduction device is controlled according to the gain amount of the AGC device and the luminance level of the video signal. It becomes possible to control the threshold value for discriminating the correlation between the central pixel and the peripheral pixel in. For this reason,
It is possible to improve the S / N deterioration when the gain amount of the AGC device is large and the S / N deterioration of the low luminance part due to gamma correction and the like, and further perform noise reduction according to the movement of the video signal.

[0037]

[0038]

An image processing apparatus according to claim 6 of the present invention is
An image processing apparatus including the noise reduction apparatus according to any one of claims 1 to 5 , and it is possible to configure a highly accurate image processing apparatus in which the influence of a noise component of a video signal is reduced.

An image pickup apparatus according to a seventh aspect of the present invention is an image pickup apparatus including the noise reduction apparatus according to the first to fifth aspects, and has an S / N ratio in which the influence of the noise component of the video signal is reduced. A good and good imaging device can be configured.

An image processing apparatus according to claim 8 of the present invention comprises:
It is an image processing apparatus including the image pickup apparatus according to claim 7 , and a highly accurate image processing apparatus in which the influence of a noise component of a video signal is reduced can be configured.

[0042]

[0043]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1 to 8. The motion detection frame cyclic noise reduction apparatus 1010 follows the conventional noise reduction apparatus of FIG. 9, and the area selection type noise reduction apparatus 1020 has the configuration of the conventional technology of FIG. It follows the noise reduction device.

(First Embodiment) FIG. 1 is a block diagram showing the configuration of a noise reducing apparatus according to the first embodiment of the present invention. The conventional motion detection frame cyclic noise shown in FIG. The motion determining circuit output (K) 1011 is input to the motion detecting means 1009 to the reducing device 1010, the output is output as a control signal of the selector means 1030, and the motion detecting frame circulation is input to the A input of the selector means 1030. The noise reduction device output is inputted, and the B input is inputted with the conventional area selection type noise reduction device 1020 output shown in FIG.

With this configuration, the selector means 1030 can control the output based on the motion detection information of the motion detection frame cyclic noise reduction device 1010.

In this case, the motion detecting means 1040 detects the motion judgment output (K) 1011 as a threshold value which is regarded as motion in advance.
10111 is provided, and when the motion determination circuit output (K) 1011 is larger than this threshold value 10111, the input video signal 100
0 is determined as a still image, and conversely, motion determination output (K) 1011
Is less than the threshold value 10111, the input video signal 1000
Will be determined as a moving image.

When the motion detecting means 1009 determines that it is a moving image, the video signal (A input of the selector means 1030) whose noise has been reduced by the area selection type noise reducing device 1020 is selected by the selector means.
1030 output, in the case of a still image, the motion detection frame cyclic noise reduction device 1010 moves based on the threshold value 10111 so that the noise-reduced video signal (B input of the selector means 1030) becomes the selector means 1030 output. By controlling the output of the detecting means 1009, the output of the selector means 1030 is controlled.

As a result, in the case of a moving image, it is difficult to reduce noise components in a moving image because it is difficult to reduce afterimages when the amount of circulation is increased only with the motion detection frame recursive noise reduction device 1010. However, the noise component can be improved by using the area selection type noise reduction device 1020. In the case of a still image, even if the noise is not reduced by the area selection type noise reduction device 1020, it is possible to sufficiently reduce the noise component by increasing the amount of movement in the motion detection frame recursive noise reduction device 1010. The edge component of the stationary portion can be held without performing signal processing of the mold noise reduction device 1020. Therefore, it is possible to obtain the output video signal 1031 whose noise is appropriately reduced according to the movement of the input video signal 1000.

As for the motion information of the input video signal 1000, the motion detection information in the motion detection frame recursive noise reduction apparatus 1010 is used, so that it is not necessary to newly provide a motion determination circuit, so that the circuit scale is greatly increased. Can be prevented.

Further, the peripheral pixel storage means for the two-dimensional LPF (low pass filter) 1004 of FIG. 9 in the motion detection frame cyclic noise reduction device 1010 and the peripheral pixel capture circuit of FIG. 10 in the area selection type noise reduction device 1020. By sharing the storage means of the peripheral pixels for 10001, the circuit scale can be reduced.

Therefore, it is possible to appropriately reduce the noise included in the video signal regardless of a moving image or a still image without causing an extreme increase in the circuit scale.

If the image pickup apparatus is constructed by using the output video signal 1031, the image pickup apparatus in which the noise component is reduced can be constructed. Even if an image processing apparatus such as image recognition is configured, image processing such as image recognition can be performed on a video signal with a reduced noise component, so that an image with high accuracy such as an improved detection rate of image recognition can be obtained. A processing device can be configured.

(Second Embodiment) FIG. 2 is a block diagram showing the configuration of a noise reducing apparatus according to the second embodiment of the present invention. The noise reducing apparatus shown in the first embodiment is the same as that shown in FIG. On the other hand, multipliers 1040 and 1041, an adder 1042, a weighting means 10121 are provided, and the selector means 1030 and the motion detection means 1009 are deleted. The conventional motion detection frame cyclic noise reduction shown in FIG. The device 1010 is configured to output the motion determination circuit output (K) 1011 to the multiplier (α) 1041 and the multiplier (1-α) 1040, and has the same name and the same number. The means shall have equivalent functions.

The weighting means 10121 weights the motion determination circuit output (K) 1011 in accordance with the motion determination circuit output (K) 1011 to generate a weighted output (α) 10122. For example, weighting output (α) 10122 = {motion detection determination circuit output (K) 1011} ² is performed. When the input video signal 1000 is a moving image, the motion detection determination circuit output (K) 1011 is smaller than that of a still image, so that the moving image is reduced in noise by the area noise reduction device 1020.

As a result, when the input video signal 1000 is a moving image, noise in a moving image that is difficult to reduce is difficult to reduce because the afterimage becomes conspicuous when the amount of circulation is increased only by the motion detection frame cyclic noise reduction device 1010. Even the ingredients
By increasing the weight of the noise reduction processing in the area selection type noise reduction device 1020, the noise component can be reduced appropriately.

Further, when the input video signal 1000 is a still image, noise is reduced by reducing the weight of the noise reduction processing in the area selection type noise reduction apparatus 1020 and increasing the weight of the motion detection frame recursive noise reduction apparatus 1010. It becomes possible to appropriately reduce the components. Therefore input video signal
It is possible to generate the output video signal 1043 in which the noise component included in 1000 is appropriately reduced according to the movement of the video signal.

Regarding the motion information of the input video signal 1000, since the motion detection information in the motion detection frame recursive noise reduction device 1010 is used, it is not necessary to provide a new motion determination circuit, and therefore the circuit scale is greatly increased. Can be prevented.

Further, the peripheral pixel storage means for the two-dimensional LPF (low-pass filter) 1004 of FIG. 9 in the motion detection frame cyclic noise reduction device 1010 and the peripheral pixel capture circuit of FIG. 10 in the area selection type noise reduction device 1020. By sharing the storage means of the peripheral pixels for 10001, the circuit scale can be reduced.

Therefore, it is possible to appropriately reduce the noise contained in the video signal regardless of a moving image or a still image without causing an extreme increase in the circuit scale.

If an image pickup apparatus is constructed using this output video signal 1043, an image pickup apparatus in which noise components are reduced can be constructed. Even if an image processing apparatus is constructed, noise components are reduced in accuracy. A good image processing device can be configured.

(Third Embodiment) FIG. 3 is a block diagram showing the configuration of a noise reducing apparatus according to the third embodiment of the present invention. The noise reducing apparatus shown in the first embodiment is different from that shown in FIG. On the other hand, a motion threshold value control means 1012 is provided, and the motion detection means 1009 and the selector means 1030 are eliminated. The motion detection frame cyclic noise reduction device 1010 shown in FIG. The determination circuit output (K) 1011 is configured to be output to the movement threshold value control means 1012, and other constituent means having the same name and the same number have equivalent functions.

As a result, the motion threshold control means of FIG.
In 1012, based on the motion determination circuit output (K) 1011 including the motion detection information of the input video signal 1000, it is determined whether or not there is a correlation between the peripheral pixel and the central pixel of the area selection type noise reduction device 1020. The threshold value 100010 of the area selection type noise reduction device 1020 shown in FIG.

For example, if the input video signal 1000 is a moving image, the motion detection frame recursive noise reduction device 1010 cannot effectively reduce noise because an afterimage is generated. Therefore, even if the input video signal 1000 is a moving image, afterimages are reduced and noise is reduced. Therefore, when the input video signal 1000 is a moving image, the noise reduction effect of the area selection type noise reduction device 1020 is increased. The threshold value 100010 of the area selection type noise reduction device 1020 shown is increased to control the ratio of pixels having a correlation between the central pixel and the peripheral pixels to be increased.

Thus, the area selection type noise reduction device
Since the central pixel of 1020 is replaced with an average value of only pixels having a correlation, the noise component can be reduced. Further, since the input video signal 1000 is a moving image, even if the sharpness of the edge of the image deteriorates to some extent, there is little discomfort. The motion detection frame recursive noise reduction device 1010 can reduce noise with less discomfort than a conventional noise reduction device in which an afterimage is generated by increasing the amount of circulation.

If the input video signal 1000 is a still image, the threshold value 100010 of the area selection type noise reduction device 1020 shown in FIG. 10 is set so that the motion detection frame cyclic noise reduction device 1010 reduces noise components. Control small. That is, the motion threshold value control means 1012 is controlled so as to reduce the ratio of the pixels having the correlation between the central pixel and the peripheral pixels.

As a result, the area selection type noise reduction device
The central pixel of 1020 is less likely to be replaced by the average value of only the pixels having correlation, so that the rate of edge retention is increased. Further, since the noise component is sufficiently reduced by the motion detection frame cyclic noise reduction device 1010,
It is possible to obtain the output video signal 1021 in which the noise component is appropriately reduced.

Therefore, it is possible to perform optimum noise reduction according to the movement of the input video signal 1000 without causing an extreme increase in the circuit scale.

If the image pickup apparatus is constructed by using this output video signal 1021, it is possible to construct an image pickup apparatus in which the noise component is reduced. Even if the image processing apparatus is constructed, the noise component is reduced in accuracy. A good image processing device can be configured.

(Fourth Embodiment) FIG. 4A is a diagram showing the configuration of a noise reducing apparatus according to the fourth embodiment of the present invention. On the other hand, the AGC device 1050 and the gain amount calculation means 1051 are provided, and the gain threshold value control means 1052 is provided instead of the motion threshold value control means 1012.
The gain amount 10511 calculated by the gain amount calculation means 1051 from the threshold value 100010 of the conventional area selection type noise reduction device 1020 shown in FIG. It is configured to be controlled according to. It should be noted that other constituent elements having the same name and the same number have equivalent functions.

The AGC device 1050 is generally used to apply a gain to the video signal 1000 when the brightness is low to make it easier to see the video in the dark portion. However, when the gain amount of the AGC device 1050 is large, the gain is applied even to the noise component included in the input video signal 1000.
Is easily deteriorated.

Therefore, the threshold value 100010 of the area selection type noise reduction device 1020 for judging whether there is a correlation between the peripheral pixel and the central pixel shown in FIG. 10 is set according to the gain amount 10511 of the output of the AGC device 1050. If controlled, appropriate noise reduction can be performed. That is, first, the AGC device
Gain amount 10511 of 1050 is calculated by gain amount calculating means 1051, and this gain amount 10511 is calculated as gain threshold value controlling means 105.
Output to 2.

Next, in the gain threshold control means 1052,
Based on the motion detection circuit output (K) 1011 and the gain amount 10511 of the AGC device 1050, it is possible to determine whether or not there is a correlation between the peripheral pixel and the central pixel of the area selection type noise reduction device 1020 shown in FIG. Controls the threshold 100010.

The gain threshold control means 1052 determines the peripheral pixels of the area selection type noise reduction device 1020 shown in FIG. 10 according to the gain amount 10511 of the AGC device 1050 and the motion detection circuit output (K) 1011 as follows. The threshold value 100010 for determining whether or not there is a correlation with the center pixel is weighted and controlled. For example, if the gain amount 10511 is large and the video is a threshold value 100
010 = 10 Threshold 1 if the gain amount 10511 is large and the still image
00010 = 6 If the gain amount 10511 is small and the moving image is a threshold value 100
010 = 4 Threshold 1 if the gain amount 10511 is small and still image
Control is performed by giving a weight such as 00010 = 2.

In this way, by controlling the threshold value 100010 of the area selection type noise reduction device 1020 by using the two elements of the gain amount 10511 and the motion detection circuit output (K) 1011, the noise reduction effect is also obtained. You can control. Therefore, since the gain amount of the AGC device 1050 with respect to the input video signal 1000 and the appropriate noise reduction according to the motion amount can be performed, it is possible to obtain an output video signal 1021 with a good S / N with less afterimage.

Here, the gain amount of the AGC device 1050 is set here.
10511 and a motion detection circuit output (K) 1011 for the input video signal 1000, for determining whether or not there is a correlation between the peripheral pixel and the central pixel of the area selection type noise reduction device 1020 shown in FIG. Threshold value 100010 was controlled, but Fig. 4
As shown in (B), by controlling the threshold value 100010 of the area selection type noise reduction device 1020 shown in FIG. 10 only with the gain amount 10511 of the AGC device 1050, an image with good noise reduction of S / N is obtained. You can also get a signal. In that case, the gain threshold value control means 1052
Based on 1, a threshold value 100010 for determining whether or not there is a correlation between the peripheral pixel and the central pixel of the area selection type noise reduction device 1020 shown in FIG.
The threshold value may be controlled by weighting according to 511.
For example, if the gain amount 10511 is large, the threshold value 100010 = 10. If the gain amount 10511 is small, the threshold value 100010 = 2, and the weighting control is performed.

As described above, by using only the gain amount 10511, the threshold value 100010 of the area selection type noise reduction device 1020 is
The noise of the video signal can also be reduced by controlling the.

Therefore, the AGC device for the video signal 1000
Since appropriate noise reduction can be performed according to the gain amount of 1050, an output video signal 1021 having a good S / N with little afterimage can be obtained not only for a normal video signal but also for a video signal at low luminance. be able to.

Therefore, it is possible to perform the optimum noise reduction according to the movement of the input video signal 1000 without increasing the circuit scale extremely.

If the image pickup apparatus is constructed using this output video signal 1021, it is possible to construct an image pickup apparatus in which the noise component is reduced, and even if the image processing apparatus is constructed, the noise component is reduced in accuracy. A good image processing device can be configured.

(Fifth Embodiment) FIG. 5A is a diagram showing the configuration of a noise reduction apparatus according to the fifth embodiment of the present invention, and is shown in FIG. 3 of the third embodiment. The luminance level detecting means 1060 is provided for the noise reducing device, and the motion detecting frame recursive noise reducing device is provided as shown in FIG.
The luminance cyclic amount control means 1070 is provided inside the 1010, and the luminance threshold value control means 1080 is provided instead of the motion threshold value control means 1012. It should be noted that other constituent elements having the same name and the same number have equivalent functions.

In general, a low-luminance video signal is likely to have an S / N deterioration due to the effects of gamma correction, AGC processing and the like. Therefore, first, the brightness level detecting means 1060 detects the brightness level of the input video signal 1000, and the detected brightness level 1061 is used as the brightness threshold value controlling means 1080 and the brightness circulation amount controlling means 10 of FIG.
Output to 70.

The luminance cyclic amount control means 1070 of FIG. 6 controls the cyclic amount (K ′) 10701 according to the motion determination circuit output (K) 1011 of the motion determination circuit 1003 output and the luminance level 1061.

For example, the cyclic amount (K ') 10701 is controlled by weighting as follows. That is, when the still image and the brightness level 1061 are low, the cyclic amount (K ') 10701 = 0.8. When the still image and the brightness level 1061 are high, the cyclic amount (K') 10701 = 0.6 moving image and the brightness level 1061. When the luminance level is low, the amount of circulation (K ') 10701 = 0.4, and when the brightness level 1061 is high, the amount of circulation (K') 10701 = 0.3 (0 ≤ amount of circulation (K ') 10701 ≤ 1) The cyclic amount (K ') 10701 is controlled by giving a weight.

As a result, the motion detection frame recursive noise reduction apparatus 1010 can reduce noise according to the motion determination circuit output (K) 1011 and the brightness level 1061.

In addition, the brightness threshold value control means 1080 uses the area selection type noise reduction device 1020 according to the brightness level 1061.
The threshold value 100010 for determining whether or not there is a correlation between the peripheral pixel and the central pixel shown in FIG. 10 is controlled.

For example, when the brightness level 1061 is low,
Noise is reduced by increasing the proportion of pixels that are considered to be correlated, and when the brightness level 1061 is high, the proportion of pixels that are considered to be correlated is reduced to prioritize image edges over the noise reduction effect. The threshold value 100010 for judging whether or not there is a correlation between the peripheral pixel and the center pixel of the area selection type noise reduction device 1020 shown in FIG. 10 is weighted according to the brightness level 1061 so as to keep it sharp. Control. For example, the threshold value 100010 is controlled as follows. That is, when the brightness level 1061 is low, the threshold value 100010 = 8, and when the brightness level 1061 is high, the threshold value 100010 = 3 is added to control.

As described above, according to the luminance level 1061 of the input video signal 1000 and the output (K) 1011 of the motion determination circuit for the video signal 1000, the cyclic amount (K ′) 10701 of the motion detection frame cyclic noise reduction device 1010. It is possible to obtain a video signal with an improved S / N by further increasing the number of pixels and determine whether or not there is a correlation with the central pixel of the area selection type noise reduction device 1020 shown in FIG. 10 according to the brightness level 1061. By controlling the threshold value 100010 to be controlled, it is possible to prevent the noise component from becoming conspicuous due to the effects of gamma correction processing, AGC, etc. in the case of a dark subject, and further reduce the deterioration of the sharpness of the image edge. You can

As a result, the noise component can be appropriately reduced based on the brightness level 1061 of the input video signal 1000 and the motion determination circuit output (K) 1011, so that the S / N ratio is good while keeping the edges of the image sharp. It is possible to obtain the output video signal 1021 with less afterimage.

Here, the motion detection frame cyclic noise reduction device 1010 and the area selection type noise reduction device 1020 are used.
Although the example in which the control according to the brightness level 1061 is performed for both of them is independent, the output video signal 1021 in which the noise component is reduced can be obtained even if the control according to the brightness level 1061 is independently performed.

For example, as shown in FIG. 5B, a video signal
The noise of the video signal 1000 can also be reduced by controlling only the amount of movement (K ′) 10701 of the moving frame recursive noise reduction means 1010 according to the luminance level 1061 of 1000.

In this case, for example, when the still image and the brightness level 1061 are low, the cyclic amount (K ′) 10701 = 0.9 When the still image is high and the brightness level 1061 is high, the cyclic amount (K ′) 10701. = 0.7 when the video and the brightness level 1061 are low, the amount of tours (K ') 10701 = 0.5 When the video and the brightness level 1061 are high, the amount of tours (K') 10701 = 0.4 (0≤the amount of tours (K ') ) Control is performed by giving a weight such as 10701 ≦ 1).

As a result, the motion detection frame recursive noise reduction device 1010 can reduce noise according to the motion determination circuit output (K) 1011 and the brightness level 1061. Further, noise can be further reduced by the area selection type noise reduction device 1020 with respect to the noise detection device 1010 output of the motion detection frame recursive type noise reduction device. Therefore, in the case of a dark subject, gamma correction processing, AGC, etc. It is possible to prevent the noise component from becoming more conspicuous under the influence of, and it is possible to obtain a good video signal.

Further, as shown in FIG. 5C, only the area selection type noise reduction device 1020 has a threshold value 100010 of the area selection type noise reduction device 1020 shown in FIG. 10 according to the brightness level 1061 of the input video signal 1000. It is also possible to control the output video signal 1021
Can be obtained.

In this case, the brightness threshold value control means 1080
Then, the threshold value 100010 for determining whether or not there is a correlation between the peripheral pixel and the central pixel shown in FIG. 10 of the area selection type noise reduction device 1020 is controlled according to the brightness level 1061.

For example, when the brightness level 1061 is low,
Noise is reduced by increasing the proportion of pixels that are considered to be correlated, and when the brightness level 1061 is high, the proportion of pixels that are considered to be correlated is reduced and the edge of the image is prioritized over the noise reduction effect. The threshold value 100010 for judging whether or not there is a correlation between the peripheral pixel and the center pixel of the area selection type noise reduction device 1020 shown in FIG. 10 is weighted according to the brightness level 1061 so as to keep it sharp. Control. For example, the threshold value 100010 is controlled as follows. That is, when the brightness level 1061 is low, the threshold value 100010 = 9, and when the brightness level 1061 is high, the threshold value 100010 = 3.

Therefore, in the case of a dark subject, it is possible to prevent the noise component from becoming conspicuous due to the effects of gamma correction processing, AGC, etc., and reduce the deterioration of the sharpness of the image edge.

Further, as shown in FIG. 5D, the threshold value 100010 for judging whether or not there is a correlation between the peripheral pixel and the central pixel in the area selection type noise reduction device 1020 of FIG. 10 is moved. Detection frame recursive noise reduction device 10
By controlling according to the motion of the video signal 1000 and the brightness level 1061 using the motion determination circuit output (K) 1011 generated within 10, the S / N ratio is maintained while keeping the edge component of the image sharp.
It is possible to obtain the output video signal 1021 with good afterimage and small afterimage.

In this case, according to the brightness level 1061 and the motion determination circuit output (K) 1011, for example, when the moving image and the brightness level 1061 are low, the threshold value 1000
10 = 7 If the video and the brightness level 1061 are low, the threshold value 1000
10 = 6 If the still image and the brightness level 1061 are high, the threshold value 10
0010 = 3 If the still image and the brightness level 1061 are high, the threshold value 10
Control is performed by weighting such that 0010 = 2.

As described above, by controlling the threshold value 100010 for judging whether or not there is a correlation between the peripheral pixel and the central pixel in the area selection type noise reduction device 1020 of FIG.
Depending on the amount of motion of the video signal 1000 and the brightness level 1061, it is possible to improve that the noise component becomes more noticeable due to the effects of gamma correction processing, AGC, etc. in the case of a dark subject, and the edge component of the image is sharpened in the still image. It is possible to obtain the output video signal 1021 with a good S / N and a small afterimage while maintaining the above.

If an image pickup apparatus is constructed using this output video signal 1021, it is possible to construct an image pickup apparatus in which noise components are reduced, and even if an image processing apparatus is constructed, noise components are reduced in accuracy. A good image processing device can be configured.

(Sixth Embodiment) FIG. 7A is a diagram showing the configuration of a noise reducing apparatus according to a sixth embodiment of the present invention, and FIG. 5A of the fifth embodiment. 8) is provided with an AGC device 1050 and a gain amount calculation means 1051. As shown in FIG. 8, the motion detection frame recursive noise reduction device 1010 also includes a circulation amount control means 1010.
71 is provided, and threshold control means 1090 is further provided instead of the brightness threshold control means 1080, and other constituent means having the same name and the same number have equivalent functions.

In general, a low-luminance video signal is likely to have a poor S / N ratio due to the effects of AGC processing, gamma correction processing, and the like. Therefore, first, the input video signal 1000
The brightness level 1061 of the
In 1051, the gain amount 10511 in the AGC device 1050 is calculated.

The detected brightness level 1061 and gain amount 10
511 is output to the cyclic amount control means 1071 shown in FIG. 8 provided inside the motion detection frame cyclic noise reduction apparatus 1010 shown in FIG.

The cyclic amount control means 1071 in FIG. 8 controls the cyclic amount (K ″) 10711 according to the motion judging circuit output (K) 1011 of the motion judging circuit 1003, the brightness level 1061 and the gain amount 10511.

For example, the cyclic amount (K ″) 10711 is controlled by weighting as follows: That is, when the image is a still image and the luminance level is low and the gain amount is large, the cyclic amount (K ″) 10711 = 0.9 Cyclic amount (K ") 10711 = when the still image is low in luminance level and small in gain amount 0.8 0.8 Cyclic amount (K") 10711 = in still image and in high luminance level and large gain amount 0.7 Cyclic amount (K ") 10711 = 0.6 when the still image is high in luminance level and small in gain amount When the moving image is low and large in gain amount and low in luminance amount, cyclic amount (K") 10711 = 0.5 If the video is a low brightness level and the gain is small, the cyclic amount (K ") is 10711 = 0.4. If the brightness level is high and the gain is large, the cyclic amount (K") is 10711 = 0.3. And when the brightness level is high and the gain amount is small, Cyclic amount (K ") 10711 = 0.2 (0 ≦ cyclic amount (K") 10711 ≦ 1) to have a weight as that controlled.

As a result, in the motion detection frame recursive noise reduction device 1010, the motion determination circuit output (K) 1011, the brightness level 1061, and the AGC device 1050 for the input video signal 1000 are obtained.
It is possible to perform noise reduction using three elements according to the gain amount 10511 of.

Next, in the threshold control means 1090 as well, A
According to the gain amount 10511 of the GC device 1050 and the brightness level 1061, a threshold value 100010 for judging whether or not there is a correlation between the peripheral pixel and the central pixel shown in the area selection type noise reduction device 1020 of FIG. Control.

For example, when the brightness level 1061 is low,
Noise is reduced by increasing the proportion of pixels considered to be correlated, and when the brightness level 1061 is high, the proportion of pixels considered to be correlated is reduced to keep the edges of the image sharper than noise reduction. The weighting is performed as follows, and the threshold value 100010 of the area selection type noise reduction device 1020 is
To control. That is, when the brightness level 1061 is low and the gain amount 10511 is large, the threshold value 100010 = 8. When the brightness level 1061 is low and the gain amount 10511 is small, the threshold value 100010 = 6. The brightness level 1061 is high and the gain amount 10511 is high. Is large, the threshold value 100010 = 3. When the luminance level 1061 is high and the gain amount 10511 is small, the threshold value 100010 = 2 is used for weighting control.

As described above, according to the luminance level 1061 of the input video signal 1000 and the gain amount 10511, the number of cycles (K ″) 10711 of the motion detection frame cyclic noise reduction apparatus 1010 is increased, and the area shown in FIG. Selective noise reduction device
Since the threshold value 100010 of 1020 can be controlled, it is possible to obtain a video signal with a good S / N and a small afterimage according to the movement of the video signal 1000 while keeping the edges of the image sharp.

Here, the motion detection frame recursive noise reduction apparatus 1010 and the area selection type noise reduction apparatus 1020 are used.
Both the brightness level 1061 and the gain amount of the AGC device 1050
An example in which control is performed according to 10511 is shown, but the brightness level 1061 or the gain amount of the AGC device 1050 is 10
Even if control according to 511 is performed, a video signal with a reduced noise component can be obtained.

For example, as shown in FIG. 7B, the cyclic amount control means 1071 of the motion detection frame cyclic noise reduction apparatus 1010 is controlled only by the brightness level.

In this case, the cyclic amount control means 1071 determines the cyclic amount (K ″) 10711 according to the motion judging circuit output (K) 1011 of the motion judging circuit 1003 output and the luminance level 1061 of the video signal as shown in FIG. For example, the cyclic amount (K ″) 10711 is controlled by giving weighting as follows. That is, when the image is a still image and the luminance level is low, the amount of circulation (K ") 10711 = 0.9. When the image is still and the luminance level is high, the amount of circulation (K") 10711 = 0.7. If the value is low, the circulation amount (K ”)
10711 = 0.5 The number of tours (K ") when the video is high and the brightness level is high
Control is performed by giving weighting such as 10711 = 0.3 (0 ≦ circulation amount (K ″) 10711 ≦ 1).

As a result, the motion detection frame recursive noise reduction apparatus 1010 can perform noise reduction using three elements according to the motion determination circuit output (K) 1011 for the video signal 1000 and the brightness level.

Next, also in the threshold control means 1090 of FIG. 7B, according to the gain amount 10511 of the AGC device 1050 and the brightness level 1061, the peripheral pixels shown in the area selection type noise reduction device 1020 of FIG. Controls a threshold value 100010 for determining whether or not there is a correlation with the center pixel.

For example, when the brightness level 1061 is low,
Noise is reduced by increasing the proportion of pixels that are considered to be correlated, and when the brightness level 1061 is high, the proportion of pixels that are considered to be correlated is reduced to keep the edges of the image sharper than noise reduction. As described below, the threshold value 100010 of the area selection type noise reduction device 1020 is controlled by weighting the threshold value 100010. That is, when the brightness level 1061 is low and the gain amount 10511 is large, the threshold value 100010 = 8. When the brightness level 1061 is low and the gain amount 10511 is small, the threshold value 100010 = 6. The brightness level 1061 is high and the gain amount 10511 is high. Is large, the threshold value 100010 = 3. When the luminance level 1061 is high and the gain amount 10511 is small, the threshold value 100010 = 2 is used for weighting control.

As described above, the luminance level of the video signal 1000
Motion detection frame recursive noise reduction device according to 1061
The number of rounds (K ″) 10711 of 1010 is controlled, and the threshold value 100010 of the area selection type noise reduction device 1020 shown in FIG.
By controlling, it is possible to obtain a good video signal according to the movement of the video signal 1000.

Further, as shown in FIG. 7C, an AGC device
The cyclic amount control means 1071 of the motion detection frame cyclic noise reduction apparatus 1010 may be controlled only by the gain amount 10511 of 1050.

In this case, the traveling amount control means 1071 outputs the motion judging circuit output (K) 1011 of the motion judging circuit 1003 and the AGC.
Circulation amount (K ″) 10711 according to gain amount 10511 of device 1050
To control.

Also, the motion detection circuit output 1011 generated inside the motion detection frame cyclic noise reduction apparatus 1010 is output to the threshold value control means 1090. The output of the threshold value control means 1090 controls the threshold value 100010 for judging whether or not there is a correlation with the central pixel of the area selection type noise reduction device 1020. It is possible to obtain a video signal with a good S / N and a small afterimage while keeping the edges sharp.

The threshold control means 1090 controls the output (K) 1011 of the motion judging circuit, the luminance level 1061 of the video signal, and the gain amount 10
The threshold value 100010 of the area selection noise reduction device of FIG. 10 is controlled according to 511. For example, the threshold value 10 of the area type noise reduction means 1020 is weighted as follows.
0010 is controlled. That is, if the moving image is a low luminance level 1061 and the gain amount 10511 is large, the threshold 100010 = 9. If the moving image is a low luminance level 1061 and the gain amount 10511 is small, the threshold 100010 = 8 Threshold value 100010 = 7 when the brightness level 1061 is high and the gain amount 10511 is large. Threshold value 100010 = 6 still when the video level is high and the brightness level 1061 is high and the gain amount 10511 is small. Image, the brightness level 1061 is low, and the gain amount 10511
Is large, the threshold is 100010 = 5, and the brightness level 1061 is low and the gain amount 10511
When is small, the threshold value is 100010 = 4, and the brightness level 1061 is high and the gain amount 10511
Is large, the threshold is 100010 = 3, and the brightness level 1061 is high and the gain amount 10511
When is small, control is performed by giving a weight such as threshold value 100010 = 2.

As a result, the area type noise reduction means 1020
Then, the motion determination circuit output (K) 1011 for the video signal 1000
And brightness level 1061 and AGC device gain amount 10511 3
It is possible to reduce noise according to one factor.

Further, since the cyclic amount (K ″) 10711 of the motion detection frame cyclic noise reduction device 1010 can be controlled according to the gain amount 10511 of the AGC device 1050, S
It is possible to obtain a good video signal of / N.

Further, an area selection type noise reduction device
Instead of the 1020, a plurality of low-pass filters having different characteristics are provided as shown in FIG. 7D, and two elements of the brightness level 1061 of the video signal 1000 and the gain amount 10511 of the AGC device 1050 or one element are set. The noise component of the video signal 1000 can be reduced by controlling the characteristics of the two-dimensional low-pass filter using it.

In this case, as shown in FIG. 7D, a motion detection frame recursive noise reduction device 1010, a two-dimensional LPFA 1022 for noise reduction in a low luminance region, and a two-dimensional LPFB 1023 for noise reduction in a high luminance region are provided. Provided, video signal 1000
Luminance level 1061 and gain amount 10511 of AGC device 2
The threshold control means 1090 is controlled according to one of the factors.

First, the brightness level detecting means 1060 detects the brightness level 1061 of the input video signal 1000, and the gain amount calculating means 1051 calculates the gain amount 10511 in the AGC device 1050. The detected luminance level 1061 and gain amount 10511 are shown in FIG.
It outputs to the circulation amount control means 1071 provided inside.

The cyclic amount control means 1071 in FIG. 8 controls the cyclic amount (K ″) 10711 according to the motion judging circuit output (K) 1011 of the motion judging circuit 1003, the brightness level 1061 and the gain amount 10511.

For example, the cyclic amount (K ″) 10711 is controlled by weighting as follows: That is, when the image is a still image and the luminance level is low and the gain amount is large, the cyclic amount (K ″) 10711. = 0.9 Cyclic amount (K ") 10711 when the still image is low in luminance level and small in gain amount = 0.811 Cyclic amount (K") 10711 when still image is high in luminance level and large in gain amount = 0.7 Cyclic amount (K ") 10711 if the image is a still image and the brightness level is high and the gain amount is small = 0.6. The cyclic amount (K") 10711 = if the image is a video and the luminance level is low and the gain amount is large When the moving image is 0.5 and the brightness level is low and the gain amount is small, the cyclic amount (K ″) 10711 = 0.4 moving image and when the brightness level is high and the gain amount is large, the cyclic amount (K ″) 10711 = 0.3 moving image And the brightness level is high and the gain amount is small, Cyclic amount (K ") 10711 = 0.2 (0 ≦ cyclic amount (K") 10711 ≦ 1) to have a weight and so controlled.

As a result, the motion detection frame recursive noise reduction apparatus 1010 utilizes three elements according to the motion determination circuit output (K) 1011 for the input video signal 1000, the brightness level and the gain amount 10511 of the AGC device 1050. Noise can be reduced.

Next, in this case, the threshold value control means 1090 controls the gain amount 10511 of the AGC device 1050 and the brightness level 106.
Two-dimensional LPFA102 with large noise reduction effect according to 1
Selector means 10 for switching the characteristics of the two-dimensional LPFD 1025 from 2 to give priority to edge retention and has little noise reduction effect
Controlling 26.

For example, the output of the selector means 1026 may be controlled as follows. That is, when the luminance level 1061 is low and the gain amount 10511 is large, when the two-dimensional LPFA1022 luminance level 1061 is low and the gain amount 10511 is small, when the two-dimensional LPFB1023 luminance level 1061 is high and the gain amount 10511 is large, When the luminance level 1061 of the two-dimensional LPFC 1024 is high and the gain amount 10511 is small, the two-dimensional LPFD 1025 is controlled.

The filter coefficient may be adaptively changed by using one low-pass filter whose filter coefficient is variable.

As described above, the luminance level of the video signal 1000
According to 1061 and gain amount 10511, it is possible to control the cyclic amount (K ″) 10711 of the motion detection frame cyclic noise reduction device 1010 and also control the low-pass filters having different characteristics. Therefore, the noise component of the video signal 1000 is reduced. A video signal with a good S / N can be obtained.

The threshold control means 1090 uses the video signal.
Motion determination circuit output (K) 1011 and brightness level for 1000
1061 and the gain amount 10511 of the AGC device reduce noise in accordance with the three elements to further improve the video signal 1000
Since it is possible to select the characteristics of the low-pass filter that are more appropriate for noise reduction in consideration of the motion information of 1., it is possible to obtain the output video signal 1021 that is more appropriately noise reduced.

Further, if the image pickup apparatus is constructed using this output video signal 1021, it is possible to construct the image pickup apparatus in which the noise component is reduced. Even if the image processing apparatus is constructed, the noise component is reduced in accuracy. A good image processing device can be configured.

[0135]

As described in the foregoing, moving according to the present invention
Detection frame cyclic noise reduction device cyclic amount or
The video signal is used to control the threshold of the area selection type noise reduction device.
Signal brightness level or AGC device gain amount
As a result, a large amount of gain is applied to the AGC device when the illuminance is low.
Therefore, video signals with low S / N and low-luminance signals are
Sufficient for signals whose S / N is deteriorated by comma correction
Video signal with low noise and good S / N with little afterimage
You can get the issue.

[0136]

[0137]

Since the output of the area selection type noise reduction device can be controlled by the detection result of the motion detection circuit provided in the motion detection frame cyclic noise reduction device, an increase in circuit scale can be prevented.

[0139]

Further, if it is applied to an image pickup apparatus, not only an image with a good S / N can be picked up, but also it is darker than the conventional image pickup apparatus by controlling by the brightness level of the video signal or the gain amount of the AGC apparatus. It is possible to shoot at a place.

Further, when applied to an image processing apparatus such as image recognition, image processing can be performed with an image having a good S / N, and therefore an effect that a highly accurate processing result can be obtained can be expected.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a noise reduction device according to a first embodiment,

FIG. 2 is a diagram showing a configuration of a noise reduction device according to a second embodiment,

FIG. 3 is a diagram showing a configuration of a noise reduction device according to a third embodiment,

FIG. 4A is a diagram showing a first configuration of a noise reduction device according to a fourth exemplary embodiment; FIG. 4B is a diagram showing a second configuration of the noise reduction device according to the fourth exemplary embodiment;

5A is a diagram showing a first configuration of a noise reduction device according to a fifth exemplary embodiment; FIG. 5B is a diagram showing a second configuration of the noise reduction device according to the fifth exemplary embodiment; ) A diagram showing a third configuration of the noise reduction device of the fifth embodiment, (D) A diagram showing a fourth configuration of the noise reduction device of the fifth embodiment,

FIG. 6 is a diagram showing a configuration of a motion detection frame cyclic noise reduction apparatus according to a fifth embodiment,

7A is a diagram showing a first configuration of a noise reduction device according to a sixth exemplary embodiment; FIG. 7B is a diagram showing a second configuration of the noise reduction device according to the sixth exemplary embodiment; ) A diagram showing a third configuration of the noise reduction device of the sixth exemplary embodiment, (D) A diagram showing a fourth configuration of the noise reduction device of the sixth exemplary embodiment,

FIG. 8 is a diagram showing a configuration of a motion detection frame cyclic noise reduction apparatus according to a sixth embodiment,

FIG. 9 is a diagram showing a configuration of a conventional motion detection frame cyclic noise reduction device,

FIG. 10 is a diagram showing a configuration of a conventional area selection type noise reduction device.

[Explanation of symbols]

1000, 10000 Input video signal 1001, 10011, 100111 Multiplier 1002, 10021, 100211 Multiplier 1003 Motion determination circuit 1004 Two-dimensional LPF (low pass filter) 1005 frame memory 1006, 1007, 1042 adder 1008, 1021, 1031, 1043 Output video signal 1009 Motion detection means 1010 Motion detection frame recursive noise reduction device 1011 Motion judgment circuit output (K) 1012 Motion threshold control means 1020 Area type noise reduction device 1022 Two-dimensional LPF (low pass filter) A 1023 Two-dimensional LPF (low pass filter) B 1024 Two-dimensional LPF (low pass filter) C 1025 Two-dimensional LPF (low pass filter) D 1026, 1030 Selector means 1040, 1041 multiplier 1050 AGC device 1051 Gain amount calculation means 1052 Gain threshold control means 1060 Brightness level detection means 1061 brightness level 1070 Luminance circulation amount control means 1071 Circulation amount control means 1080 brightness threshold control means 1090 threshold control means 10001 peripheral pixel capture circuit 10002 Absolute value circuit 10003 Absolute value circuit 10004 Absolute value circuit 10005 Absolute value circuit 10006 Correlation determination circuit 10007 Correlation determination circuit 10008 Correlation determination circuit 10009 Correlation judgment circuit 10111, 100010 threshold 10121 Weighting means 10122 Weighting control means output (α) 10511 Gain amount 10701 Circulation amount K ' 10711 Patrol amount K ” 100011 Pixel number coefficient circuit 100012 Correlated pixel addition circuit 100013 divider 100014 Output video signal

Continuation of the front page (56) Reference JP-A-4-105467 (JP, A) JP-A-6-121194 (JP, A) JP-A-8-214192 (JP, A) JP-A-8-172551 (JP , A) JP-A-6-86104 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 5/14-5/217

Claims (8)

(57) [Claims] 1. A correlation between a motion detection frame cyclic noise reduction device that reduces a noise component of a static portion without causing an afterimage by changing a cyclic amount according to a motion component of a video signal, and a correlation with surrounding pixels. An area-type noise reduction device that reduces the noise component of the video signal while minimizing the deterioration of the edge component of the image by using the presence or absence of
The video signal includes an AGC device that adjusts the gain of the video signal for easy viewing, a gain amount calculation unit that calculates the AGC gain amount, and a gain threshold value control unit. A noise reduction device for controlling a threshold value for discriminating a correlation between a central pixel and a peripheral pixel in the area type noise reduction device according to the amount of movement of the pixel and the amount of AGC gain. 2. An area type noise reduction device for reducing noise components of an image signal while minimizing deterioration of edge components of an image by utilizing presence / absence of correlation with surrounding pixels, and for making the image signal easy to see. Further, an AGC device that adjusts the gain to the video signal, a gain amount calculation unit that calculates the AGC gain amount, and a gain threshold value control unit are provided, and the gain threshold value control unit determines the area according to the AGC gain amount. Type noise reduction apparatus, wherein a threshold value for determining a correlation between a central pixel and peripheral pixels is controlled. 3. An AGC device for adjusting a gain of a video signal to make the video signal easy to see, a gain amount calculating means for calculating an AGC gain amount, a brightness level detecting means for detecting a brightness level of the video signal, and an image. A motion detection frame cyclic noise reduction device that reduces the noise component of a static part without causing an afterimage by varying the amount of circulation according to the motion component of the signal, and the image using the presence or absence of correlation with surrounding pixels Of the motion detection frame cyclic noise reducing apparatus according to the luminance level of the video signal and the AGC gain amount, the area noise reducing apparatus reducing the noise component of the video signal while reducing the deterioration of the edge component of the video signal. For controlling the number of rounds of the pixel and determining the correlation between the central pixel and the peripheral pixels in the area type noise reduction device. A noise reduction device characterized by controlling a certain value. 4. An AGC device that performs gain adjustment on a video signal to make it easier to see, a gain amount calculation means for calculating an AGC gain amount, a brightness level detection means for detecting a brightness level of the video signal, and an image. A motion detection frame recursive noise device that reduces the noise component of a stationary part without causing an afterimage by varying the amount of recursive motion according to the motion component of the signal, and the presence or absence of correlation with surrounding pixels While minimizing the deterioration of edge components,
An area type noise reduction device for reducing a noise component of a video signal is provided, and the amount of movement of the motion detection frame recursive noise reduction device is controlled according to the luminance level of the video signal, and the luminance level of the video signal and AGC are controlled. A noise reduction device characterized by controlling a threshold value for discriminating a correlation between a central pixel and peripheral pixels in the area type noise reduction device according to a gain amount. 5. An AGC device for adjusting a gain of a video signal to make the video signal easy to see, a gain amount calculating means for calculating an AGC gain amount, a brightness level detecting means for detecting a brightness level of the video signal, and an image. A motion detection frame recursive noise device that reduces the noise component of a stationary part without causing an afterimage by varying the amount of recursive motion according to the motion component of the signal, and the presence or absence of correlation with surrounding pixels While minimizing the deterioration of edge components,
An area-type noise reduction device that reduces the noise component of the video signal is provided, and the amount of movement of the motion detection frame recursive noise reduction device is controlled according to the amount of AGC gain, and also according to the amount of AGC gain and the brightness level. A noise reduction device characterized by controlling a threshold value for discriminating a correlation between a central pixel and a peripheral pixel in the area type noise reduction device. 6. An image processing apparatus comprising the noise reduction device according to any one of claims 1 to 5 . 7. An image pickup device comprising the noise reduction device according to any one of claims 1 to 5 . 8. An image processing apparatus comprising the image pickup apparatus according to claim 7 .