JP3426139B2 - Video signal processing method and apparatus, and imaging apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal processing method for processing a video signal picked up by an image pickup device, an apparatus therefor, and an image pickup apparatus using the same, and more particularly to a video signal having a wide dynamic range with a small noise component. The present invention relates to technology that enables synthesis.

[0002]

2. Description of the Related Art In recent years, solid-state image pickup devices such as CCD image pickup devices have been widely used as image capturing means for video cameras, electronic still cameras and the like. However,
The dynamic range of this solid-state image sensor is narrower than that of silver halide photography, and when imaging a subject with a large contrast ratio, bright areas are uniformly whitish, so-called white crushing and dark areas are uniformly blackish. That is, the so-called black shadow occurs, and the image quality is significantly deteriorated.

Conventionally, a technique described in Japanese Patent Application Laid-Open No. 7-131718 is known as a means for expanding the dynamic range of a video signal. This is to take a plurality of images with different exposures in the same scene, and to combine non-standard exposure video signals and standard exposure video signals by providing a common combining area for the video signals with different exposures. Thus, a video signal with an expanded dynamic range is obtained.
A conventional signal processing apparatus for expanding the dynamic range of a video signal will be described below with reference to FIGS. 10 to 15.

FIG. 10 shows the configuration of a conventional signal processing apparatus for expanding the dynamic range of a video signal, and here shows the case of dynamic range expansion processing in frame units. In FIG. 10, reference numeral 1010 denotes an image sensor, which alternately outputs two types of video signals, a standard exposure time and a non-standard exposure time, in frame units. Reference numeral 1020 denotes an image pickup device driving means, which drives the image pickup device 1010 and
As shown in (A), an exposure time identification signal 1021 indicating the exposure time is output during standard exposure and non-standard exposure. 103
Reference numeral 0 denotes a preprocessing unit 1030 that processes an output signal from the image sensor 1010. The pre-processing means 1030 performs CDS means for removing the noise component of the analog signal output from the image sensor by correlated double sampling, and amplitude adjustment so that the analog video signal from which the noise component is removed maintains a constant signal level. It is composed of an AGC means and a clamp circuit for clamping the analog video signal whose amplitude has been adjusted for A / D conversion.

Reference numeral 1040 is an A / D converter for converting the output of the preprocessing means 1030 into a digital video signal.
Reference numeral 50 is a synchronization means. The synchronization means 1050 is shown in FIG.
2, memory means 10511 for delaying the video signal for one frame, selector means 10513,
And selector means 10514. So A
The D / D converter output 1041 is given to the memory means 10511 and the selector means 10513, and at the same time, the memory means 10513 outputs video signals with different exposure times which are alternately output for each frame as shown in FIG.
After delaying by one frame as shown in (B), the memory means output 10512 is given to the selector means 10514 and the selector means 10513 and switched by the exposure time identification signal 1021 in FIG. 13 (C). As shown in E), the selector means 10514 is divided into two systems so that the output is always the non-standard exposure video signal 1070 and the selector means 10513 is always the standard exposure video signal 1060, and output at the same timing. To do.

Reference numeral 1080 denotes a video signal synthesizing means, which synthesizes the standard exposure video signal 1060 and the non-standard exposure video signal 1070 according to the signal level to generate a synthetic video signal 1081. 1090 is for the composite video signal 1081
The camera process 1090 performs gamma correction, contour correction, and the like.

14 and 15 show a video signal synthesizing means 1
The synthesis of the non-standard exposure video signal 1070 and the standard exposure video signal 1060 at 080 will be described. 14 and 15
, The standard exposure video signal 1060 has a longer exposure time than the non-standard exposure video signal 1070, and therefore the LONG and the non-standard exposure video signal 1070 have a shorter exposure time.
I will call it HORT.

FIG. 14A shows the input / output characteristics of the LONG. When the amount of incident light exceeds the amount of saturated light, the output of LONG is saturated at a constant value, and white crushing is likely to occur. However, a normal standard video signal can be obtained up to the saturated light amount. 14
(B) is an input / output characteristic of SHORT. SHORT
Can shorten the shutter time as compared with standard exposure or lower the sensitivity as compared with LONG to increase the amount of incident light that saturates the image sensor by that amount. However, SH
The portion of the ORT where the amount of incident light is small has a poor S / N ratio and is easily blacked out. Therefore, the dynamic range of the video signal is expanded by utilizing these two characteristics. For example, in a region where LONG is not saturated, only LONG is output, and in a region where LONG starts to be saturated (MIX region), LONG and SHO are output.
A value obtained by internally dividing RT by K (video signal synthesis signal) is output, and in a region where LONG is completely saturated, control is performed so that only SHORT is output.

The composite video signal 1081 is set to OUT, and MI
Let Yth be the start level of the X region and SAT be the saturation level of the LONG, and let LSET and SHORT intersect in the MIX region to make OFSET1 and K offset values for smoothly synthesizing the video signals as video signal synthesis control signals. . K is LONG at the lower limit and SH at the upper limit of the MIX area
This is a control signal for smoothly varying so as to be ORT.

First, FIG. 14C shows SHORT + OFS.
ET1 is shown, FIG. 15 (D) shows how the video signals are combined by the above control, FIG. 15 (E) shows the characteristics of K (video signal combining control signal), and FIG. A synthetic video signal 1081 obtained as a result is shown. The above control is expressed by the following equations. LONG ≦ Yth (LONG is not saturated, K = 0) OUT = LONG Yth ≦ LONG ≦ SAT (MIX region, 0
≦ K ≦ 1) OUT = (1−K) × LONG + K × (SHORT + O
FSET1) where K = (LONG-Yth) / (SAT-Yt
h) When LONG ≧ SAT (region where LONG is saturated, K = 1) OUT = SHORT + OFSET1 Conventionally, the video signals are synthesized in this way to obtain a video signal with a high dynamic range.

[0011]

However, since the standard exposure video signal and the non-standard exposure video signal have different characteristics of the image sensor output with respect to the amount of incident light, the non-standard exposure video can be obtained only by the synthesis of the above video signal synthesizing means. The signal had a characteristic that the S / N was deteriorated as compared with the standard exposure video signal. Therefore, the combined video signal obtained by synthesizing the standard exposure video signal and the non-standard exposure video signal uses only the standard exposure video signal (LONG) in the area where the standard exposure video signal is not saturated, but the S / N does not matter. , An area where the ratio of the non-standard exposure video signal (SHORT) gradually increases from the standard exposure video signal (from the MIX area to the SHO
There is a problem that the S / N is deteriorated in the region where the RT region starts). Further, since the offset value is added to the non-standard exposure video signal, there is a problem that the noise component is easily noticeable.

The present invention solves the above problems and provides a video signal processing method and apparatus capable of generating a good video signal having a wide dynamic range with little S / N deterioration, and further providing such a video signal. An object of the present invention is to provide an image pickup device capable of displaying a good image having a high dynamic range by signal processing.

[0013]

According to the present invention, in order to achieve the above object, a standard exposure video signal shot at a standard exposure time and an exposure time shorter than the standard exposure time are shot for the same scene. generating a non-standard exposure image signal, the video signal processing method and apparatus for synthesizing a video signal whose dynamic range is expanded by using these, movies standard exposure
Image signal and non-standard exposure video signal are combined according to signal level
The composite video signal
Depending on the ratio of the semi-exposure video signal and the non-standard exposure video signal,
The above-mentioned configuration suppresses deterioration of resolution while improving S / N.
A high dynamic range video signal can be obtained. Also,
By performing the image signal processing as described above, the resolution degradation
Good dynamic range with improved S / N
It is possible to obtain an image pickup device of a camera.

[0014]

[0015]

[0016]

[0017]

DETAILED DESCRIPTION OF THE INVENTION The invention of claim 1, wherein the present invention,
A standard exposure video signal shot with a standard exposure time and a non-standard exposure video signal shot with an exposure time shorter than the standard are generated for the same scene, and the dynamic range is expanded using these signals. In a video signal processing method for synthesizing a signal, a standard exposure video signal included in the synthetic video signal and a non-standard exposure video signal which are non-standard exposure video signals and non-standard exposure video signals are synthesized according to a signal level. A video signal processing method characterized by removing a noise component according to the ratio of a standard exposure video signal, and having an effect of removing a noise component of a composite video signal and improving S / N.

According to the second aspect of the present invention, the noise component is removed according to the ratio of the non-standard exposure video signal in a large proportion, and the noise component is removed in the ratio of the standard exposure video signal in a large proportion. depending on a video signal processing method according to claim 1, wherein a is not performed to remove noise components, and removes a noise component of the composite video signal has the effect of improving the S / N.

According to a third aspect of the present invention, a standard exposure video signal shot with a standard exposure time and a non-standard exposure video signal shot with a shorter exposure time than the standard are provided for the same scene. In a video signal processing device having a video signal synthesizing unit for synthesizing and synthesizing a video signal whose dynamic range has been expanded using these, the standard exposure video signal and the non-standard exposure video signal are synthesized according to a signal level. A video signal comprising a noise removing means for removing a noise component from the composite video signal according to the ratio of the standard exposure video signal and the non-standard exposure video signal included in the composite video signal. This is a processing device, and has an effect of removing noise components of the combined video signal and improving S / N.

In the invention according to claim 4 of the present invention, the noise removing means includes a digital filter for passing the composite video signal and a weighting means, and in a portion where the ratio of the non-standard exposure video signal is large in the composite video signal. The weighting means is controlled by the video signal synthesis control signal from the video signal synthesis means so that the digital filter is passed in accordance with the proportion and the digital filter is not passed in the portion where the standard exposure video signal is large according to the proportion. The video signal processing device according to claim 3, wherein the video signal processing device has a function of removing a noise component of the composite video signal and improving S / N.

According to a fifth aspect of the present invention, a standard exposure video signal shot with a standard exposure time and a non-standard exposure video signal shot with a shorter exposure time than the standard are provided for the same scene. In a video signal processing method for generating and synthesizing a video signal whose dynamic range has been expanded using these, a standard video image signal and a non-standard video image signal are combined into a composite video signal according to a video signal level. On the other hand, a video signal processing method characterized by removing a noise component according to a ratio of a standard exposure video signal and a non-standard exposure video signal included in the composite video signal and a signal level of the composite video signal, It has the effect of removing the noise component of the composite video signal and improving the S / N.

According to a sixth aspect of the present invention, a standard exposure image signal photographed at a standard exposure time and a non-standard exposure image signal photographed at an exposure time shorter than the standard are provided for the same scene. In a video signal processing device having a video signal synthesizing unit for synthesizing a video signal whose dynamic range is expanded by using these, the standard exposure video signal and the non-standard exposure video signal according to the video signal level A noise removal unit for removing a noise component according to the ratio of the standard exposure video signal and the non-standard exposure video signal included in the composite video signal and the signal level of the composite video signal to the composite video signal synthesized by A video signal processing device characterized by the above, and has an effect of removing a noise component of a composite video signal and improving S / N.

According to a seventh aspect of the present invention, the noise removing means includes a digital filter for passing the composite video signal, a weighting means, and a video signal level detecting means, and the non-standard exposure video of the composite video signal. The video signal from the video signal synthesizing means is designed so that the digital filter is passed according to the ratio in a portion where the signal ratio is large, and the digital filter is not passed according to the ratio in the portion where the standard exposure video signal is large. 7. The video signal processing device according to claim 6 , wherein the weighting means is controlled by a control signal generated by the video signal level detecting means based on a composite control signal, wherein a noise component of the composite video signal is removed. , S / N are improved.

According to an eighth aspect of the present invention, a standard exposure video signal photographed with a standard exposure time and a non-standard exposure video signal photographed with an exposure time shorter than the standard are taken for the same scene. And a video signal processing method for synthesizing a video signal whose dynamic range has been expanded by using the above, in the video signal processing method, the standard exposure video signal and the non-standard exposure video signal are synthesized in accordance with the video signal level. On the other hand, a noise component is removed for each different exposure amount according to the ratio of the standard exposure video signal and the non-standard exposure video signal included in the composite video signal and the signal level of the composite video signal. This is a video signal processing method, and has an effect of removing noise components of a composite video signal and improving S / N.

According to a ninth aspect of the present invention, in the same scene, a standard exposure video signal photographed with a standard exposure time and a non-standard exposure video signal photographed with an exposure time shorter than the standard exposure time are used. In a video signal processing device having a video signal synthesizing means for synthesizing a video signal whose dynamic range is expanded by using these, the standard exposure video signal and the non-standard exposure video signal are set to a video signal level. According to the ratio of the standard exposure video signal and the non-standard exposure video signal included in the composite video signal and the signal level of the composite video signal included in the composite video signal, a noise component is generated for each different exposure amount. A video signal processing device characterized by comprising a plurality of noise removing means having different characteristics to be removed, wherein the noise component of a composite video signal is removed to improve S / N. Having.

According to a tenth aspect of the present invention, the noise removing means has a plurality of narrow band and wide band digital filters for passing the composite video signal, and a plurality of weighting means for weighting the plurality of digital filters. And an N-stage video signal level detecting means for detecting the signal level of the composite video signal and a selector means for selecting the output of the plurality of weighting means, and a portion of the composite video signal having a large proportion of non-standard exposure video signals. Then, output the video signal that has passed through the wideband digital filter according to the ratio,
In the portion where the standard exposure video signal is large, the N-stage video signal level is output based on the video signal synthesizing control signal from the video signal synthesizing unit so as to output the video signal that has passed through the narrow band digital filter according to the ratio. 10. The video signal processing device according to claim 9 , wherein the weighting means and the selector means are controlled by the control signal generated by the detecting means, wherein the noise component of the composite video signal is removed and the S / N is improved. Has the effect of

According to an eleventh aspect of the present invention, a standard exposure video signal photographed with a standard exposure time and a non-standard exposure video signal photographed with an exposure time shorter than the standard are taken for the same scene. And a video signal processing method for synthesizing a video signal whose dynamic range has been expanded by using the above, in the video signal processing method, the standard exposure video signal and the non-standard exposure video signal are synthesized in accordance with the video signal level. In contrast, the ratio of the standard exposure video signal and the non-standard exposure video signal included in the composite video signal, the signal level of the composite video signal, the exposure time of the standard exposure video signal and the previous non-standard exposure video signal A video signal processing method is characterized in that a noise component is removed for each different exposure amount according to the ratio.
Has the effect of improving.

According to a twelfth aspect of the present invention, a standard exposure video signal photographed with a standard exposure time and a non-standard exposure video signal photographed with an exposure time shorter than the standard are taken for the same scene. In a video signal processing device having a video signal synthesizing means for synthesizing a video signal whose dynamic range is expanded by using these, the standard exposure video signal and the non-standard exposure video signal are set to a video signal level. The ratio of the standard exposure video signal and the non-standard exposure video signal included in the composite video signal, the signal level of the composite video signal, the standard exposure video signal and the non-standard with respect to the composite video signal synthesized according to A video signal processing device comprising a plurality of noise removing means having different characteristics for removing a noise component for each different exposure amount according to the ratio of the exposure time of the exposure video signal. There, removes a noise component of the composite video signal has the effect of improving the S / N.

According to a thirteenth aspect of the present invention, the noise removing means comprises a set of a plurality of narrow band and wide band digital filters for passing the composite video signal, a set of a plurality of weighting means, and a combination. An N-stage video signal level detecting means for detecting the signal level of the video signal, a set consisting of a plurality of selector means for selecting the output of each weighting means, a selector for selecting the output of each selector means, and a standard An exposure ratio calculating means for generating a control signal according to the ratio of the exposure time of the exposure video signal and the exposure time of the non-standard exposure video signal is provided. According to the ratio, the video signal that has passed through the wideband digital filter is output, and in the portion where the standard exposure video signal is large, the signal is passed through the narrowband digital filter according to the ratio. The weighting means and the selector means of each set are controlled by the control signal generated by the N-stage video signal level detecting means based on the video signal synthesizing control signal from the video signal synthesizing means so as to output the video signal. The final selector is controlled by a control signal from the exposure ratio calculation means.
12 is a video signal processing device, which has an effect of removing a noise component of a composite video signal and improving S / N.

According to a fourteenth aspect of the present invention, the image pickup device is provided as a photographing means, and the image signal photographed by the photographing means is processed, and the invention according to any one of the first to thirteenth aspects. An image pickup apparatus having a video signal processing method or apparatus, and having an effect of removing a noise component of a composite video signal and obtaining a good video signal having a high dynamic range and good S / N.

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a block diagram showing a signal processing apparatus according to a first embodiment of the present invention, which is different from the conventional signal processing apparatus shown in FIG.
The digital filter A1100 is further provided in the subsequent stage, and the other constituent elements having the same names and the same numbers have the same functions as those of the conventional example of FIG.
Further, here, the dynamic range expansion processing in units of frames will be described.

In FIG. 1, reference numeral 1010 denotes an image pickup device, which alternately outputs two kinds of image signals of exposure time of standard exposure and non-standard exposure. Reference numeral 1020 denotes an image pickup device driving means, which drives the image pickup device 1010 and
As in (A), the exposure time identification signal 1021 indicating the exposure time of the image sensor is output. Reference numeral 1030 denotes a pre-processing means, which is a CDS circuit for removing the noise component of the analog signal of the image pickup device by correlated double sampling, and an amplitude adjustment so that the analog video signal from which the noise component is removed maintains a constant signal level. And an AGC circuit for performing A.C., and a clamp circuit for clamping the A / D converted analog video signal for A / D conversion.

Reference numeral 1040 is an A / D converter for converting the output of the preprocessing means 1030 into a digital signal, and 1050
Is a means of synchronization. As shown in FIG. 12, the synchronization means 1050 is composed of a memory means 10511 for delaying a video signal for one frame, a selector means 10513 and a selector means 10514. Therefore, in FIG.
As shown in FIG. 3 (A), A / D converter outputs 1041 with different exposure times alternately output for each frame are given to the memory means 10511, the selector means 10513, and the selector means 10514, and the memory means 10511 After delaying the video signal by one frame as shown in FIG. 13B, the memory means output 10512 is set to the selector means 1
0513 and the selector means 10514, and further the selector means 10513 and the selector means 10514 are shown in FIG.
Switching is performed by the exposure time identification signal 1021 shown in FIG. 13C, and as shown in FIGS. 13D and 13E, the output of the selector means 10514 is always the non-standard exposure video signal 1070 (S).
HORT) and selector means 10513
The output is divided into two systems so that the standard exposure video signal 1060 (LONG) is always output, and output at the same timing. Reference numeral 1100 denotes a digital filter A for removing a noise component of the non-standard exposure video signal 1070, and 1080 denotes a standard exposure video signal 1060 and a non-standard exposure video signal 107.
Video signal synthesizing means for synthesizing 0 according to the signal level, 1
Reference numeral 090 denotes a camera process that performs gamma correction, contour correction, and the like on the composite video signal 1081.

The operation of the signal processing apparatus according to the first embodiment of the present invention configured as above will be described. The image sensor 1010 is an image sensor driving unit 102.
Driven by 0, it converts the amount of light into an electrical signal. The image sensor driving means 1020 drives the image sensor 1010 and also generates an exposure time identification signal 1021 indicating the exposure time of the image sensor 1010 as shown in FIG.

The pre-processing means 1030 includes CDS, AGC,
The noise component of the analog signal output from the image sensor 1010, which is configured by a clamp circuit, is removed by correlated double sampling by the CDS circuit, and the analog video signal from which the noise component is removed is held at a constant signal level by the AGC circuit. Amplitude is adjusted to, and clamped by a clamp circuit to perform A / D conversion on the amplitude-adjusted analog video signal,
The A / D converter 1040 converts the clamped analog video signal into a digital video signal.

Next, the operation of the synchronization means 1050 will be described. The synchronization means 1050 is a memory means 10511 for delaying a video signal for one frame as shown in FIG.
And the selector means 10513 and the selector means 10514, and the A / D converter output 1041 is stored in the memory means 1
0511, selector means 10513, and selector means 10
A video signal having a different exposure time, which is given to 514 and then alternately output for each frame as shown in FIG. 13A, is delayed by one frame in the memory means 10511 as shown in FIG. Means 10512 for selector means 10
513 and selector means 10514.

Further, in the synchronizing means 1050, the selector means 10513 and the selector means 10514 are shown in FIG.
It is switched by the exposure time identification signal 1021 of (C). For example, in the selector means 10513 of FIG. 12, when the exposure time identification signal 1021 is 64, the A / D converter output 1021 is output, when the exposure time identification signal 1021 is 2, the memory output 10512 is output, and the selector The means 10514 outputs the memory output 10512 when the exposure time identification signal 1021 is 64 and outputs the A / D converter output 1041 when the exposure time identification signal 1021 is 2. At this time, the exposure time identification signal 1021
13 is weighted according to the exposure time so that the standard exposure video signal is 64 and the non-standard exposure video signal is 2 with respect to the A / D converter output 1041 shown in FIG.
3 (D) and (E), selector means 1051
3 outputs are always the standard exposure video signal 1060 (LONG), and the selector means 10514 is always the non-standard exposure video signal 1070 (SHORT) so that they can be output at the same timing. Become. In this way, the synchronization means 1050 synchronizes the standard exposure and non-standard exposure image signals.

Next, the standard exposure video signal 1060 and the non-standard exposure video signal 1070 will be described. FIG. 14A shows the characteristics of the standard exposure video signal 1060, and FIG.
Shows the characteristics of the non-standard exposure video signal. FIG. 14 (A),
As can be seen from (B), the non-standard exposure video signal 1070
And the standard exposure video signal have different characteristics of the image sensor output with respect to the incident light amount, and the standard exposure video signal 1060 is saturated when the incident light amount exceeds the saturation level of the image sensor, but the S / N is good as a whole. is there. On the other hand, the non-standard exposure video signal 1070 has a characteristic that the output is not saturated even if the incident light amount is large, but the S / N is deteriorated in the region where the incident light amount is small. Therefore, as shown in FIG. 15F, the standard exposure video signal 1060 and the non-standard exposure video signal 1
070 is a video signal synthesizing means 1080 according to the signal level.
In the area where the composite video signal 1081 changes from the vicinity of the MIX area to the SHORT area, the non-standard exposure video signal 1070 having a relatively small incident light amount is used as the composite video signal 1081, and thus the S / N is deteriorated. It becomes a video signal.

Therefore, in order to improve the S / N, noise is to be removed by a digital filter in the process inside the camera process 1090, and the standard exposure video signal 1060 shown in FIG. Since the digital filter processing is performed even on the video signal in the LONG area generated by, the resolution will be deteriorated. Therefore, in the first embodiment, the composite video signal 10
In order to improve the S / N of 81, a digital filter A1100 is provided as shown in FIG. 1, and only the non-standard exposure video signal 1070 is passed through the digital filter A1100 to remove noise components. The standard exposure video signal 1 according to the signal level in the synthesizing means 1080
By synthesizing 060 and the non-standard exposure video signal 1070, a good high dynamic range video signal with improved S / N can be obtained as the composite video signal. Therefore, even if various signal processes are performed by the camera process 1090 in the subsequent stage, it is possible to obtain a good video signal with few noise components.

(Embodiment 2) FIG. 2 is a block diagram showing a configuration of a signal processing apparatus according to a second embodiment of the present invention, which is different from the conventional signal processing apparatus shown in FIG.
A digital filter A1100 and a weighting means 1110 are further provided after the video signal synthesizing means 1080,
Furthermore, the composite video signal 10 from the video signal composition means 1080
The K (video signal synthesis control signal) 1082 indicating the ratio of the standard exposure video image signal 1060 to the non-standard exposure video signal 1070 with respect to 81 is output to the weighting means 1110. The constituent elements having the same numbers have the same functions as those in FIG.

In the second embodiment, in order to remove the noise component of the composite video signal 1081 and improve the S / N, the video signal synthesizing means 1080 generates it.
The output of the digital filter A1100 is controlled by using K (video signal synthesis control signal) 1082 shown in (E). Since K (video signal composition control signal) 1082 indicates the ratio of the standard exposure video signal 1060 and the non-standard exposure video signal 1070 to the composite video signal 1081, the ratio of the non-standard exposure video signal 1070 is used by using this. In many parts, the composite video signal 1081 is output to the digital filter A.
The video signal from which the noise component is removed through 1100 is used as the output of the weighting means 1110, and the standard exposure video signal 1060 is output.
Of the digital filter A1100
The video signal that does not pass is controlled to be output as the weighting means 1110.

For example, the output of the weighting means 1110 is OU
When T and K (video signal synthesis control signal) 1082 are K, the digital filter A1100 output is AOUT, and the synthesized video signal 1082 is MOUT, OUT = K × (AOUT) + (1-K) × MOUT The weighting means 1100 is controlled by K (video signal synthesis control signal) 1082. This makes K
It becomes possible to control the output of the digital filter A1100 in the output of the weighting means 1110 while following the change of (video signal synthesis control signal) 1082.

As described above, according to the second embodiment,
The input video signal of the camera process 1090 follows the ratio of the standard exposure video signal 1060 and the non-standard exposure video signal 1070 included in the composite video signal 1082, and the noise can be removed by the digital filter A1100, so that resolution deterioration is suppressed. , S / N is improved and a good high dynamic range video signal is obtained. Therefore, even if various signal processing is performed by the camera process 1090 in the subsequent stage,
A good video signal with less noise components can be obtained.

(Embodiment 3) FIG. 3 is a block diagram showing the configuration of signal processing in the third embodiment of the present invention, which is different from the signal processing apparatus in the second embodiment in FIG. Further, a video signal level detecting means 1120 is provided. Other constituent elements having the same configuration and the same name and the same number have the same functions as those in FIG.

The weighting means 1110 is equivalent to the weighting means 1110 described in the second embodiment, but here, α (digital filter control signal) is used.
Controlled by 1121. In this case, the video signal synthesizing unit 1080 outputs the K (video signal synthesizing control signal) 1082 shown in FIG.
And outputs the composite video signal 1081 to the video signal level detecting means 1120, the digital filter A 1100 and the weighting means 1110.

The video signal level detecting means 1120 is used for the non-standard exposure video signal 107 included in the composite video signal 1081.
In order to control the output of the digital filter A1100 according to the ratio of 0 and the signal level of the composite video signal 1081, α (digital filter control signal) 1121 as shown in FIG. 4 is generated. By controlling the weighting means 1110 using this α (digital filter control signal) 1121, the noise component is removed.

In the non-standard exposure video signal 1070, the noise component tends to stand out more and the S / N becomes worse as the amount of incident light is smaller.
When combined according to the signal level as in the conventional case shown in (F), the SHORT area of the combined video signal 1081 is mainly composed of the non-standard exposure video signal 1070, and the LON
Since the G area is mainly composed of the standard exposure video signal 1060, the composite video signal 1081 of the SHORT area is generated.
Is a video signal with more noise components than the LONG region and degraded S / N.

In the composite video signal 1081, the area where the noise component is most conspicuous is SH, as shown in FIG.
An area in which the signal level is Yth1 or less in the ORT area and a noise component is inconspicuous because it is bright overall is set in the SHORT area and the signal level is Yth2 or more, and the signal level of the composite video signal 1081 is Y. , Below, α (digital filter control signal)
The control of the weighting means 1110 by the weight of 1121 will be described.

In the composite video signal 1081, since the ratio of the non-standard exposure video signal 1070 becomes large and the noise component becomes conspicuous, the composite video signal 1081 becomes SHO.
In the RT region and the signal level up to Yth1, the video signal is linked with K (video signal combination control signal) 1082 indicating the ratio of the standard exposure video signal 1060 and the non-standard exposure video signal 1070 included in the composite video signal 1081. The output α (digital filter control signal) 1121 of the level detection means 1120 is controlled so that the composite video signal 1081 is gradually passed through the digital filter A1100 to increase the ratio of the digital video signal from which the noise component is removed. For the combined video signal 1081 in the SHORT area where the noise component is most conspicuous and in the area of Yth1 or less, α = 1 is set so that the combined video signal 1081 has all the noise components removed through the digital filter A1100. The weighting means output 1110 Control.

Then, the signal level Y of the composite video signal 1081 becomes high, and when the signal level is Yth2 or higher, the noise component becomes inconspicuous as a whole, and accordingly, the output of the weighting means 1110 is the composite video signal 10.
In order that 82 may not pass through the digital filter A1100 gradually, α (digital filter control signal) 1121 output from the video signal level detecting means 1120 is controlled to be gradually decreased.

The output of the weighting means 1110 is controlled by the α (digital filter control signal) 1121. As the α (digital filter control signal) 1121 becomes smaller, the ratio of passing the composite video signal 1081 through the digital filter A1100 is reduced to reduce the resolution. Control to suppress. This α (digital filter control signal) 1121 is generated as shown in FIG. 4 and is expressed by the following equation. 0 ≦ Y ≦ th1 α = K (video signal synthesis control signal) 1082 SHORT region and th1 ≦ Y ≦ th2 region α = (th2-Y) / (th2-th1) SHORT region and Y ≧ th2 region region α = 0

In this way, the weighting means 1110 uses α
As the (digital filter control signal) 1121 increases, the digital filter A1100 increases the ratio of the digital video signal from which the noise component is removed. As the α (digital filter control signal) 1121 decreases, the digital filter A1100 is not passed. The output is controlled to increase the ratio of the video signal.

For example, the output of the weighting means 1110 is OU
T, α (digital filter control signal) 1121 is α,
When the output of the digital filter A1100 is AOUT and the composite video signal 1082 is MOUT, it is expressed by the following equation. OUT = α × (AOUT) + (1−α) × MOUT

As a result, in the MIX region and the region up to Yth1 shown in FIG. 4 where the noise component of the composite video signal 1081 becomes gradually more noticeable, the digital filter A1
The noise removal effect of 100 is gradually enhanced, and the noise level is the most noticeable in the SHORT region and the signal level th1.
In the region up to, the effect of noise removal by the digital filter A1100 is maximized, and in the region of Yth1 ≦ Y ≦ Yth2 where the noise component is conspicuous, the effect by the digital filter A1100 can be gradually weakened. Therefore, for the other parts, the digital filter A
Since 1100 is not passed, deterioration of resolution is suppressed.

As described above, according to the third embodiment,
Even if various signal processes are performed by the camera process 1090 in the subsequent stage, it is possible to obtain a good high dynamic range video signal with less noise components and less resolution degradation.

(Embodiment 4) FIG. 5 is a block diagram showing a configuration of signal processing according to a fourth embodiment of the present invention, which is different from the signal processing apparatus according to the embodiment shown in FIG.
Instead of the weighting means 1110, the weighting means A11
11, a weighting means B1112, a selector means 1150, a digital filter B1101, and
An N-stage video signal level detecting means 1130 is provided. The other constituent elements having the same configuration and the same name and the same number have the same functions as those in FIG. In addition,
The weighting means A1111 and the weighting means B1112 are
It is similar to the weighting means 1110 described in the second embodiment, but here, it is controlled by αn (digital filter control signal) 1131 and βn (digital filter control signal) 1132.

In addition, the digital filter A1 is previously set.
The characteristics of 100 and the digital filter B1101 are made different. For example, the characteristic of the digital filter A1100 as shown in FIG. 6A is provided as a narrow band steep characteristic with respect to the characteristic of the digital filter B1101 shown in FIG. 6B. A filter having a sharp characteristic in a narrow band as shown in FIG. 6A has a characteristic of having a high S / N improvement capability although the deterioration of resolution is large, and a filter having a wide band as shown in FIG. 6B is gentle. The characteristic filter has a characteristic that the deterioration of resolution is small but the S / N improving ability is low. Therefore, by utilizing this, the weighting means A1111 and the weighting means B1112 are controlled to be included in the composite video signal 1081. Noise removal is performed by the digital filter A1100 and the digital filter B1101 according to the noise component to be generated.

Video signal synthesizing means 108 shown in FIG. 7 (A).
1 is K (video signal synthesis control signal) 1 shown in FIG.
082 is output to the N-stage video signal level number detecting means 1130, and the composite video signal 1081 is output to the digital filter A11.
00, digital filter B1101, weighting means A1111, and N-stage video signal level number detection means 1130.

In the N-stage video signal level detecting means 1130, K indicating the ratio of the standard exposure video signal 1060 and the non-standard exposure video signal 1070 contained in the composite video signal 1081.
(Video signal composition control signal) 1082 and composite video signal 1
Depending on the signal level with 081, the composite video signal 1081
It generates a n (digital filter control signal) 1131, βn (digital filter control signal) 1132, and S (selector control signal) 1133 that control weighting of the digital filter A 1100 and the digital filter B 1101.

For example, the non-standard exposure video signal 1070 is
The smaller the amount of incident light, the more noticeable the noise component is. S / N
As shown in FIG. 7 (A),
The signal level of the composite video signal 1081 is Y, and in the composite video signal 1081, the region where the noise component gradually stands out is the MIX region and up to Yth1, and the region where the noise component is most noticeable is the SHORT region and Yth1, and further next. SHO the area where the noise component is easily noticeable
Since the RT region and Yth1 to Yth2 and the signal level Yth2 and above are bright, the noise component is not so noticeable, and the composite video signal 1081 is divided into the following regions to control the output of the selector means 1150 by αn ( Digital filter control signal) 1131,
βn (digital filter control signal) 1132 and S
(Selector control signal) 1133 is generated.

LONG area → composite video signal 1081
Which does not pass through the digital filter A1100. MIX area → A composite image signal 1081 is weighted and combined into a signal which is passed through the digital filter A1100 and a signal which is not passed through the digital filter A1100. SHORT area and Y ≦ th1 area → The composite video signal 1081 is passed through the digital filter A1100. SYORT region and th1 ≤ Y ≤ th2 region → The composite video signal 1081 is passed through the digital filter B1100 and the composite video signal 1081 is passed through the digital filter B1101 and weighted and combined. A SHORT area and an area of th2 ≦ Y → A composite video signal 1081 passed through a digital filter B1101.

Further, αn (digital filter control signal) 1131 and βn (digital filter control signal) 1132 and S (selector control signal) generated by this control.
1133 is shown in the following formulas. 0 ≦ Y ≦ th1 αn = K (video signal synthesis control signal) 1082, βn =
0, S = 0 SHORT region and th1 ≦ Y ≦ th2 region αn = 1 βn = (Y-th1) / (th2-th1) S = 1 SHORT region and th2 ≦ Y region αn = 0, βn = 1, S = 1

FIG. 7 (C) shows αn (digital filter control signal) 1131, FIG. 7 (D) shows βn (digital filter control signal) 1132, and FIG. 7 (E) shows S.
(Selector control signal) 1133 is shown. The αn (digital filter control signal) 1131 and βn (digital filter control signal) 1132 are used for weighting means A11.
11 and the weighting means B 1112 are controlled, and the selector means 1150 is controlled by S (selector control signal) 1133.

For example, the output of the weighting means A1111 is A
OUT, αn (digital filter control signal) 1131
Is αn and the digital filter A1100 output is AFOU
T, the composite video signal 1082 is assigned to MOUT weighting means B1.
112 output is BOUT, βn (digital filter control signal) 1131 is βn, digital filter B1101
When the output is BFOUT, the weighting means A1111 output and the weighting means B1112 output are expressed by the following equations (10) and (11).
Indicated by. (10) AOUT = αn × (AFOUT) + (1-αn)
× MOUT (11) BOUT = βn × (BFOUT) + (1-βn)
× MOUT The selector means 11 outputs the weighting means A1111 output (AOUT) and the weighting means B1112 output (BOUT).
50, and the signal level Yt of the composite video signal 1081
S (selector control signal) shown in formulas based on h1
1133 controls the output of the selector means 1150.

As a result, the video signal in the LONG area which originally has a good S / N ratio of the composite video signal 1081 does not pass through the digital filter A1100 and the digital filter B1101, and the MIX area is weighted by αn (digital filter control signal) 1131. Since the means A1111 can control, it is possible to remove noise by weighting the digital filter A1100, and αn (digital filter control signal) 1131 for the region where the noise component is most noticeable (SHORT region and Y ≦ th1 region).
Since the weighting means A1111 can be controlled by the above, it is possible to remove noise making the most of the effect of the narrow band digital filter A1100. Next, a region where noise components are easily noticeable (SHORT region and th1 ≦ Y ≦ th2 region)
For αn (digital filter control signal) 11
31 and βn (digital filter control signal) 1132, weighting means A 1111 and weighting means B 1112
Can control the narrow band digital filter A11.
00 and a wide band digital filter B1101 can be weighted for noise removal. In addition, it is a bright area where noise components are not so noticeable (SHORT area and th
In the range of 2 ≦ Y), it becomes possible to remove noise with less resolution deterioration by the wide band digital filter B1101. Therefore, noise components are removed from the composite video signal 1081 while suppressing deterioration of resolution, and S / N is eliminated.
Can be improved.

As described above, according to the fourth embodiment,
Even if various signal processes are performed by the camera process 1090 in the subsequent stage, it is possible to obtain a good video signal with less noise components and less deterioration in resolution.

In this example, only two digital filters are used, but by using more digital filters having different characteristics, it is possible to perform noise removal suitable for the characteristics of the output of the image pickup device 1010.

(Fifth Embodiment) FIG. 8 is a block diagram showing a configuration of a signal processing apparatus according to a fifth embodiment of the present invention, in which an exposure ratio is calculated in comparison with the fourth embodiment of FIG. Means 1210, digital filter C1102, digital filter D1103, and weighting means C1113
, Weighting means D1114, and selector means 1151
And selector means 1152. Other constituent elements having the same structure and the same name and the same number have the same functions as those in FIG.

The weighting means C1113 and the weighting means D1114 are the same as the weighting means 1110 described in the second embodiment, but here, αn (digital filter control signal) 1131 and βn, respectively.
It is controlled by (digital filter control signal) 1132. In this case, two sets of digital filters having different characteristics are prepared in advance. Here, one set is a digital filter A1100 and a digital filter B110.
1 and the other set is a digital filter C1102 and a digital filter D1103.

For example, as shown in FIGS. 9A to 9D, as the band of each digital filter, digital filter A1100 <digital filter C1102 <digital filter B1101 <digital filter D1
It is provided to be 103. A narrow-band steep characteristic filter has a large deterioration of resolution, but has a characteristic of high S / N improvement capability. A wide-band gradual characteristic filter has a small deterioration of resolution, but has a low S / N ratio. Since the improvement ability is low, the weighting means A1111, the weighting means B1112, the weighting means C1113, and the weighting means D1114 are used to control the digital signal according to the noise component included in the composite video signal 1081. Noise removal can be performed using the filter A1100 and the digital filter 1101.

First, in the exposure ratio calculation means 1210 of FIG. 8, the standard exposure video signal 1060 and the non-standard exposure video signal 1070 are based on the exposure time identification signal 1021 shown in FIG. The exposure ratio signal 1211 shown in FIG. 11B is generated in accordance with the ratio of the exposure times.

Next, the N-stage video signal level detecting means 11
In 90, as in the fourth embodiment, the composite video signal 1
No. 081 includes a K (composite video signal control signal) 1082 indicating the ratio of the non-standard exposure video signal 1070, and αn (digital filter control signal) 1131 and βn (digital filter) depending on the signal level of the composite video signal 1081. Control signal) 1132 and S (selector control signal) 1
133, and controls the weighting means A1111, the weighting means B1112, the weighting means C1113, and the weighting means D1114.

The outputs of the weighting means A1111 and the weighting means B1112 are respectively the selector means 1
150, and outputs the weighting means C1113 output and the weighting means D1114 output to the selector means 115, respectively.
Enter 1. As a result, one set of digital filter A1100 and digital filter B1101
A pair of digital filter C1102 and digital filter D1103 are configured, and selector means 1150,
The output of the selector means 1151 is further added to the selector means 115.
2 and controls the selector 1152 by the exposure ratio signal 1141 indicating the ratio of the exposure time of the standard exposure video signal 1060 and the non-standard exposure video signal 1070.

The exposure ratio signal 1141 is converted into the standard exposure video signal 1060 and the non-standard exposure video signal 10 as shown in FIG.
When the ratio of 70 is 32 times or more, it is weighted as 1 and when it is less than 0, it is weighted as 0. When the exposure ratio signal 1141 is 0, the digital filter A1100 and the digital filter B1101 remove noise components from the composite video signal 1081. When the exposure ratio signal 1141 is 1, the composite video signal 1081 is generated so that noise components can be removed by the digital filter C1102 and the digital filter D1103, and the selector means 1152 is controlled by this exposure ratio signal 1141. To do.

Here, when the ratio of the exposure time is large, the non-standard exposure video signal 1 is compared with the standard exposure video signal 1060.
It is considered that the exposure time of 070 is short. In such a case, in the non-standard exposure video signal 1070, the S / N is deteriorated as the exposure time is shorter, and the noise component tends to be noticeable. Therefore, the digital filter A1100 and the digital filter B1101 having a relatively narrow band are selected. Then, the video signal from which the noise component is removed is selected by the selector means 11
52 output, and conversely, when the ratio of the exposure time is small, it is considered that the exposure time of the non-standard exposure video signal 1070 is longer than that of the standard exposure video signal 1060. Non-standard exposure video signal 10
Since the noise component of 70 is relatively inconspicuous and the S / N is not deteriorated so much, the digital signal C1102 and the digital filter D1103 having a relatively wide band are selected and the video signal from which the noise component is removed is selected by the selector means 11.
52 outputs. As a result, the noise component included in the composite video signal 1081 is the standard exposure video signal 1060 and the non-standard exposure video signal 10 included in the composite video signal 1081.
It will be removed depending on the ratio of 70, the signal level, and the exposure time.

As described above, according to the fifth embodiment,
By preparing four digital filters having different characteristics, the noise component is made to follow the ratio of the standard exposure video signal 1060 and the non-standard exposure video signal 1070 included in the composite video signal 1081, the signal level and the exposure time ratio. An optimum digital filter can be selected to remove the noise, and more effective noise removal can be performed while suppressing resolution deterioration. Therefore, even if various signal processes are performed by the camera process 1090 in the subsequent stage, it is possible to obtain a good video signal with a good S / N and little deterioration in resolution.

Although only four digital filters are used in this example, by using more digital filters having different characteristics, it is possible to perform appropriate noise removal suitable for the characteristics of the output of the image sensor 1010. .

[0078]

[0079]

As described above, according to the present invention, the standard exposure image included in the composite image signal is compared with the composite image signal obtained by combining the standard exposure image signal and the non-standard exposure image signal according to the signal level. Depending on the ratio of the signal to the non-standard exposure video signal, the noise component is removed to reduce the resolution.
While suppressing, it is possible to obtain a composite video signal having a high S / N and a high dynamic range with an improved noise component.

By removing the noise component from the composite video signal according to the signal level of the composite video signal, the ratio of the non-standard exposure video signal included in the composite video signal, and the signal level of the composite video signal. It is possible to obtain a composite video signal with a high S / N and a high dynamic range while suppressing resolution deterioration.

Further, a plurality of noise removing means having different characteristics for removing noise from the combined video signal are provided.
Depending on the signal level of the composite video signal and the ratio of the non-standard exposure video signal and the standard exposure video signal included in the composite video signal,
By selectively using a plurality of noise removing means having different characteristics, it is possible to perform more effective noise removal while suppressing resolution degradation.

With respect to the composite video signal, the ratio of the exposure time of the standard exposure video signal to the non-standard exposure video signal of the composite video signal, the signal level of the composite video signal, and the non-standard exposure included in the composite video signal. By selectively using a plurality of noise removing means having different characteristics according to the ratio of the image signal and the standard exposure image signal, it is possible to suppress the deterioration of resolution and perform more effective and appropriate noise removal.

Further, the image pickup apparatus of the present invention using the above noise removing means can overcome the shortcomings of the solid-state image pickup element and pick up a good image having a high dynamic range with few noise components.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a signal processing device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a signal processing device according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a signal processing device according to a third embodiment of the present invention.

FIG. 4 is a characteristic diagram showing characteristics of α (digital filter control signal) in the video signal level detecting means.

FIG. 5 is a block diagram showing a configuration of a signal processing device according to a fourth embodiment of the present invention.

FIG. 6 is a characteristic diagram showing characteristics of a digital filter A and a digital filter B according to a fourth embodiment of the present invention.

FIG. 7A is a characteristic diagram of a composite video signal input to an N-stage video signal level detecting means, FIG. 7B is a characteristic diagram of K (video signal synthesis control signal), and is a characteristic diagram of αn (digital filter control signal). D) βn (digital filter control signal) characteristic diagram (E) S (selector control signal) characteristic diagram

FIG. 8 is a block diagram showing a configuration of a signal processing device according to a fifth embodiment of the present invention.

FIG. 9 is a digital filter A, a digital filter B, and a digital filter C according to the fifth embodiment of the present invention.
And characteristic diagram showing the characteristics of the digital filter D

FIG. 10 is a block diagram showing a configuration of a conventional signal processing device.

FIG. 11A is a characteristic diagram showing characteristics of an exposure time identification signal. (B) Characteristic diagram showing the characteristics of the exposure ratio signal

FIG. 12 is a block diagram showing the configuration of the synchronization means.

FIG. 13 is a characteristic diagram showing (A) A / D converter output. (B) Characteristic diagram showing memory means output (C) Characteristic diagram showing an exposure time identification signal (D) Characteristic diagram showing non-standard exposure video signal (E) Characteristic diagram showing standard exposure video signal

14A is a characteristic diagram showing the characteristics of a standard exposure video signal: LONG, and FIG. 14B is a characteristic diagram showing the characteristics of a non-standard exposure video signal: SHORT, and FIG. 14C is an offset (OFSET) to the nonstandard exposure video signal.
Characteristic diagram showing the characteristics when 1) is added

FIG. 15 (D) is a characteristic diagram showing the combination of the standard exposure video signal (LONG) and the non-standard exposure video signal (SHORT). (E) is a characteristic diagram showing the characteristics of K (video signal combination control signal). Characteristic diagram showing characteristics of video signal

[Explanation of symbols]

1010 image sensor 1020 Image sensor driving means 1021 exposure time identification signal 1030 pretreatment means 1040 A / D converter 1041 A / D converter output 1050 synchronization means 10511 memory means 10512 Memory means output 10513 selector means 10514 Selector means 1060 standard exposure signal 1070 Non-standard exposure signal 1080 video signal synthesis control means 1081 Composite video signal 1082 K (video signal synthesis control signal) 1090 camera process 1100 Digital filter A 1101 Digital filter B 1102 Digital filter C 1103 Digital filter D 1110 Weighting means 1111 Weighting means A 1112 Weighting means B 1113 Weighting means C 1114 Weighting means D 1120 Video signal level detection means 1121 α (digital filter control signal) 1130 N-stage video signal level detection means 1131 αn (digital filter control signal) 1132 βn (digital filter control signal) 1140 Exposure ratio calculation means 1141 Exposure ratio signal 1150 selector means 1151 selector means 1152 selector means

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Claims (14)

(57) [Claims] 1. A standard exposure image signal photographed with a standard exposure time and a non-standard exposure image signal photographed with an exposure time shorter than the standard are generated for the same scene, and a dynamic range is generated using these signals. In a video signal processing method for synthesizing an enlarged video signal, a standard included in the synthetic video signal with respect to a synthetic video signal obtained by synthesizing the standard exposure video signal and the non-standard exposure video signal according to a signal level. A video signal processing method characterized by removing a noise component according to a ratio of an exposure video signal and a non-standard exposure video signal. 2. A noise component is removed according to the ratio in a portion where the ratio of the non-standard exposure video signal is high, and a noise component is removed according to the ratio in a portion where the ratio of the standard exposure video signal is high. The video signal processing method according to claim 1 , wherein the video signal processing method is absent. 3. A standard exposure image signal photographed with a standard exposure time and a non-standard exposure image signal photographed with an exposure time shorter than the standard are generated for the same scene, and a dynamic range is generated using these signals. In a video signal processing device having a video signal synthesizing means for synthesizing an enlarged video signal, the standard exposure video signal and the non-standard exposure video signal are synthesized in accordance with a signal level, A video signal processing device comprising: a noise removing unit for removing a noise component according to a ratio of a standard exposure video signal and a non-standard exposure video signal included in a composite video signal. 4. The noise removing means comprises a digital filter for passing the composite video signal and a weighting means, and in the portion of the composite video signal in which the proportion of the non-standard exposure video signal is large, the digital filter is provided in accordance with the proportion. The weighting means is controlled by the video signal synthesis control signal from the video signal synthesis means so that the digital filter is not passed through in a portion where the standard exposure video signal is large, according to the ratio. Item 3. The video signal processing device according to Item 3 . 5. A standard exposure video signal photographed with a standard exposure time and a non-standard exposure video signal photographed with an exposure time shorter than the standard are generated for the same scene, and a dynamic range is generated using these signals. In a video signal processing method for synthesizing an enlarged video signal, the standard exposure video signal and the non-standard exposure video signal are included in the composite video signal with respect to the composite video signal synthesized in accordance with a video signal level. A video signal processing method, wherein a noise component is removed according to the ratio of the standard exposure video signal to the non-standard exposure video signal and the signal level of the composite video signal. 6. A standard exposure image signal photographed with a standard exposure time and a non-standard exposure image signal photographed with an exposure time shorter than the standard are generated for the same scene, and a dynamic range is generated using these signals. In a video signal processing device provided with a video signal synthesizing means for synthesizing an enlarged video signal, the standard exposure video signal and the non-standard exposure video signal are synthesized in accordance with the video signal level. A video signal processing, characterized in that it comprises a noise removing means for removing a noise component according to a ratio of a standard exposure video signal and a non-standard exposure video signal included in the composite video signal and a signal level of the composite video signal. apparatus. 7. The noise removing means comprises a digital filter for passing the composite video signal, a weighting means, and a video signal level detecting means, and the ratio of the non-standard exposure video signal in the composite video signal is large. The video signal level is detected based on the video signal synthesizing control signal from the video signal synthesizing means so as not to pass the digital filter depending on the ratio in a portion having a large standard exposure video signal. 7. The video signal processing device according to claim 6 , wherein the weighting means is controlled by the control signal generated by the means. 8. A standard exposure image signal photographed with a standard exposure time and a non-standard exposure image signal photographed with an exposure time shorter than the standard are generated for the same scene, and a dynamic range is generated using these signals. In a video signal processing method for synthesizing an enlarged video signal, the standard exposure video signal and the non-standard exposure video signal are included in the composite video signal with respect to the composite video signal synthesized in accordance with a video signal level. A video signal processing method, wherein a noise component is removed for each different exposure amount according to the ratio of the standard exposure video signal to the non-standard exposure video signal and the signal level of the composite video signal. 9. A standard exposure video signal photographed with a standard exposure time and a non-standard exposure video signal photographed with an exposure time shorter than the standard are generated for the same scene, and these are used to generate a dynamic range. In a video signal processing device provided with a video signal synthesizing means for synthesizing an enlarged video signal, the standard exposure video signal and the non-standard exposure video signal are synthesized in accordance with the video signal level. A plurality of noise removing means having different characteristics for removing noise components for different exposure amounts according to the ratio of the standard exposure video signal and the non-standard exposure video signal included in the composite video signal and the signal level of the composite video signal. A video signal processing device comprising: 10. A noise removing means detects a plurality of narrow band and wide band digital filters for passing a composite video signal, a plurality of weighting means for weighting the plurality of digital filters, and a signal level of the composite video signal. The N-stage video signal level detecting means and the selector means for selecting the outputs of the plurality of weighting means are provided, and in the portion where the ratio of the non-standard exposure video signal is large in the composite video signal,
According to the ratio, output the video signal that has passed through the wideband digital filter, and in the portion where the standard exposure video signal is large, output the video signal that has passed through the narrowband digital filter according to the ratio. 10. The video signal processing according to claim 9 , wherein the weighting means and the selector means are controlled by a control signal generated by the N-stage video signal level detecting means based on a video signal synthesizing control signal from the video signal synthesizing means. apparatus. 11. A standard exposure video signal photographed with a standard exposure time and a non-standard exposure video signal photographed with an exposure time shorter than the standard are generated for the same scene, and a dynamic range is generated using these signals. In a video signal processing method for synthesizing an enlarged video signal, the standard exposure video signal and the non-standard exposure video signal are included in the composite video signal with respect to the composite video signal synthesized in accordance with a video signal level. Depending on the ratio of the standard exposure video signal and the non-standard exposure video signal, the signal level of the composite video signal, and the ratio of the exposure time of the standard exposure video signal and the previous non-standard exposure video signal, for each different exposure amount A video signal processing method characterized by removing a noise component. 12. A standard exposure video signal photographed with a standard exposure time and a non-standard exposure video signal photographed with an exposure time shorter than the standard are generated for the same scene, and the dynamic range is generated using these signals. In a video signal processing device provided with a video signal synthesizing means for synthesizing an enlarged video signal, the standard exposure video signal and the non-standard exposure video signal are synthesized in accordance with the video signal level. Depending on the ratio of the standard exposure video signal and the non-standard exposure video signal included in the composite video signal, the signal level of the composite video signal, and the exposure time ratio of the standard exposure video signal and the non-standard exposure video signal. And a plurality of noise removing means having different characteristics for removing noise components for different exposure doses. 13. The noise removing means comprises a set of a plurality of narrow band and wide band digital filters for passing the composite video signal, a set of a plurality of weighting means, and N stages for detecting the signal level of the composite video signal. Video signal level detection means, a set composed of a plurality of selector means for selecting the output of each set of weighting means, a selector for selecting the output of each set of selector means, and a standard exposure video signal and a non-standard exposure video signal An exposure ratio calculating means for generating a control signal according to the ratio of the exposure time, and a portion having a large proportion of the non-standard exposure video signal in the composite video signal is passed through the wide band digital filter according to the proportion. The video signal is output, and in the portion where the standard exposure video signal is large, the video signal is output according to the ratio through the narrow band digital filter. The control signal generated by the N-stage video signal level detecting means based on the video signal synthesizing control signal from the signal synthesizing means controls the weighting means and selector means of each set, and the control signal from the exposure ratio computing means. 13. The video signal processing device according to claim 12 , wherein the final selector is controlled by. 14. an imaging device as an imaging device, further comprising a video signal processing method or apparatus according to any one of claims 1 to 13 for processing the image signal captured by the imaging means An imaging device characterized by.