JP3413776B2 - Imaging device - Google Patents

Description

[0001] The present invention will be described in the following order. Industrial Application Field Means for Solving the Problems to be Solved by the Conventional Technical Invention (FIGS. 1 to 5) Operation (FIGS. 1 to 5) Embodiment (1) Overall Configuration (FIG. 1) (2) ) Digital signal processing circuit (FIG. 2) (3) Peak level detection circuit (FIG. 3) (4) Gate signal generation circuit (FIG. 4) (5) Level detection circuit (FIG. 5) (6) Central processing unit (FIG. 6) (FIG. 8) (6-1) Adjustment of black set (6-2) Setting of white balance (7) Effects of the embodiment (8) Effects of other embodiments of the present invention Relates to an imaging device, for example,
Applicable to television cameras. 2. Description of the Related Art Conventionally, in this type of imaging apparatus,
By adjusting the rack set, the amplification rate of the imaging signal can be increased.
Make sure that the black level does not fluctuate even when
Have been. That is, in this type of imaging apparatus,
Converts the image signal output from the body image sensor to a color signal
Amplify to a predetermined level and turn off the gain when the captured image is dark
This amplification factor can be switched in response to the operation of the switching operator
It has been made like that. At this time, in the image pickup apparatus, a memory
Converts the correction data stored in the circuit to an analog signal and
By adding and subtracting signals, the black level between each color signal
Correct the signal level to make them equal, and then turn off the gain.
This correction data is switched in response to the operation of the switching operator.
To prevent the black level from fluctuating.
I have. [0006] By the way, this kind of imaging
In the device, detect the signal level of each color signal
The gain of the gain amplifier based on this detection result.
Switch to adjust the white balance
It has been done. Further, in an imaging device,
Multiple balance adjustment modes, such as outdoor and indoor
And can adjust the white balance respectively.
When the shooting site is moved from outdoor to indoor,
Switch the white balance adjustment mode to quickly
The balance can be adjusted. However, as described above, white balance adjustment is performed.
When switching between the two, the offset voltage of the gain amplifier
If there is, the black level of the color separation signal also changes,
Lance changes. Compensate for this black balance change
If this is possible, the image quality of the output signal can be improved
You. The present invention has been made in view of the above points.
The black balance associated with switching the white balance adjustment.
We have proposed an imaging device that can compensate for lance changes.
It is to try. Means for Solving the Problems [0009] To solve such problems.
In the present invention, a desired subject is imaged and the color signal S
Imaging means 2 for outputting R, SG, SB, and color signals SR,
SG and SB are amplified and output, and converted to predetermined gain control data.
A signal processing circuit 16 for switching a gain based on the color signal;
The signal levels of SR, SG, and SB are detected, and the signal level is detected.
A signal level detection circuit 90 for outputting the output result;
Output gain control data based on the
How to set white balance for SR, SG, SB
And a predetermined signal level correction data.
Black level of the color signals SR, SG, SB based on the data DP.
A signal level correction circuit 24 for correcting the
A correction data output circuit 10 for outputting the data DP.
The white balance setting circuit 10 includes first and second white balance setting circuits.
It has a light balance setting mode, and
In response, the gain control data is switched and output.
And the gain of the signal processing circuit 16 is adjusted to the first and second white
Set the gain in the balance setting mode, and
The road 10 has the first and second white balance setting modes.
The correction data DP is switched and output in accordance with. According to the present invention, gain control data is generated in response to an operation of a predetermined operation element.
By switching and outputting, the signal processing circuit 16
Set the gain to the value of the first and second white balance setting modes.
And the first and second white baluns
Switching the correction data DP according to the data setting mode and outputting
To adjust the first and second white balance.
Compensates for changes in black balance due to mode switching
can do. An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.
I do. (1) Overall Configuration In FIG. 1, reference numeral 1 denotes an image pickup apparatus as a whole,
Drives the image element (CCD) 2 to image a desired subject
You. That is, the image pickup apparatus 1 includes a timing generator.
TG 4 generates a reference signal, and this reference signal
The solid-state imaging device 2 is driven. The imaging device 1 is a solid-state imaging device.
An aperture 6 and a zoom lens 8 are arranged in front of the
Desirable magnification and brightness on the imaging surface of the solid-state imaging device 2
To form an image of the subject. At this time, the central processing unit (CPU) 10
Detects the magnification of the captured image with the zoom position detection circuit 12.
Then, the control of the aperture 6 is switched based on the detection result,
As a result, even if the magnification changes, the brightness desired by the user is changed.
It is designed to be able to image a subject with a horn. Further, the image pickup apparatus 1 includes a correlated double sampler.
The output signal of the solid-state imaging device 2 is sampled by applying the
Sample and hold in the sample and hold circuit (S / H) 14,
The resulting image signal S1 is transmitted to the AV block circuit 16
Output to The AV block circuit 16 determines whether the image signal S1 is
After each color signal is generated, it is amplified at a predetermined amplification rate.
When correcting the signal level of each color signal,
Coding correction, etc., and further increase the amplification rate.
Switch to adjust white balance and gain up.
Have been made to gain. Analog digital conversion circuit (A / D) 1
8 is a color signal SR output from the AV block circuit 16.
To SB are converted into digital signals and output. The digital signal processing circuit 20 has a predetermined detection function.
The output circuit detects the signal level of each of the color signals SR to SB.
By adjusting the black balance and adjusting the black balance
Adjustment, white balance adjustment, aperture adjustment, flare compensation
Executes the regular data detection process, and if necessary, the detection result
Is output to the central processing unit 10. This allows the imaging device
In the unit 1, the central processing is performed based on the data detection result.
By controlling each signal processing circuit with the logic unit 10,
And adjust the white balance.
You. Further, the digital signal processing circuit 20
The signal level of each color signal based on the data detection results
By correcting flare,
And generates a correction signal SH for correction.
A via a digital / analog conversion circuit (D / A) 22
Output to the V block circuit 16. Thereby, the imaging device 1
In the above, the complement generated by the digital signal processing circuit 20 is used.
Shading correction is performed using the positive signal SH. The video process circuit 24 has a digital signal
Receiving the color signal processed by the signal processing circuit 20,
After processing and knee processing, set the pedestal level. Continued
The encoder circuit 26 converts each color signal into a luminance signal and a color difference.
After being converted into a signal, it is converted into a video signal and output. As a result, in the imaging device 1, the desired
Captures a subject and outputs the video signal SV
Has been made. (2) Digital signal processing circuit As shown in FIG.
The test signal generation circuit 30 generates various test signals TS.
Selectors 32R, 32G, 32B and 34R, 34
G, 34B, and the central processing
This test signal is switched off based on the output signal of the unit 10.
Replace it. Thus, the digital signal processing circuit 20
In the adjustment mode, various test signals T
S can be used to adjust the AV block circuit 16 etc.
Check the overall operation in the self-diagnosis mode
It is made to be able to do. Further, the digital signal processing circuit 20
Clamp level for each color signal SR to SB consisting of digital signals
To the color detection circuit 36, where each color is
The signal levels of the signals SR to SB are detected. More daisy
The total signal processing circuit 20 clears this signal level detection result.
Output to a lamp circuit (not shown), and thereby each color signal
Set the clamp levels of SR to SB. The selectors 32R to 32B operate in a normal operation mode.
Correction by selecting each of the color signals SR to SB
Output to the circuit 38 in the self-diagnosis mode
Switches the contacts at a predetermined timing,
During one horizontal scanning period of the direct blanking period, the color signal SR
And selectively outputs a test signal instead of SB. In contrast
In the adjustment mode, the selectors 32R to 32B
Each adjustment item is controlled by the central processing unit 10.
Switch the contacts at a predetermined timing according to the eyes,
In the image pickup apparatus 1, instead of the color signals SR to SB,
Various test signals are output so that various items can be easily
It is designed to adjust the eyes. The automatic defect detection circuit 40 detects the signal of each color signal.
By continuously monitoring the level, the solid-state image sensor
2 defective pixels are detected, and the positions of the defective pixels are determined by a predetermined method.
Stored in memory circuit. The defect correction circuit 38 uses this memory
According to the contents of the circuit, interpolation calculation processing is performed at the position of the defective pixel.
Execute. As a result, the defect correction circuit 38 detects the defective pixel.
Generates color signals for correction from surrounding pixels, and
The color signal of the defective pixel is replaced with the color signal of the defective pixel. This
The defect correction circuit 38 indicates that a defect has occurred in the solid-state imaging device 2.
Even if the image quality is not significantly degraded
You. The adder circuits 42R-42B perform flare correction
Add flare correction signal output from road 44 to each color signal
Thus, the flare of the captured image is corrected. Note that
The correction circuit 44 applies the calculation result of the central processing unit 10 to the
Generating a flare correction signal based on the
In the imaging device 1, the flare can be performed with a simple adjustment operation.
The correction is made. The selectors 46R-46B are provided with an adder 42
R-42B output signals to the following video processing circuit 24
At this time, the signal level of the selection signal SEL1 is switched off.
When the contact is switched, the output signal
The level falls to the 0 level. Thereby, the imaging device 1
In the adjustment mode, etc.,
The input level of the O-process circuit 24 falls to the 0 level
Circuit block after the video process circuit 24
It can be adjusted to. The low-pass filter circuit (LPF) 48
The color signal output from the defect correction circuit 38
Suppress noise components to eliminate noise components and output
You. The shading correction circuits 50 and 52 have a low-pass
Based on the output signal of the filter circuit 48,
Correction signals SH1 and SH2 are generated, and in the case of this embodiment,
Black with shading correction signals SH1 and SH2 respectively
Correct shading of level and white level. At this time, the shading correction circuit 52
Based on the calculation result D1 of the central processing unit 10, each color
Create correction signal SH2 for shading correction from signal
I do. As a result, the digital signal processing circuit 20
The shading correction signals SH1 and SH2 are AV-blocked.
It returns to the circuit 16 and corrects the shading.
Have been. At this time, the shading correction circuit 50
Outputs correction signal SH1 via selectors 34R-34B
The selectors 34R-34B output the selection signals.
When the signal SEL2 rises, a test is performed instead of the correction signal SH1.
Signal is selectively output. This
In the imaging device 1, if necessary,
Selectively output the positive signal SH1 and the test signal, and
This makes it possible to simplify the work of adjusting the circuit. The data detection circuit 54 is a low-pass filter.
Detects the signal level, etc., of the output signal of the circuit 48
For flare correction and white balance adjustment
Detect data. Of these, data for aperture adjustment
The data detection circuit 54 stores the memo of the defect detection circuit 38.
The data of the detection result is stored in the
Access the contents of the memory circuit from the central processing unit 10.
The aperture can be easily adjusted. (3) Peak level detection circuit As shown in FIG.
In the lance adjustment mode, the peak level detection circuit 5
The peak level is detected in step 6, and the peak level detection result
The white balance adjustment area is set based on. sand
That is, in the peak level detection circuit 56, the arithmetic circuit 58
Is 1/4 by adding the signal levels of the respective color signals SR to SB.
To approximate the color signals SR to SB.
, A luminance signal ADY is generated, and
The luminance signal ADY is output to the tone detection circuit 62. The selector 60 has a predetermined reference signal generation circuit.
With reference to the window signal WHEN generated by
The signal ADY is selectively output, and thereby the periphery of the captured image is
A predetermined effective detection area excluding the side portion (in FIG.
(Corresponding to an area indicated by AR)).
Is output to the peak detection circuit 62. The peak detection circuit 62 outputs the sequentially input brightness.
The peak level is detected from the degree signal ADY, and this detection result
To the latch circuit (L) 66 via the selector 64.
I do. As a result, the peak detection circuit 56
Detects the peak level of the luminance signal within
It is stored in a latch circuit 66. In this embodiment, the peak level detection is performed.
The output circuit 56 controls the peak of the color signal in another adjustment mode.
Level is detected.
0 is used instead of the output signal of the arithmetic circuit 58 if necessary.
Signal NMY (that is, each color signal composed of a digital signal)
The color signal with the highest signal level at each timing
Selected signal).
Have been. In response, the latch circuit 66 selects
The output signal is fed back via the
Switch the selector 64 as necessary to
The updated data can be updated. (4) Gate signal generation circuit The data detection circuit 54 further includes a gate signal generation circuit shown in FIG.
The generation circuit 68 generates a gate signal for data detection. This
As a result, the gate signal generation circuit 68
In the adjustment mode, the signal level of the luminance signal ADY is
By outputting the gate signal GT1 with reference to the reference,
Self-diagnosis while setting the white balance adjustment area
Mode and adjustment mode, the test signal detection
It is designed to be able to set the imming. That is, the gate signal generation circuit 68
A luminance signal ADY is given to the circuits 70 and 72, and
Output comparison result based on PK and LOW
I do. Here, in the comparison reference PK and LOW, the operation is performed.
It can be set by the central processing unit 10 according to the mode.
In white balance adjustment mode.
Peak level detected by a peak level detection circuit (not shown).
The first comparison reference PK is set based on the bell
On the other hand, it is lower by a predetermined level than the first comparison reference PK.
The level is set to the second reference LOW
Have been. As a result, in the comparison circuits 70 and 72
Is the range from the first to the second comparison standard, and within this range
Area with a brightness level of
It is output as the default LVGT. Thus gate signal generation
In the circuit 68, the first and second comparison references PK
And LOW, the luminance signal ADY
Generates various gate signals LVGT based on signal level
It is made to be able to do. Further, in the gate signal generation circuit 68,
Is the same as applying the vertical synchronization signal VD to the V counter 74.
And a horizontal synchronizing signal to the V counter 74 and the H counter 76.
Give HD. The V counter 74 uses the vertical synchronization signal VD
After resetting the count value, the horizontal synchronization signal HD is sequentially output.
Count, which allows raster scanning in the vertical scanning direction.
A count value indicating the inspection position is output. In contrast, H
The counter 76 resets the count value with the horizontal synchronization signal HD.
After that, the specified clock signal is counted sequentially,
Indicates the raster scanning position in the horizontal scanning direction by
Output the event value. The comparison circuit 78 has two comparison references UP and
The count value of the V counter 74 is
The output signal falls within the range of the two comparison criteria UP and DWN.
Signal level in the vertical scanning direction.
The signal level rises at a given raster scanning position.
Generate a gate signal. Similarly, two comparison circuits 80
H counter based on the comparison reference LFT and RGT
The count value of 76 is a comparison between the two comparison standards LFT and RG.
When it enters the range of T, the signal level of the output signal rises,
As a result, a predetermined raster scanning position in the horizontal scanning direction is obtained.
Generates a gate signal whose signal level rises. Thus, the gate signal generation circuit 68
Is a type in which the signal level rises in a predetermined area of the captured image.
To generate various gate signals WHGT.
You. Here, the comparison reference U of the comparison circuits 78 and 80
P, DWN and LFT, RGT are the central processing unit 1.
0 so that the gate signal
In the circuit 68, the gate signal is set according to the operation mode.
The timing of WHGT can be switched.
You. The selector 82 determines whether the central processing unit 10
Based on the control signals ARE0-ARE2 output from the
In the self-diagnosis mode etc., the comparison circuit
Gate signal WHGT or block signal output from 78 and 80
While the ranking signal BLK is selectively output,
In the balance adjustment mode, the level gate LVG
Selectively output T. As a result, the gate signal generation circuit 68
For example, by selecting the comparison outputs of the comparison circuits 78 and 80,
The signal level is increased in one desired horizontal scanning period during the blanking period.
While the gate signal GT1 at which the signal rises can be output.
The comparison output of the comparison circuit 78 is selected, and the signal
Be able to output the gate signal GT1 where the bell rises
It has been done. In this embodiment, the gate signal generation
The circuit 68 outputs the selection output of the selector 82 to the gate circuit 86
, Where the output from the central processing unit 10 is
In response to the mode switching signals MSL0 to MSL2,
From the selected output, the first and second gate signals CLR and LC
H is generated. This allows the gate signal
In the signal generation circuit 68, this gate
Adjustment signals by selectively using the gate signals CLR and LCH.
Simplifies the work and allows you to check the operation mode, etc.
Has been made. (5) Level Detection Circuit As shown in FIG. 5, the level detection circuit 90
Various signals are detected based on T1.
As a result, in white balance adjustment mode,
Check the signal level difference between the red and blue color signals with respect to the color signal.
Put out. That is, the level detection circuit 90 outputs the color signals SR
To SB to the selector 92, and the selection signal is latched
Output via a path 94. Here, in the selector 92, the central processing
The contact is set based on the control signal output from the unit 10.
Switching, which in this embodiment is a selector 9
2 contact points to switch the signal level of each color signal SR-SB
Can be detected. This allows the selector
Reference numeral 92 denotes a feed in the white balance adjustment mode.
Switch the contacts in units of red, red signal SR and blue
Select and output signal SB alternately in field units
It has been done. Adjustment mode and self-diagnosis mode
In the field, the contacts are sequentially switched in units of fields,
Thus, the respective color signals SR to SB are sequentially and cyclically output.
It has been made like that. In the selector 92, the color signal
Inputs the output signal of the counter circuit 96 in addition to SR to SB
So that the color signals SR to SB can be replaced.
To select and output the reference signal that rises in three field cycles
Have been made to gain. The gate circuit 96 has a gate signal
During the period during which the signal level of signal GT1 rises, the selector
The selected output of 92 is output to the latch circuit 98,
In the white balance adjustment mode, the white balance
The color signals SR and SB of the color adjustment area are selectively output. On the other hand, self-diagnosis mode and adjustment mode
, The gate circuit 96 similarly controls the gate signal GT1
During the period when the signal level of the latch circuit 94 rises.
An output signal is transmitted, whereby each of the color signals SR to SB is output.
Video during one horizontal scanning period during the vertical blanking period
A signal for a period or the like is selectively output. The gate circuit 100 includes a latch circuit 102
Receives the green signal SG via the gate signal GT1
During the period when the level rises, this green signal SG is
The signal is selectively output to the touch circuit 104. The subtraction circuit 106 is connected to the selector 10
Outputs of latch circuits 98 and 104 via 8 and 110
And outputs the subtraction output to the addition circuit 112.
You. As a result, in the white balance adjustment mode,
The level detection circuit 90 subtracts the green signal from the red signal.
The first subtraction signal obtained by the calculation and the blue color signal to the green color signal
Signal and a second subtraction signal obtained by subtracting the
The output is made alternately. In contrast, the adjustment mode and the self-diagnosis mode
The selector 110 determines the signal level of the output signal.
To the 0 level, thereby reducing the subtraction circuit 106.
The arithmetic processing is stopped and controlled, for example, data for black level adjustment.
Data can be detected. Note that level detection
In the circuit 90, in addition to the output signal of the latch circuit 98,
To input a predetermined subtraction output to the selector 108.
Then, by switching the contact of the selector 108,
The signal level of this subtraction output can be detected.
I have. The adder circuit 112 is connected via an AND circuit 114
And outputs an output signal to the latch circuit 116.
The output signal of the circuit 116 is fed back as an addition input. here
In the AND circuit 114, white balance adjustment
In the mode, the clear signal C is synchronized with the vertical synchronization signal.
LR is inputted, whereby the addition circuit 1
At 12, the output of the selector 108 is output in the field cycle.
The force signals are cumulatively added. Thereby, the level detection circuit 90
, White rose via the latch circuit 116
Red and blue for the green signal in the sense adjustment area
The signal level differences of the color signals are cumulatively added in the field cycle.
It has been made. In contrast, the self-diagnosis mode and the adjustment mode
In the mode, the subtraction processing of the subtraction circuit 106 is controlled to stop.
As a result, during the period when the gate signal GT1 rises,
Field unit for each color signal SR to SB
Is used to obtain the signal level cumulative addition result.
You. The selectors 118 and 120 are respectively
The contacts are switched at the yield cycle, and the latch
The circuits 122 and 124 are respectively
The accumulation result of the touch circuit 116 is latched. This
In the level detection circuit 90, the white balance
Adjustment mode, the white balance adjustment area
Signal level difference between red and blue signals with respect to green signal
The cumulative addition results are stored in latch circuits 122 and 124, respectively.
To the central processing unit 10
Output to As a result, in the imaging device 1,
Set the white balance so that the result of product addition becomes 0 level.
adjust. On the other hand, in the adjustment mode, the level
The detection circuit 90 detects the period during which the gate signal GT1 rises.
For each color signal between them, the cumulative addition result of the signal level
Are sequentially and cyclically accumulated in the latch circuits 122 and 124.
In this embodiment, the imaging device 1
Each circuit block is adjusted based on the product addition result. In the self-diagnosis mode, the AND circuit
The clear signal CLR input to 114 is a vertical blank
Of the test signal TS inserted during the
It is made to rise at the rise of the video period.
In response, latch circuits 122 and 124 respectively
Based on the rising timing of each clear signal CLR
The accumulated sum of the signal levels
ing. Thereby, in the imaging device 1, the latch circuit
Based on the cumulative addition result stored in
Monitor the test signal inserted during the
Based on the cumulative addition result stored in the circuit 124, the video
The signal level during the period is detected, so that, for example, the aperture 6 is
It is possible to detect circuit block abnormalities while controlling.
Have been. Further, in this embodiment, the level detection
The path 90 is connected to a flip-flop circuit (FF) 126.
The output signal of the switch circuit 98 is supplied, thereby
For example, white balance adjustment via the tip circuit 126
In the mode, within the white balance adjustment area,
Detection that the signal level rises for each pixel of the solid-state imaging device 2
Generate output. The counter 130 is provided via the selector 128
Receiving the signal of the flip-flop circuit 126,
By counting this output signal at the gate period,
The number of pixels during a period when the trigger signal GT1 rises.
You. Thus, in the imaging device 1, the latch circuit 12
The cumulative addition result of 2 and 124 is counted by the counter 130.
The signal level in 1-pixel units.
It has been made available. In this embodiment, the selector 128
Switches contacts based on a predetermined control signal CSL.
As a result, the level detection circuit 90 adjusts the white balance.
In operation modes other than the
It is configured to output a count result. With the switching of the operation of the selector 128,
In the selector 128,
To input the output signal of the latch circuit 98,
In the comparison circuit 132, the central processing unit 10
Latch circuit 9 based on comparison reference PRK set by
8 to output a comparison result for the output signal of
ing. As a result, in the level detection circuit 90,
Set various reference levels as necessary, and
The number of pixels of each color signal exceeding
ing. (6) Central Processing Unit Here, the central processing unit 10 assembles the image pickup apparatus 1.
During maintenance, a system input via a specified jig
The operation is switched based on real data, and
The mode switches to the adjustment mode. In this state, the central processing unit 10 continues
According to each adjustment item based on the control data input
Execute the processing program to automatically adjust each adjustment item.
To adjust. (6-1) Black Set Adjustment Here, as shown in FIG. 6, in the black set adjustment,
The central processing unit 10 starts from step SP1.
After moving to SP2 and closing the aperture 6, step SP
Move to 3. Here, the central processing unit 10 receives the gate signal.
And outputs a control signal to the
Set quasi-LFT, RGT, UP, DWN and
The contact of the collector 82 is switched. This allows the central processing unit
The nit 10 has a signal level rising in the effective area of the captured image.
A rising gate signal GT1 is generated, followed by step SP
Move to 4. Here, the central processing unit 10 has a latch
The accumulated addition results latched on the paths 122 and 124 are taken.
After that, the accumulated addition results are respectively stored in the counters 130.
Divide by the count value of. That is, in the imaging device 1
Because the aperture 6 is completely closed,
Counter of the cumulative addition result of the latch circuit 122 or 124
Divided by the count value of 130, the black level
Can be detected. At this time, the central processing unit 10
Accumulated in the latch circuits 122 and 124 in units of fields
The result of the addition is latched, so that the color signal
Black level for even and odd fields
To detect. That is, in the output signal of the solid-state imaging device,
Indicates that the black level may fluctuate between
In the case of, it is necessary to switch and adjust the black level for each field.
It is necessary. For this reason, the central processing unit 10 has an even number
Field and the odd field
The black level is corrected based on this detection result. When this detection result is obtained, the central processing unit
Step 10 moves to the following step SP5, where the encoding is performed.
So that the black level of the color signal output to the
Then, the correction data DP is generated, and the correction data DP is
The output is output to the adder circuit 140 for setting the destal level. This
Here, as shown in FIG. 7, each of the color signals SR to SB is an AV block.
In the circuit 16, a black level shift is performed by the addition circuit 132.
After the edging correction signal SH1 is added, the gain
The signal is amplified by the amplifier 134, and the white level is then
Is multiplied by the shading correction signal SH2. Further, the color signals SR to SB are
Converted into a digital signal by the digital conversion circuit 18
Thereafter, the flare correction signal DF is multiplied by the multiplication circuits 42R to 42B.
The video processing circuit 2 calculates
The pedestal level is set by the adder circuit 140 of FIG.
It has been done. Here the central processing unit 10
Is set based on the black level detection result.
The correction data DP is generated by correcting the
By adding DP to the color signal by the addition circuit 140,
Set black level along with pedestal level
This automatically adjusts the black level with a simple configuration
I do. At this time, the central processing unit 10 stores
Black level detection between the yield and odd fields
By switching the correction data DP based on the output result
To compensate for changes in black level that occur between fields.
Correct. That is, this variation is repeated in the field cycle.
By being returned, for example, in the state of an analog signal
Cannot completely compensate for this variation. However, this practice
Change the correction data DP as in the example to prevent fluctuation
To ensure that black levels do not fluctuate between fields.
Can be. Subsequently, the central processing unit 10 performs this correction.
After storing the contents of data DP in the memory circuit, step
Move to SP6, where black level is set for all color signals.
Is determined. In this case, a negative result
As a result, the central processing unit 10
Move to 7, switch the channel and return to step SP4
You. This causes the central processing unit 10 to execute step SP.
The processing loop of 4-SP5-SP6-SP7-SP4 is repeated.
When the black level is corrected for all the color signals,
When a positive result is obtained in step SP6,
Then, the process proceeds to step SP8. Here, the central processing unit 10 is used for all
Determine whether you have set a black level for the profit, in this case
When a negative result is obtained, the process proceeds to step SP9.
The gain of the gain amplifier 134 is switched. Ie
In this embodiment, the imaging device 1 operates a predetermined operation element.
Amplifies color signals compared to normal operating conditions
The ratio can be switched in two steps in 6 [dB] units.
So that the brightness of the entire screen can be increased.
It has been done. Therefore, the offset voltage is supplied to the addition circuit 132 and the like.
If there is pressure, the black level
Also fluctuate. For this reason, in this embodiment, the central processing unit
Tut 10 adjusts the black level for each gain, and adjusts the correction data.
After the contents of the data DP are stored in the memory circuit, step S
The process moves to P10, and this processing procedure ends. This allows
The central processing unit 10 stores the correction data stored in the memory circuit.
Correction data for each gain in the operating state based on the contents of the data DP.
Data DP, thereby changing the black level of each color signal.
Correct and adjust the black set. At this time, the central processing unit 10
Sets the black level of each color signal to a predetermined reference level
By adjusting the black balance
It has been done. (6-2) Setting of White Balance Here, the central processing unit 10 adjusts the white balance.
In the mode, the processing procedure shown in FIG.
Adjust the balance. That is, the central processing unit 10
, The white balun placed on the operation panel
When the operator for starting the process adjustment is turned on, step SP
The process moves from step 11 to step SP12, where the operation of the entire
After setting the operation mode to white balance adjustment mode,
The peak level detection result is obtained from the peak level detection circuit 56.
input. Subsequently, the central processing unit 10 executes a step
Moves to SP13, where the comparison of the gate signal generation circuit 68 is performed.
Set the reference PK and LOW. This allows the central processing unit
In the nit 10, based on the peak level detection result
To set the white balance adjustment area
I have. Subsequently, the central processing unit 10 executes a step
Moves to SP14, where the control signal is sent to the level detection circuit 90.
Is output, and the selector 108 etc.
After setting the mode, the process proceeds to step SP15. Here inside
The central processing unit 10 is connected to the latch circuits 122 and 124.
The accumulated addition result is counted by the counter 130.
And then set the accumulated value to 0 level
Then, the correction data for adjusting the amplification factor is generated. Subsequently, the central processing unit 10 executes a step
Moves to SP16 and corrects the amplification factor adjustment data for AV
And outputs a red signal and a blue signal
Switch the signal amplification rate and adjust the white balance
You. Thus the red and blue signals for the green signal
By detecting the signal level difference before gamma correction,
White balance deviation with high accuracy.
High white balance adjustment based on the result
White balance can be adjusted with precision. Thus, the central processing unit 10 is
When the balance is adjusted, it is output to the AV block circuit 16.
The corrected data is stored in the memory circuit. At this time
The logical unit 10 is stored in the first memory space in advance at the time of factory shipment.
The correction data for the standard color temperature set in
In addition to the first memory space, a second
3 memory spaces are prepared. this
Central processing unit 10 adjusts white balance
Second or third memory space in response to user operation at the time
To store the correction data. As a result, the
The correction data in the second and third memory spaces.
By outputting to the AV block circuit 16 instead,
First and second white balance adjustment modes can be selected.
The white balance adjustment mode.
In other words, for example, chasing the subject to be imaged
Even if you move the shooting site indoors,
Easy white balance adjustment following color temperature changes
It has been made. Further, the central processing unit 10
When the correction data for the balance adjustment is obtained,
Move to step SP17, where the AV
Correction for the black set based on the gain of the
The data DP is detected. This detection process
Performance based on the gain correction data obtained by
The central processing unit 1 is executed by applying the arithmetic processing method.
0 indicates that the result of this arithmetic processing is a complement for white balance adjustment.
Stored in the second or third memory space corresponding to the positive data
Then, the process proceeds to step SP18 to end this processing procedure.
You. As a result, the central processing unit 10
And the second white balance adjustment mode
Select and output the first and second correction data DP for the preset
To switch the gain for white balance adjustment
To compensate for fluctuations in black balance due to. This
In the imaging apparatus 1, the white balance adjustment mode is set to
Even when switching, it prevents variations in the black set.
As a result, the quality of the captured image can be improved accordingly. (7) Effects of the Embodiment According to the configuration described above, the white balance adjustment mode
First and second correction data D for the corresponding black set
P is stored in the memory circuit and white balance adjustment mode
In response to the switching of the first and second correction data
By selectively using it to compensate for black balance.
Black balance when switching white balance adjustment.
The lance change can be compensated, thereby improving the quality of the captured image.
Can be improved. (8) Other Embodiment In the above embodiment, the pedestal level setting
Correction data DP and black balance adjustment
However, the present invention is not limited to this,
Correct the correction data DF to adjust the black balance
You may. That is, in the flare correction data,
When the value of the correction data DF changes according to the amount of light,
Based on the black level detection result, the correction data DF
Offsets the black level to a predetermined level.
Set to. Even in this way, white balance adjustment
Select and output the correction data corresponding to the mode, and
White balance by adjusting the black balance
Changes in black balance due to switching of balance adjustment
Can be corrected. Further, in the above embodiment, the pedestal
The correction data DP for setting the
The case of adjusting the lance was described, but instead
Corrects the DC level of the editing correction signal SH and
The work balance may be adjusted, and the AV block may be adjusted.
Addition dedicated to circuit 16, digital signal processing circuit 20, etc.
Circuit to correct the black level of the color signal and
The rack balance may be adjusted. Further, in the above-described embodiment, the black level
Although the case of automatically adjusting the
However, when adjusting by manually inputting correction data, etc.
It can be widely applied in such cases. Further, in the above-described embodiment, the imaging screen
Automatically detects the black level in the effective area of
However, the present invention is not limited to this.
When detecting and adjusting the black level for the video period,
In addition, a predetermined area is set in the effective area, and black is set in this area.
It can be widely applied, for example, when detecting a level. Further, in the above embodiment, each color signal
The black level of the camera is adjusted to the predetermined reference level
As described above, the present invention is not limited to this.
The black level of the red and blue color signals is
By adjusting the black balance,
Good. Further, in the above embodiment, the white
Black balance supplement for balance adjustment mode
Described the case of generating positive data by arithmetic processing
However, the present invention is not limited to this.
When the correction data is detected by executing the processing procedure shown in FIG.
Test signal during the horizontal and vertical blanking periods
The test signal of the generation circuit 30 is inserted, and the test signal
When generating correction data based on the signal level detection result
For example, various production methods can be widely applied. As described above, according to the present invention, white
For black balance adjustment corresponding to balance adjustment mode
Of the white balance adjustment mode
Selectively use to compensate for black balance in response to movement
To change the white balance adjustment.
To obtain an imaging device capable of correcting a change in black balance
be able to.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an imaging apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram showing the digital signal processing circuit. FIG. 3 is a block diagram showing a peak level detection circuit. FIG. 4 is a block diagram showing a gate signal generation circuit. FIG. 5 is a block diagram showing a level detection circuit. FIG. 6 is a flowchart for explaining adjustment of a black level. FIG. 7 is a block diagram for the explanation. FIG. 8 is a flowchart for explaining white balance adjustment. DESCRIPTION OF SYMBOLS 1... Imaging device 2... Solid-state imaging device 10... Central processing unit 16... AV block circuit 20... Digital signal processing circuit 50. .., A data detection circuit, 56, a peak level detection circuit, 68, a gate signal generation circuit, 90, a level detection circuit.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 9/72-9/73 H04N 9/04

Claims (1)

(57) Claims: 1. An image pickup means for picking up an image of a desired subject and outputting a color signal, amplifying and outputting the color signal, and setting a gain based on predetermined gain control data. A signal processing circuit for switching; a signal level detection circuit for detecting a signal level of the color signal; and outputting a signal level detection result; and outputting the gain control data based on the signal level detection result; A white balance setting circuit for setting a balance, a signal level correction circuit for correcting the black level of the color signal based on predetermined signal level correction data, and a correction data output circuit for outputting the signal level correction data. The white balance setting circuit has first and second white balance setting modes, and switches the gain control data in response to an operation of a predetermined operation element. By changing the output, the gain of the signal processing circuit is set to the gain of the first and second white balance setting modes, and the correction data output circuit is set to the first and second white balance setting modes. An image pickup apparatus, wherein the correction data is switched and output in accordance with the correction data.