JPH11298768A - Image photographing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control an image-pickup means and an image processing means according to detected image information of signal level with control conditions which are equivalent to those in a monitoring mode, even in an all-pixel read-out mode. SOLUTION: This device is equipped with an image-pickup means 1, having N-line × M-pixel photoelectric conversion elements D11 to DNM for receiving light L from a subject 30 and to output image information of all the pixels of the subject 30; an operation means which indicates an all-pixel read-out mode in which the image information of all the pixels is read out of the image- pickup means 1 or a monitoring mode in which the image information of all the pixels is read out by every (n) lines; an image processing means 2 which detects the optical feature quantity of the subject 30 from the image information and outputs a luminance detection signal S1 and a white balance detection signal S2; and a control means 3 which controls the input and output of the image-pickup means 1 according to a shutter signal S2 outputted from the operation means, and when indication is switched from the monitoring mode to the all-pixel read-out mode, the signal level of the image detection information of the image processing means 2 is set to 1/n.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image photographing apparatus suitable for use in a digital still camera, a video camera, a surveillance camera, and the like having a monitoring function using an all-pixel readout solid-state imaging device.

More specifically, image information of all pixels of a subject is represented by n
When switching from the monitoring mode for reading each line to the all-pixel reading mode for reading image information of all pixels, the signal level of image detection information such as the brightness and color of the subject is reduced to 1 / n, and in the all-pixel reading mode, Also,
The input and output of the imaging means and the image processing means can be controlled based on the image detection information of the signal level which is equivalent to the control condition in the monitoring mode.

[0003]

2. Description of the Related Art In recent years, digital still cameras have often been used in the field of image processing capable of editing and recording still images. This type of digital still camera uses an all-pixel readout solid-state imaging device, a monitoring mode that displays a moving image on a monitor to determine the composition of a still image of the subject, and stores the still image in a flash memory or the like. All pixel readout mode is prepared in advance.

Normally, when a digital still camera is used in a monitoring mode and a still image is stored in a flash memory or the like, it is handled to execute an all-pixel reading mode.

[0005]

According to the digital still camera provided with the solid-state image pickup device of the all-pixel readout method, in the monitoring mode, out of the image information of one frame constituting one screen, every n lines There are pixels to be read and pixels not to be read. Further, the output of the solid-state imaging device is input to the next-stage image processing circuit, and the detection value detected by the image processing circuit is used as it is as a control value of the solid-state imaging device and the image processing circuit.

For this reason, at the time when the mode is switched from the monitoring mode to the all-pixel reading mode, the control system sends an n-fold detection value (hereinafter also referred to as image detection information) from the image processing circuit.
And the solid-state imaging device (hereinafter, also referred to as an imaging unit) and an image processing circuit (hereinafter, also referred to as an image processing unit) are controlled based on the brightness and color information multiplied by n. .

By the way, if the digital still camera does not use the monitoring mode but decides the composition of the still image of the subject only in the all-pixel reading mode, 1 /
The moving image of the subject is updated every 30 seconds (normally 1/60 seconds). For this reason, the moving image fluctuates on the monitor and becomes very difficult to see.

In view of the above, the present invention solves such a conventional problem. In the all-pixel reading mode, the imaging means is controlled based on signal level image detection information having control conditions equivalent to those in the monitoring mode. It is an object of the present invention to provide an image photographing apparatus capable of controlling image processing means and image processing means.

[0009]

An object of the present invention is to provide an image pickup device having an N-line × M-pixel photoelectric conversion element for receiving light from a subject and outputting image information of all pixels of the subject. Operating means for instructing either an all-pixel reading mode for reading image information of all pixels from the imaging means or a monitoring mode for reading image information of all pixels from the imaging means every n lines; Image processing means for detecting the optical characteristic amount of the image and outputting image detection information, and controlling input / output of the imaging means based on the image detection information by the image processing means and the mode instruction information outputted from the operation means. Control means,
An image photographing apparatus characterized in that the control means reduces the signal level of image detection information by the image processing means to 1 / n at least when an instruction is switched from the monitoring mode to the all-pixel reading mode by the operation means. Solved by

According to the present invention, for example, when the signal level of the image detection information relating to the brightness of the subject in the monitoring mode is A, and when the mode is switched from the monitoring mode to the all-pixel reading mode, the image is not changed. Although the signal level of the detection information is n times × A, since the signal level of the image detection information is set to 1 / n,
Also in the all-pixel reading mode, it is possible to perform feedback control on the aperture of the imaging unit, the gain of the image processing unit, and the like based on the image detection information at the signal level A, under which the control conditions are equivalent to those in the monitoring mode. Therefore, the all-pixel readout type image photographing device having the monitoring function can be sufficiently applied to digital still cameras, video cameras, surveillance cameras, and the like.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of an image photographing apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a configuration example of an image photographing apparatus 100 according to the present embodiment. In the present embodiment, when the mode is switched from the monitoring mode in which the image information of all the pixels of the subject is read every n lines to the all-pixel reading mode in which the image information of all the pixels is read, at least image detection relating to the brightness and color of the subject is performed. The signal level of the information is set to 1 / n, so that the input / output of the imaging means can be controlled based on the image detection information of the signal level at which the control conditions are equivalent to the monitoring mode.

This image photographing apparatus 100 is an all-pixel readout type image pickup means (PS-CCD: Progressive) shown in FIG.
ve Scan CCD Image Sensor 1. The imaging means 1 has an aperture 11, a solid-state imaging device unit 12, and a sample-hold & analog-to-digital conversion circuit (hereinafter referred to as an S / H & A / D conversion circuit) 13.

An aperture (iris) 11 adjusts the amount of light from the subject 30 and has a galvanometer type aperture mechanism. A lens unit (not shown) is provided in front of the diaphragm 11, and a lens unit is provided behind the lens unit.
Light L from the subject 30 is imaged. A solid-state imaging device unit 12 is provided behind the aperture 11, and the light L of the subject 30 whose light amount is adjusted by the aperture 11 is incident thereon, and an image acquisition signal Sin is obtained as image information of all pixels of the subject 30.
Is output. The solid-state imaging device unit 12 includes, for example,
N lines × M pixels of photoelectric conversion elements (sensors) D11 to D
ij (i = 1 to N, j = 1 to M).

The output stage of the solid-state imaging device unit 12 has S
/ H & A / D conversion circuit 13 is connected, and the image acquisition signal S
in is held in a capacity not shown. After the voltage held in this capacitor is converted into a digital signal, it becomes image data Dout. The image processing means 2 is connected to the output stage of the S / H & A / D conversion circuit 13, and the image data Dou
The optical characteristic amount of the subject 30 is detected from t, and image detection information is output. In this example, the optical feature amount is image information on at least the brightness and color of the subject 30.
The image processing means 2 includes a brightness detection circuit 14 and a color detection circuit 1
Five. In the brightness detection circuit 14, the image data D
Based on out, a luminance detection signal S1 indicating the exposure state of the subject 30 is detected. In the color detection circuit 15, the image data D
For example, a white balance detection signal S2 indicating the color adjustment state of the subject 30 is detected based on out.

The control means 3 is connected to the image processing means 2. An operation unit 4 is connected to the control unit 3, and image data Dout of all pixels is output from the solid-state imaging device unit 12.
Readout mode or unit 12 for reading out
Is operated so as to instruct any one of the monitoring modes in which the image data Dout of all the pixels is read out every n lines. The operation means 4 is operated by a user. In this example, an instruction is given to the control unit 3 by the operation unit 4 so as to capture a moving image of the subject 30 at a certain moment as a still image. This instruction is the shutter signal S3, and is also a signal for switching the monitoring mode to the all-pixel reading mode.

The control means 3 controls the aperture 11, the solid-state image pickup device unit 12, and the brightness detection circuit 14 based on the luminance detection signal S1, the white balance detection signal S2 from the image processing means 2 and the shutter signal S3 output from the operation means 4.
And the input and output of the color detection circuit 15 are controlled. For example, at least when the instruction is switched from the monitoring mode to the all-pixel reading mode by the operation unit 4, that is, when the shutter is pressed, the control unit 3 controls the brightness detection signal S1 and the white balance by the image processing unit 2. The signal level of the detection signal S2 is set to 1 / n. For 1 / n of this signal level, a divider circuit or the like is used in hardware. In software, a calculation for reducing the signal level to 1 / n is executed on a program.

In this example, the control circuit 3 compares the luminance detection signal S1 with a reference value obtained by calibrating a predetermined appropriate exposure amount, and performs control such that the aperture 11 is automatically exposed. An iris drive circuit 4 is connected to the output stage of the control means 3, and an iris drive control signal S4 from the control means 3
Is used to adjust the amount of light passing through the aperture 11. Further, a timing generation circuit 5 is connected to an output stage of the control means 3, and a transfer clock signal for charge transfer and the like are generated based on a read control signal S 5 from the control means 3.
The brightness detection circuit 14 and the color detection circuit 15 are controlled based on the gain adjustment signal S6 from the control means 3, and control conditions are made equivalent in the monitoring mode and the all-pixel reading mode.

A memory controller or the like (not shown) is connected to an output stage (next stage) of the image processing means 2, and a recording medium such as a disk (hereinafter simply referred to as a memory) is connected to the memory controller. Then, still image data relating to the still image captured by the operation unit 4 and the control unit 3 is recorded in the memory.

Next, referring to FIG.
00 will be described. FIG. 2 is a control flowchart illustrating an operation example of the image photographing apparatus 100. In this example, image information of the subject 30 is
A monitoring mode for reading and displaying for each field and an all-pixel reading mode for reading out one frame of image information of the subject 30 and recording a still image are prepared. Usually, the image capturing apparatus 100 uses the monitoring mode as a reference. It is working.

In the monitoring mode, image detection information having a signal level of 1/2 of all pixels is used.
Therefore, in the all-pixel reading mode, image detection information having a signal level twice as high as that in the monitoring mode is obtained.
In order to avoid the control based on the signal level, the signal level of the image detection information is halved when the mode is switched from the monitoring mode to the all-pixel reading mode.

On the premise of this, in the flowchart shown in FIG. 2, first, in step P1, image detection information is input from the image processing means 2 to the control means 3. As image detection information, a brightness detection signal S1 is output from the brightness detection circuit 14 to the control means 3, and a white balance detection signal S2 is output from the color detection circuit 15 to the control means 3.

Thereafter, in step P2, it is determined whether or not the all-pixel reading mode is instructed by the control means 3.
The all-pixel reading mode is instructed by an operation such that the user presses a shutter button as the operation means 4. Therefore, when the user presses the shutter button or the like, the control unit 3 determines that the mode has been switched from the monitoring mode to the all-pixel reading mode. In this case, the process proceeds to step P3, where the detection values (signal levels) of the luminance detection signal S1 and the white balance detection signal S2 from the image processing means 2 are reduced to 1/2. For a half of the detection value, a division circuit or the like is used.

Thereafter, the process proceeds to step P4, where control values such as an aperture drive control signal S4, a read control signal S5, and a gain adjustment signal S6 are calculated from detection values such as the luminance detection signal S1 and the white balance detection signal S2. In step P5, the control means 3 controls the aperture driving circuit 4, the timing generation circuit 5, and the image processing means 2 based on these control values.
Are controlled, the aperture 11, the solid-state imaging device unit 1
2. The brightness detection circuit 14 and the color detection circuit 15 are optimally adjusted.

If it is determined in step P2 that the user's instruction is not in the all-pixels readout mode, that is, if the normal monitoring mode is to be continued, the process shifts to step P4 and is based on the detected value as it is. After the control value is calculated in step P5, the aperture drive circuit 4 and the timing generation circuit 5
The image processing means 2 and the like are controlled, and the aperture 11, the solid-state imaging device unit 12, the brightness detection circuit 14, and the color detection circuit 15 are adjusted optimally.

As described above, according to the image photographing apparatus 100 of the present embodiment, when the signal level of the image detection information relating to the brightness of the subject in the monitoring mode is set to A, all the pixels are switched from the monitoring mode in step P2. When the mode is switched to the reading mode, the signal level of the image detection information becomes 2 × A as it is, but since the signal level of the image detection information is reduced to 、, even in the all pixel reading mode, Aperture 11, based on image detection information of signal level A equivalent to that in the monitoring mode,
The solid-state imaging device unit 12, the brightness detection circuit 14, and the color detection circuit 15 can be feedback-controlled.
Thus, the image capturing apparatus 100 of the all-pixel readout type having the monitoring function can be sufficiently applied to a digital still camera, a video camera, a monitoring camera, and the like.

Next, an example of the configuration of the solid-state image pickup device unit 12 of the all-pixel readout method will be described. In this example, N × M photoelectric conversion elements D11 to D
ij (i = 1 to N, j = 1 to M) are arranged in a matrix.

In the solid-state image pickup device unit 12, for example, M photoelectric conversion elements D11 to D1M are arranged in the horizontal direction, and N lines of photoelectric conversion element rows are arranged in the vertical direction. Photoelectric conversion elements D11 to D arranged in a vertical direction
A register R1 for vertical transfer is arranged on the right side of N1.
A register R2 for vertical transfer is disposed on the right side of the photoelectric conversion elements D12 to DN2, and similarly, the photoelectric conversion elements D1M to D1
A register RM for vertical transfer is arranged on the right side of the NM. Each of the registers R1 to RM is supplied with a transfer clock signal ΦV for transferring charges in the vertical direction.

A register 7 for horizontal transfer is connected to the last stage of each of the registers R1 to RM, and the charges transferred in the vertical direction are serially read out in the horizontal direction based on the transfer clock signal ΦH. The charge detection unit 8 is connected to the output stage of the register 7 for horizontal transfer, and outputs an image acquisition signal Sin based on the charge readout pulse signal XSG. An amplifier 9 is connected to the output stage of the charge detection unit 8, and the image acquisition signal Sin is amplified and output.

A timing generating circuit 5 is connected to the register 7 and the charge detecting section 8, and a transfer clock signal Φ generated based on a read control signal S5 from the control means 3.
V, ΦH and the charge readout pulse signal XSG are output.

If the odd lines of the pixels read by the solid-state image sensor unit 12 are O1 to O (N / 2) and the even lines are E1 to E (N / 2), the field read is executed in the monitoring mode. Therefore, electric charges are transferred from the vertical transfer registers R1 to RM to the horizontal transfer register 7 in field units, and one line of image information is generated by the sum of odd and even lines. That is, (O1 + E1), (O2 + E2), (O3 + E3)... In the odd field period of 1/30 second.
.. in the subsequent 1/30 second even field period (E1
+ O2), (E2 + O3), (E3 + O4)...

On the other hand, in the all-pixel read mode, the frame read is executed, so that each photoelectric conversion element D1 in the odd-numbered column is read.
1 to DN1 are read out to the vertical transfer register R1 once per frame, and similarly, the charges from the photoelectric conversion elements D21 to DN2 are read out once per frame. To the register R2. In other words, O1, O2, O3,...
Image information of only odd lines is read out,
In the following even field period, E1, E2, E3,.
Thus, the image information of the even line is read.

Next, a digital still camera 200 to which the image photographing apparatus 100 according to the embodiment is applied will be described. FIG. 4 is a block diagram illustrating a configuration example of the digital still camera 200.

This digital still camera 200 has a lens unit 21 having a focus unit and an aperture 11 shown in FIG. A CCD 22 as the solid-state imaging device unit 12 having an electronic shutter is provided at a stage subsequent to the lens unit 21. An S / H & A / D conversion circuit 13 is connected to an output stage of the CCD 22, and an image acquisition signal Sin by the CCD 22 is held in a capacity (not shown) or the like. After the voltage held in this capacitor is converted into a digital signal, it becomes image data Dout.

The output stage of the S / H & A / D conversion circuit 13 includes an automatic focus detection unit (Ato Focus; hereinafter referred to as an AF detection unit) 24 and an automatic exposure detection unit (Ato Expose; hereinafter A).
Automatic white balance detection unit (hereinafter referred to as AWB detection unit) 25;
26 and an RGB gain correction unit 27 are connected. The AF detection unit 24 generates a focus detection signal S0 based on the image data Dout. In the AE detection unit 25, the image data Dou
A luminance detection signal S1 is generated based on t. The AWB detector 26 generates a white balance detection signal S2 based on the image data Dout.

AF detector 24, AE detector 25 and AW
A one-chip microcomputer (hereinafter simply referred to as a control microcomputer) as a control means 3 is provided at an output stage of the B detection unit 26.
45 is connected, and control of the entire camera is performed. For example, the image data Dout is compared with a preset reference value obtained by calibrating an appropriate exposure amount, and control for automatically exposing the aperture of the lens unit 21 is performed, and processing for returning from the all-pixel reading mode to the monitoring mode is performed. Is executed.

In addition, the control microcomputer 45 creates a focus control signal S9 from the focus detection signal S0, creates an aperture drive control signal S4 and a readout control signal S5 from the luminance detection signal S1, and creates an R signal from the white balance detection signal S2.
A GB gain correction control signal S7 is created. The RGB gain correction control signal S7 is output to the RGB gain correction unit 27, and the color temperature of the image is corrected based on the signal S7.

A memory controller 28 is connected to an output stage of the RGB gain correction section 27, and controls recording or storing of the image data Dout and display control of a moving image and a still image based on the image data Dout. A display buffer memory 29 is connected to the output stage of the memory controller 28 to store the corrected image data Dout and to store the corrected image data Dout in a liquid crystal display (hereinafter referred to as L
The data is read as raster scan data to be displayed on a CD 41. A digital / analog conversion circuit (hereinafter referred to as a D / A conversion circuit) 40 is connected to an output stage of the buffer memory 29, and after the raster scan data is converted into an analog image signal S 11, the analog image signal S 11 is output to the LCD 41. Then, a moving image or a still image is displayed.

A shutter button (switch) 43 is connected as an operating means 4 to the input stage of the control microcomputer 45, and when this button is pressed, a shutter signal S3 is output to the control microcomputer 45. The control microcomputer 45 recognizes from the shutter signal S3 that recording of a still image has been instructed.

A data compression / expansion circuit 42 is connected to the memory controller 28, and the image data Dout is compressed / expanded. A flash recording block memory (hereinafter simply referred to as flash memory) 44 is connected to the data compression / expansion circuit 42, and a still image is stored when the shutter button 43 is pressed.

Next, the operation of the digital still camera 200 will be described. FIG. 5 is a flowchart showing an example of the control. In this example, the shutter button 43 is connected to the control microcomputer 45, and a moving image of the subject 30 is normally output to the LCD 41 by monitoring in the monitoring mode. Further, when the user presses the shutter button 43, it is assumed that the still image at that time is output to the LCD 41 on the monitor and the still image is stored in the flash memory 44.

First, at step Q1, the control microcomputer 45 waits for a photographing request from the user. If the photographing request has been made, the process proceeds to step Q2 to execute an image acquisition process relating to the monitoring mode. Here, for example, TV
Stable speed feedback loop control is performed on the aperture 11 of the lens unit 21 so that the exposure amount becomes constant during one field time of the signal. As a result, the lens unit 21
The image received through the CCD 22 is converted into an electric signal by the CCD 22.

In this monitoring mode, field reading is performed, so that charges are transferred from the vertical transfer registers R1 to RM shown in FIG. 3 to the horizontal transfer register 7 shown in FIG. It is generated by the sum of an odd line and an even line. That is,
In the odd field period of 1/30 second (O1 + E1),
(O2 + E2), (O3 + E3) ..., followed by 1/3
(E1 + O2), (E2
+ O3), (E3 + O4)... After that, the image information is S / H & A / D
After being digitized by the conversion circuit 13, the image data becomes the image data Dout.

Then, in step Q3, the control microcomputer 45
Is the image data Dout by the S / H & A / D conversion circuit 13
The image processing is executed based on. This image data Dout
Denotes an AF detector 24, an AE detector 25, an AWB detector 26
After the signal processing, a focus detection signal S0, a luminance detection signal S1, and a white balance detection signal S2 are obtained. The control microcomputer 4 receiving these signals S0 to S2
5, a focus control signal S9 is created from the focus detection signal S0, and an aperture drive control signal S4 is created from the luminance detection signal S1.
And a read control signal S5, and an RGB gain correction control signal S7 is generated from the white balance detection signal S2. The control signal S4 is output to the lens unit 21, and the control signal S5 is output to the CCD 22.

Thereafter, in step Q4, the control microcomputer 45
Outputs the moving image to the LCD 41 on the monitor. In this case, RG
The B gain correction control signal S7 is output to the RGB gain correction unit 27. In the RGB gain correction unit 27, the signal S
7, the color temperature of the image is corrected. The image data Dout corrected by the RGB gain correction unit 27 is stored in the buffer memory 29 by the main controller 28. In the buffer memory 29, the data is converted into raster scan data suitable for the LCD 41, and the raster scan data is converted into an analog image signal S11 by the D / A conversion circuit 40. A moving image is displayed on the LCD 41 based on the analog image signal S11.

Thereafter, in step Q5, the control microcomputer 45
Determines whether the power has been turned off by the user as a shooting end command. In this example, since it is assumed that the shutter button 43 is pressed in the monitoring mode, the process proceeds to step Q6.

In this step Q6, the control microcomputer 45 detects whether the user has pressed the shutter button 43. At this time, when the shutter button 43 is pressed, the control microcomputer detects a shutter signal S3. At the same time, the control microcomputer 45 outputs the fetch instruction signal S8 to the memory controller 28. If the shutter button 43 has not been pressed after waiting for a certain period of time, the process returns to step Q2.

If the shutter button 43 has been pressed, the flow shifts to step Q7 to execute image acquisition processing relating to the all-pixel reading mode. In this all-pixel reading mode, frame reading is performed, so that charges from each photoelectric conversion element are read to the vertical transfer registers R1 to RM shown in FIG. 3 once per frame. In other words, O1, O2, O3,...
Image information of only odd lines is read out,
In the following even field period, E1, E2, E3,.
Thus, the image information of the even line is read. After that, the image information is digitized by the S / H & A / D conversion circuit 13 to become image data Dout.

Then, in step Q8, the control microcomputer 45
Is the image data Dout by the S / H & A / D conversion circuit 13
The image processing is executed based on. At this time, the image data D
out, the AF detection unit 24, the AE detection unit 25, the AW
The focus detection signal S0, the luminance detection signal S1, and the white balance detection signal S2 that have been subjected to the signal processing by the B detection unit 26 are calculated by が. Here, in the control microcomputer 45 to which the signals S0 to S2 calculated by 入 力 are input, the focus control signal S9 is created from the focus detection signal S0, and the aperture drive control signal S4 and the readout control signal S5 are created from the luminance detection signal S1. And the white balance detection signal S2
From the RGB gain correction control signal S7. These control signals S4 are output to the lens unit 21, and the control signal S5 is output to the CCD 22.

Thereafter, in step Q 9, the memory controller 28 transfers the image data Dout by the RGB gain correction unit 27 at the time when the shutter button 43 is pressed to the data compression / expansion circuit 42. The image data Dout compressed by the data compression / decompression circuit 42 is stored in the flash memory 44 as a frame still image.

Thereafter, at step Q10, the control microcomputer 4
5 returns the all-pixels reading mode to the monitoring mode, and then returns to step Q2 to continue the image acquisition processing in the monitoring mode. Hereinafter, according to the user's instruction, the control microcomputer 45 performs steps Q3 to Q1.
0 is repeated. If the power is turned off in step Q5, the image shooting control ends.

As described above, according to the digital still camera 200 to which the image photographing apparatus 100 according to the present embodiment is applied, when the signal level of the image detection information relating to the brightness of the subject in the monitoring mode is A, the step When the mode is switched from the monitoring mode to the all-pixel readout mode in Q2, the signal level of the image detection information becomes 2 × A as it is, but the signal level of the image detection information is reduced to １ ／. Also, in the all-pixel readout mode, the lens unit 2 based on the signal level image detection information that makes the control conditions equivalent to those in the monitoring mode.
1, CCD 22, AF detector 24, AE detector 25, A
The WB detection unit 26 and the RGB gain correction circuit 27 can be feedback-controlled. Accordingly, it is possible to provide the digital still camera 200 of the all-pixel readout method having the monitoring function.

Further, the control microcomputer 45 can perform image processing on the detection value in calculation through the all-pixel reading mode and the monitoring mode without being aware of the mode difference. This simplifies the algorithm of the software, improves the reliability of the digital still camera 200, shortens the processing time, and facilitates debugging.

Further, by executing the image processing of the present invention, even when determining the composition of a still image while looking at the LCD 41, the moving image of the subject 30 does not fluctuate, and the movement of the subject 30 is very natural. It is possible to monitor a moving image of the subject 30 with a smooth motion as in the case of an (interline transfer) video camera. Therefore, the composition of the subject 30 when recording a still image can be easily determined.

[0055]

As described above, according to the image photographing apparatus of the present invention, the monitoring mode in which the image information of all the pixels of the subject is read every n lines is switched to the all-pixel reading mode in which the image information of all the pixels is read. At least, the image detection information such as the brightness and color of the subject is reduced by 1 / n.

With this configuration, it is possible to control the input / output of the image pickup means even in the all-pixel readout mode based on image detection information at a detection level equivalent to that in the monitoring mode. Therefore, an all-pixel readout type image photographing apparatus having a monitoring function can be sufficiently applied to a digital still camera or the like.

The present invention is very suitable when applied to a digital still camera, a video camera, a surveillance camera, and the like having a monitoring function using a solid-state image pickup device of an all-pixel readout system.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of an image photographing apparatus 100 according to an embodiment.

FIG. 2 is a control flowchart showing an operation example of the image photographing apparatus 100.

FIG. 3 is a solid-state imaging device unit 1 of an all-pixel readout method.
2 is a block diagram illustrating a configuration example of FIG.

FIG. 4 is a block diagram illustrating a configuration example of a digital still camera 200 to which the image capturing device 100 is applied.

FIG. 5 is a control flowchart showing an operation example of the digital still camera 200.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Imaging means, 2 ... Image processing means, 3 ... Control means, 4 ... Operation means, 11 ... Aperture, 12 ...
・ Solid-state image sensor unit, 13 ・ ・ Sample hold &
Analog-to-digital conversion circuit, 14: brightness detection circuit, 15: color detection circuit, 21: lens unit, 22
... CCD, 24 ... AF detector, 25 ... AE
Detector, 26 AWB detector, 27 RGB gain correction circuit, 28 Memory controller, 29
..Buffer memory, 40... D / A conversion circuit, 41
... LCD, 42 ... data compression / expansion circuit, 43
... Shutter button, 44 ... Flash memory, 45 ... Control microcomputer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04N 5/92 H04N 5/92 H

Claims (4)

[Claims] 1. An image pickup means having a photoelectric conversion element of N lines × M pixels for receiving light from a subject and outputting image information of all pixels of the subject, and an image of all pixels from the image pickup means. Operating means for instructing either an all-pixel reading mode for reading information or a monitoring mode for reading image information of all pixels from the imaging means for every n lines; and an optical characteristic amount of the subject from the image information by the imaging means. Image processing means for detecting the image detection information and outputting the image detection information, and control means for controlling the input and output of the imaging means based on the image detection information by the image processing means and the mode instruction information output from the operation means. At least when the instruction is switched from the monitoring mode to the all-pixel reading mode by the operating means, The signal level of the image information detected by the image processing unit 1
/ N. 2. The image photographing apparatus according to claim 1, wherein the optical characteristic amount of the subject is image information on at least brightness and color. 3. The image photographing apparatus according to claim 1, further comprising an operation unit that gives an instruction to the control unit to capture a moving image of the subject at a certain moment as a still image. 4. When the imaging means and the control means are provided, a memory for recording still image data relating to a still image taken in by the control means is provided, and the control means comprises: 2. The image capturing apparatus according to claim 1, wherein after recording the data, the image capturing unit is controlled to return from the all-pixel reading mode to the monitoring mode.