JP2000184269A - Image pickup device, control method for the image pickup device and recoding medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily obtain image pickup data properly corresponding to a photographing mode by changing an acquisition time of dark image data in response to the photographing mode. SOLUTION: When an image photographing mode is a sports mode or a portrait mode, a flag FDRK is set to '1', and when the image photographing mode is a scenery mode, a close-up mode or a night scenery mode, the flag FDRK is set to '0'. When the flag FDRK is set to '1', after dark reception processing is conducted (S16), photographing processing is conducted (S21), data correction is conducted in development processing of the S24 and then photographing data receiving dark correction are stored in a memory. On the other hand, when the flag FDRK is set to '0', photographing processing is conducted (S21) and dark reception processing is executed (S23), and dark correction is conducted in the development processing of the S24 and photographing data receiving dark correction are stored in the memory.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image pickup apparatus, a control method of the image pickup apparatus, and a recording medium, and more particularly, to an image pickup apparatus for picking up, recording, and reproducing a still image or a moving image, and a control method of the image pickup apparatus. , And a recording medium.

[0002]

2. Description of the Related Art Conventionally, an image pickup apparatus such as an electronic camera for recording and reproducing a still image or a moving image picked up by an image pickup element such as a CCD using a memory card having a solid-state memory element as a recording medium is already known. .

[0003] In this type of imaging apparatus, the user selects a shooting mode, so that single shot shooting in which one frame is shot each time the shutter button is pressed, and continuous shooting while the shutter button is kept pressed. Can be switched between continuous shooting and shooting.

[0004] Some of the above-mentioned child imaging devices can perform so-called dark noise correction processing when photographing using the imaging device.

In this dark noise correction processing, the electric charge is accumulated in the same manner as in the actual photographing without exposing the image sensor, and the dark image data read after the electric charge accumulation and the electric charge accumulation are performed with the image sensor exposed. This is to correct the reproduced image of the captured image data based on the captured image data read after the charge accumulation. By performing such dark noise correction processing, dark current noise generated by the image sensor and minute It is possible to avoid a deterioration in image quality such as pixel loss due to a flaw and to capture a desired high-quality image. In particular, the dark current noise increases as the charge storage time and the temperature of the image sensor increase, so that a large image quality improvement effect can be obtained when performing long-time exposure or exposure at a high temperature. The dark noise correction process performs a useful function for the user of the device.

[0006]

However, in the above-mentioned conventional imaging apparatus, in the case of performing actual photographing after photographing dark image data, when performing continuous photographing, the frame interval of photographed frames may be made uniform. However, when taking a single shot, there is a problem in that the time delay of the shutter release is increased by the shooting time required for shooting the dark image data, so that a valuable shutter chance may be missed.

On the other hand, when the dark image data is photographed after the actual photographing, the time delay of the shutter release can be reduced when performing the single photographing, but the first frame and the second frame are performed when performing the continuous photographing. The shooting interval of the frame increases by the shooting time required for the dark image data,
There is a problem that the interval between the photographed frames cannot be made uniform.

That is, in the conventional imaging apparatus, when performing dark noise correction, it is necessary for the user to determine whether to acquire the dark image data before the actual photographing or after the actual photographing according to the photographing mode. In addition, as a result of imposing a burden on user operations, there is a problem that usability is not always good.

Moreover, in recent image pickup apparatuses, in addition to the control of the optical system, the number of control mechanisms such as arithmetic processing relating to noise elimination is increasing. There is a tendency that the shooting conditions set by operating are increased, and thus complicated operations are more and more increased.
There is a problem that the usability is not always good for the user.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and it is possible to easily obtain captured image data appropriately corresponding to a shooting mode by changing the acquisition time of dark image data according to the shooting mode. It is an object of the present invention to provide an imaging device, a control method of the imaging device, and a recording medium that can perform the imaging.

[0011]

An image pickup apparatus according to the present invention comprises an image pickup device for storing an optical image as electric charge, and a picked-up image obtaining means for obtaining picked-up image data from an image pickup lens by exposing the image pickup device to an exposure state. A dark image acquisition unit that acquires dark image data by setting the imaging device in a non-exposure state; and darkens the captured image data based on an acquisition result of the dark image acquisition unit and an acquisition result of the captured image acquisition unit. A first image capturing mode group for acquiring dark image data by the dark image acquiring unit before acquiring the captured image data by the acquired image acquiring unit; A second photographing mode group for acquiring the dark image data by the dark image acquiring means after acquiring the captured image data by the acquiring means; Selecting means for selecting one photographing mode group from a plurality of photographing mode groups including the first and second photographing mode groups, wherein the dark correcting means includes a photographing mode group selected by the selecting means. Therefore, the present invention is characterized in that the dark image data and the captured image data are sequentially obtained, and dark correction is performed.

A control method of an image pickup apparatus according to the present invention comprises an image pickup device for storing an optical image as electric charge, and an image pickup step of obtaining image pickup image data from an image pickup lens by exposing the image pickup device to an exposure state. A dark image obtaining step of obtaining dark image data by setting the image sensor in a non-exposure state; and performing dark correction on the captured image data based on the obtained result of the dark image obtaining step and the obtained result of the captured image obtaining step. A method of controlling the imaging apparatus including a dark correction step, wherein, before acquiring the captured image data in the captured image acquisition step, selecting a first imaging mode group for acquiring dark image data in the dark image acquisition step, After the captured image data is acquired in the captured image acquisition step, the dark image data is acquired in the dark image acquisition step. It is determined whether or not to select a second shooting mode group to obtain the dark image data and the shot image data according to the shooting mode group according to the selection result, and perform dark correction. And

[0013] A recording medium according to the present invention is a computer-readable recording medium, comprising: an image pickup device for exposing an image pickup device to obtain image pickup image data from an image pickup lens; A dark image acquisition procedure for acquiring dark image data in a state, and executing the dark image acquisition procedure before executing the captured image acquisition procedure, or executing the dark image acquisition procedure after executing the captured image acquisition procedure The dark image data and the captured image data are sequentially acquired in accordance with the selection result selected by the selection procedure, and dark correction is performed based on the dark image data and the captured image data. It is characterized in that a program for executing the correction procedure is recorded.

The other features of the present invention will become apparent from the following description of the embodiments of the present invention.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an image pickup apparatus according to the present invention. The image pickup apparatus includes a detachable interchangeable lens type lens unit 1 and an image pickup unit from the lens unit 1. An image processing unit 2 to which image data is input; a primary battery such as an alkaline battery or a lithium battery for supplying power to the image processing unit 2; a NiCd battery or NiM
A first power supply unit 3 composed of a secondary battery such as an H battery and a first and second memory cards and hard disks connected to the image processing unit 2 via interface (I / F) units 4 and 5; Recording units 6 and 7. The lens unit 1 and the image processing unit 2 are mechanically connected to each other via respective lens mounts 8 and 9, and are electrically connected to each other via connectors 10 and 11. The lens mount 9 or the connector 11 on the image processing unit 2 side incorporates a lens attachment / detachment detection sensor (not shown) for detecting whether or not the lens unit 1 is attached.
Further, the power supply unit 3 and the image processing unit 2 are connected to the connectors 12, 1
The I / F units 4 and 5 and the image processing unit 2 which are electrically connected to each other via the third unit 3 and are connected to the first and second recording units 6 and 7
Are electrically connected to each other via connectors 13 to 16. In the present embodiment, the power supply unit 3 is configured by a battery, but may be configured by another power supply unit such as an AC adapter.

The lens unit 1 includes, specifically, an imaging lens 17 into which an optical image from a subject enters, and an aperture 1.
8 and an aperture 1 in cooperation with a shutter control unit described later based on photometric information from a photometric unit of the image processing unit 2 described later.
Control unit 20 for controlling the focusing lens 8, a distance measurement control unit 20 for controlling the focus of the imaging lens 17, a zoom control unit 21 for controlling the zooming of the imaging lens 17, and the lens unit 1.
It has a lens system control circuit 22 that controls the entire system, and an I / F unit 23 that controls the interface operation with the image processing unit 2. The lens system control circuit 22 stores a memory for storing constants, variables, programs, and the like for operation, identification information unique to the lens unit 1, management information, function information such as an open aperture value, a minimum aperture value, and a focal length.
It has a non-volatile memory for storing current and past set values. The connector 10 transmits a control signal, a state signal, a data signal, and the like between the image processing unit 2 and the lens unit 1 and can supply various currents in both directions. The connector 10 may be configured to enable not only electric communication but also optical communication, voice communication, and the like.

The image processing unit 2 includes a lens unit 1
An image processing block 24 for processing an optical signal from the device as image data, and a system control block 25 for controlling the system of the present apparatus.

The image processing block 24 specifically includes first and second mirrors 26 and 27 and an optical image supplied via the first and second mirrors 26 and 27 by a single-lens reflex method. An optical viewfinder 28 for forming and displaying an image, a shutter 29 for controlling the amount of exposure, and a CCD (imaging device) for accumulating charges from the optical image and converting the optical image into an electric signal
30, an A / D converter 31 for converting an analog electric signal output from the CCD 30 into a digital electric signal, and a memory control circuit 32 for controlling the entire image processing block 24
An image display memory 33 in which image display data is written via the memory control circuit 32; a main memory 34 in which photographed still images and moving images are stored; and a main memory 34 by adaptive discrete cosine transform (ADCT). A compression / expansion circuit 35 for performing compression / expansion processing on the image data stored in the memory 34, and the A / D converter 31 or the memory control circuit 3
An image processing circuit 36 for performing predetermined pixel interpolation processing, color conversion processing, and other predetermined arithmetic processing on the image data from 2;
D / A converter 37 for converting an output signal (digital electric signal) from memory control circuit 32 into an analog electric signal
And the CCD 30, the A / D under the control of the memory control circuit 32.
A timing generating circuit 38 for supplying a clock signal and a control signal to the converter 31 and the D / A converter 37; and a TFT for displaying image display data written in the image display memory 33.
An electronic finder function can be realized by providing an image display unit 39 composed of an LCD or the like and sequentially displaying captured image data on the image display unit 39. The image display unit 39 can be arbitrarily turned on and off according to an instruction from a system control circuit described later. When the display is turned off, the power consumption of the image processing unit 2 is greatly reduced. be able to.

The main memory 34 has a sufficient storage capacity for storing a predetermined number of still images and a moving image for a predetermined period of time, thereby continuously capturing a plurality of still images. Even in the case of continuous shooting or panoramic shooting, it is possible to write a large amount of images at high speed.
The main memory 34 can also be used as a work area of a system control circuit described later.

The above-mentioned optical finder 28 has a predetermined display function. For example, the in-focus display, photographing preparation completion, camera shake warning, flash charging, flash charging completion, shutter speed aperture value, exposure correction, Various information such as a recording medium writing operation is displayed.

In the system control block 25, a number of components are connected to a system control circuit 40 which controls the entire system of the image processing unit 2.

The distance measuring section 41 is provided between the lens unit 1 and the first
Measurement of the focus state of the image data input through the mirror 26 and the distance measuring sub-mirror (not shown), that is, AF
(Auto focus) processing is performed.

The photometric section 42 is provided between the lens unit 1 and the first
AE (automatic exposure) processing, that is, AE (flash light control) by cooperating with a flash, which will be described later, while performing an exposure state measurement of image data that is input through a mirror 26 and a photometric lens (not shown). ) It also has a processing function.

The shutter control section 43 controls the shutter 29 based on the photometric information from the photometric section 44 in cooperation with the aperture control section 19 for controlling the aperture 18.

The flash 44 has an AF auxiliary light projecting function and a flash dimming function.

That is, the system control circuit 40 determines the distance measurement unit 41 based on the calculation result obtained by the image processing circuit 36.
An AF process, an AE process, an EE process, and an AWB (auto white balance) process are performed on the photometric unit 42, the shutter control unit 43, the flash 44, and the like by a TTL (through-the-lens) method.

A power switch 45 is used to switch and set each mode when the image processing section 2 is turned on and off.
The power supply ON / OFF setting of various attached devices such as the lens unit 1 connected to the image processing unit 2, the external strobe, and the first and second recording units 6 and 7 is switched.

The power control unit 46 includes a battery detection circuit, a DC-
It comprises a DC converter and a changeover switch circuit for switching a portion to be energized, and detects whether or not a battery as the power supply unit 3 is installed, the type of battery, and the remaining battery level. DC based on instructions
-Control the DC converter to provide the required voltage for the required period,
The information is supplied to each unit including the first and second recording units 6 and 7.

The system memory 47 stores operation constants, variables, programs, and the like for the system control circuit 40.

The display unit 48 includes a liquid crystal display (LCD), a light emitting diode (LED), a lamp, a speaker, etc., and operates according to the execution of a program by the system control circuit 40 using characters, images, sounds, and the like. And messages are displayed. In addition, at least one display unit 48 is provided at a position easily visible near an operation unit described later.

The LCD of the display unit 48 includes, for example,
Single shot / continuous shooting, self-timer, compression ratio, number of recorded pixels, number of recorded images, number of remaining shots, shutter speed, aperture value, exposure compensation, flash display, red-eye reduction display, macro shooting display, buzzer setting, clock Remaining battery level, remaining battery level, error message, information of a plurality of digits, mounting state of first and second recording units 6 and 7, mounting state of lens unit 1, operation of communication circuit described later, date and time Time display, connection status with an external computer, and the like are displayed.

In the display unit 48, for example, an LED is displayed on the LED, for example, an in-focus display, a photographing preparation completion display,
As in the case of 8, a camera shake warning, flash charging, flash charging completed, recording medium writing operation, macro shooting setting notification, secondary battery charging state display, and the like are displayed.

Further, among the display contents of the display unit 48, for example, a self-timer notification lamp or the like is displayed on the lamp. This self-timer notification lamp may be shared with the AF auxiliary light.

The nonvolatile memory 49 is an electrically erasable / recordable memory, and is composed of, for example, an EEPROM.

The communication circuit 50 is an RS232C, IEEE
It has various communication functions such as 1394, P1284, SCSI, modem, LAN, and wireless communication.

The connector 51 connects the image processing unit 2 to another external device via the communication circuit 50. When the communication circuit 50 has a wireless communication function, an antenna is connected to the communication circuit 50 instead of the connector 51.

The recording section attachment / detachment detection sensor 52 includes a connector 1
It is detected whether or not the connectors 3 and 15 are attached to the connectors 14 and 16.

The system control circuit 40 includes a mode dial 53, first and second shutter switches 5
Operation groups such as 4, 55, a reproduction switch 56 and an operation unit 57 are connected, and instruct the system control circuit 40 to perform various operations.

The mode dial 53 has a control mode switch and an image shooting mode switch. here,
The control mode switch includes an automatic shooting mode, a program shooting mode, a shutter speed priority shooting mode, an aperture priority shooting mode, a manual shooting mode, a depth of focus priority (depth) shooting mode, and a panorama shooting mode. There are a portrait shooting mode, a landscape shooting mode, a close-up shooting mode, a sports shooting mode, and a night scene shooting mode, and these modes can be switched.

FIG. 2 shows a photographing condition management table set by the mode dial 53. The photographing condition management table is stored in the internal memory of the system control circuit 40 or the system memory 47.

The portrait mode is a mode for photographing the upper body of a person and the like. In the present embodiment, the continuous photographing is set so that portraits of a plurality of frames can be continuously photographed. In this case, the AF stops the distance measurement and the control of the optical system once the focus is achieved. In addition, since the AE needs to be adjusted mainly for the person and controlled so that the face of the person does not become dark even in backlight, open the aperture as much as possible to focus on the person who is the main subject and blur the background. Adjust the shutter speed etc.

Normally, landscape photography is set to single photography because continuous photography is not required, and AF stops the control of the distance measuring unit 41 and the aperture control unit 19 once it is focused.
Regarding the AE, taking into consideration the point that “sky” exists above the captured image, the shutter speed and the like are adjusted with the aperture opened so that the captured image is in focus from near to far.

Normally, close-up photographing is also set to single photographing because continuous photographing is not necessary, and AF is used to focus on a narrower range by opening the aperture to the open side. The control in the section 41 and the aperture control section 19 is stopped, and A
E is also automatically adjusted by the photometry unit 44 so as to be optimal for close-up photography.

In the case of sports photography, continuous photography is set in consideration of the movement of the subject. For AF, since the processing must always be performed while the shutter button is pressed, the distance measurement unit 41 and the aperture control unit 19 perform the processing. Perform as needed.

The night view mode is normally set to single-shot shooting because continuous shooting is not required, and the AF stops the control of the distance measuring unit 41 and the aperture control unit 19 once in focus. The AE is controlled by the flash 44 and the photometry unit 42 so that appropriate captured image data can be obtained without emitting a strobe and without darkening the background.

The dark correction flag FDRK is a flag for instructing whether to perform the dark correction processing before the main shooting or after the main shooting, and is linked to the continuous shooting and the single shooting. That is, since it is not necessary to consider the shutter release timing during continuous shooting as in single shooting, the dark noise correction is performed before the main shooting by setting the dark correction flag FDRK to “1”. That is, the noise component of the dark current in the CCD 30 is accumulated before the actual photographing for the same time as the actual photographing, the noise image signal is read out after the accumulation to perform dark noise correction, and the photographing frame interval is made uniform. On the other hand, during single-shot shooting, if dark noise correction is performed before the main shooting, the shutter release timing may be delayed and a valuable photo opportunity may be missed, so the dark correction flag FDRK is set to “0” and darkness is set after the main shooting. Perform noise correction.

In the portrait mode, since the photographing timing does not substantially matter, a single photographing setting may be used instead of the continuous photographing setting.

Returning to FIG. 1, the first shutter switch (SW1) 54 is turned on when a shutter button (not shown) is in a so-called half-pressed state.
It instructs the start of operations such as WB processing and EF processing.

Second shutter switch (SW2) 55
Turns on when the operation of a shutter button (not shown) is completed, and stores image data from the CCD 30 in the main memory 3.
4, writing processing for developing based on the calculation in the image processing circuit 36 and the memory control circuit 32, reading processing for reading image data from the main memory 34, compression of image data in the compression / decompression circuit 35 It instructs the start of a series of processing operations, such as processing, recording processing for writing image data in the first or second recording unit 6,7, and the like.

The reproduction switch 56 is used to store the captured image in the main memory 34 or the first and second
Of the reproduction operation to be read from the recording units 6 and 7 and displayed on the image display unit 39.

The operation unit 57 includes various buttons and a touch panel, and includes a menu button, a set button, a macro button,
Multi-screen playback page break button, flash setting button, single / continuous / self-timer switching button, menu move plus (+) button, menu move minus (-)
Button, playback image move plus (+) button, playback image minus (-) button, shooting image quality selection button, exposure compensation button, date / time setting button, selection and switching setting of various functions at the time of shooting and playback execution such as panorama mode Selection / switching button, a decision / execution button for setting and executing various functions at the time of shooting and playback of a panorama mode, an image display switch for turning on / off the image display unit 39, an image shot immediately after shooting Quick review switch to set the quick review function to automatically play data, select the compression rate of JPEG compression, or CCD
A compression mode switch for selecting a CCD RAW mode for directly digitizing the signal of No. 30 and recording it on a recording medium;
A mode setting switch for setting each function mode such as a playback mode, a multi-screen playback / erase mode, and a PC connection mode;
When the first shutter switch (SW1) 54 is depressed, the AF operation is started, and once in focus, the one-shot AF mode in which the in-focus state is maintained and the first shutter switch (SW1) 54 is depressed. During this operation, the camera has an AF mode setting switch for switching and setting the servo AF mode in which the AF operation is continuously performed.

The functions of the plus button and the minus button can be selected more easily by providing a rotary dial switch.

The I / F unit 58 controls an interface operation with the lens unit 1.

The image processing unit 2 includes an I / F unit 5
9 and 60 are built in, and the I / F units 59 and 60 are
The first and second recording units 6, via connectors 13 to 16,
7 is connected to the I / F units 4 and 5 connected to the control unit 7 and controls the interface operation with the recording unit.

Next, a control method of the image pickup apparatus according to the present invention will be described.

FIGS. 3 and 4 are flowcharts showing a control procedure of the control method of the image pickup apparatus according to the present invention. This program is executed by the system control circuit 40.

In FIG. 3, first, in step S1, the dark correction flag FDRK, control variables, and the like are initialized, and predetermined initialization is performed.

Next, at step S2, the power switch 4
5 is turned on or not, and the answer is negative (N
In the case of o), a predetermined end process is executed, and the process returns to step S2. That is, the display of each display unit is changed to the end state,
The necessary parameters including the dark correction flag FDRK, control variables, and the like, setting values, and setting modes are written in the non-volatile memory 49.
Then, end processing such as shutting off unnecessary power in each component of the image processing unit 2 including the above is performed, and the process returns to step S2.

On the other hand, if it is determined in step S2 that the power switch 45 is turned on, the process proceeds to step S4, where the power control unit 46 determines whether the remaining capacity of the battery constituting the power supply unit 3 is sufficient. If it is determined that the answer is negative (No), a predetermined warning display using an image or a sound is performed on the display unit 48 (step S5), and the process returns to step S2.

The answer to step S4 is affirmative (Yes).
In the case of, it is determined whether or not the mode dial 53 is set to the image shooting mode. When the answer is negative (No), that is, in the automatic shooting mode or the program shooting mode,
Alternatively, when a control mode such as a shutter speed priority shooting mode is set, the process proceeds to step S7, where a predetermined process corresponding to the set control mode is executed, and step S7 is performed.
Return to 2.

On the other hand, if the answer to step S6 is affirmative (Yes), it is determined whether or not the first and / or second recording units 6, 7 are attached to the image processing unit 2, and the first or the second recording unit 6, 7 is determined. / And when the second recording units 6 and 7 are attached to the image processing unit 2, the management information of the image data recorded in the first and second recording units 6 and 7 is acquired and the The operation state is the operation of the image processing unit 2, particularly the first and / or second recording units 6, 7.
It is determined whether there is a problem in the recording / reproducing operation of the image data with respect to. If the answer is negative (No), the process proceeds to step S5, where a predetermined warning is displayed on the display unit 47 by image or sound, and then the process returns to step S2.

On the other hand, the answer to step S8 is affirmative (Yes).
In the case of, the process proceeds to step S9, and it is determined whether or not the sports mode or the portrait mode is selected by setting the mode dial 53. If the answer is affirmative (Yes), the process proceeds to step S10, in which the dark correction flag FDRK is set to "1" to instruct that the dark image is to be photographed before the actual photographing, and the answer in step S9 is negative. (No), that is, if the landscape mode, the close-up mode, or the night scene mode has been set, the process proceeds to step S11, in which the dark correction flag FDRK is set to “0” and the dark image is shot after the actual shooting. Then, the process proceeds to step S12. That is, when the continuous shooting mode is set, such as the sports mode or the portrait mode, the dark correction flag FDRK is set to “1”, and the dark image is shot before the actual shooting, and the noise is set together with the shooting data. While the image signal is read and dark noise correction is performed, the dark correction flag FDRK is set to “0” when a single shooting mode is set, such as a landscape mode, a close-up mode, or a night scene mode, and a dark image is set. The photographing is performed after the actual photographing to avoid delaying the shutter release timing.

Next, in step S12, the display of various setting states of the image processing section 2 is displayed on the display section 48 using images and sounds.
And proceeds to step S13 in FIG. When the image display unit 39 is set to be able to display an image, the image display unit 39 also displays various setting states of the image processing unit 2 using images and sounds.

In step S13, it is determined whether or not the first shutter switch (SW1) 54 has been pressed.
When the answer is negative (No), the process returns to step S2 in FIG. 3, while when the answer is affirmative (Yes), the distance measurement / photometry process is executed (step S14) and the process proceeds to step S15. That is, the focus of the taking lens 17 is adjusted to the subject by performing the distance measurement process, the aperture value and the shutter time are determined by performing the photometry process, and the flash setting is performed as necessary.

Next, in step S15, it is determined whether or not the dark correction flag FDRK is "1". When the dark correction flag FDRK is "0", that is, when dark correction is performed after the main photographing, the process proceeds to step S17. When the dark correction flag FDRK is “1”, that is, when dark correction is performed before the main photographing, dark capture processing is executed in step S16, and the process proceeds to step S17. That is, with the shutter 29 in the open state, noise components such as dark current of the CCD 30 are accumulated for the same time as the actual photographing, the accumulated noise image signal is read, and the process proceeds to step S17.

Then, in a step S17, it is determined whether or not the second shutter switch (SW2) 55 is depressed. If the answer is negative (No), the process proceeds to a step S18, where the first shutter switch (SW1) is switched. It is determined whether or not the button 54 has been pressed. If the answer is affirmative (Yes), the process returns to step S17. On the other hand, if the first shutter switch (SW1) 54 is no longer pressed, it is determined that shooting has ended. Then, the process returns to step S2 in FIG.

On the other hand, if it is determined in step S17 that the second shutter switch (SW2) 55 has been pressed, the flow advances to step S19. The dark correction flag FDRK
Is set to "1" and the dark noise correction is performed before the actual photographing by the dark capture processing, the second shutter switch (SW2) 55 is pressed to make the continuous photographing frame intervals substantially uniform. be able to.

In step S19, it is determined whether or not a storage area capable of storing data exists in the main memory 34. If the answer is negative (No), a predetermined warning is displayed on the display unit 48 by an image or sound. Display is performed (step S2
0), and then return to step S2 in FIG. For example, immediately after the maximum number of continuous shots that can be stored in the image storage buffer area of the main memory 34 has been performed, recording and writing from the main memory 34 to the first or second recording unit 6 or 7 is not possible. If this has not been done yet, and an empty area has not been secured in the main memory 34, the answer to step S19 is negative (No).

When the captured image data is compressed and then stored in the main memory 34, the storable area is determined in consideration of the fact that the amount of compressed image data varies depending on the setting of the compression mode. It is determined in step S19 whether or not the image is in the image storage buffer area of the main memory 34.

Then, the answer to step S19 is affirmative (Ye).
In the case of s), a photographing process is executed in step S21, and the process proceeds to step S22. That is, an image pickup signal obtained by image pickup and charge accumulation for a predetermined time is read out from the CCD 30, and is read via the A / D converter 31, the image processing circuit 36, the memory control circuit 32, or directly from the A / D converter 31. 32, the captured image data is stored in the main memory 34.
And the process proceeds to step S22.

Next, in step S22, it is determined whether or not the dark correction flag FDRK is "1". If the answer is affirmative (Yes), the process proceeds to step S24. If the answer is negative (No), the process proceeds to step S24. After executing the dark capture process similar to S16 (step S23), the process proceeds to step S23.
Proceed to 24. That is, if the dark correction flag FDRK is set to “1” in step S22, the dark capture processing is not performed because the dark capture processing has already been performed prior to the execution of the continuous shooting in step S16. On the other hand, when the dark correction flag is set to “0”, the dark noise correction has not been performed yet, so that the dark capture process is executed in step S23, and then the process proceeds to step S24.

Next, in step S24, the photographed image data written in a predetermined area of the main memory 34 is read out, and the AWB is performed using the operation result stored in the internal memory of the system control circuit 40 or the system memory 47.
Various development processes including a process, a gamma conversion process, and a color conversion process are performed. Further, in the developing process, step S1
6 or a subtraction process is performed using the dark image data acquired in the dark acquisition process in step S23.
The dark correction arithmetic processing for canceling the dark current noise or the like is performed.

Next, in step S25, the main memory 3
The image data written in 4 is read, image compression processing according to the set mode is performed by the compression / expansion circuit 35, and the image data after the series of processing is written in a predetermined area of the main memory 34.

Next, in step S26, a recording operation is started. That is, the image data stored in the main memory 34 is read, and the I / F units 59 and 60 and the connector 1 are read.
The writing process of the recording image data to the first or second recording unit 6 or 7 via the recording unit 4 or 16 is started. The recording start processing is
The writing of the image data which has been subjected to the above-described series of processes after the photographing is performed on the recording image data every time the image data is newly written in a predetermined area of the main memory 34. In addition, while the image data is being written to the first or second recording unit 6 or 7, the display unit 48 displays the first or second image such as blinking an LED to clearly indicate that the writing operation is being performed. Second
Is displayed on the recording units 6 and 7.

Then, in a succeeding step S27, it is determined whether or not the first shutter switch (SW1) 54 is depressed. When the answer is negative (No), the process returns to the step S2 in FIG. Is affirmative (Yes), it is determined in step S28 whether or not the dark correction flag FDRK is "1". If the answer is negative (No), that is, if the single shooting mode is set, the process returns to step S27. The current state is maintained until the first shutter switch (SW1) 54 is released, and the process returns to step S2 when the first shutter switch (SW1) 54 is released.

On the other hand, the result of step S28 is affirmative (Ye
s), that is, when the continuous shooting mode is set, the process returns to step S17, and the above processing is repeated.

FIG. 5 is a flowchart of a distance measurement / photometry processing routine executed in step S14 of FIG.

In the distance measurement / photometry processing, transmission and reception of various signals between the system control circuit 40 and the aperture control unit 19 or the distance measurement control unit 21 are performed by the I / F unit 58, the connector 11, the connector 10, / F section 23 and the lens system control circuit 22.

First, in step S31, the distance measuring means 41
Then, the AF process is started using the distance measurement control unit 21, then, in step S 32, the in-focus state of the image formed as the optical image is determined, and the distance measurement control unit 20 controls the imaging lens 17.
Is driven, and the focusing state is detected by the distance measuring means 41.
Then, in a succeeding step S33, it is determined whether or not the distance measurement is appropriate. If the answer is negative (No), the process returns to the step S32 to continue the distance measurement control, while the answer is affirmative (Yes).
In step S34, the process proceeds to step S34, in which a focused ranging point is determined from a plurality of ranging points in the shooting screen, and the ranging data together with the determined ranging point data is stored in the internal memory of the system control circuit 40 or the system. Stored in the memory 47 and step S3
Go to 5.

In step S35, the AE process is started using the photometric means 42. That is, the optical image incident on the imaging lens 17 is supplied to the photometric unit 44, and the exposure state of the image formed as the optical image is measured. Next, step S3
In step 7, it is determined whether the exposure state is appropriate. If the answer is negative (No), the process returns to step S37 to continue the photometric control, while if the answer is affirmative (Yes), the photometric data is controlled by the system control. After storing in the internal memory of the circuit 40 or the system memory 47, the process proceeds to step S38. The aperture value and the shutter speed are determined according to the exposure result detected in the photometric processing and the control mode set by the mode dial 53, and the charge accumulation time of the CCD 30 is determined according to the shutter speed. Based on the processing, a photographing process and a dark capture process are performed.

Next, in step S38, it is determined whether or not the flash 44 is necessary based on the measurement data obtained in the photometric processing. If the answer is negative (No), the process returns to the main routine (FIG. 4). On the other hand, when the answer is affirmative (Yes), the charging process of the flash 44 is performed, and step S
After the charging of the flash 44 is completed at 40, the process returns to the main routine (FIG. 4).

FIG. 6 is a flowchart of the photographing processing routine executed in step S21 of FIG.

In the photographing process, the system control circuit 40
The transmission and reception of various signals between the iris control unit 19 and the distance measurement control unit 21 are performed by the I / F unit 58, the connector 11, the connector 1
2, which is performed via the I / F unit 23 and the system lens control circuit 22.

In step S41, the first mirror 26 is moved to a predetermined mirror-up position by a mirror driving means (not shown).
The aperture control unit 19 is driven based on the photometric data stored in the internal memory
8 is moved to a predetermined aperture position.

Next, after clearing the charge stored in the CCD 30 (step S43), charge storage in the CCD 30 is started (step S44).
To open the shutter 29 (step S
45), exposure of the CCD 30 is started (step S4).
6).

Next, in step S47, the flash 44
Is necessary or not, and the answer is negative (N
In the case of o), the process proceeds to step S49, and when the answer is affirmative (Ye), the flash 44 is caused to emit light (step S48), and thereafter, the process proceeds to step S49.

Next, in step S50, it is determined whether or not the exposure has been completed. If it is determined that the exposure of the CCD 30 has been completed in accordance with the photometric data, the shutter control unit 43
As a result, the shutter 29 is closed, and the exposure of the CCD 30 is completed (step S50). Then, in a succeeding step S51, the diaphragm 18 is moved to an open diaphragm position via the diaphragm control unit 19, and then in a step S52, the first mirror 26 is moved to a mirror down position by a mirror driving unit (not shown).

Next, in step S53, it is determined whether or not the set charge accumulation time has elapsed (step S53).
When the set charge accumulation time has elapsed, the charge accumulation of the CCD 30 is terminated (step S54).
Read out the charge-stored image signal from the A / D
The captured image data is written to the main memory 34 via the converter 31, the image processing circuit 36, the memory control circuit 32, or directly from the A / D converter 31 via the memory control circuit 32 (step S55), and the main routine (FIG. Return to 4).

FIG. 7 is a flowchart of the dark capture processing routine executed in step S16 or S23 in FIG.

After the charge stored in the CCD 30 has been cleared in step S61, the shutter 29 is closed and the CCD 3
The charge accumulation of 0 is started (step S62). And
It is determined whether or not the set predetermined charge storage time has elapsed (step S63). When the predetermined charge storage time has elapsed, the charge storage of the CCD 30 is terminated (step S64). Read, A
/ D converter 31, image processing circuit 36, memory control circuit 3
2 or the A / D converter 31 directly writes dark image data to the main memory 34 via the memory control circuit 32 (step S65), and returns to the main routine (FIG. 4).

Then, by performing development processing using the dark noise correction data, a photographed image is obtained with respect to image quality deterioration such as dark current noise generated by the CCD 30 and pixel defects caused by minute scratches generated in the CCD 30. Data can be corrected.

FIG. 8 is a time chart showing the relationship between the state of the CCD 30 and the first and second shutter switches 54 and 55. FIG. 8A shows continuous shooting such as sports shooting (FDRK = 1). FIG. 8B shows the case of single shooting (FDRK = 0) such as landscape shooting.

That is, in the case of continuous shooting, FIG.
, The first shutter switch (SW1) 5
When the button 4 is pressed, the photographing conditions such as the distance measurement and the photometry are set, the shutter 29 is closed, the dark capture process is performed, and the exposure / readout process for dark correction is performed. Second shutter switch (SW2) 55
When is pressed, the photographing process starts. That is, the exposure is started with the shutter 29 in the open state, and when the exposure is completed, the shutter 29 is closed and the image signal is read from the CCD 30. Thereafter, the first and second shutter switches 54 and 55 are used during continuous shooting. Maintains the ON state and CC
D30 repeats the exposure process and the read process. Then, by releasing the first and second shutter switches 54 and 55, one continuous shooting is completed.

On the other hand, in the case of single shooting, as in the case of continuous shooting, when the first shutter switch (SW1) 54 is depressed, as shown in FIG. Are set. And the shutter 29
When the shutter is closed, the charge of the CCD 30 is cleared, and then, when the second shutter switch (SW2) 55 is pressed, the photographing process starts. That is, exposure is started with the shutter 29 opened, and when the exposure is completed, the shutter 2 is opened.
9 is closed, and the image signal is read from the CCD 30. And
Thereafter, a dark capture process is performed, an exposure / readout process for dark correction is performed, and the first and second shutter switches 54 and 55 are released to terminate the process.

FIG. 9 is a time chart showing the flow of captured image data captured by the image capturing apparatus over time.
FIG. 9A shows the case of continuous shooting, and FIG. 9B shows the case of single shooting.

In the case of continuous shooting, as shown in FIG. 9 (a), shooting conditions for distance measurement, photometry, control of other optical systems, etc. are set during time t1, and this time t1 is set.
1, the dark image data is temporarily stored in the main memory 34, the main image is taken by the imaging lens 17 at time t2, and the dark image data is stored in the main memory 34 at time t1 after the main shooting. Is subtracted from the main photographing data, and the result of the subtraction is stored in the main memory 34 at time t3. Thereafter, similarly, time t3 and time t
4, the dark image data photographed at time t1 is subtracted from the main photographing data continuously photographed at times t3 and t4, and the subtraction result is stored in the main memory 34 at times t4 and t5, respectively. To be stored.

On the other hand, in the case of single shooting, as shown in FIG. 9B, the shooting conditions are set at time t1, and then the actual shooting is performed at time t2, as in the case of continuous shooting. The captured image data is temporarily stored in the main memory 34. Next, a dark image is photographed at time t3, the dark image data is subtracted from the actual photographing data, and the subtraction result is stored in the main memory 34 at time t4.

Then, by reading out the subtracted image data stored in the main memory 34 and displaying it on the image display section 39, the user can obtain a desired reproduced image with dark noise correction. Can be.

As described above, in the present embodiment, by appropriately changing the photographing sequence according to the image photographing mode, in the case of single photographing, the photographed image data on which the desired dark noise correction has been performed without missing a photo opportunity. Can be easily obtained, and in the case of continuous shooting, it is possible to easily obtain picked-up image data in which dark noise correction is performed at a plurality of frame intervals, thereby obtaining picked-up image data appropriately corresponding to the shooting scene. Can be easily obtained, and the usability of the user is improved.

The present invention is not limited to the above embodiment. In the above-described embodiment, the charge accumulation time of the photographing process and the charge accumulation time of the dark capture process are the same. However, if the charge accumulation time is within a range enough to correct dark current noise and the like, different charge accumulation times are used. May be.

During the dark capture process (step S16 or step S23), the photographing operation cannot be performed.
The image or sound indicating that the image processing unit 2 is busy may be displayed by the image display unit 7 or the image display unit 39.

Further, in the above embodiment, the photographing operation is performed by moving the first mirror 26 to the mirror-up position and the mirror-down position, but the photographing operation is performed without moving the first mirror 26 as a half mirror. The operation may be performed.

The recording media mounted on the first and second recording units 6 and 7 are not limited to memory cards such as PC cards and compact flashes, hard disks, and the like.
Micro DAT, magneto-optical disk, CD-R and CD-W
Needless to say, the first and second recording units 6 and 7 may be constituted by an optical disk such as an R or a phase change optical disk such as a DVD. Or a part of the composite recording medium may be configured to be detachable.

In the present embodiment, the first and second recording units 6 and 7 are detachably mounted on the image processing unit 2, but at least one of them is integrally fixed to the image processing unit 2. It may be.

Further, in the embodiment of the present invention, the image processing circuit 36 performs predetermined arithmetic processing using the captured image data as necessary, and the system control circuit 40 executes the processing based on the obtained arithmetic result. TTL AF processing for controlling the shutter control unit 43, the distance measurement control unit 42, and the like;
Although AE processing, EF processing, and the like are performed, AF processing, AE processing, and EF processing are performed only by the distance measurement unit 41 and the photometry unit 44, and the image processing circuit 36 performs AF processing, AE processing, and EF processing. It is good also as composition which does not perform each process of.

The measurement result by the distance measuring section 42 and the CCD
30 and the image processing circuit 3
The AF control may be performed based on the calculation result calculated in step 6, and the AE control is performed based on the measurement result obtained by the photometry unit 44, the image data captured by the CCD 30 and the calculation result calculated by the image processing circuit 36. It goes without saying that you can go.

The image data picked up by the CCD 30 is calculated by the image processing circuit 36, and based on the calculation result in the image processing circuit 36, the system control circuit 40 controls the shutter control unit 43, the aperture control unit 19, the distance measurement Control unit 2
0 using the video TTL method that controls the
It is also possible to perform control and AF control.

[0109]

As described above in detail, according to the present invention, a desired dark noise correction can be performed without missing a photo opportunity in single shooting by appropriately changing a shooting sequence according to an image shooting mode. It is possible to easily obtain captured image data, and in the case of continuous shooting, it is possible to easily obtain captured image data that has been subjected to dark noise correction at a plurality of frame intervals, thereby appropriately selecting a shooting scene. You can easily obtain the corresponding captured image data,
User convenience is improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an imaging apparatus according to the present invention.

FIG. 2 is a table diagram of a shooting management table set by a mode dial;

FIG. 3 is a flowchart (1/2) illustrating a control procedure of a control method of the imaging apparatus according to the present invention.

FIG. 4 is a flowchart (2/2) showing a control procedure of a control method of the imaging apparatus according to the present invention.

FIG. 5 is a flowchart of a ranging / photometry processing routine.

FIG. 6 is a flowchart of a shooting processing routine.

FIG. 7 is a flowchart of a dark capture processing routine.

FIG. 8 is a time chart showing a relationship between a state of a CCD and first and second shutter switches.

FIG. 9 is a time chart showing the flow of captured image data captured by the image capturing apparatus over time.

[Explanation of symbols]

17 imaging lens 30 CCD (imaging element) 32 memory control circuit (captured image acquisition means, dark correction means) 36 image processing circuit (captured image acquisition means, dark correction means)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H002 AB01 AB03 CC00 DB02 DB06 DB19 EB00 FB28 FB51 FB84 GA05 GA13 GA19 GA26 GA27 GA28 GA54 HA05 HA11 JA07 2H054 AA01 5C022 AA13 AB02 AB12 AB22 AB37 AB40 AB66 AC03 AC12 AC16 AC54 AC52 AC52 AC56 AC72 AC73 5C024 AA01 BA01 CA09 CA10 DA04 EA02 EA03 EA04 FA01 FA08 GA11 HA14 HA24 HA25 JA04

Claims (22)

[Claims] An imaging device for accumulating an optical image as electric charges; an imaging device for exposing the imaging device to an exposure state to acquire imaging image data from an imaging lens; An imaging apparatus comprising: a dark image acquisition unit that acquires image data; and a dark correction unit that darkens the captured image data based on an acquisition result of the dark image acquisition unit and an acquisition result of the captured image acquisition unit. A first photographing mode group for acquiring dark image data by the dark image acquiring means before acquiring the photographed image data by the photographed image acquiring means, and a dark mode after acquiring the photographed image data by the photographed image acquiring means. A second photographing mode group for acquiring dark image data by the image acquiring means, and a plurality of photographing modes including the first and second photographing mode groups Selecting means for selecting one photographing mode group from the photographing mode group, wherein the dark correction means sequentially performs the dark image data and the photographed image data according to the photographing mode group selected by the selecting means, respectively. An imaging device, which acquires and performs dark correction. 2. A storage unit for storing the captured image data and the dark image data, wherein the dark correction unit converts the captured image data stored in the storage unit into the dark image stored in the storage unit. 2. The imaging device according to claim 1, wherein the imaging device is a subtraction unit that subtracts image data. 3. The first shooting mode group is a continuous shooting mode for continuously shooting a subject, and the second shooting mode group is a single shooting mode for shooting a subject once. The imaging device according to claim 1, wherein: 4. The first shooting mode group includes at least a first shooting operation mode for shooting an irregularly moving main subject and a second shooting operation mode for shooting a person as a main subject. The imaging device according to claim 1, wherein: 5. The imaging apparatus according to claim 4, wherein the first shooting operation mode includes a sports shooting mode. 6. The imaging apparatus according to claim 4, wherein the second photographing operation mode includes a portrait photographing mode. 7. The second photographing mode group includes at least a third photographing operation mode for focusing and photographing a plurality of subjects having different subject depths, and a fourth photographing mode for photographing in close proximity to a main subject. The imaging apparatus according to claim 1, further comprising: a shooting operation mode for shooting a subject having a high degree of darkness. 8. The imaging device according to claim 7, wherein the third shooting operation mode includes a landscape mode. 9. The imaging apparatus according to claim 7, wherein the fourth shooting operation mode includes a close-up mode. 10. The imaging apparatus according to claim 7, wherein the fifth shooting operation mode includes a night scene mode. 11. An image pickup device comprising: an image pickup device for accumulating an optical image as electric charges; and an image pickup step of setting the image pickup device to an exposure state to obtain pickup image data from an image pickup lens; and setting the image pickup device to a non-exposure state. An imaging apparatus comprising: a dark image acquisition step of acquiring dark image data; and a dark correction step of performing dark correction on the captured image data based on an acquisition result of the dark image acquisition step and an acquisition result of the captured image acquisition step. In the control method, before acquiring captured image data in the captured image acquisition step, selecting a first imaging mode group for acquiring dark image data in the dark image acquisition step, or selecting captured image data in the captured image acquisition step Second photographing mode group for acquiring dark image data in the dark image acquiring step after acquiring Control method for an imaging apparatus that determines whether to select the dark image data and the captured image data respectively sequentially obtained in accordance with image pickup mode group corresponding to the selection result, and performs dark correction. 12. The method according to claim 11, wherein the captured image data and the dark image data are stored, and wherein the dark correction step subtracts the stored dark image data from the stored captured image data. A method for controlling an imaging device. 13. The first shooting mode group is a continuous shooting mode for continuously shooting a subject, and the second shooting mode group is a single shooting mode for shooting a subject once. The method for controlling an imaging device according to claim 11, wherein: 14. The first photographing mode group includes at least a first photographing operation mode for photographing a main subject that moves irregularly, and a second photographing operation mode for photographing a person as a main subject. 14. The control method for an imaging device according to claim 11, wherein: 15. The method according to claim 14, wherein the first photographing operation mode includes a sports photographing mode. 16. The apparatus according to claim 14, wherein said second photographing operation mode includes a portrait photographing mode.
The control method of the imaging device according to the above. 17. The second photographing mode group includes at least a third photographing operation mode for focusing and photographing respective subjects having different depths of a subject, and a fourth photographing mode for photographing close to a main subject. 14. The method according to claim 11, further comprising: a photographing operation mode for photographing a subject having a high degree of darkness. 18. The method according to claim 17, wherein the third shooting operation mode includes a landscape mode. 19. The method according to claim 17, wherein the fourth photographing operation mode includes a close-up mode. 20. The method according to claim 17, wherein the fifth shooting operation mode includes a night scene mode. 21. A captured image obtaining procedure for obtaining captured image data from an imaging lens by exposing an image sensor to an exposure state;
A dark image acquisition procedure for acquiring dark image data by leaving the imaging element in a non-exposure state, and executing the dark image acquisition procedure before executing the captured image acquisition procedure, or executing a dark image acquisition after executing the captured image acquisition procedure. A selection procedure for selecting whether to execute the image acquisition procedure, and sequentially acquiring the dark image data and the captured image data according to the selection result selected by the selection procedure, based on the dark image data and the captured image data. A computer-readable recording medium on which a program for executing the dark correction procedure for performing dark correction is recorded. 22. A storage procedure for storing the captured image data and the dark image data in storage means, wherein the dark correction procedure is a subtraction procedure for subtracting the dark image data from the captured image data. 22. The recording medium according to claim 21, wherein: