JPH1042181A - Camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow the camera to flexibly cope with various image pickup operations for digital signal processing. SOLUTION: A copy image is formed to a charge coupled device(CCD) of an image pickup block 2 through an optical block 1 and converted into an image signal. Then the analog image signal from the CCD is converted into a digital signal by an A/D converter 4 and prescribed signal processing is conducted by a digital signal processing section 5. Furthermore, required prescribed information is obtained by preparation of image pickup under the control of an MPU 3 through the processing of the digital signal processing section 5 and main image pickup is conducted according to the information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera for performing digital signal processing.

[0002]

2. Description of the Related Art FIG. 6 is a block diagram showing a configuration of a conventional digital camera. In the figure, reference numeral 51 denotes an optical block such as a lens and a shutter, and reference numeral 52 denotes a CCD which is a solid-state image sensor, which uses a general movie type sensor.

Reference numeral 53 denotes a CPU for controlling each block and the entire system; 54, an A / D converter for converting an image pickup output of the CCD 52 into a digital signal; and 55, an A / D converter.
A digital signal processing unit for digitally processing a video signal input from the converter 54 through the ADC bus 59;
A recording unit 6 digitally records image data input from the CCD 52 through the ADD bus 60 onto a recording medium.

Reference numeral 57 denotes a D / A converter for converting a digital signal from the digital signal processing unit 55 into an analog signal, and 58 denotes an output of the D / A converter 57 to an external TV.
This is a video output unit for outputting to a monitor or the like.

In the camera having the above configuration, the video signal output from the CCD 52 through the optical
The digital signal is converted into a digital signal by the / D converter 54, gamma processing and other signal correction are performed by the digital signal processing unit 55, and the digital data is recorded in the recording unit 56. Further, after the data of the recording unit 56 is converted into an analog signal by a D / A converter 57 through a digital signal processing unit 55, the data is converted into a TV signal by a video output unit 58, and an external T
The video is projected on a V monitor or the like.

[0006]

However, the conventional camera as described above has a problem that it may not be possible to cope with various photographing operations.

[0007] For example, since a low battery is not detected at the time of photographing using a plurality of means, it is not possible to flexibly cope with various photographing operations.

Further, since AF, AE, and AWB (auto white balance) use the same image area of the entire screen, an optimum exposure in AF cannot be obtained. In addition, AE and AWB have some problems in accuracy, and AF / A
The processing was time-consuming because each measurement was performed individually by E.AWB.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a camera which can flexibly cope with various photographing operations.

[0010]

A camera according to the present invention comprises:
It is configured as follows.

(1) Imaging means for converting a photographed subject image into an electric image signal, an A / D converter for converting an analog image signal from the imaging means into a digital signal, and Signal processing means for performing predetermined signal processing; predetermined processing information is obtained by the processing of the signal processing means.

(2) In the camera of the above (1), photometric information for focus adjustment and photometric information for exposure adjustment as predetermined information for photographing are obtained from different areas of the imaging means.

(3) In the camera of (1) or (2), colorimetric information of an image is obtained from a plurality of image areas of the image pickup means as predetermined information for photographing.

(4) In the camera of (3), an image area having valid data is selected from a plurality of colorimetric data.

(5) In the camera of (1), photometric information for exposure adjustment and colorimetric information of an image are simultaneously obtained as predetermined information for photographing.

(6) In any one of the cameras (1) to (5), after obtaining predetermined information for photographing, actual photographing is performed and the digital image signal from the signal processing means is stored in the storage means. I did it.

(7) In the camera of (6), after obtaining predetermined information for photographing, only the actual photographing is repeated.

(8) In the camera of (7), the cancel operation of the user is accepted during the operation of obtaining predetermined information for photographing, and the cancel operation is not accepted during the actual photographing.

(9) In any one of the cameras (1) to (8), if the voltage of the built-in power supply falls below a predetermined value during the operation of obtaining predetermined information for photographing, the operation is interrupted. I did it.

(10) In any one of the cameras (1) to (8), when the voltage of the internal power supply falls below a certain threshold, the processing being executed is interrupted, and the voltage is further lowered. When the voltage drops below the threshold, the power switch is turned off.

[0021]

FIG. 1 is a block diagram showing the system configuration of a camera according to the present invention. Here, the system configuration of a digital camera is shown.

Referring to FIG. 1, reference numeral 1 denotes an optical block having a lens, a shutter, and the like, and reference numeral 2 denotes a CCD (solid-state image sensor) or TG that converts a captured subject image into an electric image signal.
(Timing generator) and CDS (Correlation)
The CCD used here is provided with a light receiving section close to a square pixel in consideration of image processing by a computer.

Reference numeral 3 denotes an MPU (microprocessor unit) which is control means for controlling each block and the entire system. A bus is connected to the MPU 3 and image data is transferred from a memory on the bus to the MPU.
The arithmetic circuit in U3 can perform arithmetic processing on image data.

Reference numeral 4 denotes an A / D converter (converter) for converting an image pickup output of the CCD into a digital signal; 5, a digital signal processing unit for performing predetermined signal processing on a video signal from the A / D converter; This is a memory (storage means) composed of a readable and writable DRAM that temporarily stores image data from the CCD, and writes and reads various data required by this system such as a work area in addition to image data. It is possible to do. Then, the digital signal processing unit 5 transfers the image data to the memory 6 when the camera is in the shooting mode.
Digital signal processor 5 and memory 6 through D bus 12
Various types of image processing such as WB (white balance), AE correction, gamma processing, image compression, and the like are performed while transmitting and receiving data.

Reference numeral 7 denotes a built-in recording unit for recording digital signals on a built-in recording medium, which uses a nonvolatile memory such as a flash memory. Reference numeral 8 denotes a PC card interface for reading and writing a PC card conforming to the PCMCIA, and a hard disk (H) of the PC card Type III.
A recording medium such as DD) or a flash memory card can be connected. Reference numeral 9 denotes an external bus interface (I / F) for transmitting and receiving data to and from an external expansion unit, and is mainly used for connection to a personal computer.

Reference numeral 10 denotes a flash unit for flash photography of the present camera.
Control such as start / stop of light emission and charging of the main capacitor is performed by a control signal from U3. Further, the full charge is detected by reading the voltage level (charging voltage) of the main capacitor of the strobe unit 10 using an A / D converter inside the MPU 3.

Reference numeral 11 denotes an ADC bus (10) for transferring data from the A / D converter 4 to the digital signal processing unit 5.
The ADD bus 12 is a bus (1) for mutually transmitting and receiving data among the MPU 3, the digital signal processing unit 5, the memory 6, the built-in recording unit 7, the PC card interface 8, and the external interface 9.
6-bit bus line).

Reference numeral 13 denotes a release switch of the camera, various other operation changeover switches, and an operation unit related to a user interface for displaying an image by an LCD, an LED, or the like. User interface related operations are performed by exchange.

Reference numeral 14 denotes a battery (built-in power supply). Examples of the battery type include an alkaline manganese AA battery, a nickel cadmium battery, and an AC adapter. The battery level is detected by using an A / D converter inside the MPU 3 to read the voltage level of the battery 14, and detects a low battery or the like. Reference numeral 15 denotes the power supply circuit.

FIG. 2 is a diagram showing an internal circuit configuration of the digital signal processing circuit 5. As shown in FIG. In the figure, 11 is the ADC bus (10-bit bus line) shown in FIG.
Bus (16-bit bus line).

In FIG. 2, reference numeral 20 denotes an ADC bus 11 or an AD bus.
It is an interface between the D bus 12 and an internal signal processing circuit.
It has a data conversion circuit that converts (10/16 conversion) or reverse conversion (16/10 conversion) to 16-bit width data of the DD bus, and changes the data flow under the control of the MPU 3. Can also.

Reference numeral 21 denotes a signal processor which generates and processes the input raw data from the CCD into a video signal of luminance and color difference, and outputs a video signal, a photometric value and a colorimetric value obtained in a process of the process. And various information data such as high-frequency components of video and the like can be obtained as needed.

Reference numeral 22 denotes a compression circuit composed of an IC for JPEG-compressing the video signal from the signal processor unit 21, and 23 denotes a data interface unit 20 and a compression circuit 2
2 is a JPEG bus for exchanging data with the JPEG2.

Next, the photographing operation of the above-configured camera will be described.

When the user takes a picture of a subject, first, when the release switch on the operation unit 13 is pressed, the microcomputer of the operation unit 13 detects that the release switch is pressed,
The power supply circuit 15 is controlled to turn on the digital signal processing unit 5, memory 6, built-in recording unit 7, PC card interface 8, external bus interface 9, and strobe unit 10 shown in FIG. When the power is turned on to the MPU 3, program data is loaded from an internal program ROM, and an initialization process is performed.

In the above-described initialization processing, the above-described units are set in an operation preparation state, and the minimum necessary operations are performed. For example, it communicates with the microcomputer of the operation unit 13 to check the state of the user's operation or to perform a default liquid crystal display. In addition, if a PC card is inserted, for example, the remaining amount of the PC card is obtained or a necessary directory is created. If an abnormality is detected in the PC card, the abnormality is displayed on the LCD as an error.

As a result of communication with the microcomputer of the operation unit 13, when it is detected that the release switch has been pressed, a photographing sequence process is executed. FIG. 3 shows a diagram of a main flow of this photographing sequence. The release switch is a switch for starting a photographing operation of the camera, and has a double switch structure of SW1 and SW2 having different strokes.

In the flow of FIG. 3, when the switch SW1 is first pressed, a load test in step 100 is performed, and then a safety low battery (Safety LB) check is performed. At the same time, step 10
The SafetyLB check of one fixed cycle is performed.
If LB is detected in either the Safety LB check in step 100 or step 101, the photographing sequence is immediately terminated, and the LB display is displayed on the liquid crystal panel. At this time, the power of the system is not turned off. After that, most camera operations are not accepted. Operations accepted at this time include battery replacement, PC card replacement, and barrier (role of a main switch for camera operation) off.

Safety LB in step 101
If it is not Safety LB in the check, the Safety LB check is continuously performed at a constant cycle until SW1 is released or SW2 is pressed. This fixed period is approximately 200 milliseconds. When SW1 is released or SW2 is pressed (step 10).
2) End another task (step 103). This other task indicates another program that is running almost simultaneously with the main flow of the shooting sequence due to task switching of the OS.

Saf after the load test in step 100
In the safety LB check, the safety LB check is performed by temporarily increasing the load of the power supply circuit 15 in FIG. As the temporary load at this time, the power load of the optical block 1 and the imaging block 2 in FIG. 1 is expected.

In the above step 100, Safety LB
If Safety LB is detected in the check,
The imaging sequence is ended without turning on the power to the above-described optical block 1 and imaging block 2, and LB is displayed.
If it is not Safety LB in step 100, power is turned on to each of the optical and imaging blocks 1 and 2 in step 110, and the preparation for shooting operation is performed. This step 110
This process will be described later in detail with reference to FIG.

When the processing in step 110 is completed, the optical block 1 to the digital signal processing section 5 shown in FIG. 1 enter a movie operation state, and an AF (Auto Focus)
AE (Auto Exposures) / AWB (Auto White Balanc)
Preparation for the control in e) is completed. And step 120
TTL using only CCD sensor by AF control
AF is performed.

In this AF system, an area near the center of all the pixels of the CCD is designated as a distance measurement area to the signal processor 21 in FIG. 2, and the integrated value of the image data in that area is used as AE data. AF
Data for Then, first, a simple AE is performed prior to the AF, and the AF is adjusted in an appropriate exposure state.

What should be emphasized here is that in the simple AE described above, an appropriate exposure is adjusted for AF in a pixel area equivalent to the pixel area to be measured. In other words, even if there is a subject having a brightness deviating at the upper portion, the lower portion, or the like of all pixel regions, the exposure is adjusted by ignoring the subject and AF is performed accurately. As a result, appropriate distance measurement of the target pixel area can be performed.

When the AF control in step 120 is completed, a green LED is turned on as a completion mark. Subsequently, the AE and AWB control in step 130 is executed. The AE system and the AWB system are operating at approximately the same time with the different tasks described above.

In the AE system, first, the area is specified again to the signal processor 21 in FIG. 2 in order to meter the image data of a wide area different from the pixel area used in the above-described distance measurement. That is, the photometry window is switched.
The area at this time is set wide so as to cover almost the entire screen.

In this AE system, the exposure is adjusted so as to obtain an appropriate EV value while correcting the AV value without changing the TV value based on the photometric data. That is, in the AE of step 130, the shutter speed is kept constant, and the exposure is controlled so as to be within an appropriate exposure range while changing the aperture.

On the other hand, in the AWB system, 1 / of the entire screen
The colorimetry is performed at a plurality of locations in a relatively small area of about 16. For example, the colorimetry is performed at a total of eight locations including four corners at the top, bottom, left and right and four locations near the center. The colorimetric data of each block is limited in range, and data outside a certain range is not referred to.

As a result, it is possible to remove a portion that the user does not want to measure as AWB, for example, a portion of a dark-colored subject or a portion where the color is incorrect due to excessive luminance. Then, statistics of data within the range are obtained, and the white balance of the subject is adjusted more accurately. Further, the AWB system repeats reading of the colorimetric data of the area of the eight blocks five times to calculate white balance correction data.

Next, as shown by the condition judgment in step 140, when the user keeps pressing only the release switch SW1, AE and AWB continue to operate. Accordingly, it is possible to follow the case where the framing of the camera is changed while the SW1 is pressed or the case where the proof of the subject is changed. As a result of the condition determination in step 140, if SW1 is released or some other cancel occurs, the process proceeds to the end of step 141, and the photographing operation is stopped.

When the switch SW2 is pressed, the main exposure of step S150 is executed. This step 150
The actual exposure will be described in detail later with reference to FIG. 5. However, in brief, the exposure is switched to the exposure mode by the CCD, the shutter is released, and the image data for one screen is stored in the memory at once with the CCD transfer. 6 is transferred.

Subsequently, in step 160, LB detection is prohibited and signal processing is performed. Here, the raw image data on the memory is read out every several lines, and the digital signal processing unit 5 converts the raw image data into JPEG-compressed image data. Perform image processing.

The LB detection referred to here is the above-described Sa
Unlike the safety LB check, Safety L
The power supply voltage lower than the B check is detected, and the system power is immediately turned off when the LB is detected. This is a task (program) that has been operating at all times since the system was turned on regardless of the imaging sequence.

Therefore, at this time, the purpose of prohibiting the detection of the LB is to perform the signal processing (for example, JPE) for the LB.
This is to prevent interruption in an incomplete file state (while the G file is being written to a PC card or the like). When the signal processing is completed, the LB detection is started again. During the signal processing, BUSY characters are displayed on the liquid crystal panel.

Subsequently, the remaining amount calculation and the next number display in step 170 are executed, and the Safety LB check in step 161 is executed in another task. Steps 161 to 163 perform the same processing as steps 101 to 103 described above, respectively.
Description is omitted.

In the remaining capacity calculation in step 170, the remaining capacity after writing the file to the internal recording unit 7 or the medium of the PC card is obtained. At that time, the liquid crystal panel switches from the BUSY mark during signal processing to the next file number.

Next, in the condition judgment of step 180, SW
Detect if 1 has been released. If released
After the post-processing of this processing routine, the power of the optics and the imaging blocks 1 and 2 is turned off, and the percentage of the remaining amount is displayed on the liquid crystal panel (step 191). And step 19
At 2, the photographing process ends. At this time, do not turn off the power of this system immediately, but wait for a certain period and then turn off. This is so that the operation can be started immediately by reacting the next time the switches are pressed again.

In step 180, the condition of SW1
If has not been released, the process proceeds to step 190 for condition determination. In step 190, it is detected that SW2 is released and pressed again (re-pressed). This is S
This is because the process returns to step 180 when W2 is continuously pressed in the previous state or when only SW2 is released.

That is, steps 180 and 190 are looped to wait until SW1 is released or SW2 is pressed again. When the switch SW2 is pressed again, the main exposure in step 150 is executed again. If the switch SW2 is pressed again, the processing of steps 150 to 190 is repeated.

Next, the internal flow of the power supply of the image pickup / optical block and the preparation of the photographing operation in step 110 will be described in detail with reference to FIG. In the flow of FIG. 4, in step 201, the initial setting of the data interface unit 20 of FIG. 2 is performed. Specifically, the optical block 1
Before turning on the power of the imaging block 2, the state of each drive pulse signal is set to a low level, the drive pulse signal inside the data interface unit 20 is set to a predetermined state, and the flow of image data is controlled. It is set in advance.

Subsequently, in step 202, the power of the optical and imaging blocks 1 and 2 is turned on. And step 203
The setting of the pulse for imaging is performed, and the setting for reading the field of the CCD and the setting of the pixel size for driving in synchronism with the pseudo TV signal are performed. In this system, 5
A high-quality image is signal-processed using a 70,000-pixel sensor, but in the shooting preparation stage of SW1, TTL AF / A
It is necessary to drive a movie to perform E.AWB.

For this reason, when SW1 is ON, the minimum necessary pixel data is read without reading the data of all the pixels. Therefore, for that purpose, a pixel size for driving in a pseudo TV signal synchronization is set, and the CCD is driven.

After the pulse setting in step 203 is completed, the initial setting of the aperture and the electronic shutter is performed in step 204. Here, an intermediate aperture state is set as the initial aperture, and the electronic shutter is also set to the intermediate operation position of the mechanical shutter during the main exposure. For example, the aperture is set to 4 with an Av value, and the electronic shutter is set to 7 with a Tv value.

Next, in step 205, the main clock is switched, and the basic clock of the entire system is switched from the clock oscillating in the circuit inside the data interface unit 20 to the clock oscillating in the imaging block. This is to protect the image pickup circuit which is susceptible to noise from noise such as clock distortion and obtain high image quality, and to synchronize the entire system with a drive pulse centered on the image pickup circuit.

Next, in step 206, the movie operation is set, and not only the driving of the imaging block 2 but also the settings of the A / D converter 4, the data interface unit 20, and the signal processor 21 are set so as to correspond to the movie operation. I do. Specifically, the CCD output signal of the movie from the imaging block 2 is converted into a digital signal by the A / D converter 4, and the digital signal is directly input to the signal processor 21.

The signal processor 21 processes the input digital signal in real time, and executes AF / AE
・ Calculate necessary data by AWB or the like. The calculated data is sent to the MPU 3 through the data interface unit 20 and the ADD bus 12 by serial communication. In other words, the data is read out when the MPU 3 is needed. Therefore, in step 206, setting preparation for this is performed.

Next, at step 207, AF / AE /
MP for each AWB system to operate in MPU3
The environment setting inside U3 is performed. For example, DR of memory 6
An area with AM can be secured in the work area, AF / A
Each of the E and AWB systems sets an image processing area to the signal processor 21 and the signal processor 21
Environment setting for holding the image processing data from the memory 6 in the memory 6.

Finally, at step 208, the DMA at the time of the main exposure
Preparation is performed, and an image data saving area of the DRAM is secured for the case where image data of all the pixels of the CCD is DMA-transferred to the DRAM of the memory 6 during the main exposure. The image data save area has a list structure for each line, and has a data structure that allows reading and erasing access in units of lines when performing post-signal processing.

Next, the internal flow of the main photographing exposure in step 150 of FIG. 3 will be described in detail with reference to FIG.

When SW2 is pressed in step 140 of FIG. 3, the main exposure routine of photographing in step 150 is executed. First, in the flow of FIG.
At 11, the Safety LB check is performed after the load test. The load test at this time is different from the load test at step 100 in FIG. 3 and is a circuit (eg, a signal processor or a JP) used for signal processing and a load for driving the medium of the PC card.
A load test is performed in consideration of the operation load of the EG compression circuit.

Then, immediately after that, the Safety LB check is performed. If the result of the load is Safety LB, the subsequent processing is not executed, but the processing is immediately terminated and the LB is displayed on the liquid crystal panel. If it is not LB, the remaining amount is checked in step 212, and the recording medium (built-in recording unit or PC
Card).

Here, the file size created by the signal processing is calculated and predicted based on the current shooting state, and it is checked whether one or more images can be shot. When one or less, 0 Sho
t is displayed on the liquid crystal panel, the photographing process is terminated, and the red LED blinks at 8 Hz as an error mark while the release switch is pressed. If it is not 0 Shot, an abnormality of the switches is detected in step 213, and when an abnormality occurs, the red LED blinks at 8 Hz and the error content is displayed on the liquid crystal panel.

The abnormality of the switches means that the present system enables color image recording and high-resolution black-and-white recording. If an abnormality occurs in the changeover switch and it is in an intermediate state, it is detected. If there is no abnormality in the switches in step 213, a cancel check is performed in step 214. The cancellation check is to check whether a user operation for interrupting the shooting operation has been performed.

The user operation for interrupting the photographing operation is specifically described. The barrier can be closed, the dial can be changed, or the lid of the PC card can be opened. For example, a case where switching is performed is given. When such a cancel operation is performed, the photographing process is immediately terminated.

If the cancellation has not been performed, the self-timer SW is checked at step 215. When the self-timer state is detected by the self-timer SW check in step 215, the self-timer operation is executed in the next step 216. This self-timer operation refers to the AF on the front of the camera.
The infrared LED for correction blinks for a certain period of time to inform the user on the subject side that the camera is in the self-timer state. Two seconds before the main exposure, the LED is blinked from 2 Hz to 8H.
The display is switched to blinking z to notify the user that the photographing is about to be performed.

After the operation of the self-timer in step 216 or when the self-timer SW is not in the self-timer state in step 215, the step 217 is executed.
Then, an operation start OK signal of SW2 is executed. This is SW
A flag for starting the operation 2 is set, so that it cannot be canceled until the signal processing is completed thereafter. Then, by executing a cancellation check in step 218, it is checked again whether or not cancellation has occurred before step 217. As a result, it is possible to avoid missing the cancellation.

Next, in step 219, a resetting operation at the time of photographing is repeatedly executed. This is to prepare for photographing when photographing is repeatedly performed after the processing of step 190 in FIG. 3 described above. Specifically, the operations of steps 216 to 218 shown in FIG.
The setting for reusing the F, AE, and AWB data is performed.

Therefore, SW2 after the first SW1 operation
No operation is performed in shooting by the operation of. Next, in step 220, the complete flash charging before photographing is performed by the flash charging after the SW2 operation. At the same time, the charging related LED mark and the low luminance warning LED mark are turned off.

Then, in step 221, Safety
An LB check is performed to check whether the LB has been reached due to battery consumption due to flash charging. Thereafter, in step 222, AE immediately before the main exposure is performed. This is SW
1: While the AE at the time of ON is simple exposure control by aperture control, exposure measurement is performed again from that state, and the shutter speed is finely controlled so as to finally obtain an appropriate exposure for photographing. Preparation. Thereby, the final shutter speed is determined.

At this time, if it is determined that the subject is dark and has low brightness, or if it is in the strobe forced light emission mode,
In step 223, the EF system operates to detect the presence or absence of flash photography. Then, in step 224, the pre-flash of the strobe is performed, and the exposure level at the time of the pre-flash is measured. Then, the flash emission time at the time of the main exposure is calculated from the data result.

Subsequently, in step 225, the flash emission time is set when the shutter speed of the main exposure is set, and in step 226, the flash emission, mechanical shutter control, and CCD exposure control are performed in a timely manner. However, if the subject is bright or the strobe is turned off at the time of detecting the strobe shooting in the step 223, the operation of the step 224 is not executed, and the strobe is not emitted even in the main exposure of the step 225.

Then, at the time of the next CCD data reading, DMA of image data for all pixels is performed from the A / D converter 4 to the DRAM of the memory 6 through the data interface unit 20. Finally, step 227
When the DMA is completed, a signal flag is set, and the signal processing of step 160 in FIG. 3 is executed.

As described above, in the present embodiment, the imaging block 2 capable of reading an arbitrary image area from the CCD, the drive pulse generation circuit thereof, and the A / D converter 4 for converting the read image data into a digital signal. A digital signal processing unit 5 having a signal processor 21 capable of calculating necessary information from a digital image signal to AF / AE / AWB; and a memory 6 capable of temporarily saving data.
By providing the MPU 3 that can freely control those circuits, the AF / AE at the time of SW1 operation of the release switch is provided.
AWB processing can be improved.

Further, in addition to the above configuration, by providing a power load test circuit for each unit and a low battery detecting means for checking a plurality of power supply voltage levels, it is possible to perform various types of low battery interruption processing in the low battery operation in the photography operation. Thus, it is possible to flexibly cope with various photographing operations.

[0085]

As described above, according to the present invention,
There is an effect that it is possible to flexibly cope with various photographing operations.

That is, when the battery is extremely weak, the power of the system is immediately turned off so as not to put a useless load on the battery. By providing a plurality of battery check means such that a warning is issued, the operation of the system can be safely terminated depending on the state of the battery.

Further, by performing a load test and performing a battery check before turning on the power of the optical and imaging blocks immediately after the switch SW1 is turned on, the power of the optical and imaging blocks is not turned on when the battery is weak. In addition, the imaging operation can be ended without imposing a useless load on the battery.

Further, a load test is performed immediately before the signal processing after SW2 is turned on to check the battery, and at the same time, a low battery is not detected during the signal processing.
Also, by prohibiting the charging of the strobe during signal processing, the power consumption during signal processing is reduced, so that the battery does not suddenly weaken during signal processing and does not become a low battery. As a result, a complete image file can be created without shutting down the system during signal processing and without interrupting signal processing in an incomplete state.

Also, when SW1: ON AF, the AF
AE in the image area for
Perform F. After completion of AF, AE is performed in a wide image area of almost the entire area, and actual exposure shooting is performed with proper exposure. By changing the AE evaluation image area in different cases, the accuracy of AF is improved. And a high quality image with proper exposure can be obtained.

Also, at the time of SW1: ON AWB, by measuring the color at a plurality of portions of the screen with a relatively small image area, an effective area as the white balance data of the subject can be selectively obtained, and the white with good precision can be obtained. A balance can be made.

Further, by simultaneously executing the AE and the AWB after the AF, the photographing operation becomes faster, and the release time lag in the photographing can be improved.

Further, after taking the image with SW2: ON after SW1: ON (after signal processing), release SW2 only and release SW2 again.
Is turned on, the next photographing (main exposure and signal processing) can be performed immediately while the state of the previous AF, AE, and AWB is maintained without redoing the AF, AE, and AWB. This makes it possible to shorten the photographing time when photographing repeatedly, and to perform different framing and photographing of different subjects under the same photographing conditions such as AF, AE, and AWB. This is effective when a panoramic image is created later.

Further, the photographing preparation stage of the SW1 (AF / AE)
・ Including AWB), instead of reading out all the pixels of the CCD, read out the image data of a part of the area in a movie state to speed up each operation of SW, such as AF, AE, AWB, etc., and improve the release time lag. can do.

In the state of SW1: ON only, user cancellation by camera operation is accepted, and SW2:
The user cannot be canceled during the ON signal processing. Thus, a complete image file can be created without interrupting signal processing in an incomplete state. Furthermore, it is possible to ensure that the user cancellation has occurred immediately before the signal processing, so that the user cancellation is not missed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a system configuration of a camera according to the present invention.

FIG. 2 is a block diagram showing an internal configuration of a digital signal processing unit in FIG. 1;

FIG. 3 is a diagram illustrating a main flow of an imaging sequence according to the embodiment.

4 is a diagram showing a detailed flow of imaging / optical power-on and preparation for an imaging operation in FIG. 3;

FIG. 5 is a diagram showing a detailed flow of main photographing exposure in FIG. 3;

FIG. 6 is a block diagram showing a configuration of a conventional digital camera system.

[Explanation of symbols]

 Reference Signs List 1 optical block 2 imaging block 3 MPU (control means) 4 A / D converter (converter) 5 digital signal processing unit 6 memory (storage means) 7 built-in recording unit 10 strobe unit 13 operation unit 14 battery (built-in power supply) 15 power supply circuit

Claims (10)

[Claims] An image pickup means for converting a photographed subject image into an electric image signal, an A / D converter for converting an analog image signal from the image pickup means into a digital signal, and a predetermined signal for the digital signal. A signal processing means for performing the signal processing described above, wherein predetermined information for photographing is obtained by the processing of the signal processing means. 2. The camera according to claim 1, wherein, as predetermined information for photographing, photometric information for focus adjustment and photometric information for exposure adjustment are respectively obtained from different areas of the imaging means. 3. The camera according to claim 1, wherein colorimetric information of the image is obtained from a plurality of image areas of the image pickup means as predetermined information for photographing. 4. The camera according to claim 3, wherein an image area having valid data is selected from a plurality of colorimetric data. 5. The camera according to claim 1, wherein photometric information for exposure adjustment and colorimetric information of an image are simultaneously obtained as predetermined information for photographing. 6. The method according to claim 1, wherein after obtaining predetermined information for photographing, actual photographing is performed and the digital image signal from the signal processing means is stored in the storage means. camera. 7. The camera according to claim 6, wherein after obtaining predetermined information for photographing, only main photographing is repeated. 8. The camera according to claim 7, wherein a cancel operation of the user is accepted during an operation of obtaining predetermined information for photographing, and no cancel operation is accepted during the actual photographing. 9. The method according to claim 1, wherein the operation is interrupted when the voltage of the built-in power supply drops below a predetermined value during the operation of obtaining predetermined information for photographing. camera. 10. The method according to claim 1, wherein the processing being executed is interrupted when the voltage of the internal power supply drops below a certain threshold value, and the power supply switch is turned off when the voltage drops below a lower threshold value. The camera according to any one of claims 1 to 8, wherein