JP2003102018A - Electronic still camera, imaging method, computer- readable storage medium, and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic still camera that can minimize the occurrence of erroneous white balance adjustment caused when a condition of an illumination light source at the adjustment is different from that at an actual photographing point of time in the white balance adjustment for the hybrid system of the electronic still camera. SOLUTION: The electronic still camera provided with a white balance adjustment means for performing white balance adjustment based on a photographed image, measures number of photographed images and an elapsed time from a prescribed point of time, discriminates the reliability of a white balance control signal stored at the prescribed point of time and can inform a user about it when the reliability is low.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic still camera, an imaging method, a computer-readable storage medium and a computer program, and is particularly suitable for use in an electronic still camera equipped with white balance adjusting means.

[0002]

2. Description of the Related Art As an automatic white balance adjusting means for a conventional electronic still camera, an external sensor system, TTL
(Through The Lens) method is generally used.

The external measurement sensor method is for performing white balance correction using color temperature data obtained by measuring the color of external light, and the TTL method is for white balance correction based on an image output signal of an image sensor by a predetermined algorithm. The white balance of the entire image output is corrected after extracting the luminance data of the reference R, G, and B specific pixels.

However, the external measurement sensor system has a problem that the accuracy of white balance adjustment is significantly deteriorated when the light source for irradiating the main body of the image pickup device is different from the light source for irradiating the subject. Further, in the TTL method, when the subject is a large area of chromatic color and most of the screen is occupied by a single color, the white balance adjustment accuracy is also degraded. was there.

Further, in the above-mentioned TTL method, a white subject is imaged in advance under the illumination light source at the time of actual photographing, and the white balance adjustment value is calculated based on the image data output from the image pickup device at that time. There is also known a white balance adjustment method called a so-called blank paper white balance mode in which settings are made and white balance adjustment is performed based on a white balance adjustment value so that the color temperature of a subject on the screen approaches white.

However, in the white paper shooting white balance mode, the white balance adjustment value at the time of capturing the white subject image data is set to a fixed value, and hence the white balance adjustment value under illumination light for actual shooting thereafter is performed. If the illumination light at the time of setting is not the same condition, there arises a problem that accurate white balance adjustment cannot be performed.

On the other hand, as a means for solving these problems, there is a hybrid system using both the external measurement sensor system and the TTL system. The white balance correction using such a hybrid method is disclosed in Japanese Patent Application No. 2694620 by the present applicant.

[0008]

[Problems to be Solved by the Invention] Special Registration 2694620
In the hybrid method using both the external measurement sensor method and the TTL method in Japanese Patent Laid-Open Publication, white balance adjustment that compensates for the drawbacks of both methods is possible, so the above-mentioned problems can be solved.

However, in general, in order to accurately measure the color of the illumination light source around the main body of the image pickup apparatus by using the external measurement sensor, the external measurement side is set between the time when the shutter button is pressed and the actual exposure is started. It is necessary to detect the color temperature data of the illumination light source using the colorimetric sensor or the like and prepare for white balance control in advance. This causes a problem that the so-called release time lag increases, and as a result, there is a risk of missing a photo opportunity. Further, if a CCD or the like is used as the external measurement sensor, the problem of release time lag can be solved, but the problem of increased cost arises.

The present invention has been made in view of the above problems, and in the white balance adjustment by the hybrid method, the white balance adjustment value stored by using the data sampled by the external sensor in advance is the actual photographing value. The purpose is to minimize false white balance adjustment that occurs when the condition of the illumination light source at the time is different.

[0011]

According to another aspect of the present invention, there is provided an electronic still camera having a white balance adjusting means, wherein a white balance control signal for performing the white balance adjustment is set and stored, and the white balance control signal is stored. It is characterized in that the number of photographed frames from the time when the balance control signal is stored is measured, and when the measured number of photographed frames is equal to or more than a predetermined number, the fact is notified.

Another feature of the electronic still camera of the present invention is that in an electronic still camera having a white balance adjusting means, a white balance control signal for performing the white balance adjustment is set and stored. When the number of photographed frames and the elapsed time from the time of storing the white balance control signal are measured, and at least one measured value among the measured number of photographed frames or the elapsed time exceeds a predetermined value, the fact Is provided for notifying the user.

Another feature of the electronic still camera of the present invention is that it has an image pickup device for receiving a subject image light transmitted through a photographing lens and electronically picking it up, and an image signal obtained from the image pickup device. Generating a first white balance control signal for white balance adjustment using
A second white balance control signal for white balance adjustment is generated by using the signals obtained from the white balance detecting means and the color measurement sensor other than the image sensor.
An electronic still camera comprising: a white balance detecting means, and a white balance adjusting means for determining a final white balance adjustment value based on white balance control signals obtained from the two white balance detecting means, Measuring means for setting a second white balance control signal in advance by using the second white balance detecting means, and measuring the number of frames taken after the second white balance control signal is stored and set; When the number of photographed frames measured by the measuring unit is equal to or larger than a predetermined number of frames, a notifying unit for notifying the fact is provided.

Since the present invention is provided with the above technical means, the number of frames photographed is measured from the time when the second white balance control signal is stored, and the number is recorded based on the number of frames photographed. It is possible to determine the reliability of the white balance control signal. When the reliability is low (the number of frames to be photographed is larger than the predetermined number of frames), the notification unit is used to inform or warn the photographer so that erroneous white balance adjustment is minimized. It becomes possible to limit it.

Another feature of the electronic still camera of the present invention is that it has an image pickup device for receiving a subject image light transmitted through a photographing lens and electronically picking it up, and an image signal obtained from the image pickup device. Generating a first white balance control signal for white balance adjustment using
A second white balance control signal for white balance adjustment is generated by using the signals obtained from the white balance detecting means and the color measurement sensor other than the image sensor.
An electronic still camera comprising: a white balance detecting means, and a white balance adjusting means for determining a final white balance adjustment value based on white balance control signals obtained from the two white balance detecting means, A first measurement in which the second white balance control signal is set in advance by using the second white balance detection means, and the number of frames to be photographed is measured from the time when the second white balance control signal is stored and set. Means, a second measuring means for measuring an elapsed time from the time when the second white balance control signal is set, and a measurement value measured by at least one of the measuring means is predetermined. When it exceeds the value, it is characterized by including a notifying means for notifying that effect.

According to another feature of the electronic still camera of the present invention, both the number of frames to be photographed and the elapsed time from the time when the second white balance control signal is stored are measured. It is possible to more accurately determine the reliability of the stored white balance control signal based on both the number data and the elapsed time data. When the reliability is low (when the number of shooting frames is greater than the predetermined number of frames, when a predetermined time has elapsed, or when both are established)
In addition, it is possible to minimize erroneous white balance adjustment by notifying and warning the photographer using the notifying means.

Further, according to another feature of the electronic still camera of the present invention, when the measurement value measured by at least one of the measuring means exceeds a predetermined value, the electronic still camera is set in advance. It is characterized in that it is provided with a canceling means for canceling the determination of the final white balance adjustment value by using the stored and set second white balance control signal.

Since the present invention comprises the above technical means, both the number of frames to be photographed and the elapsed time from the time when the second white balance control signal is stored are measured, and both the number of photographed frames and the elapsed time are recorded. Based on the above, the reliability of the stored white balance control signal can be determined, and if the reliability is low as a result, the notification means is used to notify or warn the photographer, and an erroneous external measurement is performed. By canceling the final determination of the white balance adjustment value using the sampling data from the colorimetric sensor, it is possible to minimize erroneous white balance adjustment.

Further, according to another feature of the electronic still camera of the present invention, the measurement value measured by at least one of the measuring means is changed during continuous photographing or the exposure value. However, it is characterized in that a prohibition means is provided for prohibiting the operation of the releasing means when the predetermined value is exceeded during exposure blanketing for continuously exposing and photographing a plurality of frames.

Since the present invention is provided with the above-mentioned technical means, when the releasing means is operated during continuous shooting or during exposure blanketing for continuously exposing and shooting a plurality of frames while changing the exposure value, the operation is performed. By operating the prohibition function to prohibit, it is possible to eliminate a sudden change in the white balance adjustment value from the middle of the continuously shot images, so it is possible to record an image with white balance adjustment that does not cause discomfort. Becomes

The image pickup method of the present invention is an image pickup method of an electronic still camera having a white balance adjusting step,
The white balance control signal for performing the white balance adjustment is set and stored, and the number of shooting frames from the time of storing the white balance control signal is measured, and the measured number of shooting frames is equal to or more than a predetermined number. It is characterized in that when this happens, the fact is notified.

According to another feature of the image pickup method of the present invention, in the image pickup method of an electronic still camera having a white balance adjustment step, a white balance control signal for performing the white balance adjustment is set and stored. At the same time, the number of photographed frames and the elapsed time from the time of storing the white balance control signal are measured, and when at least one measured value among the measured number of photographed frames or the elapsed time exceeds a predetermined value, the And a notification step of processing so as to notify the effect.

Further, according to another feature of the image pickup method of the present invention, the image pickup device has an image pickup device which receives the object image light transmitted through the photographing lens and electronically picks it up, and uses the image signal obtained from the image pickup device. And a second white balance adjustment step using a signal obtained from a colorimetric sensor other than the image sensor to generate a first white balance control signal for white balance adjustment. A second white balance detection step of generating a white balance control signal and a white balance adjustment step of determining a final white balance adjustment value based on the white balance control signals obtained from the two white balance detection steps. An imaging method of an electronic still camera provided with,
A measurement step of setting a second white balance control signal in advance using the second white balance detection step, and measuring the number of frames taken from the time when the second white balance control signal is stored and set; When the number of photographed frames measured in the measuring step is equal to or larger than the predetermined number of frames, a notification step of processing to notify that effect is provided.

Further, according to another feature of the image pickup method of the present invention, the image pickup device has an image pickup device which receives the object image light transmitted through the photographing lens and electronically picks it up, and uses an image signal obtained from the image pickup device. And a second white balance adjustment step using a signal obtained from a colorimetric sensor other than the image sensor to generate a first white balance control signal for white balance adjustment. A second white balance detection step of generating a white balance control signal and a white balance adjustment step of determining a final white balance adjustment value based on the white balance control signals obtained from the two white balance detection steps. An imaging method of an electronic still camera provided with,
A first measurement in which the second white balance control signal is set in advance using the second white balance detection step, and the number of frames to be photographed is measured from the time when the second white balance control signal is stored and set. And the second
When the measurement value measured in the second measurement step of measuring the elapsed time from the time of setting the white balance control signal of No. 1 and at least one of the measurement steps exceeds a predetermined value And a notification step of processing so as to notify that effect.

Further, according to another feature of the image pickup method of the present invention, at least one of the above measuring steps is used.
When the measured value measured in one of the measuring steps exceeds a predetermined value, canceling the determination of the final white balance adjustment value using the previously stored second white balance control signal is released. It is characterized by including steps.

Further, according to another feature of the image pickup method of the present invention, at least one of the above measuring steps is used.
If the measurement value measured in one measurement process exceeds the specified value during continuous shooting or during exposure blanketing that continuously exposes multiple frames while changing the exposure value, the release process is activated. It is characterized by having a prohibition process for prohibiting.

The storage medium of the present invention is characterized by recording a program for causing a computer to function as each of the above-mentioned means. Another feature of the storage medium of the present invention is that a program for causing a computer to execute the method described above is recorded.

Further, the computer program of the present invention is characterized by causing a computer to execute the method described above.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the electronic still camera of the present invention will be described with reference to the attached drawings. As shown in FIG. 2, in the general electronic still camera 1, the incident portion of light to the colorimetric sensor 25, which is the second white balance detecting means, faces the front (subject side) to the upper position on the front side of the camera. It is provided in its original state.

Next, the electronic still camera 1 of the present embodiment
The configuration of will be described. FIG. 1 is a block diagram showing a schematic configuration of the entire electronic still camera according to the present embodiment.

The light ray L from the subject is received by the image pickup device 13 via the taking lens 11 and the diaphragm device 12. The image pickup element 13 is an element that converts received light into an electric signal, and is a solid-state image pickup element such as a CCD (charge transfer device) or a MOS device.

A preprocessing circuit 14 includes a CDS circuit for removing output noise of the image pickup device 13 and a non-linear amplification circuit for performing A / D conversion. 15 is a preprocessing circuit 1
4 is an A / D converter for converting the analog output from 4 into a digital signal, and the digitally converted signal is guided to the image processing circuit 16 which is also the first white balance detecting means.

The image processing circuit 16 performs image preprocessing such as contour compensation and gamma correction, and outputs it to the memory control circuit 17. Further, the image processing circuit 16 generates a first white balance control signal for performing white balance, and this control signal is transmitted to the control device 21 which is also white balance adjusting means.

The memory control circuit 17 includes an image processing circuit 16
In addition to storing the first white balance control signal generated in step 1 in the internal storage device 20 which is a storage means, the image signal generated in the image processing circuit 16 is transferred to the outside via a interface circuit 18 such as a memory card. It is stored in the storage device 19. The internal storage device 20 has a second
The white balance control signal is stored and stored.

The diaphragm device 12 is controlled by the control device 21 by the output from the photometric sensor 22 which measures the brightness of the subject. In FIG. 1, the photometric sensor 22 is the photographing lens 1.
Although one provided separately for one optical axis is shown, a so-called TTL system formed coaxially with this may be used.

Next, the colorimetric sensor 25 which is the second white balance detecting means will be described below. In the colorimetric sensor 25, external light around the colorimetric sensor 25 enters the R light receiving element 32R, the G light receiving element 32G, and the B light receiving element 32B through the diffusion plate 31, and the red component (Rb) of the incident light,
The green component (Gb) and the blue component (Bb) are output. These color component signals are logarithmically compressed by the logarithmic compression circuit 33 and output as logRb, logGb, and logBb.

Next, in the subtraction circuit 34 and the subtraction circuit 35,
og (Rb / Gb) and log (Bb / Gb), respectively, and the decompression circuit 36 performs inverse log conversion into Rb / Gb and Bb / Gb.

Then, via the current-voltage conversion circuit 37,
It is digitally converted by the A / D converter 24 and output to the control device 21 as a second white balance control signal.

Here, SW1 is a shooting preparation switch and SW
Reference numeral 2 is a shooting start switch. Further, reference numeral 26 is a switch for fetching externally measured white balance data, and when this switch is turned on, the previous value of the second white balance control signal stored in the internal storage device 20 is once erased.

Then, the colorimetric sensor 25 is further activated,
Based on the ambient light data sampled from its surroundings, A
The value generated as the second white balance control signal via the / D converter 24 and the control device 21 is stored again in the internal storage device 20.

A white balance adjusting circuit 21b is provided in the control device 21, and the image processing circuit is based on the second white balance control signal stored in the internal storage device 20 and the captured image information obtained from the image sensor 13. 16 is combined with the first white balance control signal generated by 16 to calculate the final white balance adjustment value, and the image processing circuit 1
The image is again transmitted to the device 6 and the final image processing is performed.

In the control device 21, the number of frames to be photographed after the ON signal of the switch 26 for taking in the externally measured white balance data is detected, and the measuring means 21a for counting the elapsed time and the measuring means 21a. Depending on the reliability of the second white balance control signal determined based on the result, the canceling means (not shown) for canceling the calculation of the white balance adjustment value, and further, the value of the measured value measured by the measuring means 21a is Also provided with a prohibiting means (not shown) for prohibiting the operation of the releasing means when a predetermined value is exceeded during continuous shooting or during exposure blanketing for continuously exposing and shooting a plurality of frames while changing the exposure value. There is.

The external display device 28 is a liquid crystal element for displaying various information regarding photographing, and the control device 21.
The determination information of the reliability of the second white balance control signal, which is determined based on the result of the measuring unit 21b, is also used as a notifying unit for notifying or warning the photographer.

Next, a series of photographing operations of the electronic still camera configured as described above will be described with reference to a flowchart. FIG. 3 is a flowchart showing the entire sequence of the shooting operation.

First, in step S101, it is determined whether or not the photographing start switch SW2, which is a release button of the camera, is pressed to turn on the photographing preparation switch SW1. As a result of the determination, if it is ON, the process proceeds to step S102, and if the shooting preparation switch SW1 is OFF, the process returns to step S101 to check the state of the shooting preparation switch SW1 again.

In step S 102, the photometric sensor 22 measures the brightness of the subject, and the brightness information of the subject is output to the control device 21.

Next, in step S103, the external preset data, which is the second white balance control signal, is previously stored as the external preset mode in the internal storage device 20.
To determine whether or not it is stored in. If the result of determination is that external measurement preset data has already been stored, step S1.
04, the process proceeds to step 106 if the external measurement preset data is not stored.

In step S104, it is determined whether or not the value of the frame number measuring counter (FC), which is the measuring means 21a, exceeds a predetermined frame number setting value FX, or the value of the elapsed time measuring counter (TC) is within a predetermined time period. It is determined whether or not the set value TX is exceeded.

As a result of this determination, if at least one of the values exceeds the predetermined value, the process proceeds to step S105. If none of the values exceeds the predetermined value,
Jump to step S110.

In step S105, the photographer is informed that the value of the frame number counter (FC) or the value of the elapsed time counter (TC) has exceeded the set value, by using the notification means such as the external display device 28. Then, the notification is given, and then the process proceeds to step S110.

On the other hand, in step S106, the color temperature around the colorimetric sensor 25, which is the second white balance detecting means, is measured, and in step S107, the colorimetric sensor 2 is measured.
The second white balance control signal output from
The data is stored in the internal storage device 20 via the control device 21.

Next, in step S108, the measuring means 2
The value of the frame number measuring counter (FC) and the value of the elapsed time measuring counter (TC) which are 1a are cleared to 0, and then, in step S109, the counting of the elapsed time measuring counter (TC) of the measuring means 21a is started. Let

In step S110, it is determined whether or not the photographing start switch SW2 is turned on. If the result of this determination is that the shooting start switch SW2 is ON, processing advances to step S111, shooting is performed, and image data is captured. If the shooting start switch SW2 is off, the process returns to step S101.

Subsequent to the photographing in step S111, in step S112, the image processing circuit 1 is set on the basis of the photographed image signal obtained from the output of the image sensor 13 in the internal auto mode.
The first white balance control signal is generated by 6 and is stored in the internal storage device 20.

Further, in step S113, the data of both the first white balance control signal and the second white balance control signal stored in the internal storage device 20 are read to the white balance adjustment circuit 21b, and the final white balance control signal is read. The balance adjustment value is calculated and transmitted to the image processing circuit 16, and the image preprocessing is performed again.

However, when the value of at least one of the frame number counter (FC) and the elapsed time counter (TC) exceeds a predetermined value in step S104, the final white balance adjustment value is calculated. In this case, the second white balance control signal is not taken into consideration, and only the first white balance control signal is used for the determination.

In step S114, step S113
The image data processed according to the white balance adjustment value calculated in step 3 is recorded in the external recording device 19.

In step S115, the value of the frame number counter (FC), which is the measuring means 21a, is incremented by setting one frame as 1.

Next, an interrupt routine when the photographer selects the external measurement preset mode at an arbitrary timing will be described with reference to the flowchart of FIG. This interrupt routine is a sequence that starts when the photographer turns on the external measurement white balance data acquisition switch 26 at a timing different from the main photographing sequence flow described in FIG.

In step S201, it is determined whether or not the capture switch 26, which is the operation of starting the externally measured white balance data, has been pressed. If the result of this determination is that the fetch switch 26 has been pressed, the subroutine of this interrupt starts and proceeds to step S202, and if the fetch switch 26 has not been pressed, to confirm again, go to step S201. And wait.

In step S202, the color temperature around the colorimetric sensor 25, which is the second white balance detecting means, is measured. In step S203, the second white balance control signal output from the colorimetric sensor 25 is measured. , To the internal storage device 20 via the control device 21.

In step S204, the values of the frame number counter (FC) and the elapsed time counter (TC), which are the measuring means 21a, are cleared to 0, and then step S2.
In 05, the counting of the elapsed time measuring counter (TC) of the measuring means 21a is started. When the above subroutine processing is completed, the process proceeds to step S206 and returns to the main routine.

Next, FIG. 5 is a flowchart showing the sequence of the photographing operation during continuous photographing or during exposure blanketing for continuously exposing and photographing a plurality of frames while changing the exposure value.

First, in the first step S301, it is determined whether or not the photographing start switch, which is the release button of the camera, is pressed to turn on the photographing preparation switch SW1. As a result of this determination, when the shooting preparation switch SW1 is turned on, the process proceeds to step S302. If the photographing preparation switch SW1 is off, the photographing preparation switch SW1 is checked again, and the process waits in step S301.

Next, in step S 302, the brightness of the subject is measured by the photometric sensor 22, and the brightness information of the subject is output to the control device 21.

Next, in step S303, it is determined whether or not the current shooting conditions are continuous shooting or exposure blanketing (hereinafter referred to as AEB) for continuously shooting a plurality of frames while changing the exposure value. To judge. As a result of this determination, if it is determined that continuous shooting or AEB is in progress, the process proceeds to step S311, and if it is determined that neither shooting is in progress, step S30.
Go to 4. In the case of the first frame in the normal shooting sequence, the determination flow of step S303 is ignored.

Next, in step S304, as the external preset mode, the external preset data which is the second white balance control signal is previously stored in the internal storage device 20.
To determine whether or not it is stored in. As a result of this judgment,
If the external measurement preset data is already stored, the process proceeds to step S305, and if the external measurement preset data is not stored, the process proceeds to step S307.

Next, in step S305, the measuring means 2
Whether the value of the frame number counter (FC) which is 1a exceeds a predetermined frame number set value FX, or whether the value of the elapsed time measurement counter (TC) exceeds a predetermined time set value TX. To judge. As a result of this determination, if at least one of the values exceeds the predetermined value, step S
The process proceeds to step 306, and if none of the values exceeds the predetermined value, the process jumps to step S311.

In step S306, the value of the frame number measuring counter (FC) or the elapsed time measuring counter (T
If the value of C) exceeds a predetermined value, the external display device 28
The photographer is notified by using such notification means, and then the process proceeds to step S311.

On the other hand, in step S307, the color temperature around the colorimetric sensor 25, which is the second white balance detecting means, is measured, and in step S308, the colorimetric sensor 2 is measured.
The second white balance control signal output from
The data is stored in the internal storage device 20 via the control device 21.

In step S309, the values of the frame number counter (FC) and elapsed time counter (TC), which are the measuring means 21a, are cleared to 0, and then step 31
At 0, the counting of the elapsed time measuring counter (TC) of the measuring means 21a is started.

Next, in step S311, it is determined whether or not the photographing start switch SW2 is ON. If the result of this determination is that the shooting start switch SW2 is ON, processing advances to step S312, shooting is performed, and image data is captured. In addition, the shooting start switch SW2 is OF
In the case of F, the process returns to step S301 again.

Subsequent to the photographing in step S312, in step S313, the image processing circuit 1 is set based on the photographed image signal obtained from the output of the image pickup device 13 in the internal measurement auto mode.
6, the first white balance control signal is generated almost simultaneously and is stored in the internal storage device 20.

Further, in step S314, under the normal photographing condition (single photographing), the data of both the first white balance control signal and the second white balance control signal stored in the internal storage device 20 are stored. Is read to the white balance adjustment circuit 21b, the final white balance adjustment value is calculated, and the final white balance adjustment value is transmitted to the image processing circuit 16 and the image preprocessing is performed again.

However, the number of frames is measured in step S305, neither in the continuous shooting in the step S303 or in the AEB shooting in which a plurality of frames are continuously exposed and shot while changing the exposure value. When the value of at least one of the counter (FC) and the elapsed time measurement counter (TC) exceeds a predetermined value, the second white balance control signal is added when calculating the final white balance adjustment value. Instead, it is determined only by the first white balance control signal.

On the other hand, in step S303, the shooting condition is either continuous shooting or AEB shooting in which a plurality of frames are continuously exposed and shot while changing the exposure value, and in step S305 Frame counter (F
If the value of at least one of C) and the elapsed time measurement counter (TC) exceeds a predetermined value, it is stored in the internal storage device 20 as in the case of the normal shooting condition (single shooting). The first white balance control signal and the second
Both of the white balance control signals of 1 are read to the white balance adjustment circuit 21b, the final white balance adjustment value is calculated and determined, and the final white balance adjustment value is transmitted to the image processing circuit 16 again and image preprocessing is performed.

Next, in step S315, step S
The image data processed according to the white balance adjustment value calculated in 314 is recorded in the external recording device 19.

Next, in step S316, the measuring means 2
The value of the frame number counter (FC), which is 1a, is counted up with 1 for one frame.

Next, in step S317, the current photographing conditions are confirmed again. As a result of this confirmation, if the shooting preparation switch SW1 or the shooting start switch SW2 is in the ON state, continuous shooting is in progress, or if it is in the middle of a predetermined number of shooting frames during AEB shooting, the process returns to step S301.

Further, when it is not in operation, that is, when the photographing preparation switch SW1 is in the OFF state, or when the AEB
If the shooting is not in progress, the main shooting sequence is once ended.

Next, when the photographer described in the flowchart of FIG. 4 selects the external measurement preset mode at an arbitrary timing, and the color measurement described in steps S107 and S308 of the flowcharts of FIGS. 3 and 5. One of the cases where the second white balance control signal output from the sensor 25 is set will be described with reference to the state of the display device shown in FIG.

FIG. 6 is one display example showing the display state of the external display device 28. When the external measurement white balance data acquisition switch 26 is turned on, the external measurement preset mode is selected, and the second white balance control signal output from the color measurement sensor 25 at an arbitrary timing is internally stored via the control device 21. When stored in the device 20, or when the external measurement preset data that is the second white balance control signal is not stored in the internal storage device 20 in advance during the normal shooting sequence, it is automatically output from the colorimetric sensor 25. When the second white balance control signal is stored in the internal storage device 20 via the control device 21, in either state, W in the upper left of FIG.
B. The L (white balance is locked) display lights up or blinks to notify the photographer.

As the notification means of the present invention, for example, the W
B. By flashing the L display, it is possible to notify the photographer. Further, for example, by displaying the measurement result of the number of frames and the elapsed time in the seven segment display area of FIG.
It is also possible to notify the photographer.

Although only the external display device has been described in this embodiment, for example, although not shown, it is possible to simultaneously display the photographed subject in an optical finder device for optically observing the photographed subject. The display means in the viewfinder and the color TFT liquid crystal capable of displaying the photographed image itself in color may be provided.

Furthermore, it is possible to obtain the same effect by using not only a visual display means but also a buzzer or a speaker that emits a warning sound by driving a piezoelectric element or the like.

The above embodiment is an example for explaining the configuration of the present invention in an easy-to-understand manner, and the present invention is not limited to the embodiment.

(Other Embodiments of the Present Invention) The present invention may be applied to a system including a plurality of devices or an apparatus including a single device.

Further, various devices are operated so as to realize the functions of the above-mentioned embodiments, and a computer in an apparatus or system connected to the various devices is transferred from a storage medium or a transmission medium such as the Internet. The program code of software for realizing the functions of the above-described embodiment is supplied through the computer, and the various devices are operated according to the program stored in the computer (CPU or MPU) of the system or apparatus. Are also included in the scope of the present invention.

Further, in this case, the program code itself of the software realizes the functions of the above-described embodiments, and the program code itself and means for supplying the program code to the computer, for example, such program. The storage medium storing the code constitutes the present invention. A storage medium for storing the program code is, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-R.
An OM, a magnetic tape, a non-volatile memory card, a ROM or the like can be used.

Further, not only the functions described in the above-described embodiments are realized by executing the supplied program code by the computer, but also the OS (operating system) in which the program code is operating in the computer. Alternatively, the program code is also included in the embodiments of the present invention when the functions shown in the above-described embodiments are implemented jointly by other application software or the like.

Further, after the supplied program code is stored in the memory provided in the function expansion board of the computer or the function expansion unit connected to the computer, the function expansion board or function expansion unit is instructed based on the instruction of the program code. The present invention also includes a case where the CPU or the like included in the above performs some or all of actual processing and the functions of the above-described embodiments are realized by the processing.

[0092]

As described above, according to the present invention, in the white balance adjustment by the hybrid system,
Minimize erroneous white balance adjustment that occurs when the white balance adjustment value stored using data sampled with an external sensor in advance differs from the illumination light source conditions at the time of actual shooting. You can Specifically, when the reliability of the white balance control signal stored in advance is low, a notification unit is used to notify or give a warning to the photographer to minimize erroneous white balance adjustment. Can be suppressed,
It is possible to obtain a good captured image without a feeling of strangeness. Furthermore, the reliability of the white balance control signal can be determined more accurately based on both the number of frames to be photographed and the elapsed time from the time when the color temperature data obtained in advance by the external sensor was stored. However, when the reliability is low, the notification means is used to notify or warn the photographer, and it is possible to minimize the occurrence of erroneous white balance adjustment. Images can be obtained. Furthermore, when the reliability of the white balance control signal stored in advance is low, the notifying means is used to give a warning or warning to the photographer, and the final sampling is made by using sampling data from an erroneous external colorimetric sensor. By canceling the determination of the effective white balance adjustment, it is possible to minimize the erroneous white balance adjustment and obtain a good captured image without a sense of discomfort. Furthermore, the final white balance adjustment release operation is prohibited during continuous shooting or when continuous shooting such as exposure blanketing in which multiple frames are continuously exposed and shot while changing the exposure value. Therefore, it is possible to prevent the adjustment value of the white balance from changing abruptly from the middle of the image, and it is possible to record the image with the white balance adjusted without a sense of discomfort.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention and showing a schematic configuration of an entire electronic still camera.

FIG. 2 is a diagram showing an embodiment of the present invention and showing an external arrangement configuration of a color measurement unit of a digital camera.

FIG. 3 shows an embodiment of the present invention and is a flowchart showing an overall sequence of a photographing operation.

FIG. 4 is a flow chart showing an interrupt routine when the external preset mode is selected at an arbitrary timing according to the embodiment of the present invention.

FIG. 5 is a flowchart showing an embodiment of the present invention and showing a photographing operation sequence in exposure blanketing during continuous photographing or exposing and photographing a plurality of frames continuously while changing an exposure value.

FIG. 6 is a diagram showing a display state of a display device according to the embodiment of the present invention.

[Explanation of symbols]

1 Electronic still camera 11 Shooting lens 12 Aperture device 13 Image sensor 14 Pre-processing circuit 15 A / D converter 16 Image processing circuit 17 Memory control circuit 18 I / F circuit 19 External storage device 20 internal storage 21 Control device 21a Measuring means 21b White balance adjustment circuit 22 Photometric sensor 24 A / D converter 25 Colorimetric sensor 26 Capture switch 28 External display device 31 Diffuser 32RR light receiving element 32G G light receiving element 32B B light receiving element 33 logarithmic compression circuit 34, 35 Subtraction circuit 36 Expansion circuit 37 Current-voltage conversion circuit

Claims (15)

[Claims] 1. An electronic still camera having a white balance adjusting means, wherein a white balance control signal for performing the white balance adjustment is set and stored, and the number of frames taken from the time when the white balance control signal is stored. The electronic still camera is characterized in that when the measured number of photographed frames is equal to or larger than a predetermined number of frames, the fact is notified. 2. An electronic still camera having a white balance adjusting means, wherein a white balance control signal for performing the white balance adjustment is set and stored, and the number of frames taken from the time of storing the white balance control signal. And an elapse time, and when at least one of the measured number of frames or elapsed time exceeds a predetermined value, an informing unit for informing that fact is provided. camera. 3. A first white balance control for adjusting a white balance by using an image pickup device for receiving a subject image light transmitted through a photographing lens and electronically picking up the image, and using an image signal obtained from the image pickup device. A first white balance detecting means for generating a signal, and a second white balance detecting means for generating a second white balance control signal for white balance adjustment using a signal obtained from a colorimetric sensor other than the image sensor. Means and a white balance adjusting means for determining a final white balance adjustment value based on white balance control signals obtained from the two white balance detecting means. A second white balance control signal is set in advance by using a white balance detection means, and the second white balance control signal is set. A measuring means for measuring the number of photographed frames from the time the memory control signal is stored and set; and a notifying means for notifying that when the number of photographed frames measured by the measuring means is a predetermined number or more. A characteristic electronic still camera. 4. A first white balance control for adjusting a white balance using an image pickup device for receiving a subject image light transmitted through a taking lens and electronically picking up the image, and using an image signal obtained from the image pickup device. A first white balance detecting means for generating a signal, and a second white balance detecting means for generating a second white balance control signal for white balance adjustment using a signal obtained from a colorimetric sensor other than the image sensor. Means and a white balance adjusting means for determining a final white balance adjustment value based on white balance control signals obtained from the two white balance detecting means. A second white balance control signal is set in advance by using a white balance detecting means, and the second white balance control signal is set. A first measuring means for measuring a number of photographic frame from the time of setting and storing the scan control signal, the second
When the measured value measured by the second measuring means for measuring the elapsed time from the time when the white balance control signal of (1) and at least one measuring means of the above-mentioned measuring means exceeds a predetermined value An electronic still camera, comprising: an informing means for informing that fact. 5. When the measurement value measured by at least one of the measuring means exceeds a predetermined value, the second white balance control signal stored in advance is used. The electronic still camera according to claim 3, further comprising a releasing unit that releases the determination of the final white balance adjustment value. 6. A measurement value measured by at least one of the measuring means is continuously photographed or during exposure blanketing for continuously exposing and photographing a plurality of frames while changing an exposure value. The electronic still camera according to claim 5, further comprising a prohibiting unit that prohibits the operation of the releasing unit when the predetermined value is exceeded. 7. An image pickup method for an electronic still camera having a white balance adjusting step, wherein a white balance control signal for performing the white balance adjustment is set and stored, and the white balance control signal is stored from the time when the white balance control signal is stored. An image pickup method characterized in that the number of photographed frames is measured, and when the measured number of photographed frames is equal to or larger than a predetermined number of frames, the fact is notified. 8. An electronic still camera image pickup method having a white balance adjustment step, wherein a white balance control signal for performing the white balance adjustment is set and stored, and the white balance control signal is stored from the time when the white balance control signal is stored. And a notification step of measuring the number of photographed frames and the elapsed time and, when at least one measured value out of the measured number of photographed frames or the elapsed time exceeds a predetermined value, processing so as to notify that effect. An imaging method characterized by the above. 9. A first white balance control for adjusting a white balance using an image pickup device for receiving a subject image light transmitted through a photographing lens and electronically picking up the image, and using an image signal obtained from the image pickup device. A first white balance detecting step of generating a signal, and a second white balance detecting step of generating a second white balance control signal for white balance adjustment using a signal obtained from a colorimetric sensor other than the image sensor. An image pickup method for an electronic still camera, comprising: a step, and a white balance adjustment step of determining a final white balance adjustment value based on a white balance control signal obtained from the two white balance detection steps, A second white balance control signal is set in advance by using the second white balance detection step, and the second white balance control signal is set. A measuring step of measuring the number of imaged frames from the time when the balance control signal is stored and set, and a notification step of processing to notify when the number of imaged frames measured in the measuring step is equal to or more than a predetermined number. An imaging method comprising: 10. A first white balance control for adjusting a white balance using an image pickup device for receiving a subject image light transmitted through a taking lens and electronically picking up the image, and using an image signal obtained from the image pickup device. A first white balance detecting step of generating a signal, and a second white balance detecting step of generating a second white balance control signal for white balance adjustment using a signal obtained from a colorimetric sensor other than the image sensor. An image pickup method for an electronic still camera, comprising: a step, and a white balance adjustment step of determining a final white balance adjustment value based on a white balance control signal obtained from the two white balance detection steps, A second white balance control signal is set in advance by using the second white balance detection step, and the second white balance control signal is set. A first measurement step of measuring the number of photographic frames from the time of setting and storing the white balance control signal, the second
When the measurement value measured in the second measurement step of measuring the elapsed time from the time of setting the white balance control signal of No. 1 and at least one of the measurement steps exceeds a predetermined value And a notification step of performing processing so as to notify that effect. 11. When the measured value measured in at least one of the measuring steps exceeds a predetermined value, the second white balance control signal stored in advance is used. The imaging method according to claim 9, further comprising a releasing step of releasing determining the final adjustment value of the white balance. 12. The measurement value measured in at least one measurement step of any one of the measurement steps is during continuous shooting, or during exposure blanketing for continuously exposing and shooting a plurality of frames while changing an exposure value. The imaging method according to claim 11, further comprising a prohibition step of prohibiting the operation of the releasing step when the predetermined value is exceeded. 13. A computer-readable storage medium having recorded thereon a program for causing a computer to function as each unit according to any one of claims 1 to 6. 14. A computer-readable storage medium having recorded thereon a program for causing a computer to execute the imaging method according to any one of claims 7 to 12. 15. A computer program that causes a computer to execute the imaging method according to claim 7. Description: