JP2000253409A - Imaging device, imaging method, and storage medium - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an imaging device, an imaging method, and a storage medium capable of obtaining an appropriate white balance when a strobe is used. SOLUTION: CCD which is an image pickup device during exposure
The brightness of the imaging surface 20 is measured by the dimming sensor 17,
When the measured value exceeds a predetermined value, it is determined that strobe light emission has been performed, and data relating to white balance is changed from data before exposure to data during exposure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image pickup apparatus such as a digital still camera, and more particularly to a white balance thereof.

[0002]

2. Description of the Related Art A conventional sequence for photographing a digital still camera is performed by a signal of SW1 (release half-press).
Performs F (auto focus), focuses on the subject, performs photometry, determines the aperture value and shutter speed, performs colorimetry with a colorimetric sensor, drives the shutter with the signal of SW2 (release full release), and controls the CCD, etc. The image pickup device is configured to perform exposure. In this configuration, photographing conditions of a subject shown in a viewfinder are determined before photographing, and photographing is performed. In a single-lens reflex camera type digital still camera, it is necessary to set exposure conditions and perform exposure before photographing. In addition, there is a digital still camera of a type in which feedback is provided from video signal data detected by an image pickup device such as a CCD to determine conditions at the time of photographing and perform photographing.

[0003]

In the case of the above-mentioned digital still camera, when the state at the time of photographing has changed from the state before photographing, for example, when a strobe is fired in synchronization with a release in a studio or the like, The white balance cannot be adjusted to the strobe light in the camera body unless the mode is set to the strobe light emission mode, and the processed image will deviate from an appropriate color balance. In the case of backlight compensation, if the external light is strong and the effect of the strobe is small even if the strobe light emission mode is set, or if the strobe does not reach, the color balance will be lost if the white balance is used for the strobe. .

The present invention has been made under such circumstances, and provides an image pickup apparatus, an image pickup method, and a storage medium capable of obtaining an appropriate white balance when a strobe is used. It is the purpose.

[0005]

In order to achieve the above object, according to the present invention, an imaging apparatus is configured as described in the following (1) to (6), and an imaging method is performed in the following (7) to (9). And the storage medium is configured as in the following (10).

(1) A strobe light emission judging means for judging the presence or absence of strobe light emission during photographing, and when the strobe light emission judging means judges the presence of strobe light emission, data on white balance is obtained from data before exposure based on data before exposure. An imaging device comprising: a control unit configured to perform control to change to data.

(2) The imaging apparatus according to (1), wherein predetermined data for strobe light is used as the data during exposure.

(3) The image pickup apparatus according to (1) or (2), wherein the data before exposure and the data during exposure are recorded in a header of image data.

(4) The image pickup apparatus according to any one of (1) to (3), further comprising a colorimetric sensor for measuring a color temperature of the subject, wherein the strobe light emission determining means is configured to determine whether or not the strobe light is emitted before and during the exposure. An image pickup apparatus for judging the presence or absence of strobe light emission based on a difference in measurement results of the colorimetric means.

(5) The image pickup apparatus according to any one of (1) to (3), further comprising a sensor for measuring the brightness of an image pickup surface of the image pickup device, wherein the strobe light emission determination means includes an output of the sensor. An image pickup apparatus for determining that strobe light is emitted based on a value exceeding a predetermined value.

(6) The image pickup apparatus according to any one of (1) to (3), further comprising a sensor for measuring the brightness of an image pickup surface of the image pickup device, wherein the strobe light emission determining means includes an output of the sensor. An image pickup apparatus for further differentiating a value obtained by integrating the above, and judging the presence of strobe light when the differentiated value exceeds a predetermined value.

(7) An image pickup method in an image pickup apparatus, wherein a step of judging whether or not strobe light is emitted and a step of judging whether or not strobe light is emitted in the step of judging strobe light emission, the white balance data is used as data before exposure. And a white balance data changing step of changing the data to data during exposure.

(8) An image pickup method for an image pickup apparatus, wherein a step of judging whether or not strobe light is emitted and a step of judging whether or not strobe light is emitted in the step of judging whether or not strobe light is emitted, the white balance data are used as data before exposure. A white balance data changing step of changing the data to predetermined data for strobe light emission.

(9) An image pickup method in an image pickup apparatus, wherein a step of judging whether or not to emit a flash light for judging the presence or absence of the light emission of the electronic flash, and a step of judging whether or not the light emission of the electronic flash is present in the step of judging the light emission of the electronic flash, the header of the image data includes A white balance data recording step of recording data relating to white balance during exposure.

(10) A storage medium storing a program for realizing the imaging method according to any one of (7) to (9).

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to embodiments of a digital still camera. In addition,
The present invention is not limited to the shape of an object such as a digital still camera,
The present invention can be similarly implemented in the form of a storage medium such as a CD-ROM in which an imaging method and a program for implementing the method are stored.

[0017]

FIG. 1 is a block diagram showing the configuration of a "digital still camera" according to a first embodiment. In the illustrated configuration, the light incident on the camera is the lens 1
a, 1b, the light amount is adjusted by the diaphragm 2, and the light passes through the lens 1c. Before shooting, the incident light is
The light is reflected by a, and the top and the left and right of the image are returned by the prism including the mirror 5 and the like, and the observer can check the subject through the eyepiece lens 7. A part of the light reflected by the mirror 4a passes through the mirror 5, is reflected by the mirror 6, and is captured by the photometric sensor 16. The light transmitted through the mirror 4a is reflected by the mirror 4b and is captured by the distance measuring sensor 14b. The distance measurement sensor 14b sends information of the focus of the subject to the camera operation control microcomputer 10, and the camera operation control microcomputer 10 sends the lens drive means 11 the drive direction and speed in order to drive the focus lens 1a. Send a signal.

Next, at the time of photographing, the microcomputer 10 for controlling the camera operation determines an aperture value based on the output signal of the photometric sensor 16 and sends a signal to the aperture driving means 12 to drive the aperture 2. Next, the microcomputer 10 sends a drive signal to the mirror driving means 14a to retract the finder mirror 4a and the AF mirror 4b in the middle of the shooting optical path from the shooting optical path. Further, the microcomputer 10 outputs a driving signal to the shutter driving means 13 to open the shutter 3. The imaging device such as the CCD 20 can expose the light incident from the lens 1 only while the shutter 3 is open. The microcomputer 10 also measures the brightness of the surface of the CCD 20 to measure and adjust the amount of light exposed to the CCD 20.
The light is measured by the light control sensor 17 based on the reflected light 20 and light is controlled. Also, the camera operation control microcomputer 10
If it is determined that the exposure amount is equal to or less than the appropriate range, a light emission signal is output to the strobe light emitting means 18 in order to make the strobe 8 emit light, and the integrated value of the output signal of the light control sensor 17 is used.
If it is determined that the exposure amount has reached an appropriate value, the shutter 3
And outputs a signal to the shutter driving means 13 to close the shutter.

The camera operation control microcomputer 10 includes:
In response to the signals from the switches SW1 and 9a, a shooting preparation operation is started, photometry and distance measurement are performed, and the focus lens 1a is driven in order to focus on the subject. The microcomputer 10
In response to the signal from the SW 2.9b, the camera enters a shooting operation, drives the aperture, retracts the mirror, opens the shutter, and performs exposure.

Next, the microcomputer 30 for image processing control outputs a signal for causing the timing generator 27 to output a timing signal for driving the CCD 20, and the driver 26 drives the CCD 20 to output the accumulated charges. . The output electric charge is taken into the correlated double sampling and auto gain control circuit 21 as a voltage value, and is converted from an analog signal to digital data by the A / D converter 21. The converted digital data is stored in the buffer memory 23 as a frame image. The image data stored in the buffer memory 23 is taken into the work memory 25 via the bus 33 of the image control microcomputer 30, and image processing is performed with the image memory 30. The image created in the work memory 25 is sent to the liquid crystal driver 29 and displayed on the liquid crystal display 28 for display. The image is sent to the external memory 24 via the bus 33 and recorded.

The image control microcomputer 30 communicates with the camera operation control microcomputer 10 via the cable 19 and receives information on the camera when the image was taken.
Information is added to the header as part of the image data. The colorimetric sensor 31 measures the color temperature at the time of shooting, and outputs a signal to the image control microcomputer 30 via the driver 32.

Next, the operation of the embodiment will be described with reference to the flowcharts of FIGS.

First, the operation of the camera operation control microcomputer 10 will be described with reference to the flowchart of FIG. #
In step 1, it is determined whether or not SW1 is turned on. This is repeated until it becomes On. When SW1 turns on, # 2
Then, the distance is measured, and the lens is driven so that the subject is in focus. Next, in step # 3, photometry is performed, and the aperture value and shutter speed for proper exposure are calculated and set. Next, in # 4, it is confirmed whether SW2 has been turned on. If it is not On, it is determined in # 5 whether a predetermined time has elapsed. If SW2 is not turned on after a lapse of a predetermined time, the process returns to the start, and waits for SW1 to be turned on. Also, S
If W2 is turned on within a predetermined time, the process proceeds to step # 6, where the aperture blades are stopped down to the aperture value set by photometry, and at step # 7, the mirror 4a for the finder and the mirror 4b for distance measurement are retracted from the optical axis. Then, in # 8, the shutter curtain is driven at the shutter speed set by the photometry so that the CCD 20 can expose light. At the same time, the brightness of the CCD surface is measured at # 9, and the change in the light amount is measured. In step # 10, the exposure is completed. If the change in the light amount exceeds a predetermined value, it is determined that the strobe light is emitted. Next, at step # 11, the aperture is opened, and at step # 12, the mirrors 4a, 4 retracted from the optical axis.
b is returned to the original position, and the shutter 3 is charged to the original position. In # 13, if the buffer memory 23 is Full
Otherwise, the next image can be fetched, so that the process returns to the start, and the image processing control microcomputer 30 transmits the information of the photographing data by the request of the image processing control microcomputer 30 until the switch SW1 turns on.

Next, the operation of the image processing control microcomputer 30 will be described with reference to the flowchart of FIG. Similarly to FIG. 2, it is confirmed that SW1 is turned on at # 21,
When 1 becomes On, unnecessary charges on the pixels of the CCD 20 are firstly swept out in step # 22, and the CCD 20 is cleared. Next, in # 23, colorimetry (measurement of the color temperature of the subject) is performed by the colorimetric sensor 31, and the white balance is determined.
Next, in # 24, it is confirmed that SW2 is turned on.
If SW2 does not become On for a predetermined time in # 25, S is executed again.
Wait for W1 to turn On. If SW2 is turned on within a predetermined time, the process returns to the start, and at # 26, the CCD2
The charge accumulation is started at 0, and the colorimetry is performed during accumulation at # 27. If the result of the color measurement is different from the data before the start of the accumulation even after the accumulation is completed in # 28, it is determined that the strobe has been turned on. Next, at step # 29, the CCD 20
The transfer of the electric charge stored in the memory is started. In step # 30, a request is sent to the camera operation control microcomputer 10 to transmit the photographing information, and the photographing information is received. At # 31, it is confirmed whether or not the buffer memory 23 is Full. If it is not Full, the process returns to the start and waits for SW1 to become On. If the buffer memory 23 is Full, it is not possible to take an image. At step # 33, the image data in the buffer memory 23 is subjected to image processing, and the camera operation control microcomputer 10
Is added to the information header obtained from the external memory 24 at # 34.
Transfer to When the transfer is completed in # 35, in # 36,
It is checked whether or not the buffer memory 23 is empty, and the image processing is repeated until the buffer memory 23 becomes empty. If the buffer memory 23 becomes empty, the process returns to the start and waits for SW1 to be turned on.

Further, in order to determine that the strobe light is emitted, as shown in FIG. 4A, the output of the light control sensor 17 is directly observed, and when the value exceeds a predetermined amount, the strobe light is emitted. You may judge that. Alternatively, when controlling the strobe light from the normal camera side, the output of the light control sensor 17 is integrated, and if the integrated value exceeds a predetermined amount, the strobe light emission is stopped as proper exposure.
As shown in (c), the integrated value of the output of the light control sensor 17 is differentiated again to return to the amount of change in the amount of light. If the value exceeds a predetermined value, it is determined that the strobe light is emitted. good.

Further, when it is determined that the strobe light is emitted, the colorimetry is performed again by the colorimetric sensor 31, and the white balance data in the header to be added to the image data is converted from the white balance data before the exposure to the white balance during the exposure. By rewriting the data, an appropriate white balance value can be obtained when the data is taken into a personal computer and subjected to image processing. Alternatively, when the white balance is set to auto, if it is determined that the strobe light has been emitted, an image having an appropriate color balance can be obtained by setting the white balance to a predetermined setting when the strobe is used. Become.

As described above, according to this embodiment,
The white balance is auto, the color temperature before exposure is measured, and from the change in the light amount during exposure and the change in color temperature before and during exposure, it is determined that the flash has fired, and the white balance data is collected. By rewriting the value before exposure to a value during exposure or a value for a predetermined flash emission, an appropriate white balance is obtained,
When performing image processing, the color balance is less likely to be lost.

(Embodiment 2) In the case of the embodiment 1, if it is determined that the strobe light is emitted, the white balance data when the strobe is used is rewritten. However, the white balance in a range where the strobe does not reach may not always be appropriate.
Therefore, in the present embodiment, as shown in FIG. 5, both the white balance data before exposure and the white balance data during exposure are added to the header of the image data for the white balance data that is rewritten in the first embodiment. To do it. Thus, when creating an image from data on a personal computer, an appropriate white balance can be selected. Thus, even in the case of strobe light emission, it is possible to select a white balance in an area where light emission does not reach.

As described above, according to the present embodiment,
By recording both the white balance data before exposure and the white balance data during exposure in the header file, it is possible to select the white balance of the area where the flash does not reach even if the flash fired, When a user creates an image, an appropriate white balance can be obtained.

[0030]

As described above, according to the present invention,
When a strobe is used, an appropriate white balance can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a first embodiment.

FIG. 2 is a flowchart showing the operation of a camera operation control microcomputer;

FIG. 3 is a flowchart showing the operation of an image processing control microcomputer;

FIG. 4 is an explanatory diagram of a method of determining strobe light emission from a change in light amount.

FIG. 5 is an explanatory diagram of a second embodiment.

[Explanation of symbols]

 10 Microcomputer for controlling camera operation 17 Dimming sensor 30 Microcomputer for controlling image processing

Continued on the front page F term (reference) 5C065 AA03 BB02 BB07 BB08 BB11 BB41 BB48 CC01 DD02 EE01 EE02 EE12 EE18 FF02 FF03 GG12 GG18 GG24 GG30 5C066 AA01 CA13 DD07 EA04 EA15 FA02 GA01 GB01 KE19 KM05

Claims (10)

[Claims] 1. A flash emission determining means for determining the presence or absence of flash emission during photographing, and when the flash emission determination means determines the presence of flash emission, data on white balance is converted from data before exposure to data being exposed. Control means for controlling the image pickup apparatus to change to an image pickup apparatus. 2. An imaging apparatus according to claim 1, wherein predetermined data for strobe light is used as the data during exposure. 3. The imaging apparatus according to claim 1, wherein the data before the exposure and the data during the exposure are recorded in a header of the image data. 4. The image pickup apparatus according to claim 1, further comprising a colorimetric sensor for measuring a color temperature of a subject, wherein the strobe light emission determination unit performs the measurement before and during the exposure. An imaging apparatus for determining the presence or absence of strobe light emission based on a difference in measurement results of color means. 5. The image pickup apparatus according to claim 1, further comprising a sensor for measuring the brightness of an image pickup surface of the image pickup device, wherein the strobe light emission judging means determines that an output of the sensor is a predetermined value. An image pickup apparatus, which determines that strobe light is emitted when a value is exceeded. 6. The imaging device according to claim 1, further comprising a sensor for measuring the brightness of an imaging surface of the imaging device, wherein the strobe light emission determination unit integrates an output of the sensor. An imaging device for further differentiating the calculated value, and determining that strobe light is emitted when the differentiated value exceeds a predetermined value. 7. An image pickup method for an image pickup apparatus, comprising: a strobe light emission determining step for determining whether or not strobe light is emitted; and determining whether or not strobe light is emitted in the strobe light emission determination step, the white balance data is determined from data before exposure. A white balance data changing step of changing to data during exposure. 8. An image pickup method for an image pickup apparatus, comprising: a strobe light emission judging step for judging the presence / absence of strobe light emission; and when the strobe light emission is judged in the strobe light emission judgment step, white balance data is calculated from data before exposure. A white balance data changing step of changing to data for strobe light emission determined in advance. 9. An image pickup method for an image pickup apparatus, comprising: a strobe light emission determination step for determining whether or not strobe light is emitted; A white balance data recording step of recording data relating to the inside white balance. 10. A storage medium storing a program for realizing the imaging method according to claim 7. Description: