JP2013255073A - Imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging apparatus which, even when an exposure time in pre-light-emission photometry is shortened, is capable of performing accurate light control.SOLUTION: In the pre-light-emission photometry, a CPU 21 controls an imaging control unit 22 to cause an imaging device 15 to image plural frames. With overlapping timing of the exposure periods of the respective frames between imaging of the frames, the CPU 21 controls a flash control unit 26 to cause a flash light-emission unit 27 to perform pre-light-emission. Thereafter, the CPU 21 calculates the light emission amount of the flash light-emission unit 27 in main exposure on the basis of the image data obtained by imaging the frames.

Description

  The present invention relates to an imaging apparatus having a flash light control function.

  Conventionally, photographing using a flash device is sometimes performed in a scene with low light quantity such as at night or indoors or in a backlight scene to compensate for the shortage of light quantity. In photographing using this flash device, it is necessary to appropriately control the light emission amount of the flash device so that the exposure amount of an image obtained after flash photographing becomes an appropriate exposure amount. This control of the amount of emitted light is generally called dimming control.

  A dimming control using pre-emission (hereinafter, this control is referred to as pre-emission control) is known as a technique often used in dimming control. Pre-flash control acquires the steady light data obtained from the image sensor with the flash device not emitting light and the pre-flash data obtained from the image sensor with the flash device emitting light with a small amount of light before the main exposure. This is a method of determining the light emission amount of the flash device during the main exposure using the steady light data and the pre-light emission data. Such pre-emission control is disclosed in Patent Document 1, for example.

  In recent years, a CMOS image sensor (hereinafter simply referred to as a CMOS sensor) may be used as an image sensor used in a digital camera. The CMOS sensor is configured by two-dimensionally arranging pixels including photoelectric conversion elements. As the electronic shutter system of the CMOS sensor, a global shutter system and a rolling shutter system are known. The global shutter method is a method in which charges accumulated in pixels are read all at once for each frame. On the other hand, the rolling shutter method is a method of reading out charges accumulated in pixels in units of lines. For example, Patent Document 2 proposes a rolling shutter type imaging apparatus. In the case of a rolling shutter type imaging apparatus such as Patent Document 2, the exposure start and end timings are shifted for each line.

JP 2006-053493 A JP 2007-228047 A

  Here, in the rolling shutter type imaging apparatus, in order to irradiate flash light to all of the light control areas, for example, it is conceivable to increase the exposure time. However, if the exposure time is lengthened, the influence of stationary light in the image data obtained during pre-emission becomes large. Conversely, it may be possible to shorten the exposure time and perform dimming control only on the part irradiated with flash light. In this case, however, the accuracy of dimming control is higher than when the entire surface is irradiated with flash light. Will fall. Further, it is possible to irradiate the entire surface of the light control area with the flash light by causing the flash light to emit light for a certain period without using the flash light as instantaneous light. However, in this case, energy is required to keep the flash light continuously emitted for a certain period.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an imaging apparatus capable of performing dimming control with high accuracy even if the exposure time during pre-emission photometry is shortened. .

  In order to achieve the above object, an imaging apparatus according to an aspect of the present invention includes an imaging unit that captures an image of a subject to obtain image data relating to the subject, and a flash light emitting unit that emits flash light to the subject. An imaging control unit that executes imaging of a plurality of frames by the imaging unit, a flash control unit that pre-flashes the flash light emitting unit at a timing when the exposure periods of the respective frames overlap, and preflashed the flash light emitting unit As a result, the image processing apparatus includes a control unit that calculates a light emission amount of the flash light emitting unit during main exposure of the image capturing unit based on a plurality of frames of image data obtained by the image capturing unit.

  According to the present invention, it is possible to provide an imaging apparatus capable of performing dimming control with high accuracy even when the exposure time during pre-emission photometry is shortened.

1 is a block diagram illustrating a configuration of an imaging device having a light control function according to an embodiment of the present invention. 3 is a flowchart illustrating a flash photographing operation of the imaging apparatus. It is a flowchart shown about the detail of flash light emission control processing. It is a timing chart which shows the outline | summary of 2 frame light emission. It is a figure which shows the 1st example of the imaging | photography scene which performs 2 frame light emission. It is a figure which shows the 2nd example of the imaging | photography scene which performs 2 frame light emission.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of an imaging apparatus having a light control function according to an embodiment of the present invention.

  1 includes a lens frame 11, an image sensor 15, an analog / digital (A / D) conversion unit 16, an SDRAM 17, a CPU 21, an imaging control unit 22, a lens frame control unit 23, AE control unit 24, AF control unit 25, flash control unit 26, flash light emitting unit 27, power supply control unit 28, power supply circuit 29, image processing unit 31, nonvolatile memory 32, and built-in memory 33 An external memory 34, a display unit 35, and an operation unit 36.

  The lens frame 11 has a photographic lens 12 and a diaphragm 13 therein. The photographing lens 12 is an optical system having a plurality of lenses such as a focus lens and a zoom lens, and condenses an optical image of a subject on the image sensor 15. Each lens constituting the photographic lens 12 is moved in the optical axis direction by a lens frame control unit 23 that operates in accordance with an instruction from the CPU 21. The diaphragm 13 adjusts the amount of light incident on the image sensor 15 via the photographing lens 12. The aperture 13 is opened and closed by a lens frame control unit 23 that operates in accordance with an instruction from the CPU 21.

  The imaging element 15 has an imaging area in which pixels having photoelectric conversion elements (such as photodiodes) are two-dimensionally arranged. In this imaging area, for example, a Bayer color filter is formed. The image sensor 15 converts the amount of light into a charge amount by receiving and photoelectrically converting the light collected by the photographing lens 12 into each pixel, and further converting the charge into an analog voltage signal (image signal). Output to the A / D converter 16. The image sensor 15 of the example of this embodiment is a CMOS sensor. The exposure time of the image sensor 15 is controlled by a rolling shutter method.

  The A / D converter 16 converts the analog image signal output from the image sensor 15 into a digital image signal (hereinafter referred to as image data).

  The SDRAM 17 is a storage unit that temporarily stores various data such as image data obtained by the A / D conversion unit 16 and image data processed by the image processing unit 31.

  CPU21 controls each block of the imaging device shown in FIG. In the AE control, the CPU 21 controls the imaging control unit 22 and the lens frame control unit 23 according to the exposure amount calculated by the AE control unit 24. In addition, the CPU 21 controls the imaging control unit 22 according to the focus evaluation value calculated by the AF control unit 25 during the AF control. The CPU 21 also functions as a control unit that determines the light emission amount and the light emission timing of the flash light emitting unit when the flash light emitting unit 27 needs to emit light. Furthermore, the CPU 21 controls the display unit 35 and also controls when image data is recorded in the internal memory 33 or the external memory 34.

  The imaging control unit 22 controls the operation of the imaging element 15 according to an instruction from the CPU 21. In response to an instruction from the CPU 21, the imaging control unit 22 sets the frame rate of the imaging device 15, and inputs the vertical synchronization signal VD and the horizontal synchronization signal HD to the imaging device 15 according to the set frame rate. The operation of the element 15 is controlled. The image sensor 15 performs imaging for one frame in synchronization with the vertical synchronization signal VD. At this time, the image sensor 15 sequentially performs exposure (signal accumulation) line by line in synchronization with the horizontal synchronization signal HD.

  The lens frame control unit 23 controls the operation of the photographing lens 12 and the diaphragm 13 in the lens frame 11 in accordance with an instruction from the CPU 21. The lens frame control unit 23 drives each lens in the optical axis direction in accordance with an instruction from the CPU 21 and controls the aperture amount of the diaphragm 13.

  The AE control unit 24 calculates the exposure amount (aperture value and exposure time) of the image sensor 15 for automatic exposure control (AE). The calculation of the exposure amount is performed using, for example, subject brightness (brightness of a shooting scene including the subject) obtained from image data obtained via the image sensor 15. The data for calculating the subject brightness may be the output of a dedicated photometric sensor.

  The AF control unit 25 performs processing for automatic focus control (AF). For example, the AF control unit 25 extracts high-frequency component data from the image data obtained via the image sensor 15 and integrates the high-frequency component data for each predetermined area to obtain a focus evaluation value. Note that the AF control unit 25 may be configured to include a dedicated sensor so that the defocus amount of the photographic lens 12 can be obtained.

  The flash control unit 26 causes the flash light emitting unit 27 to emit light in response to an instruction from the CPU 21. Although the detailed description will be given later, the flash control unit 26 also performs control for causing the flash light emitting unit 27 to emit light once during the exposure period of two frames.

  The flash light emitting unit 27 includes a light emitting tube such as a xenon (Xe) tube and a reflector, and emits light when receiving a light emission instruction from the flash control unit 26.

  The power supply control unit 28 controls the power supply circuit 29 such as detecting the remaining amount of a battery as a drive power supply for the power supply circuit 29.

  The power supply circuit 29 includes a battery as a drive power supply and a booster circuit that boosts the voltage of the battery to a voltage having a magnitude required by each block of the imaging apparatus, and supplies power to each block of the imaging apparatus.

  The image processing unit 31 performs various image processes on the image data. This image processing includes, for example, white balance correction processing, synchronization processing, color conversion processing, and gamma correction processing. The image processing unit 31 also compresses an image for recording, decompresses the compressed image, and the like.

  The nonvolatile memory 32 stores various parameters necessary for the operation of the imaging device. The nonvolatile memory 32 also stores a program executed by the CPU 21. The CPU 21 reads parameters necessary for various sequences from the nonvolatile memory 32 according to a program stored in the nonvolatile memory 32 and executes each process.

  The built-in memory 33 and the external memory 34 are recording media for recording various data such as image data compressed by the image processing unit 31. The built-in memory 33 is a recording medium built in the imaging apparatus, and the external memory 34 is a recording medium that is detachable from the imaging apparatus.

  The display unit 35 is, for example, a liquid crystal display, and displays various images such as an image based on the image data processed by the image processing unit 31 and a menu screen.

  The operation unit 36 is an operation member such as a power button, a release button, and a selection key. When any one of the operation members of the operation unit 36 is operated by the user, the CPU 21 executes each process according to the user's operation. The power button is an operation member for instructing the power on / off of the imaging apparatus. The release button is an operation member for instructing execution of a photographing operation. This release button has a 1st release switch and a 2nd release switch. When the release button is pressed halfway and the 1st release switch is turned on, the CPU 21 performs a shooting preparation sequence such as AE control and AF control. When the release button is fully pressed and the 2nd release switch is turned on, the CPU 21 performs a photographing operation (main exposure). The selection key is an operation member for performing various settings of the imaging apparatus.

  Next, the flash photographing operation of the imaging device will be described. The flash photographing operation is performed when the brightness of the subject is darker than a predetermined level or when the user sets the flash light emitting unit 27 to emit light. Note that the image pickup apparatus shown in FIG. 1 can also perform shooting without the flash emission unit 27 emitting light. However, since the photographing operation without light emission of the flash light emitting unit 27 is the same as the conventional one, the description thereof is omitted here.

  FIG. 2 is a flowchart showing the flash photographing operation of the imaging apparatus. Here, the processing of FIG. 2 is controlled by the CPU 21. In the flowchart of FIG. 2, the illustration of the through image display, AE control, AF control, and the like before the flash photographing operation is omitted.

  The CPU 21 determines whether the release button is fully pressed by the user and the 2nd release switch is turned on (step S101). In step S101, the CPU 21 repeats the determination in step S101 until the 2nd release switch is turned on.

If it is determined in step S101 that the 2nd release switch has been turned on, the CPU 21 performs steady light metering (step S102). In this process, CPU 21, while controlling the image pickup control unit 22 in accordance with a predetermined exposure time T _E, performs ambient light exposure operation so as not to emit the flash light emitting unit 27. The exposure time _TE is a time at which the influence of stationary light is considered to be sufficiently small, and is recorded as a fixed value in the nonvolatile memory 32, for example. Incidentally, it may be variable depending on the shooting conditions the exposure time T _E. For example, if a small influence of ambient light can be made longer exposure time T _E. After the steady light exposure operation, the CPU 21 inputs evaluation value data obtained by the steady light exposure operation to the flash control unit 26. The flash controller 26 causes the SDRAM 17 to store subject luminance data calculated from the evaluation value data obtained by the steady light exposure operation as the steady light data.

  After steady light metering, the CPU 21 performs flash emission control for pre-emission (step S103). Although detailed description will be described later, in the flash emission control for pre-emission, the light emission amount and the emission timing of the flash emission unit 27 at the time of pre-emission in step S104 are determined.

  After the flash emission control, the CPU 21 executes pre-emission photometry (step S104). In this process, the CPU 21 controls the imaging controller 22 in accordance with the exposure time determined in the flash emission control, and controls the flash controller 26 in accordance with the emission amount and the emission timing determined in step S103, thereby controlling the flash emission unit 27. A pre-flash exposure operation for emitting light is performed. Then, the CPU 21 inputs evaluation value data obtained by the pre-flash exposure operation to the flash control unit 26. The flash controller 26 causes the SDRAM 17 to store the subject luminance data calculated from the evaluation value data obtained by the pre-flash exposure operation as pre-flash data.

  After the pre-flash metering, the CPU 21 performs flash emission control for main flash (step S105). Although detailed description will be given later, in the flash emission control for main light emission, the light emission amount and the light emission timing of the flash light emission unit 27 at the time of the main exposure in step S106 are determined.

  After the flash emission control, the CPU 21 performs the main exposure (step S106). In this process, the CPU 21 controls the lens barrel control unit 23 and the imaging control unit 22 according to the exposure amount calculated in the AE control executed in advance, and the flash light emitting unit according to the light emission amount and the light emission timing determined in step S105. The main exposure operation for emitting light 27 is performed. Then, the CPU 21 inputs the image data obtained by the main exposure operation to the image processing unit 31. The image processing unit 31 performs image processing on the image data obtained by the main exposure operation. After the image processing, the CPU 21 records the compressed image data obtained as a result of the image processing in the built-in memory 33 or the external memory 34 as an image file. Thereafter, the CPU 21 ends the process of FIG.

FIG. 3 is a flowchart showing details of the flash emission control process.
The CPU 21 determines whether the current process is a flash emission control process at the time of pre-emission (step S201).

In step S201, if the current process is judged as a flash light emission control process at the pre-emission, CPU 21, the exposure time T _E is determined whether there are signals read time T _R or of the image sensor 15 (step S202). Here, the signal read time T _R, in the imaging area of the imaging element 15, a time required for reading image signals from the necessary area dimming (referred light adjustment area), such as fixed as a fixed value This is information recorded in the memory 32. Depending on the operation mode of the image sensor 15, thinning readout may be performed. When the skip reading is to shorten the signal read time T _R in accordance with the thinning number.

In step S202, the exposure time T _E is not the signal read time T _R above, that is, when it is determined that it is impossible to irradiate the flash light dimming area in one emission, CPU 21 has the current shooting scene 2 It is determined whether or not the frame emission condition is satisfied (step S203). The two-frame emission condition is a condition for determining whether to emit pre-flash light once for two frames. When dimming is required for a wide dimming area, it is determined that the two-frame emission condition is satisfied. A photographic scene that requires dimming control over a wide range of dimming areas is a photographic scene in which a plurality of subjects exist at a distance where flash light reaches, for example. In such a shooting scene that satisfies the two-frame emission condition, for example, whether wrinkles are detected from the image data (whether there is a person), whether there are a predetermined number (for example, two) or more of low-luminance areas, etc. It can be determined from. Of course, the user may be allowed to instruct execution of two-frame light emission.

  If it is determined in step S203 that the current shooting scene satisfies the two-frame emission condition, the CPU 21 determines the exposure condition for the second frame (step S204). Thereafter, after determining the exposure condition for the second frame in step S204, the CPU 21 sets the flash controller 26 to emit two frames at the next light emission (step S205).

  FIG. 4 is a timing chart showing an outline of two-frame light emission. In the two-frame light emission, the CPU 21 controls the image pickup control unit 22 to pick up two frames by the image pickup device 15. Then, the CPU 21 controls the flash control unit 26 to cause the flash light emitting unit 27 to pre-emit during the period during which the flash light is irradiated on the light control area. FIG. 4 shows an example in which the entire area of the imaging area is a dimming area. However, it is not always necessary that the entire imaging area is a light control area.

When the exposure time of the image sensor 15 is controlled by the rolling shutter system, in order to make the exposure time equal for each line, as shown in FIG. 4, the exposure start of each line is started by the signal readout time of each line. It is necessary to shift the exposure end timing. When the exposure of each line is controlled in this way, there is a possibility that the flash light is not irradiated to a part of the dimming area when the exposure time _TE is shortened. In this embodiment, by performing exposure for two frames, the exposure time for each frame is shortened, and a period during which flash light is applied to a wide range of light control areas is secured.

  As an example of a shooting scene that emits two frames, consider a scene 200 shown in FIG. 5A in which a person in backlight is shot with a copper image as a background subject. In the backlit state, the flash light emitting unit 27 is caused to emit light in order to properly expose the person. However, in this case, the exposure of the person can be made appropriate by the light emission of the flash light emitting unit 27, but the brightness of the copper image is also increased by the light emission of the flash light emitting unit 27, and the portion of the copper image can be blown out white. There is sex. In the shooting scene as shown in FIG. 5A, the exposure of the copper image as the background subject is also important as the exposure of the person as the main subject. Therefore, in a shooting scene such as that shown in FIG. 5A, it is desirable to perform light control over a wide range of light control areas so that the copper image portion does not fly out.

  When the two-frame light emission shown in FIG. 4 is performed on the shooting scene as shown in FIG. 5A, flash light is irradiated to the lower half area of the light control area shown in FIG. 5B in the first frame. In the second frame, image data 202 is obtained in a state in which the upper half area of the light control area shown in FIG. 5B is irradiated with flash light. Therefore, the image data 203 obtained by combining the upper half of the image data of the first frame and the lower half of the image data of the second frame is an image equivalent to the case where the flash light is irradiated on substantially the entire imaging area. It becomes data. Note that this image data synthesis is performed in, for example, the image processing unit 31.

  By performing dimming processing using such image data 203, the flash light emission unit 27 emits light so that the exposure of the person who is the main subject is appropriate and the portion of the copper image that is the background subject is not overexposed. can do. For example, by reducing the gain of the image signal output from the image sensor 15 or appropriately controlling the exposure time of the aperture 13 and the image sensor 15 during the main exposure, the portion of the copper image is overexposed by flash light irradiation. It is possible not to let it.

  As another example of a shooting scene that emits two frames, consider a scene in which an imaging device is vertically held and a plurality of people in backlighting are shot as shown in FIG. For example, when the imaging apparatus is vertically held as shown in FIG. 6, the right part of the scene is imaged above the imaging area, and the left part of the scene is imaged below the imaging area. Even in such a case, the flash light can be irradiated only to any one of a plurality of persons in the normal single light emission.

  When the two-frame light emission shown in FIG. 4 is performed on the shooting scene as shown in FIG. 6, the first frame flashes in the lower half (corresponding to the right half of the scene) of the dimming area shown in FIG. Image data 301 in a state where light is irradiated is obtained, and in the second frame, the upper half of the light control area (corresponding to the left half of the scene) shown in FIG. Image data 302 is obtained. Accordingly, the image data 303 obtained by combining the upper half of the image data of the first frame and the lower half of the image data of the second frame is an image equivalent to the case where flash light is irradiated on substantially the entire imaging area. It becomes data. By performing dimming using such image data 303, it is possible to make each person's exposure appropriate by the light emission of the flash light emitting unit 27.

Here, in the case of two-frame light emission in the present embodiment, the exposure time can be made different between the first frame and the second frame. For example, in FIG. 4, the exposure time of the first frame is a predetermined exposure time T _E (T _E = VD / 2 in the example of FIG. 4), and the exposure time of the second frame is the signal readout time T _R. It is said. The period of the vertical synchronization signal VD is a time corresponding to the exposure time determined by the AE control or the frame rate at the time of live view display. In the example of FIG. 4, the exposure start timing of the second frame is synchronized with VD by delaying the exposure start of the first frame by VD / 2 (= T _E ). The process of determining the exposure start timing and the exposure time is the process of step S204. For example, when determining the timing of the exposure time and the exposure start of each frame as shown in FIG. 4, in the first frame, the exposure time by a T _E, to reduce the influence of ambient light It is possible. On the other hand, the second frame is overexposed, but the amount of light emission can be calculated using information for one frame.

  Returning to the description of FIG. When determining in step S201 that the current process is not the flash emission control process at the time of pre-emission, the CPU 21 shifts the process to step S207.

Further, in step S202, if the exposure time T _E is the signal read time T _R above, namely it is determined that can be irradiated with flash light in the entire range of the dimming area in one emission, or in step S203, 2 frames If it is determined that the light emission condition is not satisfied, the CPU 21 sets the flash control unit 26 to emit light once at the next light emission (step S206).

  After steps S201, S205, and S206, the CPU 21 calculates the next light emission amount of the flash light emitting unit 27 (step S207). When the process proceeds to step S207 via step S205 or step S206, the CPU 21 calculates the light emission amount at the time of pre-light emission. That is, the CPU 21 calculates the light emission amount of the flash light emission unit 27 at the time of pre-emission photometry according to the result of the steady light metering in step S106, and sets the calculated light emission amount in the flash control unit 26. In addition, when the process of step S207 is performed through step S201, the CPU 21 calculates the light emission amount during the main light emission. In other words, the CPU 21 calculates the light emission amount of the flash light emission unit 27 according to the result of the pre-light measurement in step S108, and sets the calculated light emission amount in the flash control unit 26.

  After calculating the light emission amount, the CPU 21 determines the next light emission timing of the flash light emitting unit 27 (step S208). Thereafter, the CPU 21 ends the process of FIG.

In the case of pre-emission with one emission, the CPU 21 determines the next timing of the flash emission unit 27 so that flash light is emitted in the entire range of the light control area during the pre-emission exposure period.
In the case of two-frame pre-emission, the CPU 21 emits flash light during a period in which the exposure period of a necessary line in the dimming area overlaps between the exposure period of the first frame and the exposure period of the second frame. Thus, the next timing of the flash light emitting unit 27 is determined. In FIG. 4, the end timing of exposure of the center line of the light control area is the flash light emission timing, but it is sufficient that the exposure periods of the necessary lines in the light control area overlap. It is not necessary to synchronize the end of exposure and the light emission timing.
In the case of the main light emission, the next timing of the flash light emission unit 27 is determined so that the subject whose exposure is appropriate is irradiated with the flash light.

  As described above, according to this embodiment, even if the exposure time is shortened by performing imaging of a plurality of frames, the exposure periods of necessary lines (for example, all lines) in the light control area can be overlapped. Is possible. As a result, even if the exposure time for each frame is shortened to reduce the influence of steady light, the light control accuracy can be improved.

Although the present invention has been described based on the above embodiment, the present invention is not limited to the above-described embodiment, and various modifications and applications are naturally possible within the scope of the gist of the present invention. For example, in the example of FIG. 4, the exposure period in the second frame imaging is set longer than the exposure period in the one frame imaging, but conversely the exposure period in the first frame imaging is set to the exposure period in the two frame imaging. It may be longer. Further, the exposure times of the first frame and the second frame may be made equal.
In the example of FIG. 4, two frames are imaged, but exposure of three frames or more may be performed.
Further, in the above-described embodiment, the light emission amount of the flash light emitting unit 27 during the main light emission is determined using the result of the pre-light measurement. In addition to this, the exposure of each part of the image is varied according to the subject brightness measured using the pre-flash photometry result, or the dynamic range of the image is expanded by using image composition by shooting multiple images to improve color reproduction. Image processing may be performed.

  Further, in the description of each operation flowchart described above, the operation is described using “first”, “next”, and the like for convenience, but this does not mean that it is essential to perform the operations in this order. Absent.

  Further, the above-described embodiments include various stages of the invention, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some configuration requirements are deleted from all the configuration requirements shown in the embodiment, the above-described problem can be solved, and this configuration requirement is deleted when the above-described effects can be obtained. The configuration can also be extracted as an invention.

  DESCRIPTION OF SYMBOLS 11 ... Mirror frame, 12 ... Shooting lens, 13 ... Aperture, 15 ... Imaging element, 16 ... Analog / digital (A / D) conversion part, 17 ... SDRAM, 21 ... CPU, 22 ... Imaging control part, 23 ... Mirror frame Control unit, 24 ... AE control unit, 25 ... AF control unit, 26 ... Flash control unit, 27 ... Flash light emission unit, 28 ... Power supply control unit, 29 ... Power supply circuit, 31 ... Image processing unit, 32 ... Non-volatile memory, 33 ... Built-in memory, 34 ... External memory, 35 ... Display unit, 36 ... Operation unit

Claims (4)

An imaging unit that captures an image of the subject to obtain image data relating to the subject;
A flash light emitting unit that emits flash light to the subject;
An imaging control unit that executes imaging of a plurality of frames by the imaging unit;
A flash control unit that pre-flashes the flash light emitting unit at a timing at which the exposure periods of the respective frames overlap;
As a result of pre-flashing the flash light emitting unit, a control unit that calculates a light emission amount of the flash light emitting unit at the time of main exposure of the imaging unit based on image data of a plurality of frames obtained by the imaging unit;
An imaging apparatus comprising:   The imaging apparatus according to claim 1, wherein the imaging control unit varies an exposure period of imaging of the plurality of frames.   The said control part synthesize | combines the image data of the said several frames, and calculates the light emission amount of the said flash light emission part at the time of the main exposure of the said imaging part based on the synthesized image data obtained by this synthesis | combination. Item 3. The imaging device according to Item 1 or 2.   The imaging apparatus according to claim 1, wherein the imaging unit includes a rolling shutter type imaging device.

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