JP2018148388A - Imaging apparatus and control method therefor - Google Patents

Abstract

An object of the present invention is to shorten the release time lag when acquiring a still image accompanied by strobe emission while acquiring a moving image, and to prevent the occurrence of missing frames in the moving image. In a first row and a second row different from the first row, an imaging element capable of independently controlling a readout cycle, and a first control for controlling light emission of a light emitting means. and a second control means for setting the accumulation times of the first row and the second row of the imaging device, the first control means causing the light emitting means to emit light and stopping at the second row. When capturing an image of a subject for an image, the light emitting means is caused to emit light according to the period from the end of the accumulation for the moving image in the first row or the timing of the still image photographing instruction to the start of the accumulation for the next moving image. The second control means is characterized in that the storage for the still image in the second row is performed during a period at least partially overlapping with the period during which the light emitting means is caused to emit light. [Selection drawing] Fig. 4

Description

  The present invention relates to an imaging apparatus capable of acquiring a still image while acquiring a moving image, and a control method and program thereof.

  2. Description of the Related Art Conventionally, an imaging apparatus that can acquire a still image while acquiring a moving image is generally known. In such an imaging device, if a light emitting device such as a strobe is caused to emit light when a still image is acquired, the influence of the light emission may affect the acquired moving image.

  Patent Document 1 describes an electronic camera in which a moving image recording frame and a still image recording frame are alternately provided in one image sensor. In the case of acquiring a still image by emitting a strobe, strobe emission is described in a still image recording frame. Further, Patent Document 2 describes an electronic camera that can independently read a moving image row and a still image row in one image sensor. Then, when shooting a still image by firing the strobe, the strobe is fired and the still image is accumulated in the period from the end of the accumulation of the movie in the first row to the beginning of the accumulation of the next movie. Is described.

JP 2004-64467 A Japanese Patent Application No. 2013-269681

  However, in the electronic camera of Patent Document 1, since a moving image frame and a still image frame are alternately provided in one image sensor, the accumulation time of the still image is limited by the frame rate of the moving image. May end up. In addition, since the electronic camera disclosed in Patent Document 2 performs pre-flash and main flash sequentially in different frames after an instruction to shoot a still image, a release time lag occurs.

  Accordingly, an object of the present invention is to shorten the release time lag when acquiring a moving image while acquiring a still image with strobe light emission, and to suppress missing frames in the moving image.

  To achieve the above object, the present invention has a plurality of imaging pixels arranged in a row direction and a column direction, and the first row and the second row different from the first row A charge storage type image sensor capable of independently controlling the readout cycle, a first control means for controlling the light emission of the light emitting means for illuminating the subject, and the image sensor according to the set shutter speed. A second control means for setting an accumulation time of the first row and the second row, wherein the first control means causes the light-emitting means to emit light and for the still image in the second row. When shooting a subject, the light emitting means emits light according to the period from the end of the moving image accumulation in the first row or from the timing of the still image shooting instruction to the start of the next moving image accumulation. The second control means at least partially overlaps the period of light emission of the light emitting means. In that period, characterized by causing the accumulation of a still image in the second row.

  According to the present invention, it is possible to provide an imaging apparatus capable of shortening the release time lag when acquiring a still image with strobe light emission while acquiring a moving image and preventing occurrence of missing frames in the moving image.

1 is a diagram illustrating a digital camera 100 that is a first embodiment of an imaging apparatus embodying the present invention. FIG. 1 is a block diagram illustrating an internal configuration of a digital camera 100 that is a first embodiment of an imaging apparatus embodying the present invention. 4 is a flowchart for describing moving image acquisition processing of the digital camera 100 which is the first embodiment of the imaging apparatus embodying the present invention. 6 is a timing chart for explaining the light emission timing of the strobe 217 and the accumulation timing of the image sensor 204 of the digital camera 100 which is the first embodiment of the imaging apparatus embodying the present invention.

[Example 1]
A digital camera (hereinafter simply referred to as a camera) 100 as an imaging apparatus as a first embodiment according to the present invention will be described with reference to FIGS. FIG. 1 is a diagram illustrating a camera 100 that is a first embodiment of an imaging apparatus embodying the present invention, and shows a rear view of the camera 100. FIG. Hereinafter, each part described in FIG. 1 will be described.

A display unit 101 that displays images and various information is provided on the back of the camera 100.
The display unit 101 is, for example, a liquid crystal display or an organic EL display, and may function as an operation unit by providing an input function as a touch panel. Further, an operation unit 105 including operation members such as various switches and buttons for receiving various operations by the user is provided on the back surface of the camera 100. In addition, on the back surface of the camera 100, a mode change switch 104 that switches a photographing mode for a subject and a controller wheel 102 that can be rotated are provided.

  Details of functions of the operation unit 105, the controller wheel 102, and the mode switch 104 will be described later with reference to FIG. On the upper surface of the camera 100, a shutter button 103 for giving a shooting instruction is provided. Details of the function of the shutter button 103 will be described later with reference to FIG.

  A recording medium slot (not shown) that can be opened and closed by a lid is provided on the lower surface of the camera 100, and a recording medium 130 such as a memory card can be inserted into and removed from the recording medium slot. . The recording medium 130 stored in the recording medium slot can communicate with a CPU 210 described later with reference to FIG. The recording medium 130 is not limited to a memory card that can be inserted into and removed from the recording medium slot, and may be an optical disk such as a DVD-RW disk or a magnetic disk such as a hard disk. Further, it may be built in the camera 100.

  FIG. 2 is a block diagram illustrating the internal configuration of the camera 100 that is the first embodiment of the imaging apparatus embodying the present invention. Hereinafter, the internal configuration of the camera 100 will be described with reference to FIG. The camera 100 includes a photographic lens 201 and a shutter 202 that constitute an imaging optical system, an imaging unit 203, and a strobe 217. The photographing lens 201 is a lens group including a zoom lens and a focus lens. The shutter 202 has a diaphragm function and adjusts the amount of light incident on the image sensor 204. The imaging unit 203 includes an imaging element 204 that converts an optical image into an electrical signal (analog electrical signal). The image sensor 204 is a charge storage type image pickup unit made of a solid-state image sensor such as a CCD or CMOS capable of generating an image by accumulating charges.

  The imaging unit 203 is provided with an AFE (Analog Front End), and the AFE adjusts the amount of gain for the analog electric signal (analog image data) output from the imaging element 204, performs sampling, and the like. Note that the AFE performs adjustments related to amplification and reduction of the gain amount for the acquired image data in accordance with an instruction from the CPU 210 described later. The imaging unit 203 has an A / D conversion unit 205. The A / D conversion unit 205 converts analog image data output from the image sensor 204 and whose gain amount is adjusted into a digital signal (digital image data).

  In the present embodiment, based on the image data obtained by the imaging unit 203, a photometric calculation unit 218 of the CPU 210 described later calculates the luminance value of the subject. This point will be described later. The camera 100 includes an image processing unit 206, a memory control unit 207, a D / A conversion unit 208, a memory 209, a CPU 210, a nonvolatile memory 211, a system timer 212, a system memory 213, and a display unit 101.

  The image processing unit 206 and the memory control unit 207 receive digital image data generated by the A / D conversion process in the imaging unit 203. The image processing unit 206 performs predetermined resizing processing such as pixel interpolation and reduction, color conversion processing, and the like on the digital image data received from the imaging unit 203 or the digital image data received from the memory control unit 207. . In the present embodiment, the image processing unit 206 can adjust the gain amount for the digital image data output from the imaging unit 203.

  It is assumed that the image processing unit 206 performs adjustment related to amplification or reduction of the gain amount for the acquired digital image data in accordance with an instruction from the CPU 210. That is, adjustment of the gain amounts of both the analog image data and the digital image data is performed based on the gain amount set by the CPU 210.

  The digital image data is sent to the CPU 210 after various processes are performed by the image processing unit 206, and exposure control, focus control, and the like are executed according to the luminance value of the subject. For example, TTL (through-the-lens) AF (autofocus) processing, AE (automatic exposure) processing, light control processing, AWB (auto white balance) processing, and the like. In the present embodiment, based on the digital image data sent from the image processing unit 206, the CPU 210 calculates the exposure amount when the subject is imaged, the position of the photographing lens 201, and the like. The CPU 210 executes exposure control and focus control based on the calculation result.

  Also, digital image data output from the imaging unit 203 is temporarily recorded in the memory 209 via the image processing unit 206 and the memory control unit 207. The memory 209 is a recording unit including a recording element such as a DRAM, and can record digital image data acquired by the imaging unit 203 and analog image data for display displayed on the display unit 101. Further, the memory 209 has a sufficient storage capacity capable of recording a predetermined number of still images, a moving image of predetermined time, and audio data. The memory 209 also serves as an image display memory (video memory).

  The digital image data temporarily recorded in the memory 209 is transmitted to the memory control unit 207. The memory control unit 207 converts the received digital image data into analog image data for display and transmits it to the display unit 101. The display unit 101 displays the received analog image data for display on the display unit 101 in accordance with an instruction from the CPU 210. By sequentially displaying analog image data for display on the display unit 101, it is possible to perform live view display of a through image obtained by imaging the subject. In addition, the through image can be displayed in live view not only on the display unit 101 but also on an electronic viewfinder (not shown).

  The nonvolatile memory 211 is a memory that can be electrically erased and stored, and is, for example, an EEPROM typified by a flash memory or the like. The nonvolatile memory 211 stores various data used in this embodiment. For example, a program executed in the camera 100, operation constants, various exposure conditions, calculation formulas used for processing in the camera 100, light emission conditions of the flash 217, and the like are stored in the nonvolatile memory 211. Note that the program executed in the camera 100 is a program for instructing the same operation as the flow shown in FIG.

  The CPU 210 not only executes various programs stored in the nonvolatile memory 211, but also comprehensively controls the overall operation of the camera 100. For example, the CPU 210 controls display of still images and moving images by controlling the memory 209, the memory control unit 207, the display unit 101, and the like. In addition, control instructions are given to the image processing unit 206, the memory control unit 207, a power source control unit 215 described later, and the like. It should be noted that a photometric calculation unit 218, a dimming calculation unit 219, a strobe control unit 220, and the like are provided inside the CPU 210.

  The photometric calculation unit 218 receives the digital image data acquired by the imaging unit 203 and calculates the luminance value of the subject imaged by the imaging unit 203. As a method for calculating a luminance value by the photometric calculation unit 218, first, image data (for one screen) acquired by the imaging unit 203 is divided into a plurality of blocks.

  Next, an average luminance value is calculated for each of these blocks. Then, a representative luminance value is calculated by integrating the average luminance values of all blocks. In the present embodiment, various processes to be described later are executed using this representative luminance value.

As a method for calculating the representative luminance value, any known method may be used.
For example, the luminance value is added after performing the weighting according to the difference between the average luminance value and the luminance value of the reference block (reference block) and the position of the block. A configuration may be adopted in which the weighted luminance value is used as the representative luminance value. The representative luminance value (hereinafter simply referred to as luminance value) calculated by the photometric calculation unit 218 is sent to the memory 209.

  Further, the photometric calculation unit 218 determines whether or not the subject needs to be illuminated with the strobe 217 based on the previously calculated luminance value. Depending on the result of this determination, whether or not the strobe 217 needs to emit light is set, and whether or not the light emission is necessary is recorded in the memory 209. Note that the first row and the second row described above are arranged as different rows among the rows of the image sensor 204.

  In the present embodiment, the odd-numbered rows of the image sensor 204 are the first rows for moving images, and the even-numbered rows are the second rows for still images. The dimming calculation unit 219 is dimming means for adjusting the light emission amount of the strobe 217 when the strobe 217 emits light. The dimming operation unit 219 performs a storage for moving images (hereinafter referred to as a first row) and a row for storing still images (hereinafter referred to as a second row) of the image sensor 204. Then, the image data acquired twice is compared, and the light emission amount of the flash 217 is calculated. The calculated light emission amount of the strobe 217 is recorded in the memory 209.

  The strobe control unit 220 reads from the memory 209 information on whether or not the strobe 217 needs to emit light and the amount of light emission set by the dimming calculation unit 219, thereby controlling the light emission control means (first control means). ). The strobe controller 220 also controls the light emission timing of the strobe 217 in the moving image acquisition process described later. Programs read from the nonvolatile memory 211 by the CPU 210, operation constants, variables, and the like are expanded in the system memory 213. A RAM is used as the system memory 213. The system timer 212 measures the time of a clock with a built-in time and timing used for various controls.

  Various operation members constituting the operation unit 105 are used for selecting various function icons displayed on the display unit 101, and functions are appropriately assigned to each scene by selecting a predetermined function icon. It is done. That is, each operation member of the operation unit 105 is used as various function buttons. A controller wheel 102 which is an operation member capable of rotating operation is used when a selection item is instructed together with a four-way button. When the controller wheel 102 is rotated, an electrical pulse signal corresponding to the operation amount (rotation angle, number of rotations, etc.) is generated. The CPU 210 analyzes this pulse signal and controls each part of the camera 100.

  The controller wheel 102 may be any operation member that can detect a rotation operation, such as a member that rotates itself or a member that does not rotate but detects a rotation operation with a touch sensor. The shutter button 103 has a first switch SW1 and a second switch SW2. The first switch SW1 is turned on when the shutter button 103 is half-pressed during the operation, whereby a signal instructing preparation for photographing is transmitted to the CPU 210. When the CPU 210 receives a signal with the first switch SW1 turned ON, the CPU 210 starts exposure control and focus control such as the AF processing, AE processing, AWB processing, and light control processing described above.

  The second switch SW2 is turned on when the shutter button 103 is fully pressed, and a signal instructing the start of imaging of the subject is transmitted to the CPU 210. When the CPU 210 receives a signal with the second switch SW2 turned ON, the CPU 210 reads it out as analog image data corresponding to the charge accumulated in the imaging unit 203. Next, the digital image data converted from the analog image data is written into the recording medium 130. At the same time, display analog image data converted from digital image data is displayed on the display unit 101 as a through image. The series of photographing operations described above is performed in response to turning on of the second switch SW2.

  The mode switch 104 is a switch for switching the operation mode of the camera 100 between various modes such as a still image storage mode, a moving image storage mode, and a playback mode. The still image storage mode includes, for example, an auto shooting mode, an auto scene determination mode, a manual mode, various scene modes serving as shooting settings for each shooting scene, a program AE mode, a custom mode, and the like. By operating the mode switch 104, it is possible to directly switch to one of these modes included in the still image storage mode.

  However, the present invention is not limited to such a configuration. For example, after switching to the still image storage mode with the mode switch 104, the operation mode is switched to one of the above-described modes included in the still image storage mode using another operation member. It may be. Similarly, the moving image storage mode may include a plurality of modes.

  The camera 100 includes a power supply unit 214 and a power supply control unit 215. The power supply unit 214 is a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, a NiMH battery, or a Lii battery, or an AC adapter, and supplies power to the power supply control unit 215. The power supply control unit 215 is configured by a battery detection circuit, a DC-DC converter, a switch circuit that switches a current-carrying block, and the like. The power supply control unit 215 detects the presence / absence of a battery in the power supply unit 214, the type of battery, the remaining battery level, etc., and controls the DC-DC converter based on the detection result and the instruction of the CPU 210 to obtain the necessary voltage. It supplies to each part including the recording medium 130 for a necessary period.

  The camera 100 includes an I / F (interface) 216 for enabling communication between the recording medium 130 and the CPU 210 when the recording medium 130 is mounted in a recording medium slot (not shown).

  In the present embodiment, each pixel constituting the image sensor 204 can be simultaneously driven and read out in units of rows. Therefore, the driving cycle and the reading cycle can be independently controlled for the first row and the second row described above.

  The operation unit 105 or the mode switching switch 104 is operated by the user, and in this embodiment, each pixel for imaging constituting the imaging device 204 is controlled independently in the first row and the second row. I can do it. In particular, since the subject is imaged independently in the first row and the second row, the readout cycle (frame rate) of the imaging signal corresponding to the accumulated charges is the first row and the second row. Independent control becomes possible. Therefore, the camera 100 of this embodiment can acquire a still image (image data) without reducing the frame rate of the moving image. In addition, since the frame rates of the first row and the second row can be controlled independently, it is possible to prevent the storage time of the still image from being limited.

  Hereinafter, the moving image acquisition process according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a flowchart for explaining the moving image acquisition process of the camera 100 which is the first embodiment of the imaging apparatus embodying the present invention. FIG. 4 is a timing chart for explaining the light emission timing of the strobe 217 and the storage timing of the image sensor 204 of the camera 100 which is the first embodiment of the imaging apparatus embodying the present invention. When the user gives an instruction to acquire a moving image, in step S101, the CPU 210 sets various conditions for imaging the subject for the moving image in accordance with the imaging signal output from the first row of the image sensor 204.

  As the imaging conditions to be set, according to instructions from the CPU 210 to each unit in the camera 100, an exposure amount, an exposure correction amount, a position of the photographing lens 201, and the like according to the luminance value of the subject are set. These imaging conditions are set by performing the above-described AE control, AWB control, focus control, and the like for moving image acquisition from the CPU 210 to each part of the camera 100. Note that the exposure amount in the present embodiment is a value for setting the brightness of an image to be acquired, and changes by changing the aperture value, accumulation time, gain amount (ISO sensitivity), and the like.

  Next, in step S102, the CPU 210 determines whether imaging of a subject is instructed for a still image. That is, the CPU 210 determines whether imaging of the subject for the still image is instructed during imaging of the subject for the moving image. When it is determined that acquisition of a still image has been instructed, the process proceeds to step S103, and when acquisition of a still image is not instructed, the process proceeds to step S109.

  Next, in step S103, the strobe controller 220 determines whether or not the strobe 217 is caused to emit light when the subject is imaged for a still image. If the strobe controller 220 determines that the strobe 217 is to emit light, the process proceeds to step S104. If it is determined that the strobe 217 is not to emit light, the process proceeds to step S108.

  Next, in step S104, it is determined whether the pre-flash can be performed before the next frame from the still image acquisition timing of the subject instructed in S102. The exposure period (E1) based on the shutter speed and the one frame period (T_falame) in the photographing condition setting set in S101 are defined. Also, the exposure of the next frame of moving image starts during the period (T_lumine) of the pre-flash + dimming calculation + strobe charge period + main flash from the still image acquisition timing (T_photo) instructed in S102 Judgment is made based on whether or not it falls within the time until timing.

T_falame‐E1 ≧ T_lumine
In the case of, after E1 ends, the process proceeds to S105 of the flow in which pre-light emission and main light emission are performed within the same frame as the still image acquisition timing (T_photo) to acquire a still image.

T_frame‐E1 <T_lumine
If it is, the flow proceeds to S112 of the flow for acquiring the still image by performing the pre-flash and the main flash at the frame next to the still image acquisition timing (T_photo).

  Next, in step S105, strobe pre-emission is performed with a desired light amount. Next, in step S106, dimming calculation and strobe charging in pre-flash are performed. The dimming calculation unit 219 is based on the previously acquired image data of still image illuminated by the pre-flash of the flash 217 and image data for still image not illuminated. The light control is performed for the main flash of the strobe 217. In addition, the flash 217 is charged in preparation for the next main light emission during the dimming calculation period.

  Next, main light emission is performed in step S107. FIG. 4A is a timing chart for explaining the light emission timing of the strobe 217 and the accumulation timing of the image sensor 204 of the camera 100 which is the first embodiment of the imaging apparatus embodying the present invention. The upper side in the figure shows the accumulation period (shaded part) and the reset period (black part) in the first row and the second row. The lower side of the figure shows the processing timing of each step in the flowchart of FIG.

  In the present embodiment, when capturing a still image by firing the flash 217 while imaging a subject for a moving image, the first row accumulation time (first accumulation time) E1 period By controlling so that the light emission of the strobe 217 does not overlap, it is possible to prevent the light emission of the strobe 217 from affecting the acquired moving image.

  Next, in step S108, the CPU 210 causes the subject to be imaged for a still image by the second row of the image sensor 204. The imaging timing is performed after the three reset periods of the second row in FIG. The three reset periods are the first reset when the strobe before the pre-flash is not illuminated, the second reset before the dimming calculation performed after the pre-flash, and then the main flash. And a third reset performed before the imaging timing. These resets are performed during the reset period of the first row.

  In step S <b> 109, the CPU 210 causes the subject to be imaged for a moving image by the first row of the image sensor 204. Note that, as illustrated in FIG. 4A, at this timing, the subject is imaged in a state where the subject is not illuminated by the flash 217. The acquired image data for the moving image of the non-light emitting subject is recorded in the memory 209. The acquired moving image data is recorded on the recording medium 130 as a recording moving image (image data). Further, the acquired image data for moving images is converted into display image data for display as a moving image by the memory control unit 207 in a state where image processing, compression / encoding, and the like are appropriately performed, and the display unit 101 Is displayed.

  Next, in step S110, the composition unit 221 executes a still image generation process for generating a recording still image. As described above, in the present embodiment, the still image generation processing includes the first pixel that is the accumulation row for moving image acquisition and the second accumulation row for still image acquisition. It is divided into lines. At this time, half of all the imaging pixels constituting the image sensor 204 are allocated to the first row, and the other half are allocated to the second row. Accordingly, the image data for the still image calculated in each of the steps described above is acquired as image data having the number of pixels that is half the number of pixels for imaging of the image sensor 204.

  On the other hand, if the pre-emission cannot be performed by the next frame after returning to S104, the process proceeds to step S112, and the CPU 210 resets the exposure amount in the first row of the second frame of the imaging unit 203. Specifically, the accumulation time in the first row is set so that when the flash 217 is fired and the subject is captured for a still image, the flash 217 does not affect the moving image acquired in parallel. The Details of the accumulation time will be described later.

  The gain amount of the digital image data acquired in the first row in the first row exposure reset in step S112 is set so as to compensate for the exposure amount changed by resetting the accumulation time. Hereinafter, the accumulation time and the light emission timing of the strobe 217 in the first and second rows of the image sensor 204 will be described with reference to FIG.

  FIG. 4B is a timing chart illustrating the light emission timing of the strobe 217 and the accumulation timing of the image sensor 204 of the camera 100 which is the first embodiment of the imaging apparatus embodying the present invention. The upper side in the figure shows the accumulation period (shaded part) and the reset period (black part) in the first row and the second row. The lower side of the figure shows the processing timing of each step in the flowchart of FIG. In the present embodiment, the reset period is a period from the end of the moving image accumulation to the start of the next moving image accumulation in the first row.

  As shown in FIG. 4 (b), in the present embodiment, when capturing a still image by firing the flash 217 while capturing a subject for moving images, the accumulation time of the first row is instructed. (First accumulation time) The accumulation time of the next frame (second accumulation time) is changed to E2 with respect to E1. In other words, the accumulation time for acquiring the moving image in the image sensor 204 at the time of low luminance is extended. With this configuration, it is possible to prevent the light emission of the flash 217 from affecting the acquired moving image. The CPU 210 sets the accumulation time in the image sensor 204.

As described above, as the second accumulation time E2, an accumulation time is set such that the influence of the light emission of the strobe 217 does not affect the moving image. The state where the second accumulation time E2 is set in the first row is maintained until the pre-flash and the main flash of the strobe 217, which will be described later, are completed. In the control of step S112 in FIG. 4B, the gain amount is also reset in response to shortening the accumulation time of the first row. With this configuration, it is possible to compensate for the reduced exposure amount by shortening the accumulation time. Specifically, if the accumulation time before resetting is E1, and the reset period of the first row after resetting is Tres, the gain amount GainUp to be increased is calculated using the equation (1):
GainUp = E1 / (E1-Tres)
Can be calculated as

  As described above, in the control of step S112 in FIG. 4B, the CPU 210 resets the accumulation time of the first row and the gain amount of the image data acquired at the accumulation time. That is, the CPU 210 sets the accumulation time in the image sensor 204 (second control means) and sets the gain amount of the acquired image data.

  Returning to FIG. 4B, the strobe controller 220 performs pre-flash control of the strobe 217 in step S113. As shown in FIG. 4 (b), the light emission timing of the strobe 217 is set in the reset period (first period) of the first row in which the subject is imaged for moving images.

  Next, the process proceeds to S114, and after the light control calculation for the main flash of the strobe 217 and the strobe charging period, the strobe controller 220 performs the main flash of the strobe 217 in the next S107. The light emission timing of the strobe 217 is controlled by the strobe controller 220 so that the light emission from the start to the end of the first row is reset during the reset period (first period) of the first row.

  If acquisition of a still image is not instructed in step S102, step S110 is skipped, and the process proceeds to step S111 without executing still image generation processing. In step S111, the CPU 210 determines whether or not to continue the moving image acquisition. When the acquisition of the moving image is continued, the process returns to step S102. When the acquisition of the moving image is ended, the acquisition of the moving image is ended, and the moving image acquisition process is ended. The above is the moving image acquisition process of the present embodiment.

  If the relationship between the light emission timing of the strobe 217 and the accumulation time of each row of the image sensor 204 described above is used, the influence of the light emission of the strobe 217 can be suppressed and moving image data can be acquired. With this configuration, the subject can be imaged with the strobe 217 being emitted for a still image without changing the frame rate of the moving image. At this time, since the frame rate is controlled independently for the first row for moving images and the second row for still images of the image sensor 204, when acquiring image data for still images, The accumulation time of the second row is not limited.

  As described above, the camera 100 according to the present embodiment is in the state of causing the strobe 217 to emit light in the second row of the image sensor 204 during the acquisition of the moving image and in the reset period of the first row of the image sensor 204. Can capture a subject for a still image. With this configuration, it is possible to suppress the light emission of the flash 217 from affecting the acquired moving image.

  Further, in the present embodiment, since a moving image and a still image can be acquired independently with only one image sensor 204, the degree of freedom of accumulation time of the moving image and the still image that can be set by the user can be improved. . In particular, with regard to still images, the accumulation start time is limited only by the accumulation time of the moving image, and the accumulation time is not limited. Therefore, the camera 100 according to the present embodiment is not limited in the storage time of a still image, even when acquiring a moving image and a still image with the flash 217 being lit by a single image sensor. It is possible to suppress the light emission of 217 from affecting the moving image.

In the present embodiment, the odd-numbered rows of the image sensor 204 are the first rows for moving images and the even-numbered rows are the second rows for still images, but the present invention is not limited to this.
For example, the first row and the second row may be any row of the image sensor 204 as long as the resolution of moving images and still images is ensured to some extent.

  In the above-described embodiment, the digital camera 100 has been described as an example of an imaging apparatus that implements the present invention. However, the present invention is not limited to this. For example, the present invention, such as a portable device such as a digital video camera or a smartphone, can be applied to various imaging devices within the scope of the gist thereof.

203 Imaging unit
204 Image sensor
210 System controller (CPU)
217 Strobe (flash means)
220 Strobe controller

Claims (5)

It has a plurality of imaging pixels arranged in the row direction and the column direction, and the reading cycle can be controlled independently in the first row and the second row different from the first row. A charge storage type imaging device;
First control means for controlling the light emission of the light emitting means for illuminating the subject;
Second control means for setting the accumulation time of the first row and the second row of the image sensor in accordance with the set shutter speed;
When the first control unit causes the light-emitting unit to emit light and capture an image of a subject for a still image in the second row, the accumulation for moving image ends in the first row, or a still image shooting instruction The light emitting means is caused to emit light according to the period from the timing of until the start of accumulation for the next video,
The imaging apparatus according to claim 2, wherein the second control unit causes accumulation of still images in the second row in a period at least partially overlapping a period in which the light emitting unit emits light. When the subject is imaged for a still image in the second row, the second control means has a sufficiently high shutter speed set for the moving image frame rate, and the second control means starts from the timing of the still image shooting instruction. When the light emitting means can emit light during the period until the accumulation of the moving image starts, the period from the start to the end of the light emitting means falls within the period until the accumulation of the moving image for the next frame is started. The imaging apparatus according to claim 1, wherein the light emitting unit emits light. When the subject is imaged for a still image in the second row, the second control means has a slow shutter speed set for the frame rate for the moving image, or the timing from the timing of the still image shooting instruction. If the period until the storage for the moving image is started is short and the light emitting means cannot emit light, the first row is set according to the storage time of the first row of the next frame set by the second control means. 2. The imaging apparatus according to claim 1, further comprising third control means for setting a gain amount of an image acquired by a row. It has a plurality of imaging pixels arranged in the row direction and the column direction, and the reading cycle can be controlled independently in the first row and the second row different from the first row. A method for controlling an imaging device including a charge storage type imaging device,
A first control step for controlling the light emission of the light emitting means for illuminating the subject;
A second control step of setting an accumulation time of the first row and the second row of the image sensor in accordance with a set shutter speed;
In the first control step, when the subject is imaged for the still image in the second row by causing the light emitting means to emit light, the accumulation for the moving image ends in the first row, or the still image shooting instruction The light emitting means is caused to emit light according to the period from the timing of until the start of accumulation for the next video,
In the second control step, the still image accumulation in the second row is performed in a period at least partially overlapping with a period during which the light emitting unit emits light. .   A computer-readable program for causing a computer to execute the control method for an imaging apparatus according to claim 4.