Electronic device and control method thereof

Abstract

To stably perform continuous image capturing at a high frequency while reducing an influence of flicker for a captured image.SOLUTION: There are included: am image sensor that captures an image; control means that controls the image sensor so as to obtain images by repeatedly capturing an image of a subject, and controls the image sensor so as to output a detection signal for detecting flicker during a period since capturing of an Nth image (N is a natural number) is performed to capturing of an N+1th image is performed; calculation means that calculates information relating to flicker on the basis of the detection signal; selection means that selects any one of Nth information and N-1th information in accordance with a predetermined condition; and determination means that determines capturing timing of the N+1th image on the basis of the selected Nth information or the selected N-1th information.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an electronic device and a control method thereof, and more particularly to a technique for capturing an image while reducing the effects of flicker. [Background technology]

[0002] 2. Description of the Related Art In recent years, imaging devices such as digital cameras have become increasingly sensitive, making it possible to capture images with high-speed shutters such as 1 / 4000 seconds or 1 / 8000 seconds.

[0003] When such a high-speed shutter is used to capture multiple images in continuous shooting mode or to shoot a video under an artificial light source with a variable light intensity (hereinafter referred to as a "flicker light source"), the exposure varies from frame to frame due to the blinking of light caused by the flicker light source. In addition, if the change in the amount of light during charge accumulation is large, exposure unevenness appears prominently in the vertical direction of one frame of image. Even in the case of single-shot shooting of a still image, depending on the timing of charge accumulation, exposure unevenness may appear or an image with the desired brightness may not be obtained.

[0004] To address this problem, a method is known for detecting flicker and reducing the effects of flicker by performing exposure at the peak timing when the amount of flicker light is at its peak, when the change in brightness due to the light source is the smallest.

[0005] The flicker frequency is twice the commercial power frequency, so it is either 100Hz or 120Hz. Therefore, in order to perform exposure at the peak timing of the flicker, the fundamental frequency (100Hz or 120Hz) and peak timing of the flicker are detected in advance, and exposure is performed in synchronization with the peak timing of the flicker.

[0006] On the one hand, it is known that the frequency of the commercial power supply in Japan fluctuates within a range of about ±0.3 Hz with respect to the basic 50 Hz or 60 Hz. Since the frequency of flicker is twice the frequency of the commercial power supply, the frequency of the flicker of the light source is 100 ± 0.6 Hz or 120 ± 0.6 Hz. Therefore, if the detection operation of the peak timing is not performed periodically, it will gradually shift, and the influence of the flicker cannot be reduced.

[0007] Therefore, by performing the detection operation of the peak timing between frames of continuous shooting or video shooting, it is possible to control so that the shooting timing does not deviate from the peak timing of the flicker. However, in order to detect the peak timing of the flicker, since it is necessary to perform the corresponding process, the continuous shooting speed will decrease.

[0008] Regarding this problem, Patent Document 1 detects the flicker frequency with high accuracy before the start of continuous shooting, and by omitting the flicker detection process between continuous shooting frames, high-speed continuous shooting is performed while reducing the influence of the flicker. And until a certain time elapses from the time of flicker detection, the difference between the actual flicker frequency and the detected flicker frequency is small, and it is disclosed that the flicker detection process between continuous shooting frames can be omitted on the assumption that the exposure unevenness is within the required accuracy.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0010] However, in the prior art disclosed in Patent Document 1, when a certain period of time has elapsed since the time when flicker was detected, it is assumed that the exposure unevenness does not meet the required accuracy, and flicker detection is performed between consecutive frames of continuous shooting, and the continuous shooting sequence is switched to a low-speed one. Therefore, there is a problem that the continuous shooting speed becomes slow.

[0011] In addition, every time a certain period of time elapses, since the continuous shooting speed switches between high speed and low speed, there is a problem that stable high-speed continuous shooting cannot be performed.

[0012] The present invention has been made in view of the above problems, and an object thereof is to enable high-speed and stable shooting while reducing the influence of flicker on the captured image.

Means for Solving the Problems

[0013] To achieve the above object, an electronic device of the present invention includes an imaging element that captures an image, controls the imaging element so as to repeatedly capture a subject to obtain an image, and after performing imaging for obtaining the Nth (N is a natural number) image, until performing imaging for obtaining the (N + 1)th image, control means for controlling the imaging element to output a detection signal for detecting flicker, arithmetic means for calculating information regarding flicker based on the detection signal, in accordance with a predetermined condition regarding the time required for arithmetic based on the detection signal, after performing imaging corresponding to the Nth image, selection means for selecting either the Nth information calculated based on the detection signal output until performing imaging corresponding to the (N + 1)th image and the (N - 1)th information calculated one before the Nth information, and determination means for determining the timing of imaging corresponding to the (N + 1)th image based on the selected Nth information or the (N - 1)th information. wherein the predetermined condition is information regarding whether the calculation of the N-th information is completed by the time of determining the imaging timing corresponding to the (N + 1)-th image, and the selection means selects the N-th information when it is determined that the calculation of the N-th information is completed, and selects the (N - 1)-th information when it is determined that the calculation of the N-th information is not completed to do.

Effects of the Invention

[0014] According to the present invention, it is possible to perform high-speed and stable shooting while reducing the influence of flicker on the captured image.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0016] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential for the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0017] In this embodiment, a digital mirrorless camera will be described as an example. However, the present invention can be applied to various electronic devices as long as they have a live view image display or a video shooting function. For example, it can be applied to smartphones, camcorders, game machines with cameras, and the like.

[0018] <First Embodiment> FIG. 1 is a diagram showing a schematic configuration of a digital mirrorless camera in the implementation of the present invention, mainly including a camera body 100 and a photographing lens 200. In the camera body 100, 101 is an imaging element such as a CCD or a CMOS including an infrared cut filter, a low-pass filter, etc. An image of a subject is formed on the light receiving surface by the photographing lens 200. The imaging element 101 photoelectrically converts the received image of the subject, and an image based on the obtained electrical signal is displayed as a live view or recorded as a photographed image. Further, the electrical signal obtained from the imaging element 101 is also used for flicker detection. In the imaging element 101, the charge accumulation time can be controlled according to the shutter speed set as photographing setting information.

[0019] 102 is a shutter, and by opening for a predetermined time during photographing, the exposure time of the imaging element 101 can be controlled.

[0020] The display unit 103 is composed of, for example, a TFT liquid crystal panel or the like. During framing, an image acquired by the imaging element 101, various photographing setting information, etc. are displayed in real time to realize a live view. Also, according to the user's operation, the photographed image can be displayed for the user to confirm. Further, a touch panel may be arranged on the display unit 103 and used as an operation member, and by the touch panel detecting the user's touch operation on an icon or the like displayed on the display unit 103, a function linked to the display of the touch position can be operated.

[0021] The CPU 104 controls each part of the camera body 100. The CPU 104 also controls the imaging element 101 and the display unit 103. Further, the CPU 104 performs calculations related to flicker detection based on the image photographed by the imaging element 101. In the calculations related to flicker detection, the frequency of the flicker light source, the peak timing of the light amount of the flicker, etc. are obtained.

[0022] Next, the photographing lens 200 will be described. 201 is a lens group including a focus lens, and focus adjustment can be performed by driving the focus lens. In FIG. 1, the lens group 201 is represented by a single lens, but actually it is composed of a plurality of lenses. 202 is a diaphragm that adjusts the amount of light taken into the camera. 203 is a CPU that controls each part of the photographing lens 200. In addition to controlling the lens group 201 and the diaphragm 202, by communicating with the CPU 104 on the camera body 100 side, information such as the focus position and the diaphragm can be exchanged between the camera body 100 and the lens group 201 and the diaphragm 202.

[0023] Next, with reference to FIG. 2, the photographing process in the first embodiment will be described. In the following description, since known techniques can be used for the method of acquiring a signal for detecting flicker (hereinafter referred to as "flicker detection signal") and the flicker calculation method for detecting flicker from the flicker detection signal, the description thereof will be omitted.

[0024] First, in S100, when a photographing instruction operation by the user, such as pressing the shutter release button, is performed from the state where the power of the camera body 100 is turned on, the process proceeds to S101.

[0025] In S101, the CPU 104 performs charge accumulation for flicker detection using the imaging element 101 to obtain a flicker detection signal.

[0026] Next, in S102, the CPU 104 performs a flicker calculation for detecting flicker information using the flicker detection signal obtained in S101. In the flicker calculation, determination of the presence or absence of flicker occurrence, and detection of the flicker frequency and the flicker peak timing are performed when flicker occurs.

[0027] In S103, the CPU 104 sets the image quality parameters for still image exposure for the imaging device 101. Also, when flicker is detected in S102, the CPU 104 determines the still image exposure time so as to perform still image exposure at a timing that matches the peak timing of the flicker. On the other hand, when flicker is not detected in S102, since there is no need to consider the peak timing of the flicker, control is performed so as to perform still image exposure such that the delay time from the shooting instruction to the shooting is as short as possible.

[0028] In S104, the CPU 104 controls the imaging device 101 and the shutter 102 so as to perform still image exposure at the timing determined in S103. Note that in the still image exposure performed at a timing that matches the peak timing when flicker is detected, the imaging device 101 may be controlled by an electronic shutter while the shutter 102 is open.

[0029] In S105, the CPU 104 checks whether the shooting operation by the user is continuing. If the shooting operation is continuing, the process proceeds to S106. If the shooting operation is not continuing, the shooting is terminated.

[0030] In S106, the CPU 104 determines the presence or absence of flicker from the previous flicker calculation result. If flicker is occurring, the process proceeds to S107. If flicker is not occurring, the process proceeds to S119.

[0031] When flicker is occurring, in S107 the CPU 104 predicts the next still image exposure time. The prediction of the next still image exposure time is performed in consideration of the continuous shooting speed, the total time such as the length of the accumulation time for the live view image output between consecutive still image exposures, the driving time of the aperture 202 for appropriate exposure of the next still image shooting, the peak timing of the flicker, and the previous still image exposure time. That is, the next still image exposure time is the time after multiplying the previous still image exposure time by an integer multiple of the flicker period.

[0032] In addition, since the still image exposure time also varies depending on the user's shooting settings, the next still image exposure time is predicted taking into account the user's shooting settings. Examples of the user's shooting settings include light control by flash shooting settings and changes in the still image readout time due to the still image quality settings. Since the shooting preparation and the processing after the still image exposure change depending on these settings, the interval between the still image exposures changes.

[0033] In S108, the CPU 104 determines whether the flicker calculation can be completed by the next still image exposure time predicted in S107 (predetermined condition). If it is determined that it cannot be completed, the process proceeds to S109, and if it is determined that it can be completed, the process proceeds to S114.

[0034] Here, the processing in the case where it is determined that the flicker calculation performed after S109 cannot be completed will be further described with reference to the timing chart shown in FIG. 3(a).

[0035] In S109, after the Nth (N is a natural number) still image exposure and the accumulation of the live view image, the CPU 104 accumulates the flicker detection signal in the same manner as in S101. At this time, the CPU 104 controls to accumulate the flicker detection signal at a timing close to the still image exposure after securing the shooting preparation period so as to be in time for the next still image exposure. By this accumulation timing control of the flicker detection signal, the interval between the accumulation time of the flicker detection signal and the still image exposure time can be shortened, so that the exposure unevenness of the still image due to the fluctuation of the flicker light source can be made smaller.

[0036] Figure 3 In the timing chart shown, an example is shown in which the accumulation of the flicker detection signal is performed after the end of the accumulation of the live view image. However, when charge accumulation and readout are possible within the same period between different lines of the image sensor 101, it may be controlled to accumulate the flicker detection signal during the accumulation of the live view image. Thereby, since the waiting time until the completion of the accumulation of the flicker detection signal can be shortened, the shooting preparation can be advanced earlier.

[0037] Further, instead of accumulating the live view images, the captured still images may be displayed on the display unit 103 in place of the live view images. Thereby, since the accumulation of the live view images can be omitted, the preparation for shooting can be advanced quickly.

[0038] In S110, the CPU 104 sets the peak timing of the flicker of the flicker operation result (the N - 1th information) performed after the exposure of the (N - 1)th still image to be used for calculating the exposure time of the (N + 1)th still image. In S111, the CPU 104 performs the shooting preparation for the exposure of the (N + 1)th still image in the same manner as S103 using the peak timing set in S110.

[0039] In S112, the CPU 104 performs a flicker operation using the flicker detection signal obtained in S109 in the same manner as S102. Here, the CPU 104 performs the shooting preparation in S111 and the flicker operation in S112 in parallel. This is because in order to perform the next still image exposure at the time according to the continuous shooting speed, it is necessary to complete the parameter setting for the still image exposure before the start of the still image exposure. In FIG. 3(a), it is assumed that the flicker operation is completed before the start of the still image exposure, but if it is not completed, the flicker operation may be continued during the still image exposure.

[0040] In S113, the CPU 104 controls the imaging device 101 and the shutter 102 to perform still image exposure at a timing that coincides with the peak timing of the flicker in the same manner as S104.

[0041] By the above-described processing, when the flicker operation is not completed by the time of the next still image exposure, the shooting preparation for the next still image exposure is based on the flicker operation result obtained in the previous frame toTherefore, the continuous shooting speed can be increased. Also, since the accumulation of the flicker detection signal and the flicker calculation are performed during the still image exposure, the continuous shooting speed can be stabilized.

[0042] Next, the processing when it is determined that the flicker calculation can be completed in S108, which is performed after S114, will be described with reference to the timing chart shown in FIG. 3(b).

[0043] In S114, after the accumulation of the Nth still image exposure and the live view image, the CPU 104 accumulates the flicker detection signal in the same manner as in S101. At this time, when the luminance of the external light is low, the accumulation time of the live view image may be increased in order to obtain a display on the display unit 103 or an evaluation image for focusing on the subject. The CPU 104 controls so as to accumulate the flicker detection signal at a timing close to the still image exposure while securing a shooting preparation period so as to be in time for the next still image exposure time.

[0044] In S115, a flicker calculation is performed based on the flicker detection signal obtained by the accumulation in S114. In the subsequent S116, the CPU 104 sets the peak timing of the flicker, which is the flicker calculation result (the Nth information) in S115, to be used for calculating the exposure time of the (N + 1)th still image.

[0045] In S117, the CPU 104 performs shooting preparation for the (N + 1)th still image exposure in the same manner as in S103.

[0046] In S118, the CPU 104 controls the imaging device 101 and the shutter 102 so as to perform still image exposure at a timing that coincides with the peak timing of the flicker in the same manner as in S104.

[0047] Finally, the case where it is determined in S106 that no flicker is occurring will be described. Even if it is determined by the previous flicker calculation that no flicker is occurring, flicker may occur during shooting due to a change in the shooting angle of view. Therefore, even if it is determined that no flicker is occurring, it is advisable to acquire the flicker detection signal and perform the flicker calculation.

[0048] In order to perform shooting in accordance with the peak timing of flicker in the next still image exposure, in S119, the CPU 104 accumulates the flicker detection signal, and in S121, the CPU 104 performs a flicker calculation. When flicker is detected here, in S106 at the time of the next still image exposure, it becomes YES, and the processes after S107 described above are performed.

[0049] In parallel with the flicker calculation process in S121, in S120, the CPU 104 prepares for still image shooting in the same manner as in S103. Since no flicker is detected here, the still image exposure time is determined so as to perform still image exposure without considering the peak timing of flicker.

[0050] In S122, the CPU 104 controls the imaging device 101 and the shutter 102 to perform still image exposure.

[0051] Note that in S120 and S122, the detection result of flicker is not reflected in the still image exposure, but it is also possible to perform still image exposure in accordance with the peak timing of flicker at that time using the flicker detection result when flicker was detected in the past.

[0052] As described above, according to the first embodiment, it is possible to dynamically select which flicker calculation result to use for calculating the next still image exposure time based on whether the flicker calculation is completed by the time of the next still image exposure. By this selection, it is possible to suppress uneven exposure without reducing the continuous shooting speed.

[0053] In the above-described embodiment, the accumulation of the flicker detection signal and the flicker calculation are always performed between still image exposures. However, the present invention is not limited to this. For example, an effective time for the flicker calculation result may be provided, and the accumulation of the flicker detection signal and the flicker calculation within the effective time may be controlled so as not to be performed.

[0054] <Second Embodiment> Next, a second embodiment of the present invention will be described. FIG. 4 of With reference to the flowchart, a sequence for performing continuous shooting at the peak timing of flicker in the second embodiment will be described. Note that the same step numbers are assigned to the processes similar to those in the flowchart of FIG. 2 described above, and the description thereof will be omitted.

[0055] The difference between the second embodiment and the first embodiment is that in S206, based on the drive mode (predetermined conditions), it is determined at which timing the calculation result of the flicker calculation obtained is used for which still image exposure. As an example, when there are high speed, medium speed, and low speed drive modes, it is assumed that 30 frames / second for high speed, 15 frames / second for medium speed, and 3 frames / second (shooting frequency) are set for each drive mode. In S206, when it is determined that the drive mode is high speed or medium speed, the CPU 104 performs the processes of S109 to S113.

[0056] When the drive mode is low speed, the CPU 104 performs the processes of S114 to S118. When the drive mode is low speed, since the interval between still image exposures is long, sufficient time can be ensured for the accumulation of the flicker detection signal and the flicker calculation. Therefore, the CPU 104 waits for the flicker calculation and controls to perform the next still image exposure in accordance with the peak timing of the flicker.

[0057] As described above, according to the second embodiment, by determining whether the calculation result of the flicker calculation is used for the next still image exposure or the previous still image exposure according to the continuous shooting speed, it is possible to simply distribute the processing.

[0058] In the second embodiment, the processing was distributed according to the drive mode. However, a threshold value may be provided, and the processing may be distributed by comparing the continuous shooting speed (shooting frequency) with the threshold value (predetermined conditions). For example, when the continuous shooting speed is lower than the threshold value, the calculation result of the flicker calculation is used for the next still image exposure, and when it is equal to or higher than the threshold value, the calculation result of the flicker calculation is used for the still image exposure of the next one.

[0059] Also, in the first and second embodiments described above, the control during continuous shooting of still images has been described, but it may be applied to the control during video shooting. In that case, the continuous shooting speed may be replaced with the frame rate for control, and the still image exposure becomes the exposure of the image of each frame of the video.

[0060] <Other Embodiments> Note that the present invention may be applied to a system composed of a plurality of devices (for example, a host computer, an interface device, a scanner, a video camera, etc.), or may be applied to a device composed of one device (for example, a copying machine, a facsimile device, etc.).

[0061] Also, the present invention can be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and one or more processors in the computer of the system or device reading and executing the program. It can also be realized by a circuit (for example, an ASIC) that realizes one or more functions.

[0062] The invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the invention. Therefore, claims are attached to disclose the scope of the invention.

Description of Reference Numerals

[0063] 100: Camera body, 101: Image sensor, 102: Shutter, 103: Display unit, 104: CPU, 200: Shooting lens, 201: Lens group, 202: Aperture, 203: CPU

Claims

1. an image sensor for capturing an image; control means for controlling the image sensor to repeatedly capture an object to obtain an image, and after capturing an image for obtaining the N-th (N is a natural number) image, controlling the image sensor to output a detection signal for detecting flicker until capturing an image for obtaining the (N + 1)-th image; arithmetic means for calculating information regarding flicker based on the detection signal; selection means for selecting either the N-th information calculated based on the detection signal output between capturing an image corresponding to the N-th image and capturing an image corresponding to the (N + 1)-th image after capturing an image corresponding to the N-th image according to a predetermined condition regarding time required for calculation based on the detection signal, and the (N - 1)-th information calculated one before the N-th information; determination means for determining the timing of capturing an image corresponding to the (N + 1)-th image based on the selected N-th information or (N - 1)-th information; comprising; wherein the predetermined condition is information regarding whether calculation of the N-th information is completed before determining the timing of capturing an image corresponding to the (N + 1)-th image, and the selection means selects the N-th information when it is determined that calculation of the N-th information is completed, and selects the (N - 1)-th information when it is determined that calculation of the N-th information is not completed. An electronic device characterized by the above.

2. The electronic device according to claim 1, wherein the N-th information and the (N - 1)-th information each include information regarding the presence or absence of flicker occurrence, the frequency of flicker, and changes in the amount of light of flicker.

3. when the (N - 1)-th information indicates that flicker is occurring, further comprising prediction means for predicting the timing of capturing an image corresponding to the (N + 1)-th image based on at least the total time of the accumulation time corresponding to the N-th image, the accumulation time of the detection signal, and the time required for preparation for capturing an image corresponding to the (N + 1)-th image, and changes in the frequency and amount of light of flicker obtained from the (N - 1)-th information; The electronic device according to claim 1, wherein the selection means makes the selection based on the predicted timing of capturing an image corresponding to the (N + 1)-th image.

4. When the N-1th information indicates that flicker is occurring, the determination means determines the imaging timing corresponding to the (N + 1)th image so that the imaging timing corresponding to the (N + 1)th image is the timing at which the light amount of the flicker peaks. The electronic device according to claim 2 or 3, characterized in that.

5. When the N-1th information indicates that flicker is occurring, the determination means is based on the selected Nth information or the N-1th information, from the imaging timing corresponding to the Nth image, at least, the accumulation time corresponding to the Nth image, the accumulation time of the detection signal, and the total time of the time required for the preparation of imaging corresponding to the (N + 1)th image, and the timing closest to an integer multiple of the flicker period is determined as the imaging timing corresponding to the (N + 1)th image. The electronic device according to claim 4, characterized in that.

6. An image sensor for imaging an image, Controlling the image sensor to repeatedly image a subject to obtain an image, and after imaging for obtaining the Nth (N is a natural number) image, outputting a detection signal for detecting flicker until imaging for obtaining the (N + 1)th image is performed. Control means for controlling the image sensor; Calculation means for calculating information regarding flicker based on the detection signal; According to a predetermined condition regarding the time required for the calculation based on the detection signal, the Nth information calculated based on the detection signal output between imaging corresponding to the Nth image and imaging corresponding to the (N + 1)th image, and the N-1th information calculated one before the Nth information. Selection means for selecting either; Determination means for determining the imaging timing corresponding to the (N + 1)th image based on the selected Nth information or the N-1th information having The predetermined condition is information regarding the frequency of imaging a subject to obtain the image, The selection means selects the Nth information in the case of the first frequency, and selects the N-1th information in the case of the second frequency higher than the first frequency. The electronic device characterized by that.

7. An image sensor for imaging an image, controlling the image sensor to repeatedly image a subject to obtain images, and after imaging for obtaining the Nth (N is a natural number) image, controlling the image sensor to output a detection signal for detecting flicker until imaging for obtaining the (N + 1)th image is performed; calculation means for calculating information regarding flicker based on the detection signal; selection means for selecting either the Nth information calculated based on the detection signal output between imaging corresponding to the Nth image and imaging corresponding to the (N + 1)th image after imaging corresponding to the Nth image according to a predetermined condition regarding the time required for calculation based on the detection signal, and the (N - 1)th information calculated one before the Nth information; determination means for determining the timing of imaging corresponding to the (N + 1)th image based on the selected Nth information or (N - 1)th information; having; the predetermined condition is information regarding the frequency of imaging a subject to obtain the image, wherein when the frequency is lower than a predetermined threshold value, the Nth information is selected, and when the frequency is equal to or higher than the predetermined threshold value, the (N - 1)th information is selected. An electronic device characterized by this.

8. The electronic device according to claim 6 or 7, characterized in that the Nth information and the (N - 1)th information each include information regarding the presence or absence of flicker occurrence, the frequency of flicker, and the change in the amount of light of flicker.

9. The electronic device according to claim 8, characterized in that when the (N - 1)th information indicates that flicker is occurring, the determination means determines that the timing of imaging corresponding to the (N + 1)th image is the timing at which the amount of light of the flicker peaks.

10. When the N - 1th information indicates that flicker is occurring, the determining means, based on the selected Nth information or the N - 1th information, determines, from the imaging timing corresponding to the Nth image, at least a timing that is longer than the total time of the accumulation time corresponding to the Nth image, the accumulation time of the detection signal, and the period required for preparation for imaging corresponding to the (N + 1)th image, and is closest to a timing that is an integer multiple of the frequency and the period of the flicker, as the imaging timing corresponding to the (N + 1)th image. The electronic device according to claim 9, characterized in that.

11. further comprising setting means for setting the valid time of the information, When the valid time has not elapsed since the arithmetic means last calculated the information, the imaging element does not output the detection signal, and the determining means determines to use the information last calculated. The electronic device according to any one of claims 1 to 10, characterized in that.

12. The electronic device according to any one of claims 1 to 11, characterized in that the image is a still image.

13. The electronic device according to any one of claims 1 to 11, characterized in that the image is an image of each frame of a moving image.

14. An imaging element for imaging an image, control means for controlling the imaging element to repeatedly image a subject to obtain an image, and controlling the imaging element to output a detection signal for detecting flicker between the exposure of the first still image and the exposure of the second still image; arithmetic means for calculating information regarding flicker based on the detection signal; determining means for determining the imaging timing in the exposure of the second still image based on either the first information regarding flicker calculated between the exposure of the first still image and the exposure of the second still image and the second information regarding flicker calculated before the first information is calculated; and The determining means selects the first information when the calculation of the first information is completed by the time of determining the imaging timing of the exposure of the second still image, and selects the second information if the calculation of the first information is not completed. An electronic device characterized by that.

15. An imaging element for imaging an image, controlling the imaging element to repeatedly image a subject and acquire an image, and also controlling the imaging element to output a detection signal for detecting flicker between the exposure of the first frame of the moving image and the exposure of the second frame of the moving image; an arithmetic unit that calculates information regarding flicker based on the detection signal; determination means for determining the shooting timing in the exposure of the second frame of the moving image based on either first information regarding flicker calculated between the exposure of the first frame of the moving image and the exposure of the second frame of the moving image, and second information regarding flicker calculated before the first information is calculated; The determination means selects the first information when the calculation of the first information is completed by the time of determining the shooting timing in the exposure of the second frame of the moving image, and selects the second information if the calculation of the first information is not completed. An electronic device characterized by this.

16. The electronic device according to claim 14 or 15, wherein the arithmetic means calculates information regarding the flicker using a detection signal obtained during accumulation of a live view image.

17. An imaging element that images an image; controlling the imaging element to repeatedly image a subject and acquire an image, and also controlling the imaging element to output a detection signal for detecting flicker between the exposure of the first still image and the exposure of the second still image; an arithmetic unit that calculates information regarding flicker based on the detection signal; determination means for determining the shooting timing in the exposure of the second still image based on either first information regarding flicker calculated between the exposure of the first still image and the exposure of the second still image, and second information regarding flicker calculated before the first information is calculated; The determination means selects either the first information and the second information used for determining the shooting timing in the exposure of the second still image based on information regarding the frequency of repeatedly imaging a subject and imaging still images; The determination means selects the first information when the frequency is a first frequency, and selects the second information when the frequency is a second frequency higher than the first frequency. An electronic device characterized by this.

18. An imaging device that captures an image, control means for controlling the imaging device to repeatedly capture a subject to obtain an image, and for controlling the imaging device to output a detection signal for detecting flicker between the exposure of the first frame of the moving image and the exposure of the second frame of the moving image; calculation means for calculating information regarding flicker based on the detection signal; determination means for determining the shooting timing in the exposure of the second frame of the moving image based on either first information regarding flicker calculated between the exposure of the first frame of the moving image and the exposure of the second frame of the moving image, and second information regarding flicker calculated before the first information is calculated; and the determination means selects either the first information and the second information to be used for determining the shooting timing in the exposure of the second frame of the moving image based on a frame rate, which is information regarding the frequency of obtaining frames of the moving image, wherein the determination means selects the first information when the frame rate is lower than a predetermined threshold, and selects the second information when the frame rate is equal to or higher than the predetermined threshold. An electronic device characterized by this.

19. The electronic device according to any one of claims 14 to 18, wherein the first information and the second information include information regarding the presence or absence of flicker, the frequency of flicker, and the change in light amount of flicker.

20. a control step of controlling the imaging device to repeatedly capture a subject to obtain an image, and after imaging to obtain the Nth (N is a natural number) image, controlling the imaging device to output a detection signal for detecting flicker between the imaging to obtain the Nth image and the imaging to obtain the (N + 1)th image; a calculation step of calculating information regarding flicker based on the detection signal; a selection step of selecting either the Nth information calculated based on the detection signal output between the imaging corresponding to the Nth image and the imaging corresponding to the (N + 1)th image, and the (N - 1)th information calculated one before the Nth information, according to a predetermined condition regarding the time required for the calculation based on the detection signal; A determination step of determining the imaging timing corresponding to the (N + 1)-th image based on the selected N-th information or the (N - 1)-th information having The predetermined condition is information regarding whether the calculation of the N-th information is completed by the time of determining the imaging timing corresponding to the (N + 1)-th image, In the selection step, when it is determined that the calculation of the N-th information is completed, the N-th information is selected, and when it is determined that the calculation of the N-th information is not completed, the (N - 1)-th information is selected. A control method for an electronic device characterized by this.

21. While controlling an image sensor to repeatedly image a subject to acquire images, after imaging for acquiring the N-th image (N is a natural number), until imaging for acquiring the (N + 1)-th image is performed, a control step of controlling the image sensor to output a detection signal for detecting flicker; An arithmetic step of calculating information regarding flicker based on the detection signal; According to a predetermined condition regarding the time required for the calculation based on the detection signal, between imaging corresponding to the N-th image and performing imaging corresponding to the (N + 1)-th image, the N-th information calculated based on the detection signal output during this period and either the (N - 1)-th information calculated one before the N-th information are selected. A selection step; A determination step of determining the imaging timing corresponding to the (N + 1)-th image based on the selected N-th information or the (N - 1)-th information having The predetermined condition is information regarding the frequency of imaging the subject to acquire the image, In the selection step, in the case of a first frequency, the N-th information is selected, and in the case of a second frequency higher than the first frequency, the (N - 1)-th information is selected. A control method for an electronic device characterized by this.

22. While controlling an image sensor to repeatedly image a subject to acquire images, between the exposure of the first still image and the exposure of the second still image, a control step of controlling the image sensor to output a detection signal for detecting flicker; An arithmetic step of calculating information regarding flicker based on the detection signal; A determination step of determining a shooting timing in the exposure of the second still image based on either first information regarding flicker calculated between the exposure of the first still image and the exposure of the second still image, and second information regarding flicker calculated before the first information is calculated, In the determination step, when the calculation of the first information is completed by the time of determining the shooting timing of the exposure of the second still image, the first information is selected, and if the calculation of the first information is not completed, the second information is selected. A control method for an electronic device characterized by this.

23. A control step of controlling an image sensor to repeatedly image a subject to obtain an image, and controlling the image sensor to output a detection signal for detecting flicker between the exposure of the first frame of the moving image and the exposure of the second frame of the moving image, An arithmetic step of calculating information regarding flicker based on the detection signal, A determination step of determining a shooting timing in the exposure of the second frame of the moving image based on either first information regarding flicker calculated between the exposure of the first frame of the moving image and the exposure of the second frame of the moving image, and second information regarding flicker calculated before the first information is calculated, In the determination step, when the calculation of the first information is completed by the time of determining the shooting timing of the exposure of the second frame of the moving image, the first information is selected, and if the calculation of the first information is not completed, the second information is selected. A control method for an electronic device characterized by this.

24. A control step of controlling an image sensor to repeatedly image a subject to obtain an image, and controlling the image sensor to output a detection signal for detecting flicker between the exposure of the first still image and the exposure of the second still image, An arithmetic step of calculating information regarding flicker based on the detection signal, A determination step of determining a shooting timing in the exposure of the second still image based on either first information regarding flicker calculated between the exposure of the first still image and the exposure of the second still image, and second information regarding flicker calculated before the first information is calculated, In the determination step, either the first information or the second information used to determine the shooting timing in the exposure of the second still image is selected based on information regarding the frequency of repeatedly imaging a subject to capture still images. A method for controlling an electronic device, comprising: selecting the first information when the frequency is a first frequency, and selecting the second information when the frequency is a second frequency higher than the first frequency.

25. A control step of controlling an image sensor to repeatedly image a subject to acquire an image, and controlling the image sensor to output a detection signal for detecting flicker between the exposure of a first frame of a moving image and the exposure of a second frame of the moving image; An arithmetic step of calculating information regarding flicker based on the detection signal; A determination step of determining the shooting timing in the exposure of the second frame of the moving image based on either first information regarding flicker calculated between the exposure of the first frame of the moving image and the exposure of the second frame of the moving image, and second information regarding flicker calculated before the first information is calculated. In the determination step, either the first information or the second information used to determine the shooting timing in the exposure of the second frame of the moving image is selected based on a frame rate, which is information regarding the frequency of acquiring frames of the moving image. A method for controlling an electronic device, comprising: selecting the first information when the frame rate is lower than a predetermined threshold, and selecting the second information when the frame rate is equal to or higher than the predetermined threshold.

26. A program for causing a computer to function as each means of the electronic device according to any one of claims 1 to 19.

27. A computer-readable storage medium storing the program according to claim 26.

Images