Imaging device, control method thereof, program, and storage medium

Abstract

To provide an image capturing apparatus capable of acquiring images of good quality with reduced effects of a flicker even during continuous capturing and moving image capturing.SOLUTION: Included are: an image capturing unit configured to convert light from an object into an electrical signal; a flicker detection unit configured to detect a flicker of a light source using an image from the image capturing unit; and a control unit for concurrent execution of a first image capturing operation in which the image capturing unit is caused to periodically capture an image for storage and a second image capturing operation in which the image capturing unit is caused to periodically capture an image for display. The control unit: in the first image capturing operation, causes the image capturing unit to perform capturing in accordance with peak timing of a flicker that has been detected by the flicker detection unit; and in a case where an accumulation period of the image capturing unit in the first image capturing operation and an accumulation period of the image capturing unit in the second image capturing operation overlap, changes timing of capturing by the image capturing unit in the second image capturing operation.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to an imaging device. [Background technology]

[0002] In recent years, imaging devices such as home video cameras and digital still cameras have become widespread. These imaging devices have functions such as continuous shooting and video shooting, improving the convenience of users when it comes to shooting. In addition, a mode is provided in which shooting is done only by slit rolling readout of the image sensor without using a mechanical shutter, which has the advantage of enabling faster continuous shooting speeds than shooting with a mechanical shutter.

[0003] If flicker is present in the light source when shooting in these continuous shooting or video shooting modes, striped noise appears in the image, degrading the image quality.

[0004] Regarding this flicker phenomenon, Patent Document 1 discloses a technique for reducing the effect of flicker by synthesizing images with limited accumulation times. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2017-143404 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, while the technique disclosed in Patent Document 1 can reduce the effect of flicker, it has the problem of reducing the degree of freedom in the accumulation time. In addition, there is also the problem that image quality deteriorates due to image synthesis.

[0007] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide an imaging device that can obtain images of good image quality with reduced effects of flicker, even during continuous shooting or video shooting. [Means for solving the problem]

[0008] An imaging device according to the present invention comprises imaging means for converting light from a subject into an electrical signal, flicker detection means for detecting flicker of a light source using the electrical signal, and control means for causing the imaging means to execute in parallel a first imaging operation for periodically capturing images for recording and a second imaging operation for periodically capturing images for display, wherein the control means, in the first imaging operation, causes the imaging means to capture images for recording at a timing corresponding to a peak timing of the flicker detected by the flicker detection means, and, when an accumulation time of the imaging means in the first imaging operation overlaps with an accumulation time of the imaging means in the second imaging operation, controls the imaging means to capture images for display at a timing corresponding to a peak timing of the flicker detected by the flicker detection means, and controls the imaging means to capture images for display at a timing corresponding to a peak timing of the flicker detected by the flicker detection means. And, The present invention is characterized in that the timing at which the image pickup means picks up an image for display is controlled to be changed. Effect of the Invention

[0009] According to the present invention, it is possible to obtain images of good quality with reduced effects of flicker even during continuous shooting or video shooting. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram showing the configuration of a digital camera as an embodiment of an imaging apparatus of the present invention. [Diagram 2] 4 is a flowchart showing an image capturing operation of a digital camera according to an embodiment. [Diagram 3] 11 is a graph showing the relationship between accumulation control and output photometric value when flicker is present. [Figure 4] FIG. 4 is a diagram for explaining an example of a method for calculating a peak position of a flicker. [Diagram 5] FIG. 13 is a diagram showing shooting timed to coincide with the peak timing of flicker. [Figure 6] A diagram showing the timing of capturing still images and live view images (LV). [Figure 7] 4A and 4B are diagrams showing timing adjustment of capturing and displaying a live view image. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0012] FIG. 1 is a diagram showing the configuration of a digital camera 100 which is an embodiment of an imaging apparatus of the present invention.

[0013] 1, a digital camera 100 includes a photographing lens 10, a mechanical shutter 12 with an aperture function, an image sensor 14 that converts an optical image into an electrical signal, and an A / D converter 16 that converts an analog output signal of the image sensor 14 into a digital signal. Here, the A / D converter 16 may be built into the image sensor 14.

[0014] The timing generation circuit 18 is a circuit that supplies clock signals and control signals to the image sensor 14 and the A / D converter 16, and is controlled by the memory control circuit 22 and the system control circuit 50. Note that the control of the accumulation time of the image sensor 14 is usually performed by the mechanical shutter 12, but it can also be achieved by a method other than using the mechanical shutter 12. In other words, it is possible to control the accumulation time by an electronic shutter realized by controlling the reset timing of the image sensor 14, and this can be used for video shooting, etc.

[0015] The image processing circuit 20 performs predetermined pixel interpolation processing and color conversion processing on the data from the A / D converter 16 or the data from the memory control circuit 22. In addition, the image processing circuit 20 performs image cropping and magnification processing, thereby realizing an electronic zoom function.

[0016] In addition, the image processing circuit 20 performs a predetermined calculation process using the captured image data, and based on the obtained calculation results, the system control circuit 50 controls the exposure control circuit 40 and the distance measurement control circuit 42 to perform TTL AF processing, AE processing, and EF processing.

[0017] The memory control circuit 22 controls the A / D converter 16, the timing generation circuit 18, the image processing circuit 20, the memory 30, and the compression / expansion circuit 32. Data from the A / D converter 16 is written into the memory 30 via the image processing circuit 20 and the memory control circuit 22, or data from the A / D converter 16 is written directly into the memory control circuit 22.

[0018] The image display unit 28 is composed of a TFT LCD or the like, and the image data for display written in the memory 30 is displayed by the image display unit 28 via the memory control circuit 22. If the captured image data is displayed sequentially using the image display unit 28, it is possible to realize an electronic viewfinder function. Also, the image display unit 28 can arbitrarily turn the display ON / OFF according to instructions from the system control circuit 50, and when the display is turned OFF, the power consumption of the digital camera 100 can be significantly reduced.

[0019] The memory 30 is a storage unit for storing captured still images and moving images, and has a storage capacity sufficient to store a predetermined number of still images and a predetermined length of moving images. This makes it possible to write a large amount of images to the memory 30 at high speed even in the case of continuous shooting in which a plurality of still images are continuously shot or panoramic shooting. The memory 30 can also be used as a working area for the system control circuit 50.

[0020] The non-volatile memory 31 is a storage unit configured with a Flash ROM or the like. The program code executed by the system control circuit 50 is stored in the non-volatile memory 31, and is sequentially read and executed. In addition, the non-volatile memory 31 has an area for storing system information and an area for storing user setting information, and various information and settings can be read and restored at the next startup.

[0021] The compression / expansion circuit 32 is a circuit that compresses and expands image data using adaptive discrete cosine transform (ADCT) or the like. It reads images stored in the memory 30, performs compression or expansion processing on the images, and writes the processed data back to the memory 30.

[0022] The exposure control circuit 40 is a circuit that controls the shutter 12 having an aperture function, and also has a flash light adjustment function by linking with a flash 48. The distance measurement control circuit 42 controls the focusing of the photographic lens 10, and the zoom control circuit 44 controls the zooming of the photographic lens 10.

[0023] The flash 48 also has an AF assist light projection function and a flash dimming function. The exposure control circuit 40 and the distance measurement control circuit 42 perform exposure control and distance measurement control using the TTL method. The system control circuit 50 controls the exposure control circuit 40 and the distance measurement control circuit 42 based on the results of calculations performed by the image processing circuit 20 on captured image data. The system control circuit 50 controls the entire digital camera 100.

[0024] The operating members 60, 62, 64, 66, 70, 72 are operating means for inputting various operational instructions of the system control circuit 50, and are composed of one or a combination of a switch, a dial, a touch panel, pointing by line of sight detection, a voice recognition device, etc. Here, these operating means will be specifically described.

[0025] The mode dial switch 60 can be used to switch between various function modes, such as power off, automatic shooting mode, shooting mode, panoramic shooting mode, video shooting mode, playback mode, and PC connection mode.

[0026] A shutter switch 62 (SW1) is turned on during operation of the shutter button, and instructs the start of operations such as AF (autofocus) processing, AE (auto exposure) processing, and AWB (auto white balance) processing.

[0027] The shutter switch 64 (SW2) is turned on when the shutter button is operated. In the case of flash photography, after EF (flash pre-emission) processing is performed, the image sensor 14 is exposed for the exposure time determined by the AE processing. The flash is emitted during this exposure period, and at the same time as the exposure period ends, the exposure control circuit 40 closes the shutter 12 to block light, thereby ending the exposure of the image sensor 14.

[0028] The shutter switch 64 (SW2) instructs the start of a series of processes, including a read process in which the signal read out from the image sensor 14 is written as image data in memory 30 via the A / D converter 16 and memory control circuit 22, a development process using calculations in the image processing circuit 20 and memory control circuit 22, and a recording process in which the image data is read out from memory 30, compressed in the compression / expansion circuit 32, and written to the recording medium 200.

[0029] The display changeover switch 66 changes the display state of the image display unit 28. This function makes it possible to reduce power consumption by cutting off the current supply to the image display unit, which is made up of a TFT LCD or the like, when taking a picture using the optical viewfinder 104.

[0030] The operation unit 70 is made up of various buttons, a touch panel, a rotary dial, etc., and is equipped with a menu button, a set button, a macro button, a multi-screen playback page break button, a flash setting button, a single shot / continuous shooting / self-timer switching button, etc. It also is equipped with a menu movement + (plus) button, menu movement - (minus) button, playback image movement + (plus) button, playback image movement - (minus) button, a shooting image quality selection button, an exposure compensation button, a date / time setting button, etc.

[0031] The zoom switch 72 functions as a zoom operation means by which the user instructs a change in the magnification of the captured image. This zoom switch 72 consists of a telephoto switch for changing the imaging angle of view to the telephoto side, and a wide switch for changing the imaging angle of view to the wide-angle side. By using this zoom switch 72, it is possible to instruct the zoom control circuit 44 to change the imaging angle of view of the photographing lens 10, thereby performing optical zoom operation. In addition, it is also possible to perform image cropping by the image processing circuit 20, electronic zooming changes of the imaging angle of view by pixel interpolation processing, etc.

[0032] The thermistor 74 measures the temperature inside the camera. Since defective pixels in the image sensor 14 are affected by temperature, it is necessary to change the defect correction process depending on the temperature at the time of shooting. The thermistor is placed near the image sensor 14 inside the digital camera 100 and measures the temperature of the image sensor 14 itself.

[0033] The interface 90 is an interface with a recording unit 200 that includes a recording medium 202 such as a memory card or a hard disk, and the connector 92 is a connector that connects to the recording medium 202 .

[0034] Barrier 102 is a protective means for preventing the imaging section, including lens 10, from becoming dirty or damaged by covering the imaging section of digital camera 100. Optical viewfinder 104 enables the photographer to observe the subject without using the electronic viewfinder function of image display unit 28, and allows the photographer to take pictures using only optical viewfinder 104.

[0035] The communication unit 110 has various communication functions such as USB, IEEE1394, LAN, wireless communication, etc. The connector 112 is a connector that connects the digital camera 100 to other devices via the communication unit 110, or an antenna in the case of wireless communication.

[0036] The recording unit 200 performs recording using a recording medium 202 such as a memory card or a hard disk. The recording unit 200 includes the recording medium 202 configured from a semiconductor memory, a magnetic disk, or the like, an interface 204 for connecting to the digital camera 100, and a connector 206 for connecting to the digital camera 100.

[0037] FIG. 2 is a flowchart showing the imaging operation of the digital camera 100 in this embodiment.

[0038] When shooting starts, in step S101, the system control circuit 50 detects whether or not flicker occurs in the light source, and if flicker occurs, detects the peak time of the flicker. This flicker detection will be described later with reference to Figures 3 and 4.

[0039] In step S102, the system control circuit 50 captures images at a timing that allows flicker to be reduced, based on the flicker detection result in step S101. This flicker reduction capture will be described later with reference to FIG.

[0040] In step S103, the system control circuit 50 displays a live view image in accordance with the display timing. The operation of displaying a live view image in accordance with the display timing will be described later with reference to FIG.

[0041] In step S104, the system control circuit 50 determines whether or not to continue shooting, and if the photographer has instructed to continue shooting, the process returns to step S101, and if the photographer has instructed to end shooting, the system control circuit 50 ends shooting.

[0042] FIG. 3 is a diagram showing the relationship between accumulation control and output photometric value when flicker is present.

[0043] In Figure 3, when the commercial power supply has a frequency of 50 Hz, the nth accumulation for detecting flicker is designated as "accumulation n", the readout of the result of accumulation n is designated as "readout n", and the photometric value obtained from the result of readout n is designated as "AE(n)". In addition, since accumulation is performed for a finite period of time, the acquisition time of each photometric value is represented by the median value during the accumulation period, and the time when the photometric value AE(n) is acquired is designated as "t(n)". Note that while Figure 3 only shows plots for n=1 and n=2, the same applies to plots for n=3 to 12.

[0044] If we assume that one accumulation time for detecting flicker is 1.66 msec, then when the light source frequency is 50 Hz, the flicker emission cycle is 10 ms, and 10÷1.66 ≒ 6. Therefore, as shown in Figure 3, the same photometric value is obtained in six cycles regardless of the accumulation timing. In other words, the relationship is AE(n) = AE(n+6).

[0045] Similarly, when the light source frequency is 60 Hz, the flicker emission period is 8.33 ms, and 8.33 / 1.66 ≒ 5. Therefore, the same photometric value is obtained in five periods, and the relationship is AE(n) = AE(n + 5). On the other hand, in an environment where flicker does not exist, AE(n) is constant regardless of n. From the above, by defining the evaluation values ​​F50 and F60 using formulas (1) and (2), respectively, and comparing them with the threshold value Fth, it is possible to determine whether or not flicker exists, and if so, the frequency (light emission period) of the flicker.

[0046]

number

[0047] That is, when F50 < Fth and F60 < Fth are satisfied, it can be determined that the environment is free of flicker. Also, when F50 < Fth and F60 ≥ Fth are satisfied, it can be determined that the environment is a flicker environment with a light emission period T = 10 ms (light source frequency 50 Hz). Furthermore, when F50 ≥ Fth and F60 < Fth are satisfied, it can be determined that the environment is a flicker environment with a light emission period T = 8.33 ms (light source frequency 60 Hz). Also, it is conceivable that both F50 and F60 exceed Fth due to panning or the subject moving. In this case, the magnitudes of F50 and F60 are compared. If F50 is smaller, it is determined that the environment is a flicker environment with a light emission period T = 10 ms (light source frequency 50 Hz). If F60 is smaller, it is determined that the environment is a flicker environment with a light emission period T = 8.33 ms (light source frequency 60 Hz). That is, when F50 ≥ Fth and F60 ≥ Fth are satisfied, if F50 ≤ F60, it is determined that the environment is a flicker environment with a light emission period T = 10 ms (light source frequency 50 Hz). If F50 > F60, it is determined that the environment is a flicker environment with a light emission period T = 8.33 ms (light source frequency 60 Hz).

[0048] In this way, by calculating the evaluation values F50 and F60, it is possible to determine whether there is flicker in the shooting environment. If there is, what is the light source frequency, whether it is 50 Hz or 60 Hz, and further calculate the light emission period T at that time. And when there is flicker, a synchronization signal at the peak position of the flicker light amount is generated. Basically, the obtained 12 photometric values are interpolated to calculate the time t(peak) when the peak of the flicker is taken.

[0049] FIG. 4 is a diagram for explaining an example of a method for calculating the peak position of flicker. In FIG. 4(a), the point that obtains the maximum output among AE(1) to AE(12) is set as P2(t(m), AE(m)), the point of the photometric result one before that is set as P1(t(m - 1), AE(m - 1)), and the point of the photometric result one after that is set as P3(t(m + 1), AE(m + 1)). First, a line passing through two points, the point where the smaller of AE(m-1) and AE(m+1) is found (P3 in the example in Figure 4(a)) and point P2, is determined as L1 = at + b. Additionally, a line passing through the point where the larger of AE(m-1) and AE(m+1) is found (P1 in the example in Figure 4(a)) with a slope of -a is determined as L2. Then, by finding the intersection of line L1 and line L2, the time t(peak) of the peak position and the photometric value AE(peak) at the peak can be calculated.

[0050] In addition, since the light emission cycle T of the flicker is also known, a peak synchronization signal is generated that generates a pulse at every timing t=t(peak)+nT (n is a natural number) as shown in Fig. 4(b). As described above, if flicker is present, the light emission cycle, peak photometric value, and peak synchronization signal are generated. 5 is a diagram showing the operation of capturing a still image at a timing that matches the peak position (peak time) of the flicker. In this embodiment, the still image is captured using the electronic shutter function of the image sensor 14.

[0051] When the peak position (peak time) t(peak) of the flicker is detected, the timing of capturing a still image is adjusted to match the timing of the capture instruction. First, in Fig. 5, it is determined whether capturing is possible at time t(peak)+T, which is immediately after the capture instruction. In the example of Fig. 5, if accumulation is not started before the capture instruction time Tcap, the accumulation center cannot be aligned with time t(peak)+T. Therefore, it is determined that capturing at time t(peak)+T is not possible.

[0052] Next, at time t(peak)+2T, since the accumulation start time Tst can be set after the imaging instruction time Tcap, it is determined that imaging is possible at time t(peak)+2T.

[0053] To capture a still image at time t(peak)+2T, the VD size VDT, which is the time from the shooting command time Tcap to the timing of generation of the vertical synchronization signal VD, and the time Tesh (electronic shutter period), which is the time from the shooting command time Tcap to the reset start time Tst by the electronic shutter that starts accumulating a still image, are set. This makes it possible to capture a still image with the accumulation center at time t(peak)+2T. These time and duration values ​​are calculated by the following formula, where the shooting command time is Tcap, the flicker peak time is Tp, the accumulation start time is Tst, the accumulation time is Texp, and the readout time is Trd.

[0054] Accumulation start time = Flicker peak time - (Readout time + Accumulation time) / 2 Tst=Tp -(Trd+Texp) / 2 Electronic shutter period = accumulation start time - shooting instruction time Tesh=Tst-Tcap VD size = electronic shutter period + accumulation time VDT=Tesh+Texp FIG. 6 is a diagram showing the capture timing of a still image (image for recording) and a live view image (image for display).

[0055] Still image 1 is captured to coincide with the flicker peak, and live view image 1 (LV1) is captured to coincide with the display timing immediately afterwards. Still image 2 and live view image 2 (LV2) are captured in the same way. For still image 3, the accumulation time of still image 3 and the live view image (LV3) in the next display cycle overlap, so the live view image cannot be accumulated at this timing. Therefore, the shooting position (shooting timing) of the live view image (LV3) is shifted until the next display cycle. To achieve this, the cycle of the vertical synchronization signal for the live view image (LV3) is extended (delayed) to adjust the shooting position (shooting timing).

[0056] Still images are shot in accordance with the peak timing of the flicker, so the effects of flicker can be reduced, but live view images must be shot in accordance with the display timing, so the effects of flicker can be reduced by adjusting the accumulation time of the live view image. The accumulation time of the live view image is set to an integer multiple of the flicker cycle. Specifically, if the light source frequency is 50Hz, the accumulation time of the live view is set to 1 / 50sec or 1 / 100sec, and if the light source frequency is 60Hz, the accumulation time of the live view is set to 1 / 60sec or 1 / 120sec.

[0057] By capturing images and storing and displaying live view images in the above manner, it is possible to obtain images with good image quality with reduced flicker effects even during continuous shooting or video shooting. Also, as shown in Fig. 6, by periodically repeating in parallel a first imaging operation which is a continuous shooting operation (operation for continuously shooting) of still images and a second imaging operation which stores and displays live view images, it is possible to improve the continuous shooting speed of still images compared to the case where shooting is performed while switching between the first imaging operation and the second imaging operation.

[0058] FIG. 7 is a diagram showing timing adjustment of capturing and displaying a live view image.

[0059] Although the capture cycle and display cycle of the live view image are roughly the same, the image sensor drive clock and the camera drive clock are independent clocks and may have minute errors, and if the errors accumulate over a long period of time, the lag between the capture and display of the live view image may increase. To keep this lag within a specified range, it is necessary to periodically align the capture and display timing of the live view image.

[0060] This timing adjustment is performed by detecting the difference between the imaging synchronization signal VD and the display synchronization signal VD of the live view image and adjusting the frame size of the live view image. Specifically, the time when the imaging synchronization signal VD falls and the time when the display synchronization signal VD falls are measured, and when the difference between the two becomes a predetermined value or more, the frame size of the next live view image is added or subtracted. The electronic shutter period of the image sensor is also adjusted accordingly. This operation allows a natural live view image to be displayed.

[0061] (Other embodiments) The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

[0062] The invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0063] 10: photographing lens, 12: shutter, 14: image sensor, 16: A / D converter, 18: timing generation circuit, 20: image processing circuit, 22: memory control circuit, 28: image display unit, 30: memory, 32: image compression / expansion circuit, 40: exposure control circuit, 42: distance measurement control circuit, 44: zoom control circuit, 48: flash, 50: system control circuit

Claims

1. An imaging means for converting light from a subject into an electrical signal; a flicker detection means for detecting flicker of a light source using the electrical signal; a control means for causing the imaging means to execute, in parallel, a first imaging operation for periodically capturing an image for recording and a second imaging operation for periodically capturing an image for display by the imaging means; the control means controls the imaging means to capture an image for recording at a timing corresponding to a peak timing of the flicker detected by the flicker detection means, during the first imaging operation, and when an accumulation time of the imaging means in the first imaging operation overlaps with an accumulation time of the imaging means in the second imaging operation, to change the timing at which the imaging means captures an image for display, during the second imaging operation.

2. 2. The imaging apparatus according to claim 1, wherein the first imaging operation is an operation for continuously capturing still images.

3. 2. The imaging apparatus according to claim 1, wherein the first imaging operation is an operation for capturing a moving image.

4. 4. The imaging apparatus according to claim 2, wherein the second imaging operation is an operation of capturing a live view image.

5. 5. The imaging apparatus according to claim 4, wherein the control means causes the imaging means to capture images for display in accordance with a display cycle of a live view.

6. 6. The imaging device according to claim 1, wherein the control means controls to delay a timing at which the imaging means captures an image for display in the second imaging operation when an accumulation time of the imaging means in the first imaging operation overlaps with an accumulation time of the imaging means in the second imaging operation.

7. 7. The imaging device according to claim 6, wherein the control means controls so as to delay, in the second imaging operation, the timing of capturing an image for display by the imaging means until the next display cycle when an accumulation time of the imaging means in the first imaging operation overlaps with an accumulation time of the imaging means in the second imaging operation.

8. 8. The imaging device according to claim 1, wherein the control means controls a timing at which the imaging means captures an image for recording so that a center of an accumulation time of the imaging means in the first imaging operation coincides with a peak timing of the flicker.

9. The imaging device according to any one of claims 1 to 8, characterized in that the control means changes the timing at which the imaging means captures an image for display in the second imaging operation by adjusting a vertical synchronization signal and using an electronic shutter function.

10. 10. The imaging device according to claim 1, further comprising a detection unit that detects a shift between a period for capturing an image for display in the second imaging operation and a period for displaying the captured image.

11. The imaging device according to claim 10, wherein the control means corrects a difference between a period for capturing an image for display in the second imaging operation and a period for displaying the captured image based on a detection result by the detection means.

12. 12. The imaging device according to claim 1, wherein the control means, in the second imaging operation, causes the imaging means to capture an image for display with an accumulation time that is an integer multiple of the period of the flicker detected by the flicker detection means.

13. A method for controlling an imaging device having an imaging unit that converts light from a subject into an electrical signal, comprising the steps of: a flicker detection step of detecting flicker of a light source using the electrical signal; a control step of causing the imaging means to execute, in parallel, a first imaging operation for periodically capturing an image for recording and a second imaging operation for periodically capturing an image for display by the imaging means; A control method for an imaging device, characterized in that, in the control step, in the first imaging operation, the imaging means is caused to capture an image for recording at a timing corresponding to a peak timing of the flicker detected in the flicker detection step, and when an accumulation time of the imaging means in the first imaging operation overlaps with an accumulation time of the imaging means in the second imaging operation, the timing at which the imaging means captures an image for display is changed in the second imaging operation.

14. A program for causing a computer to execute each step of the control method according to claim 13.

15. A computer-readable storage medium storing a program for causing a computer to execute each step of the control method according to claim 13.

Images