Image capturing apparatus, control method, and storage medium

Abstract

To provide an imaging apparatus capable of suppressing a sense of incongruity due to a difference in image magnification in a mode for automatically switching between use and nonuse of an image composition function.SOLUTION: The imaging apparatus includes an acquisition unit that acquires information regarding selection of a mode for automatically switching between use and non-use of a function of combining a plurality of images to generate one image, and a control unit that controls an image magnification, and the control unit makes a method of controlling the image magnification different between a case where the mode is selected and a case where the mode is not selected.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an imaging device, a control method, and a program. [Background technology]

[0002] Conventionally, in photographing devices such as cameras equipped with an image sensor, a technology has been known in which multiple images acquired in a short period of time are aligned and combined to obtain an image equivalent to a long exposure without camera shake (hereinafter referred to as image synthesis anti-shake) (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4418632 Summary of the Invention [Problem to be solved by the invention]

[0004] In image synthesis vibration reduction, the outer periphery of the captured image may be deleted because alignment is performed during synthesis, and the image magnification may differ between shooting using image synthesis vibration reduction and normal shooting without it. Some imaging devices have a mode that automatically switches between using and not using image synthesis vibration reduction, but in this case, there is a risk that photos with different image magnifications will be taken each time they are taken.

[0005] The present invention aims to provide an imaging device that can suppress the sense of incongruity caused by differences in image magnification in a mode that automatically switches between using and not using an image synthesis function. [Means for solving the problem]

[0006] An imaging device according to one aspect of the present invention is an imaging device capable of capturing multiple images by continuous shooting, and includes an acquisition unit that acquires information regarding the selection of a mode that automatically switches between using and not using a function for combining multiple images to generate a single image, and a control unit that controls image magnification, and the control unit is characterized in that it controls the image magnification in a different manner depending on whether a mode is selected or not. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an imaging device that can suppress the sense of incongruity caused by differences in image magnification in a mode that automatically switches between using and not using an image synthesis function. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is an explanatory diagram of an imaging device according to an embodiment of the present invention. [Figure 2] FIG. 10 is a diagram showing an image acquired by photographing using image synthesis image stabilization. [Figure 3] FIG. 10 is a diagram showing an example of an image output when a group photo is taken with the automatic mode selected. [Figure 4] 10 is a flowchart showing a control process for image magnification according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same components, and redundant explanations will be omitted.

[0010] 1A and 1B are explanatory diagrams of a digital camera as an example of an imaging device according to an embodiment of the present invention, in which Fig. 1A is a block diagram of the digital camera, and Fig. 1B is a central cross-sectional view of the digital camera.

[0011] The digital camera has a camera body 1 and an interchangeable lens 3, and is configured to be able to capture multiple images by continuously shooting with a single shooting command. The camera body 1 and the interchangeable lens 3 can exchange electrical signals via the electrically connected lens contacts 20.

[0012] The camera body 1 includes a camera system control unit 10, an image sensor 11, an image processing unit 12, a memory unit 13, a focal plane shutter (hereinafter, shutter) 14, an operation unit 15, a display unit 16, a viewfinder optical system 21, and a speaker 22. The camera system control unit 10 includes a CPU (Central Processing Unit) and other components, and controls the camera body 1, including communication with the interchangeable lens 3. The camera system control unit 10 also includes a shake correction control unit 10a, an image synthesis control unit 10b, an acquisition unit 10c, and an image magnification control unit (control unit) 10d. The acquisition unit 10c acquires information regarding the selection of a mode that automatically switches between using (enabled) and not using (disabled) a function that synthesizes multiple images to generate a single image. In this embodiment, the acquisition unit 10c acquires information regarding the selection of an automatic mode, which will be described later. The control unit 10d controls the image magnification. The image sensor 11 photoelectrically converts a subject image formed by the photographing optical system 32 of the interchangeable lens 3. The analog electrical signal output from the image sensor 11 is converted into a digital electrical signal (image signal) by an A / D converter (not shown). The image processing unit 12, which includes a white balance circuit, a gamma correction circuit, an interpolation circuit, and the like, performs various image processing on the digital electrical signal to generate image data. The memory unit 13 records information such as the image data generated by the image processing unit 12. The shutter 14 includes a shutter curtain consisting of a front curtain and a rear curtain, and controls the blocking and passage of light from the photographing optical system 32 to the image sensor 11 by moving the shutter curtain within an opening. The operation unit 15 recognizes user operations. The display unit 16 displays images and the like. The display unit 16 includes a rear LCD unit 16a provided on the rear of the camera body 1 and a viewfinder display unit 16b arranged in the viewfinder optical system 21 and visible through the eyepiece 21a. The user can freely switch between the rear LCD unit 16a and the viewfinder display unit 16b. The speaker 22 reproduces operation sounds for settings, shutter sounds when taking pictures, and the like as needed.

[0013] Camera body 1 also has camera-side shake correction means 17 and gyro sensor 18. Camera-side shake correction means 17 shifts image sensor 11 in a direction that includes a component that is approximately perpendicular to optical axis 31 of photographing optical system 32, and rotates image sensor 11 around an axis that is approximately parallel to optical axis 31. Gyro sensor 18 is an angular shake sensor that detects the angular velocity of rotation around each of the X, Y, and Z axes of camera body 1. Gyro sensor 18 may be configured in a single package. Alternatively, three identical packages may be installed in each axial direction.

[0014] The interchangeable lens 3 has a lens system control unit 30, a photographing optical system 32, a focus drive unit 33, and a lens side shake correction unit 34. The lens system control unit 30 controls the interchangeable lens 3. The focus drive unit 33 moves a focus lens included in the photographing optical system 32. The lens side shake correction unit 34 shifts a shift lens included in the photographing optical system 32 in a direction that includes a component in a direction approximately perpendicular to the optical axis 31.

[0015] The camera system control unit 10 generates timing signals and outputs them to various components when capturing an image. When the release button included in the operation unit 15 is pressed and an operation instruction is received, the camera system control unit 10 controls the image sensor 11 in accordance with the instruction and transmits a command signal to the lens system control unit 30. The release button can detect a first depression, known as a halfway press, and a second depression, known as a full press. When the release button detects a halfway press, the camera system control unit 10 issues a command to perform a preparatory operation for capturing an image, such as an autofocus (AF) operation. When the release button detects a full press, the camera system control unit 10 activates the shutter 14 to initiate an exposure operation for capturing a still image. Depending on the settings, pressing the release button once can also perform multiple exposure operations for capturing a still image in succession.

[0016] Camera shake correction will be described below. First, camera-side shake correction means 17 will be described. Shake correction control unit 10a calculates the angular shake component of camera body 1 by performing filtering and integration processing on the angular velocity detected by gyro sensor 18, and generates a drive signal for camera-side shake correction means 17. Camera-side shake correction means 17 uses the drive signal to correct camera shake by shifting image sensor 11 in a direction that includes a component in a direction approximately perpendicular to optical axis 31, and by rotating image sensor 11 around an axis approximately parallel to optical axis 31. Shifting image sensor 11 corrects rotational shake of camera body 1 in the pitch and yaw directions, and rotating image sensor 11 around an axis approximately parallel to optical axis 31 corrects roll shake of camera body 1.

[0017] Similarly, lens-side vibration compensation means 34 is driven by receiving the drive signal generated by vibration compensation control unit 10a via lens contact 20 and lens system control unit 30. Lens-side vibration compensation means 34 shifts the shift lens in a direction that includes a component in a direction approximately perpendicular to optical axis 31, thereby compensating for rotational vibration of camera body 1 in the pitch and yaw directions.

[0018] Image synthesis stabilization is explained below. A commonly known method for taking suitable photographs in environments with insufficient light is to extend the exposure time (hereinafter referred to as "long-exposure photography"). However, the longer the exposure time, the greater the effect of camera shake, which may not be fully compensated for by the aforementioned camera shake correction operation, resulting in a photograph with significant blur. Image processing unit 12 synthesizes multiple images output by imaging element 11 while aligning the images in time series (hereinafter referred to as "image synthesis stabilization"), thereby generating a single image with reduced blur. Image processing unit 12 aligns the images by translational movement with two-pixel accuracy using the motion vectors between the images. The image synthesized by image processing unit 12 is recorded in memory unit 13. When performing image synthesis stabilization, a predetermined number of photographs are continuously captured when the user presses the release button included in operation unit 15 once.

[0019] Furthermore, when performing image synthesis stabilization, the exposure time is divided to be the same as that of long-exposure photography. For example, in the case of long-exposure photography with an exposure time of 1 second, by aligning and compositing 10 consecutive images taken with an exposure time of 1 / 10 second, an image with exposure equivalent to that of long-exposure photography and reduced blur can be obtained. However, when performing image synthesis stabilization, it is cumbersome for the user to set the exposure time per image, the number of images to be taken, etc., each time. In this embodiment, the image synthesis control unit 10b automatically determines the appropriate settings, and image synthesis stabilization can be used for photography. In this embodiment, the camera system control unit 10 can also be set to a mode (hereinafter referred to as automatic mode) in which the camera system control unit 10 automatically determines whether to use image synthesis stabilization for photography (automatically switches between using and not using the image synthesis stabilization function).

[0020] The difference in image magnification between normal photography and photography using image synthesis vibration reduction will be described below with reference to FIG. 2. FIG. 2 is a diagram showing an image acquired by photography using image synthesis vibration reduction. In FIG. 2, an example will be described in which two images are combined. FIG. 2(a) is the first image acquired by photography using image synthesis vibration reduction. FIG. 2(b) is the second image acquired by photography using image synthesis vibration reduction. FIG. 2(c) is a diagram showing the state in which two images are being aligned and combined. FIG. 2(d) is the output image after the combination is complete.

[0021] When the user issues a shooting instruction, the first image shown in Figure 2(a) and the second image shown in Figure 2(b) are acquired. Comparing the two images, although they were taken consecutively, there is a difference in the angle of view due to factors such as camera shake by the photographer. While the difference in the angle of view is normally expected to be minute, on the order of a few pixels, this embodiment will be described assuming a large difference for ease of understanding.

[0022] When aligning and combining the first and second images, the first image is used as a reference and the second image is superimposed on top of it using a method such as additive averaging. At this time, the two images are shifted in position to be combined, so in the state of alignment and combination shown in Figure 2(c), there is an overlapping portion 2c1 of the two images, surrounded by a dashed line, and the remaining portion 2c2. After that, to make the combined image rectangular, only portion 2c1 remains and portion 2c2 is deleted. In other words, the image magnification of the combined image changes compared to the two images before combination, and the imageable area (area to be output) becomes narrower.

[0023] Problems in the automatic mode will be described below. In the automatic mode, the camera system control unit 10 automatically determines whether to use image synthesis stabilization for shooting. Specifically, in the automatic mode, the camera system control unit 10 determines whether to use image synthesis stabilization for shooting based on the relationship between a first shooting condition among the shooting conditions and a threshold value. The first shooting condition is, for example, a shooting condition under which camera shake is expected to occur, such as a shutter speed. For example, if the shutter speed is slower than the threshold value, it may be determined to use image synthesis stabilization for shooting, and if the shutter speed is faster than the threshold value, it may be determined not to use image synthesis stabilization for shooting. Here, if the first shooting condition is equal to the threshold value, shooting using image synthesis stabilization and normal shooting may be mixed, which may result in images with different image magnifications being captured each time. Note that the phrase "the first shooting condition is equal to the threshold value" refers not only to cases where the first shooting condition is exactly equal to the threshold value, but also to cases where the first shooting condition is close to the threshold value (substantially equal to the threshold value, approximately equal to the threshold value).

[0024] FIG. 3 shows an example of an image output when a group photo is taken with the automatic mode selected. When taking a group photo, continuous shooting may be performed, in which continuous shooting instructions are issued in case a subject closes their eyes. If the shooting conditions are near a threshold for determining whether to use image synthesis stabilization, the continuously captured images may include images with different image magnifications. In this case, some people may be cut off in a group photo that should include everyone, or, conversely, an area that you do not want to capture may be captured. FIG. 3 shows images captured in chronological order from left to right. The first and third images are images captured using image synthesis stabilization. The second image is an image captured using normal shooting. The first and third images captured using image synthesis stabilization have different image magnifications than the second image captured using normal shooting.

[0025] Therefore, in this embodiment, the method of controlling image magnification differs depending on whether the automatic mode is selected or not. In this embodiment, when the automatic mode is selected, the image magnification is controlled to be constant. In this embodiment, the image magnification is fixed at the image magnification when shooting using image synthesis image stabilization.

[0026] Here, the image magnification control process of this embodiment will be described with reference to Fig. 4. Fig. 4 is a flowchart showing the image magnification control process of this embodiment.

[0027] In step S41 (acquisition step), the acquisition unit 10c acquires information relating to the selection of the automatic mode.

[0028] In step S42 (control step), the control unit 10d controls the image magnification. The control unit 10d controls the image magnification differently depending on whether the automatic mode is selected or not. In this embodiment, when the automatic mode is selected, the control unit 10d controls the image magnification to be constant. For example, the image magnification may be fixed at the image magnification when shooting using image synthesis image stabilization. Furthermore, when the automatic mode is selected, the control unit 10d may perform display control so that an image corresponding to the image magnification when shooting using image synthesis image stabilization is displayed on the display unit 16 in live view. Furthermore, when the automatic mode is selected, the control unit 10d may display an image corresponding to the image magnification when shooting without using image synthesis image stabilization in live view on the display unit 16, and superimpose an index corresponding to the image magnification when shooting using image synthesis image stabilization on the image. The superimposed index may be, for example, a frame indicating the boundary of the imageable area or pointers indicating the four corners of the imageable area. Furthermore, the display form may be made different (for example, by changing the color or resolution) between the imageable area and other areas (areas outside the imageable area).

[0029] In this way, by making the image magnification when photographing without using image synthesis vibration reduction the same as the image magnification when photographing with image synthesis vibration reduction, it is possible to prevent photographs from being taken with different image magnifications each time they are photographed.

[0030] In this embodiment, an automatic mode that automatically determines whether to use image synthesis vibration reduction for shooting has been described as an example, but the present invention is not limited to this. For example, the present invention can also be applied to a mode that automatically determines whether to use a so-called HDR function that synthesizes multiple images with different exposure compensations.

[0031] As mentioned above, images captured using image synthesis image stabilization have a different image magnification than those captured during normal shooting, resulting in a narrower captureable area. Since a narrower captureable area is generally not desirable, it is preferable to make the captureable area as wide as possible. Therefore, in automatic mode, when continuous shooting is performed in which shooting instructions are issued continuously, it is preferable to control the image magnification to a constant value. A mix of consecutive images captured at the same time with different image magnifications can be unnatural to the user, but images captured at different times and with different angles of view do not cause discomfort even if the image magnifications are different. Therefore, it is preferable to not change the image magnification except during continuous shooting, as this makes it possible to prevent the captureable area from becoming narrower during normal shooting.

[0032] Furthermore, in automatic mode, it is preferable to fix the image magnification to that used when shooting using image synthesis image stabilization only when it is determined that shooting instructions have been given near the threshold for determining the effectiveness of image synthesis image stabilization. In other cases, that is, when it is determined that shooting will not involve a mixture of image synthesis image stabilization being enabled and disabled, the image magnification is not changed. This is preferable because it makes it possible to reduce the chances of the imageable area becoming narrow during normal shooting.

[0033] Furthermore, in automatic mode, it is preferable not to change the image magnification when continuous shooting is performed while the digital camera is moved significantly up, down, left, or right. Continuous shooting while moving the digital camera significantly up, down, left, or right refers to, for example, a state in which the movement amount of the digital camera per unit time during continuous shooting is greater than a predetermined amount. When image synthesis stabilization is used and not used, users often feel uncomfortable with different image magnifications when images are taken with the same angle of view. When continuous shooting is performed while the digital camera is moved significantly, the angles of view of all images are different, so even if the image magnification of all images is the same, the captured images will be different. Therefore, it is not necessary to make the image magnification when shooting without image synthesis stabilization the same as when shooting with image synthesis stabilization. As described above, the above configuration is preferable because it can reduce the chances of the captureable area becoming narrow during normal shooting.

[0034] Furthermore, as mentioned above, when continuous shooting is performed by issuing continuous shooting instructions in automatic mode, there is a risk that images with different image magnifications will be mixed together, which may cause discomfort to the user. While the method of changing the image magnification to reduce this discomfort has been described, this discomfort may also be reduced by changing the method of switching between automatic modes. In other words, when continuous shooting is performed by issuing continuous shooting instructions in automatic mode, it is possible not to switch between using and not using image synthesis vibration reduction. This makes it possible to prevent photos with different image magnifications from being taken during continuous shooting. [Other Examples] The present invention can also 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 having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0035] The disclosure of this embodiment includes the following configurations and methods. (Configuration 1) An imaging device capable of capturing multiple images by continuous shooting, an acquisition unit that acquires information regarding a selection of a mode that automatically switches between use and non-use of a function for generating one image by combining the plurality of images; a control unit that controls the image magnification; The image capturing apparatus is characterized in that the control unit controls the image magnification in a different manner depending on whether the mode is selected or not. (Configuration 2) The imaging device according to configuration 1, wherein the function is a function of generating the image with reduced camera shake by aligning and synthesizing the multiple images. (Configuration 3) 3. The imaging device according to configuration 1 or 2, wherein the control unit controls the image magnification to be constant when the mode is selected. (Configuration 4) The imaging device described in any one of configurations 1 to 3, characterized in that when the mode is selected, the control unit controls the image magnification to be the same as the image magnification when the function is used. (Configuration 5) The imaging device according to any one of configurations 1 to 4, wherein the control unit controls the image magnification to be constant when the mode is selected and continuous shooting is performed in which shooting instructions are given continuously. (Configuration 6) In the mode, it is determined whether to use the function based on a relationship between a first photographing condition among the photographing conditions and a threshold value; The imaging device described in any one of configurations 1 to 5, characterized in that the control unit does not change the image magnification when the mode is selected and the first shooting condition is the threshold value. (Configuration 7) The imaging device according to any one of configurations 1 to 6, wherein the control unit does not change the image magnification when the mode is selected and continuous shooting is performed in which shooting instructions are continuously given while the amount of movement of the imaging device per unit time is greater than a predetermined amount. (Configuration 8) The imaging device according to any one of configurations 1 to 7, wherein when the mode is selected and continuous shooting is performed in which shooting instructions are given continuously, the use and non-use of the function cannot be switched in the mode. (Configuration 9) It has a display unit, The imaging device according to any one of configurations 1 to 8, wherein when the mode is selected, the control unit causes the display unit to display a live view of an image corresponding to the image magnification when the function is used. (Configuration 10) It has a display unit, The imaging device described in any one of configurations 1 to 8, wherein when the mode is selected, the control unit causes the display unit to display a live view of an image corresponding to the image magnification when the function is not used, and superimposes an indicator on the image corresponding to the image magnification when the function is used. (Configuration 11) It has a display unit, The imaging device described in any one of configurations 1 to 8, wherein when the mode is selected, the control unit causes the display unit to display an image corresponding to the image magnification when the function is not used in a live view, and differentiates the display form between an area of ​​the image corresponding to the image magnification when the function is used and other areas. (Method 1) A control method used in an imaging device capable of acquiring multiple images by continuous shooting, comprising: an acquisition step of acquiring information regarding a selection of a mode for automatically determining whether or not to use a function for generating one image by combining the plurality of images; a control step of controlling the image magnification; A control method, wherein the control step controls the image magnification in a manner that differs depending on whether the mode is selected or not. (Configuration 12) A program that causes a computer to execute the control method described in Method 1.

[0036] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0037] 10c acquisition part 10d Image magnification control unit (control unit)

Claims

1. An imaging device capable of capturing multiple images by continuous shooting, an acquisition unit that acquires information regarding a selection of a mode that automatically switches between use and non-use of a function for generating one image by combining the plurality of images; a control unit that controls the image magnification; The image capturing apparatus is characterized in that the control unit controls the image magnification in a different manner depending on whether the mode is selected or not.

2. 2. The imaging device according to claim 1, wherein the function is a function of generating the image with reduced camera shake by synthesizing the plurality of images while aligning them.

3. 3. The imaging apparatus according to claim 1, wherein the control unit controls the image magnification to be constant when the mode is selected.

4. 3. The imaging device according to claim 1, wherein the control unit controls the image magnification when the mode is selected so that the image magnification is the same as the image magnification when the function is used.

5. The imaging device according to claim 1 or 2, wherein the control unit controls the image magnification to be constant when the mode is selected and continuous shooting is performed in which shooting instructions are given continuously.

6. In the mode, it is determined whether to use the function based on a relationship between a first photographing condition among the photographing conditions and a threshold value; 3. The imaging device according to claim 1, wherein the control unit does not change the image magnification when the mode is selected and the first photographing condition is the threshold value.

7. 3. The imaging device according to claim 1, wherein the control unit does not change the image magnification when the mode is selected and continuous shooting is performed in which shooting instructions are continuously given while the amount of movement of the imaging device per unit time is greater than a predetermined amount.

8. 3. The imaging device according to claim 1, wherein when the mode is selected and continuous shooting is performed in which shooting instructions are given continuously, the function cannot be switched between being used and not being used in the mode.

9. Further comprising a display unit, The imaging device according to claim 1 or 2, characterized in that, when the mode is selected, the control unit causes the display unit to display, in live view, an image corresponding to the image magnification when the function is used.

10. Further comprising a display unit, The imaging device described in claim 1 or 2, characterized in that when the mode is selected, the control unit causes the display unit to display a live view of an image corresponding to the image magnification when the function is not used, and superimposes an indicator corresponding to the image magnification when the function is used on the image.

11. Further comprising a display unit, The imaging device described in claim 1 or 2, characterized in that when the mode is selected, the control unit causes the display unit to display a live view of an image corresponding to the image magnification when the function is not used, and differentiates the display format between an area of ​​the image corresponding to the image magnification when the function is used and other areas.

12. A control method used in an imaging device capable of acquiring multiple images by continuous shooting, comprising: an acquisition step of acquiring information regarding a selection of a mode for automatically determining whether or not to use a function for generating one image by combining the plurality of images; a control step of controlling the image magnification; A control method, wherein the control step controls the image magnification in a manner that differs depending on whether the mode is selected or not.

13. A program causing a computer to execute the control method according to claim 12.

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