JP2020102795A - Imaging apparatus - Google Patents

Abstract

To provide an imaging apparatus capable of superimposing a subject at a predetermined distance interval in a photographing method that superimposes a movement of the subject, even if a moving speed of the subject is not constant.SOLUTION: The imaging apparatus includes: an imaging element; image generating means for generating an image from a signal acquired by the imaging element; image processing means for generating a multiple photographing image synthesized into one image from a plurality of continuously photographed images; means for calculating a movement amount of a moving body; and a control unit for controlling a photographing timing so that a subject has a predetermined distance interval based on the movement amount calculated by the means. The photographed images are synthesized according to an instruction of the control unit.SELECTED DRAWING: Figure 1

Description

The present invention relates to an image pickup apparatus such as a digital camera and a control method thereof, and more particularly to an image pickup apparatus capable of multiple exposure shooting and a control method thereof.

As a photographing method and function of a camera, multiple exposure photographing is known in which a plurality of images are superposed and combined into one image. Further, as a shooting method using the multiple-exposure shooting, there is a shooting method in which a plurality of moving subjects are continuously shot and combined to draw a moving trajectory of the subject in one image.

In order to enhance the quality of works using this shooting method, the motion vector of the moving subject is calculated, and the number of image frames to be combined is calculated based on the magnitude of the movement of the subject to determine the moving subject. A method has been proposed in which the image is properly contained in one image (Patent Document 1). Further, a general method of this photographing method is to superimpose subjects photographed at a constant time interval in the continuous photographing mode.

JP, 2014-23067, A

However, as described above, the method using the continuous shooting mode with a constant time interval cannot draw a beautiful trajectory of the subject unless the speed of the moving subject is constant, and the quality of the work is deteriorated due to the overlapping of the subjects. It may happen. There are many subjects whose speed is not constant, such as short-distance races on land, animals such as birds, and motor sports.

A failure example will be described with reference to FIG. When an image of a subject moving at a speed change as shown in FIG. 8A is obtained by continuous shooting at fixed time intervals, an image at the subject position as shown in FIG. 8B is shot. When these are subjected to the multiple exposure composition, the quality of the work is deteriorated due to the overlapping of the subjects or the too wide interval as shown in FIG. 8C.

In the conventional technique disclosed in the above-mentioned Patent Document 1, even if the movement of the subject is reduced to one, the overlapping of the subjects cannot be eliminated, so that the deterioration of the quality of the work due to the speed change of the subjects cannot be avoided. ..

Therefore, it is an object of the present invention to provide an imaging device capable of superimposing a subject at a predetermined distance interval even when the moving speed of the subject is not constant in a photographing method for superimposing the movement of the subject. is there.

In order to achieve the above object, the imaging device according to the present invention is
An image sensor, an image generation unit that generates an image from a signal acquired by the image sensor, an image processing unit that generates a multiple shot image that is a composite of a plurality of continuously shot images into one image, and a motion amount of a moving body. Comprising a means for calculating and a control unit for controlling the photographing timing so that the subject is at a predetermined distance interval by the amount of movement calculated by the means, and combining the images photographed according to the instructions of the control unit. Is characterized by.

According to the present invention, it is possible to provide an imaging device that can superimpose a subject at a predetermined distance interval even in a case where the moving speed of the subject is not constant in a photographing method for superimposing the motion of the subject.

3 is a flowchart showing a processing operation of the digital camera according to the first embodiment of the present invention. It is an external view of the digital camera which concerns on the Example of this invention. It is a block diagram which shows the structure of the digital camera which concerns on the Example of this invention. FIG. 6 is an explanatory diagram of a multiple exposure control method executed by the digital camera according to the first embodiment of the present invention. 7 is a flowchart showing a processing operation of the digital camera according to the second embodiment of the present invention. It is explanatory drawing of the multiple exposure control method performed with the digital camera which concerns on Example 2 of this invention. 9 is a flowchart showing a processing operation of the digital camera according to the third embodiment of the present invention. It is explanatory drawing regarding the subject with respect to a prior art.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

2A and 2B are external views of a digital camera as an example of the image pickup apparatus of the present invention. 2A is a front perspective view of the digital camera 100, and FIG. 2B is a rear perspective view of the digital camera 100.

In FIG. 2, a display unit 28 is a display unit provided on the rear surface of the camera for displaying images and various kinds of information. The outside viewfinder display unit 43 is a display unit provided on the upper surface of the camera and displays various setting values of the camera such as the shutter speed and the aperture. The shutter button 61 is an operation unit for issuing a shooting instruction. The mode changeover switch 60 is an operation unit for changing over various modes. The terminal cover 40 is a cover that protects a connector (not shown) such as a connection cable for connecting the digital camera 100 with a connection cable with an external device.

The main electronic dial 71 is a rotary operation member included in the operation unit 70, and by turning the main electronic dial 71, setting values such as shutter speed and aperture can be changed. The power switch 72 is an operation member that switches ON/OFF of the power of the digital camera 100. The sub electronic dial 73 is a rotary operation member included in the operation unit 70, and can move a selection frame and move an image. The cross key 74 is a cross key (four-way key) included in the operation unit 70 and capable of pressing the upper, lower, left, and right portions respectively. An operation can be performed according to the pressed portion of the cross key 74.

The SET button 75 is a push button included in the operation unit 70, and is mainly used for determining a selection item. The LV button 76 is included in the operation unit 70 and is a button for switching live view (hereinafter, LV) ON and OFF in the menu button. In the moving image shooting mode, it is used for instructing start and stop of moving image shooting (recording). The enlargement button 77 is included in the operation unit 70, and is an operation button for turning the enlargement mode ON and OFF and changing the enlargement ratio during the enlargement mode in the live view display in the shooting mode. In the reproduction mode, it enlarges the reproduced image and functions as an enlargement button for increasing the enlargement ratio.

The reduction button 78 is a button included in the operation unit 70 for reducing the enlargement ratio of the enlarged reproduced image and reducing the displayed image. The play button 79 is included in the operation unit 70 and is an operation button for switching between a shooting mode and a play mode. By pressing the play button 79 in the shooting mode, the mode is switched to the play mode, and the latest image among the images recorded on the recording medium 200 can be displayed on the display unit 28.

The quick return mirror 12 is instructed by the system controller 50 and is moved up and down by an actuator (not shown). The communication terminal 10 is a communication terminal for the digital camera 100 to communicate with the lens side (detachable). The eyepiece finder 16 is a looking-in type finder for observing the focusing screen 13 to confirm the focus and composition of the optical image of the subject obtained through the lens unit 150. The lid 202 is a lid for the slot in which the recording medium 200 is stored. The grip portion 90 is a holding portion having a shape that a user can easily hold with the right hand when holding the digital camera 100.

FIG. 3 is a block diagram showing a configuration example of the digital camera 100 according to the present embodiment. In FIG. 3, a lens unit 150 is a lens unit that mounts a replaceable photographing lens.

The lens 103 is usually composed of a plurality of lenses, but here, for simplicity, only one lens is shown. The communication terminal 6 is a communication terminal for the lens unit 150 to communicate with the digital camera 100 side, and the communication terminal 10 is a communication terminal for the digital camera 100 to communicate with the lens unit 150 side. The lens unit 150 communicates with the system control unit 50 via the communication terminals 6 and 10, the internal lens system control circuit 4 controls the aperture 1 via the aperture drive circuit 2, and the AF drive circuit 3. Then, the focus is adjusted by displacing the position of the lens 103.

The AE sensor 17 measures the brightness of the subject through the lens unit 150. Further, the AE sensor performs face detection, human body detection, and image acquisition for tracking, and the system control unit 50 performs face detection/human body detection/tracking calculation processing.

The focus detection unit 11 outputs the defocus amount information to the system control unit 50. The system control unit 50 controls the lens unit 150 based on it to perform the phase difference AF.

The quick return mirror 12 (hereinafter, mirror 12) is instructed by the system control unit 50 at the time of exposure, live view shooting, and moving image shooting, and is moved up and down by an actuator (not shown). The mirror 12 is a mirror for switching the light flux incident from the lens 103 between the finder 16 side and the imaging unit 22 side.

The mirror 12 is normally arranged so as to reflect the light flux toward the finder 16, but when the shooting is performed or the live view display is performed, the mirror 12 is upwardly directed so as to guide the light flux toward the imaging unit 22. Evacuate from the bounced light flux (mirror up). Further, the mirror 12 is a half mirror so that the central portion thereof can transmit a part of light, and transmits a part of the light flux so as to enter the focus detection unit 11 for performing focus detection.

By observing the focusing screen 13 through the pentaprism 14 and the finder 16, the user can confirm the focus and composition of the optical image of the subject obtained through the lens unit 150.

The shutter 101 is a focal plane shutter that can freely control the exposure time of the imaging unit 22 under the control of the system control unit 50.

The image pickup unit 22 is an image pickup device including a CCD, a CMOS device, or the like that converts an optical image into an electric signal. The A/D converter 23 converts an analog signal into a digital signal. The A/D converter 23 is used to convert an analog signal output from the imaging unit 22 into a digital signal.

The image processing unit 24 performs resizing processing such as predetermined pixel interpolation and reduction, and color conversion processing on the data from the A/D converter 23 or the data from the memory control unit 15. Further, the image processing unit 24 performs predetermined arithmetic processing using the captured image data, and the system control unit 50 performs exposure control and distance measurement control based on the obtained arithmetic result. As a result, TTL (through-the-lens) AF (auto focus) processing, AE (auto exposure) processing, and EF (flash pre-emission) processing are performed.

The output data from the A/D converter 23 is directly written to the memory 32 via the image processing unit 24 and the memory control unit 15, or via the memory control unit 15.

The memory 32 stores image data obtained by the image pickup unit 22 and converted into digital data by the A/D converter 23, and image data to be displayed on the display unit 28. The memory 32 has a storage capacity sufficient to store a predetermined number of still images, a moving image and a sound for a predetermined time. The memory 32 also serves as a memory (video memory) for displaying an image.

The D/A converter 19 converts the image display data stored in the memory 32 into an analog signal and supplies the analog signal to the display unit 28. In this way, the image data for display written in the memory 32 is displayed on the display unit 28 via the D/A converter 19.

The display unit 28 performs display according to the analog signal from the D/A converter 19 on a display device such as an LCD. A digital signal once A/D converted by the A/D converter 23 and stored in the memory 32 is converted into an analog signal in the D/A converter 19, and sequentially transferred to the display unit 28 for display, thereby displaying a through image ( Live view display) can be performed.

The in-viewfinder liquid crystal display section 41 displays a frame (AF frame) indicating the focus detection point currently being auto-focused, an icon indicating the setting state of the camera, etc., via the in-finder display section drive circuit 42. To be done.

Various set values of the camera such as a shutter speed and an aperture are displayed on the outside-finder liquid crystal display section 43 via the outside-finder display section drive circuit 44.

The non-volatile memory 56 is an electrically erasable/recordable memory, and for example, an EEPROM or the like is used. The non-volatile memory 56 stores constants for operating the system control unit 50, programs, and the like. Here, the program is a program for executing various flowcharts described later in this embodiment.

The system control unit 50 controls the entire digital camera 100. By executing the program recorded in the above-mentioned nonvolatile memory 56, each processing of this embodiment described later is realized. Reference numeral 52 denotes a system memory, which uses a RAM. In the system memory 52, constants and variables for the operation of the system control unit 50, programs read from the non-volatile memory 56, and the like are expanded. The system control unit also controls the display by controlling the memory 32, the D/A converter 19, the display unit 28, and the like.

The system timer 53 is a timekeeping unit that measures the time used for various controls and the time of a built-in clock. The mode changeover switch 60, the first shutter switch 62, the second shutter switch 64, and the operation section 70 are operation means for inputting various operation instructions to the system control section 50. The mode switch 60 switches the operation mode of the system control unit 50 to one of a still image recording mode, a moving image shooting mode, a reproduction mode, and the like.

The modes included in the still image recording mode include an auto shooting mode, an auto scene determination mode, a manual mode, an aperture priority mode (Av mode), and a shutter speed priority mode (Tv mode). Further, there are various scene modes which are shooting settings for each shooting scene, a program AE mode, a custom mode, and the like.

The mode changeover switch 60 can directly switch to one of these modes included in the menu button. Alternatively, the mode changeover switch 60 may be used to temporarily switch to the menu button and then to be switched to one of these modes included in the menu button by using another operation member. Similarly, the moving image shooting mode may include a plurality of modes.

The first shutter switch 62 is turned on during operation of the shutter button 61 provided on the digital camera 100 by so-called half-pressing (shooting preparation instruction) to generate the first shutter switch signal SW1. The first shutter switch signal SW1 starts operations such as AF (auto focus) processing, AE (automatic exposure) processing, AWB (auto white balance) processing, and EF (flash pre-flash) processing.

The second shutter switch 64 is turned on when the operation of the shutter button 61 is completed, that is, when the shutter button 61 is fully pressed (shooting instruction), and the second shutter switch signal SW2 is generated. By the second shutter switch signal SW2, the system control unit 50 starts a series of shooting processing operations from signal reading from the image pickup unit 22 to writing image data in the recording medium 200.

Each operation member of the operation unit 70 is appropriately assigned a function for each scene by selecting and operating various function icons displayed on the display unit 28, and acts as various function buttons. The function buttons include, for example, an end button, a return button, an image advance button, a jump button, a narrow-down button, an attribute change button and the like. For example, when the menu button is pressed, various settable menu screens are displayed on the display unit 28. The user can intuitively perform various settings by using the menu screen displayed on the display unit 28, and the up, down, left, and right four-way buttons and the SET button.

The operation unit 70 is various operation members as an input unit that receives an operation from the user. The operation unit 70 includes at least the following operation units. A shutter button 61, a main electronic dial 71, a power switch 72, a sub electronic dial 73, a cross key 74, a SET button 75, an LV button 76, an enlarge button 77, a reduce button 78, and a play button 79.

The power supply control unit 80 includes a battery detection circuit, a DC-DC converter, a switch circuit that switches blocks to be energized, and the like, and detects whether or not the battery is mounted, the type of the battery, and the remaining battery level. Further, the power supply control unit 80 controls the DC-DC converter based on the detection result and the instruction of the system control unit 50, and supplies a necessary voltage to each unit including the recording medium 200 for a necessary period.

The power supply unit 30 includes a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, a NiMH battery, a Li battery, an AC adapter, or the like. The recording medium I/F 18 is an interface with the recording medium 200 such as a memory card or a hard disk. The recording medium 200 is a recording medium such as a memory card for recording captured images, and is composed of a semiconductor memory, a magnetic disk, or the like.

The communication unit 54 is connected by a wireless or wired cable and transmits/receives a video signal and an audio signal.

The attitude detection unit 55 detects the attitude of the digital camera 100 with respect to the direction of gravity. Based on the posture detected by the posture detection unit 55, it is determined whether the image photographed by the image pickup unit 22 is an image photographed with the digital camera 100 held horizontally or vertically. It can be determined.

<Example 1>
Hereinafter, a method for controlling a digital camera according to an exemplary embodiment of the present invention will be described with reference to FIGS. 1 and 4. In this embodiment, a procedure relating to control of a shooting method for drawing a trajectory of a subject when shooting is performed by a digital camera having a multiple exposure shooting function will be described.

FIG. 1 is a flowchart of multiple exposure control of a digital camera. Each process in this flowchart is realized by the system control unit 50 expanding a program stored in the non-volatile memory 56 into the system memory 52 and executing the program. The control of this flowchart is based on the premise that the user activates the digital camera 100, completes the camera settings such as shutter speed and aperture, and shoots a composite image that draws the trajectory of a moving subject using multiple exposure shooting. There is.

In S101, it is determined whether or not the user has pressed the first shutter switch 62 (hereinafter, SW1). If SW1 is pressed, the process proceeds to S102, and if SW1 is not pressed, S101 is repeated.

In S102, an auto focus process (hereinafter, AF process) and an automatic exposure control process (hereinafter, AE process) are performed. In the AF process, the focus detection unit 11 acquires the defocus amount information, and the system control unit 50 controls the lens unit 150 based on the defocus amount information to perform the phase difference AF. In the AE process, the AE sensor 17 measures the brightness of the subject that has passed through the lens unit 150, and the system control unit 50 performs the exposure calculation process based on it.

In S103, the main subject is discriminated. Examples of the main subject discrimination include discrimination based on a distance measuring point selected by the user and discrimination based on a face detection/human body detection result using the AE sensor 17. Simultaneously with the main subject discrimination, the coordinate position (x(n), y(n)) of the subject is calculated. In the case of the main subject determination based on the focus detection point, the focus detection point position is the coordinate position of the subject, and in the case of the main subject determination based on the face detection/human body detection result, the center coordinate of the face/human body detection is (x (N), y(n)). n is a number assigned to the images taken for multiple exposure, and is assigned in order from n=1. Therefore, (x(1), y(1)) is initially obtained.

In S104, it is determined whether or not the user has pressed the second shutter switch 64 (hereinafter, SW2). If SW2 is pressed, it is considered that the user has given a shooting instruction, and the process proceeds to S105. If SW2 is not pressed, the process returns to S101.

In S105, a captured image is acquired in response to a shooting instruction. The system control unit 50 executes a series of shooting processing operations from reading a signal from the imaging unit 22 to writing image data in the recording medium 200. However, if the user has set not to save captured images other than the combined image as the setting of the multiple exposure function, the image data writing to the recording medium 200 is not performed.

In S106, it is determined whether or not the user keeps pressing the SW2. If SW2 is held, the process proceeds to S107. If SW2 is not held and is off, the process proceeds to S110, and end processing such as image composition and storage is performed. The termination process after S110 will be described later.

In S107, the AE/AF processing and the tracking processing of the subject determined to be the main subject in S103 are performed. The main subject is the subject for which the user wants to overlap the loci. As the tracking processing method, tracking by face detection/human body detection, color tracking, or the like is used. Simultaneously with the tracking processing, the coordinate position (xt(t), yt(t)) of the subject is calculated. Let t be time.

In S108, the motion amount of the subject is calculated. Motion detection is performed using the coordinate position calculated in S107. Using the position (xt(t), yt(t)) of the main subject at each time and the position (x(n), y(n)) of the main subject of the image captured in S105, the following formula (1) is used. The amount of movement Lt of the subject is calculated.

Further, the movement amount of the subject may be compared with the movement amount in the x direction and the movement amount in the y direction, and the movement amount considering only the larger one may be set as the movement amount of the subject. The calculation method in that case is the following mathematical formulas (2) and (3).

When (xt(t)-x(n))≧(yt(t)-y(n)),

When (xt(t)-x(n))<(yt(t)-y(n)),

For example, FIG. 4B shows the position of a subject moving at a speed as shown in FIG. As an example, the main subject position for calculating the image acquisition timing of the third image is shown by (xt(t), yt(t)) in FIG. At this time, the amount of movement of the main subject is calculated using (xt(t), yt(t)) and (x(2), y(2)).

In S109, it is determined whether or not the next shooting timing is optimal, depending on whether or not the motion amount Lt calculated in S108 is equal to or greater than a predetermined threshold value Lth. Here, Lth is an interval between subjects when the user shoots a work in which the trajectory of the subject is drawn by multiple exposure shooting. Lth may have a predetermined value as a digital camera, or may be a value that can be set by the user. In addition, Lth may be changed by detecting the state of the subject.

For example, when drawing the trajectory of a dancer or a gymnast, the subjects may overlap even at equal intervals depending on the posture such as spreading hands. In that case, Lth may be variable, and the interval may be changed according to the posture so as not to overlap.

If Lt calculated in S108 is smaller than Lth, the main subject has not moved within a predetermined interval, so the next image acquisition is not performed and the process returns to S106 to perform SW2 holding determination, tracking processing, and subject movement amount calculation. Do it again. If Lt calculated in S108 is greater than or equal to Lth, the main subject is moving at a predetermined interval, so the process returns to S105 and the next image is acquired.

Here, it is assumed that the digital camera is ready to capture the next image before the subject moves Lth. After the image is acquired, while SW2 is held, the processes of S105 to S109 are repeated, and the images used for multiple exposure are continuously photographed so that the distance intervals of the subjects are equal. When SW2 is turned off, the image acquisition is stopped and the process proceeds to S110.

In S110, image synthesis of the acquired images is performed. Compositing is performed using all images captured while executing S101 to S109. At this time, as a synthesizing method, image synthesizing is performed according to the multiple exposure mode set by the user, such as addition, averaging, comparison (bright), comparison (dark). If the control is performed according to the flow described above, it is possible to photograph a work that has been subjected to multiple exposure at equal distance intervals, as shown in FIG. 4C, even for a subject that moves at a non-constant speed.

Finally, in S111, the composite image acquired in S110 is written and saved in the recording medium 200.

As described above, according to the present embodiment, when the user wants to shoot a work in which the trajectory of a moving subject is drawn using multiple exposure shooting, even if the moving speed of the subject is not constant, the object to be drawn as the trajectory is The distance interval can be made constant and the quality of the work can be improved.

<Example 2>
Hereinafter, a method for controlling a digital camera according to an exemplary embodiment of the present invention will be described with reference to FIGS.

FIG. 5 is a flowchart of multiple exposure control of the digital camera 100.

The control method from S501 to S509 is the same as S101 to S109 of the first embodiment. In S510, it is determined whether or not the shooting preparation is completed at the timing when it is determined in S509 that the moving distance of the subject has exceeded the threshold value Lth. For example, although it is desired to perform shooting at the timing when it is determined that the moving distance of the subject has exceeded the threshold value Lth, shooting may not be possible at that timing due to the frame speed specifications of continuous shooting.

This will be described with reference to FIG. When the subject is moving with a speed change as shown in FIG. 6A, the fifth frame of the captured image shown by e in FIG. 6B can be captured even with the frame speed specification of the digital camera. It is conceivable that the sixth and subsequent captured images indicated by ‘may not be in time due to the frame speed specifications. In such a case, in order to shoot at a timing that is an integral multiple of Lth, the process shifts to S512 and waits until a shooting ready state is reached. If shooting is possible, the process proceeds to S513. On the other hand, if the shooting can be performed at the timing when it is determined that the moving distance of the subject exceeds the threshold value Lth, the process proceeds to S511.

In S511, it is determined whether or not the moving distance Lt of the subject is close to Lth. Here, p is a value that defines the determination width for determining that Lt is close to Lth. The smaller p is, the more equal the distance distance between the subjects is. When the moving distance Lt of the subject is close to Lth, the process proceeds to S505 to acquire an image, and when the moving distance Lt of the subject is not close to Lth, the process proceeds to S513 to detect the shooting timing.

In S513, it is determined whether or not the user keeps pressing the SW2. If SW2 is held, the process proceeds to S514. If SW2 is not held and is off, the process advances to step S519 to perform end processing such as image composition and storage. The ending process after S519 will be described later.

In S514, the inter-frame adjustment flag is turned on. This flag is used to determine whether or not it is necessary to select an image for performing a combining process when performing image combination.

In S515, the AE/AF process, the tracking process of the main subject, and the calculation of the subject position are performed as in S507.

In S516, the motion amount Lt of the subject is calculated as in S508.

In S517, it is determined whether or not it is optimal as the next shooting timing depending on whether or not the motion amount Lt of the subject calculated in S516 is close to an integral multiple of the predetermined threshold value Lth. As an example, the following formula (4) is used for the determination.

Here, k is an integer, and p is a value defining a determination width for determining that Lt is close to an integral multiple of Lth. If the motion amount Lt of the subject calculated in S516 is not close to an integral multiple of the predetermined threshold value Lth, the process returns to S515, and the tracking process and the motion amount calculation of the subject are performed again. When the motion amount Lt of the subject calculated in S516 is close to an integral multiple of the predetermined threshold value Lth, the process proceeds to S518, and the value of k is recorded.

After that, the process proceeds to S505, and an image is acquired. After the image is acquired, the processes of S505 to S518 are repeated while SW2 is held, and the images used in the multiple exposure are continuously photographed so that the distance intervals of the subjects are equal. When SW2 is turned off, image acquisition is stopped and the process proceeds to S519.

In S519, it is determined whether the inter-frame adjustment flag is turned on. If it is on, the process proceeds to S520, and if it is off, the process proceeds to S521.

In S520, a photographed image to be subjected to multiple exposure is selected depending on how many times the distance is longer than a predetermined threshold value Lth when the frame-to-frame adjustment is performed. The value of the integer k recorded in S518 is used for image selection. As an example, the process when k=2 will be described with reference to FIG. When the loci of the subject moving at the speed and position shown in FIGS. 6A and 6B are overlapped, the distance between the subjects is Lth until the fifth captured image as shown in FIGS. 6B and 6C. You can shoot with. However, after the sixth image in which the moving speed of the subject becomes faster, the frame speed cannot catch up at fth, g′, and h′ of the Lth distance interval, and shooting is impossible.

In such a case, the shooting timing is controlled so that the distance interval is twice the Lth as indicated by f, g, and h shown in FIGS. Then, when the shooting is completed up to the eighth sheet and the SW2 is turned off, the images a, c, e, f, g, and h are set so that the distance intervals of the subjects become equal as shown in FIG. 6D. Select and combine images. As described above, in S520, images to be combined are selected from the captured images so that the distance intervals between the subjects are equal.

In step S521, the selected image or all the images are combined. Finally, in S522, the composite image acquired in S521 is written and stored in the recording medium 200.

As described above, according to the present embodiment, even when it is impossible to shoot at the distance interval set by the rate-controlling of the specification such as the frame speed, the distance interval of the object drawn as the trajectory can be made constant, and the quality of the work can be improved. Can be increased.

<Example 3>
Hereinafter, a method for controlling a digital camera according to an exemplary embodiment of the present invention will be described with reference to FIG. In this embodiment, a procedure relating to control of a shooting method for drawing a trajectory of a subject when shooting is performed by a digital camera having a multiple exposure shooting function will be described.

FIG. 7 is a flowchart of multiple exposure control of the digital camera. Each process in this flowchart is realized by the system control unit 50 expanding a program stored in the non-volatile memory 56 into the system memory 52 and executing the program. The control of this flowchart is based on the premise that the user activates the digital camera 100, completes the camera settings such as shutter speed and aperture, and shoots a composite image that draws the trajectory of a moving subject using multiple exposure shooting. There is.

In S701, it is determined whether SW1 is pressed by the user. If SW1 is pressed, the process proceeds to S702, and if SW1 is not pressed, S701 is repeated.
In S702, AF processing and AE processing are performed.

In S703, it is determined whether SW2 is pressed by the user. If SW2 is pressed, it is considered that the user has given a shooting instruction, and the process proceeds to S704. If SW2 is not pressed, the process returns to S701.

In step S704, the AF process and the AE process are performed just before the image acquisition as in step S702.

In step S705, a captured image is acquired according to the shooting instruction. The system control unit 50 executes a series of shooting processing operations from reading a signal from the imaging unit 22 to writing image data in the recording medium 200. However, if the user has set not to save captured images other than the combined image as the setting of the multiple exposure function, the image data writing to the recording medium 200 is not performed.

In S706, the main subject is discriminated from the image acquired in S705. Examples of the main subject discrimination include discrimination based on a distance measuring point selected by the user and discrimination based on a face detection/human body detection result using the AE sensor 17. At the same time when the main subject is determined, the coordinate position (x(n), y(n)) of the subject is calculated. n is a number assigned to the images taken for multiple exposure, and is assigned in order from n=1. Therefore, (x(1), y(1)) is initially obtained.

In S707, the subject position calculated in S706 is added to each image. This subject position information is used when combining images.

In S708, it is determined whether or not the user keeps pressing the SW2. While SW2 is held, S704 to S707 are repeatedly performed, and continuous shooting is performed at the fastest frame speed possible. If SW2 is not held and turned off, the process proceeds to S709.

In step S709, the user sets the distance interval of the subject to be superimposed as a trajectory by using the multiple-exposure shooting. However, the initial set value may be held as a digital camera. Further, it may be a UI that can be set intuitively by using an operation member such as a slider.
In S710, the picked-up images are selected so that the subject distance interval set in S709 is obtained. At this time, image selection is performed using the subject position given to each image at the time of shooting.

In S711, image composition of the image selected in S711 is performed. As a synthesizing method, image synthesizing is performed according to the multiple exposure mode set by the user, such as addition, averaging, comparison (bright), comparison (dark).

In S712, the image composition result is displayed, and the user determines the composition result. In the case of NG, the process returns to S709. The distance interval preferred by the user is reset, and steps S710 and S711 are executed. If it is determined that the combined result is OK, the process proceeds to S713.

Finally, in S713, the composite image acquired in S711 and determined by the user to be OK in S712 is written and saved in the recording medium 200.

As described above, according to the present embodiment, the user sets the subject distance interval for the photographed image photographed at the maximum frame speed specification, thereby confirming the image of the work drawn as the trajectory and performing the image combination. It is possible to obtain works that the user likes.

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 can be made within the scope of the gist thereof.

100 image pickup device, 22 image pickup device, 50 image generation means (calculation means, control unit),
23, 24, 50 image processing means

Claims (6)

An image sensor (22),
An image generating means (50) for generating an image from the signal acquired by the image sensor,
Image processing means (23, 24, 50) for generating a multiple shot image that is combined into one image from a plurality of continuously shot images,
Means (50) for calculating the amount of movement of the moving body,
A control unit (50) for controlling the photographing timing so that the subject has a predetermined distance interval based on the amount of movement calculated by the means;
An image pickup apparatus (100) characterized by synthesizing images taken by an instruction of the control unit. The image pickup apparatus (100) according to claim 1, wherein the predetermined distance interval is determined by user setting. The imaging device (100) according to claim 1,
The image pickup apparatus (100) according to claim 1, wherein the predetermined distance interval is variable and is determined according to a state of a subject. When it is not possible to satisfy the predetermined predetermined distance interval at the continuous shooting frame speed, a control unit (50) is provided for controlling the shooting timing so that the distance interval is a constant multiple of the predetermined distance interval. The imaging device (100) according to claim 1. An image sensor (22),
An image generating means (50) for generating an image from the signal acquired by the image sensor,
Image processing means (23, 24, 50) for generating a multiple shot image that is combined into one image from a plurality of continuously shot images,
Having an image analysis means (50),
An image pickup apparatus (100), characterized in that a main subject and its position are calculated from a photographed image by the image analysis means, and images are selected such that the distance between the subjects becomes a predetermined distance and the images are combined. The image pickup apparatus (100) according to claim 5, wherein the user can select the predetermined distance from a combination result.