Image capturing device, control method of image capturing device, and program

Abstract

To provide a technique for suppressing unnecessary switching of a main portion in a captured image.SOLUTION: An image capturing device includes acquisition means for acquiring an image of a subject, detection means for detecting a first portion and a second portion of the subject from the image, search area setting means for setting an arbitrary area within the image as a search area, and processing target setting means for setting an area indicating the first portion detected by the detection means and an area indicating the second portion, and either the first portion or the second portion as a processing target for the image, according to the overlap with the search area. When the first portion is not set as the target, the processing target setting means sets the first portion as the target when a reduced area obtained by reducing the area indicating the first portion is overlapped with the search area.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] In recent years, digital cameras have generally been equipped with the function of detecting a subject from image signals continuously output from an image sensor, and then photographing the subject by adjusting the focus, brightness, and color to optimal conditions.

[0003] It has also become common to detect multiple parts of a single subject, and for example, technology is being used to detect the pupils, face, head, torso, etc. of a person as a subject and use them in photography. In Patent Document 1, in an imaging device that detects multiple parts of a subject, a first part and a second part are linked, and when, for example, a search area corresponding to an AF (autofocus) area comes into contact with the area of ​​one part, the second part becomes the target of processing such as focusing.

[0004] In the technology of Patent Document 1, even if the second part is not within the AF area, the second part is the target of processing such as focusing. However, if the user expects processing such as focusing to be performed on a part within the AF area, it is undesirable to perform processing such as focusing on a part outside the AF area. Therefore, for example, a method can be considered in which the detected part outside the AF area is not the target of processing such as focusing, and the target of processing such as focusing is determined from the detected part that overlaps with the AF area. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2023-128820 Summary of the Invention [Problem to be solved by the invention]

[0006] When the above method is used to determine the processing target, such as focus, from the detection area that overlaps with the AF area, if the AF area and the detection area are in contact with each other, there is a possibility that the AF area and the detection area will repeatedly be in contact with each other and then separated from each other due to fluctuations in the position of the detection area. As a result, the processing target, such as focus, may be frequently switched in the imaging device, which may cause flickering on the display screen.

[0007] The present invention has been made in view of the above, and has an object to provide a technique for suppressing unnecessary switching of the main part in a captured image. [Means for solving the problem]

[0008] The imaging device of the present invention comprises an acquisition means for acquiring an image of a subject, a detection means for detecting a first part and a second part of the subject from the image, an area setting means for setting any area within the image as a search area, and a target setting means for setting either the first part or the second part as a target for image processing depending on whether the area indicating the first part and the area indicating the second part detected by the detection means overlaps with the search area, wherein the target setting means does not set the first part as the target when the area indicating the first part, excluding a reduced area obtained by reducing the area, overlaps with the search area when the first part is not set as the target, and sets the first part as the target when the reduced area overlaps with the search area.

[0009] Furthermore, an imaging device according to the present invention comprises an acquisition means for acquiring an image of a subject, a detection means for detecting two or more parts of the subject from the image, an area setting means for setting any area within the image as a search area, a target setting means for setting one of the two or more parts as a target for image processing depending on whether the area indicating each of the two or more parts detected by the detection means overlaps with the search area, and a priority setting means for setting a priority for the setting of the target for the two or more parts detected by the detection means, wherein when two or more of a plurality of areas indicating a plurality of parts respectively overlap with the search area, the target setting means sets the part with the highest priority among the two or more parts corresponding to each of the two or more areas as the target, and when another part with a higher priority than the part set as the target has not been set as the target, even if the area obtained by excluding a reduced area obtained by reducing the area indicating the other part overlaps with the search area, the target setting means does not set the other part as the target, and when the reduced area overlaps with the search area, the imaging device is characterized in that

[0010] In addition, a control method for an imaging device according to the present invention includes an acquisition step for acquiring an image of a subject, a detection step for detecting a first part and a second part of the subject from the image, a region setting step for setting any region within the image as a search region, and a target setting step for setting either the first part or the second part as a target for image processing depending on whether the region indicating the first part and the region indicating the second part detected by the detection step overlap with the search region, wherein the target setting step does not set the first part as the target even if the region obtained by excluding a reduced region obtained by reducing the region indicating the first part overlaps with the search region when the first part is not set as the target, and when the reduced region overlaps with the search region, the control method for an imaging device is characterized in that

[0011] Furthermore, a control method for an imaging device according to the present invention includes an acquisition step of acquiring an image of a subject, a detection step of detecting two or more parts of the subject from the image, an area setting step of setting an arbitrary area within the image as a search area, an object setting step of setting one of the two or more parts as an object of image processing in accordance with an overlap between an area indicating each of the two or more parts detected by the detection step and the search area, and a priority setting step of setting a priority for setting the object for the two or more parts detected by the detection step, and when two or more of a plurality of regions respectively indicating positions overlap with the search region, the region with the highest priority among two or more regions corresponding to the two or more regions is set as the target, and the target setting step does not set the other region as the target even if an area obtained by excluding a reduced region obtained by reducing the region indicating the other region overlaps with the search region when another region having a higher priority than the region set as the target is not set as the target, and when the reduced region overlaps with the search region, the other region is set as the target. [Effects of the Invention]

[0012] According to the present invention, by reducing the detection area of ​​the part that is preferentially set as the main part and determining the main part, it is possible to reduce the frequency of switching of the main part due to changes in the search area and the detection area of ​​the part. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of an imaging device according to a first embodiment; [Figure 2] 1 is a flowchart illustrating an example of processing executed by the imaging device according to the first embodiment. [Figure 3] FIG. 1 is a diagram schematically illustrating processing in an imaging device according to a conventional technique. [Figure 4] FIG. 1 is a diagram schematically illustrating processing in an imaging device according to a first embodiment. [Figure 5] FIG. 10 is a diagram schematically illustrating processing in an imaging device according to a modified example. [Figure 6] A flowchart illustrating an example of processing executed by an imaging device according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the embodiments described below are examples of means for realizing the present invention, and may be modified or changed as appropriate depending on the configuration of an apparatus to which the present invention is applied and various conditions. Furthermore, it is also possible to combine the various embodiments as appropriate. Furthermore, in the description of the following embodiments, it is assumed that the imaging apparatus has a function of detecting the face and upper body of a person in an image, setting a portion that overlaps with a search area as a main portion, and performing focusing processing on the main portion.

[0015] First Embodiment 1 is a diagram showing an example of the configuration of an imaging device 1 according to a first embodiment of the present invention, and shows the configuration of a mirrorless camera (hereinafter referred to as camera) equipped with a function for taking the subject closest to the imaging device 1 as the main subject. Each of the components that make up the imaging device 1 will be described below.

[0016] The interchangeable lens 100 is one type of optical device that can be attached to the camera body 120. The interchangeable lens 100 is equipped with a photographing lens unit 101 that includes a main photographing optical system 102, an aperture 103 that adjusts the amount of light, and a focus lens group 104 that adjusts the focus.

[0017] A microcomputer 111 for controlling the lens system of the interchangeable lens 100 (hereinafter referred to as the lens control unit) includes an aperture control unit 112 that controls the operation of the aperture 103, and a focus lens control unit 113 that controls the operation (drive) of the focus lens group 104. The focus lens control unit 113 drives the focus lens group 104 in the optical axis direction of the photographing lens unit 101 based on focus lens drive information acquired from the camera body unit 120, and adjusts the focus of the camera.

[0018] The focus lens group 104 may have multiple focus lenses or may have only one focus lens. For simplicity's sake, FIG. 1 shows a fixed-focus lens as an example of an interchangeable lens, but it may also be a lens with a changeable focal length (zoom lens). If the focus lens group 104 includes a zoom lens, the focus lens control unit 113 acquires focal length information from an encoder output that detects the zoom lens position. If the focus lens group 104 includes a lens with an image stabilization function, the focus lens control unit 113 also controls a shift lens group for image stabilization.

[0019] The camera body 120 includes a shutter 121 used for exposure control, and an image sensor 122 such as a CMOS (complementary metal-oxide semiconductor) sensor. An image signal output from the image sensor 122 is processed by an analog signal processing circuit 123 and then sent to a camera signal processing circuit 124.

[0020] A camera system control microcomputer (hereinafter referred to as the camera control unit) 131 in the camera body 120 controls the entire imaging device 1. For example, the camera control unit 131 controls the driving of a shutter drive motor (not shown) to drive the shutter 121. The memory card 125 is a recording medium that records data of captured images. Information indicating the depression state of a release switch 181 operated by a user of the imaging device 1 is sent to the camera control unit 131, and an image captured in accordance with the depression state is stored in the memory card 125.

[0021] The display unit 171 includes a display device such as a liquid crystal panel (LCD) that displays an image that the user is about to capture with the camera and an image that has been captured. Panel 172 is an operation unit that allows the user to specify coordinates on display unit 171 with a finger or a touch pen, and can be configured integrally with display unit 171. For example, touch panel 172 can be configured as an in-cell type that is built into the display surface of display unit 171, with a light transmittance that does not interfere with the display on display unit 171. Input coordinates on touch panel 172 are associated with display coordinates on display unit 171. This makes it possible to configure a GUI (Graphical User Interface) that allows the user to directly operate the screen displayed on display unit 171. The operation state of touch panel 172 is managed by camera control unit 131.

[0022] The camera body 120 has a mount contact 161, which is a communication terminal for communicating with the interchangeable lens 100, on its mount surface with the interchangeable lens 100. The interchangeable lens 100 also has a mount contact 114, which is a communication terminal for communicating with the camera body 120, on its mount surface with the camera body 120.

[0023] The lens control unit 111 and the camera control unit 131 control communication so that serial communication is performed at a predetermined timing via the mount contact units 114 and 161. As a result, focus lens driving information, aperture driving information, etc. are sent from the camera control unit 131 to the lens control unit 111, and optical information such as focal length is sent from the lens control unit 111 to the camera control unit 131.

[0024] The camera signal processing circuit 124 includes a body part detection unit 141 as a block related to this embodiment. The body part detection unit 141 detects facial parts of a person as a subject from a captured image and outputs the detection information. The body part detection unit 141 also detects upper body parts of the person from the image and outputs the detection information. The detection result by the body part detection unit 141 is sent to the camera control unit 131.

[0025] Camera control unit 131 has a search area setting unit 150 that sets a search area based on the coordinates of the AF area or the like displayed on display unit 171. Camera control unit 131 also has a main part setting unit 151 that sets any part of the subject in the image as the main part of the subject to be focused on. Based on the detection result received from part detection unit 141, main part setting unit 151 sets, as an example, either the face or the upper body of the subject as the main part. Alternatively, main part setting unit 151 may not set a main part for the subject (determine no main part).

[0026] The camera control unit 131 includes a display frame setting unit 152 that displays an AF area and a subject detection frame for an image displayed on the display unit 171. The camera control unit 131 also includes an AF target setting unit 153 that notifies the focus detection unit 154 of a main area as a focus target for AF. The focus detection unit 154 performs focus detection processing within the main area based on an image signal indicating the focus target notified by the AF target setting unit 153. Here, the focus detection processing is performed using, for example, a known phase difference detection method or contrast detection method. When performing focus detection processing using phase difference detection, the focus detection unit 154 performs a process of calculating the amount of image shift by performing a correlation operation on a pair of image signals having parallax, or a process of further converting the image shift amount into a defocus amount. Furthermore, the focus detection unit 154 can convert the defocus amount into a focus lens drive amount based on, for example, the sensitivity of the interchangeable lens 100 when driving the lens.

[0027] The camera control unit 131 transmits the focus lens driving amount detected by the focus detection unit 154 to the lens control unit 111. The focus lens control unit 113 controls the driving of the focus lens based on the focus lens driving information received from the camera control unit 131. The aperture control unit 112 controls the aperture of the lens based on the aperture amount received from the camera control unit 131.

[0028] Next, a description will be given of the processing executed by the imaging device 1 in this embodiment. Fig. 2 shows a flowchart of the processing executed by the imaging device 1 in this embodiment. Fig. 2 shows an example of processing in which, after starting up the imaging device 1, the camera control unit 131 of the imaging device 1 detects the face and upper body of the subject from an acquired image, sets a main part, and executes a focusing process on the main part.

[0029] In step S201, the main part setting unit 151 sets a state in which a main part is not set in the image to be acquired (a state without a main part). The processing in step S201 is processing equivalent to initializing the main part setting before acquiring the first image after starting up the imaging device 1.

[0030] Next, in step S202, the image capturing device 1 captures an image of the subject, and the signal captured from the image sensor 122 is processed by the analog signal processing circuit 123. The signal output from the analog signal processing circuit 123 is then sent to the camera signal processing circuit 124. As a result, an image of the subject is captured by the camera signal processing circuit 124. Here, the camera signal processing circuit 124 is an acquisition means for acquiring the image of the subject. Also, in step S202, the search area setting unit 150 is an area setting means for setting any area within the acquired image as a search area. For example, the search area setting unit 150 sets the search area so that it overlaps with the AF area within the image. Also, the search area setting unit 150 changes the position of the search area in accordance with the movement of the AF area within the image.

[0031] Next, in step S203, body part detection unit 141 executes a process for detecting the face and upper body of the subject on the image acquired in step S202. The detection results of the face of the subject and the upper body of the subject by body part detection unit 141 are each sent to camera control unit 131. Here, the face of the subject is a first body part of the subject, and the upper body of the subject is a second body part of the subject. Furthermore, body part detection unit 141 is a detection means for detecting the first body part and the second body part of the subject from the image.

[0032] Next, in step S204, the camera control unit 131 determines whether or not the detection of the subject's face has been successful based on the detection result in step S203. If the camera control unit 131 determines that the subject's face has been detected in the image, that is, that the detection of the subject's face has been successful (S204: YES), the process proceeds to step S205. On the other hand, if the camera control unit 131 determines that the subject's face has not been detected in the image, that is, that the detection of the subject's face has failed (S204: NO), the process proceeds to step S206.

[0033] In step S205, the camera control unit 131 determines whether or not the detection of the upper body of the subject has been successful based on the detection result in step S203. If the camera control unit 131 determines that the upper body of the subject has been detected in the image, that is, that the detection of the upper body of the subject has been successful (S205: YES), the process proceeds to step S207. On the other hand, if the camera control unit 131 determines that the upper body of the subject has not been detected in the image, that is, that the detection of the upper body of the subject has failed (S205: NO), the process proceeds to step S212.

[0034] In step S206, similarly to step S205, the camera control unit 131 determines whether or not the detection of the upper body of the subject has been successful based on the detection result in step S203. If the camera control unit 131 determines that the detection of the upper body of the subject has been successful (S206: YES), the process proceeds to step S213. In addition, the camera control unit 131 If it is determined that detection of the upper body of the subject has failed (S206: NO), the process proceeds to step S214. Note that the process of step S205 is different in that it determines the detection result of the upper body when face detection is successful, whereas the process of step S206 is different in that it determines the detection result of the upper body when face detection is unsuccessful.

[0035] In step S207, main part setting section 151 sets an area to be used for setting the main part based on the face and upper body detected in the image acquired in step S202. In the present embodiment, as an example, main part setting section 151 sets the face detection area and upper body detection area detected by part detection section 141 in step S203 as the area to be used for setting the main part.

[0036] Next, in step S208, the camera control unit 131 determines whether the current main body part is set to the face. If the main body part is set to the face (S208: YES), the camera control unit 131 proceeds to step S210. If the main body part is not set to the face (S208: NO), the camera control unit 131 proceeds to step S209. Note that, during the first operation after startup of the imaging device 1, the main body part setting is initialized in step S201, and there is no main body part, i.e., the main body part is not set to the face. Therefore, when step S208 is executed for the first time after startup of the imaging device 1, the process proceeds from step S208 to step S209.

[0037] In step S209, the camera control unit 131 reduces the face detection area used for determining the main part. Note that the amount of reduction of the face detection area in step S209 may be constant or may be determined according to the size of the detection area or search area.

[0038] Next, in step S210, the camera control unit 131 determines whether the search area and the face detection area overlap. If the camera control unit 131 determines that the search area and the face detection area overlap (S210: YES), the process proceeds to step S212. If the camera control unit 131 determines that the search area and the face detection area do not overlap (S210: NO), the process proceeds to step S211.

[0039] In step S211, the camera control unit 131 determines whether the search area and the upper body detection area overlap. If the camera control unit 131 determines that the search area and the upper body detection area overlap (S211: YES), the process proceeds to step S213. If the camera control unit 131 determines that the search area and the face detection area do not overlap (S211: NO), the process proceeds to step S212.

[0040] In step S212, the main part setting unit 151 sets the subject's face as the main part in the captured image acquired in step S202. Furthermore, the display frame setting unit 152 displays a subject detection frame indicating the area of ​​the subject's face that has been set as the main part on the display unit 171. The display frame setting unit 152 is a display means that displays a frame corresponding to the part set as the main part. Furthermore, if the face detection area used for determining the main part is reduced in step S209, the camera control unit 131 restores the face detection area used for determining the main part to the detection area before the reduction. Therefore, in this embodiment, the reduced face detection area is used in the determination process in step S210, and after the face is set as the main part, the size of the face detection area is restored. This allows the imaging device 1 to reduce the phenomenon of frequent changes in the setting of the main part due to frequent changes in the overlap between the search area and the detection area caused by camera shake or the like when the size of the detection area is not changed. The camera control unit 131 then proceeds to step S215.

[0041] In this embodiment, in step S212, a subject detection frame is displayed on the image. The face area is determined to be the unreduced face detection area rather than the area reduced in step S209. If it is determined in step S210 that the search area and face area overlap and the process proceeds to step S212, the face is set as the main part without determining whether the search area and upper body area overlap in step S211. That is, if both the face detection area and the upper body detection area overlap with the search area, main part setting unit 151 sets the face as the main part. As a result, in imaging device 1, if the search area overlaps both the face area and the upper body area, the face is preferentially set as the main part.

[0042] Furthermore, in this embodiment, in image capture device 1, if the search area does not overlap with either the face detection area or the upper body detection area, the process proceeds in the order of step S210 (NO), step S211 (NO), and step S212. Therefore, if neither the face detection area nor the upper body detection area overlaps with the search area, main part setting section 151 sets the face as the main part. As a result, in image capture device 1, if the search area does not overlap with either the face area or the upper body area, the face is preferentially set as the main part.

[0043] In step S213, main part setting unit 151 sets the upper body of the subject as the main part in the captured image acquired in step S202. Furthermore, display frame setting unit 152 displays a subject detection frame indicating the area of ​​the subject's upper body that has become the main part on display unit 171. Furthermore, if the face detection area used for main part determination is reduced in step S209, camera control unit 131 returns the face detection area used for main part determination to the detection area before reduction. Then, camera control unit 131 proceeds to the process at step S215. In this embodiment, main part setting unit 151 is a target setting means that sets the detected part as a target for image processing in accordance with the overlap between the area indicating the part and the search area.

[0044] In step S214, the main part setting unit 151 sets no main part. As a result, no main part is set in the captured image acquired in step S202. Then, the camera control unit 131 proceeds to step S215.

[0045] In step S215, the camera control unit 131 determines whether the search area overlaps with the area of ​​the main part set in step S212 or step S213. If the camera control unit 131 determines that the search area overlaps with the area of ​​the main part set in step S212 or step S213 (S215: YES), the camera control unit 131 proceeds to step S216. If the camera control unit 131 determines that the search area does not overlap with the area of ​​the main part set in step S212 or step S213 (S25: NO), the camera control unit 131 proceeds to step S217. Note that if step S215 is executed with no main part set in step S214, the camera control unit 131 determines that the search area does not overlap with the area of ​​the main part, and proceeds to step S217. The determination process in step S215 can also be performed in accordance with the determination results in steps S204, S205, S206, S210, and S211. Therefore, the camera control unit 131 may store the determination results in steps S204, S205, S206, S210, and S211, and perform the determination process in step S215 based on the stored determination result.

[0046] Next, in step S216, the AF target setting unit 153 sets the area of ​​the main part in the captured image acquired in step S202 as the AF target and performs focusing processing. After completing the focusing processing, the camera control unit 131 returns the processing to step S202, acquires a captured image of the next frame, and repeats the above processing. Note that after completing step S216, the set main part is not reset, and the process moves to image processing of the next frame with the setting of the main part maintained.

[0047] Furthermore, in step S217, the AF target setting unit 153 sets the search area as the AF target in the captured image acquired in step S202 and performs focusing processing. Therefore, according to this embodiment, in the imaging device 1, the main part setting unit 151 sets the search area as the target area for focusing processing when neither the face nor the upper body is set as the main part. Furthermore, even when the face or the upper body is set as the main part and the detection area of ​​the face or the upper body set as the main part does not overlap with the search area, the main part setting unit 151 sets the search area as the target area for focusing processing. After completing the focusing processing, the camera control unit 131 returns the processing to step S202, acquires a captured image of the next frame, and repeats the above processing. Note that after completing step S216, the set main part is not reset, and processing moves to image processing for the next frame with the setting of the main part maintained.

[0048] As described above, the imaging device 1 according to this embodiment detects the face and / or upper body of a person who is a subject in a captured image, and prioritizes the face as the main body part when the search area overlaps with the face area. Even if the face is not set as the main body part and the area obtained by excluding the reduced area obtained by reducing the face detection area overlaps with the search area, the imaging device 1 does not set the face as the main body part. However, when the reduced area overlaps with the search area, the imaging device 1 sets the face as the main body part. Thus, while the face is not set as the main body part, the imaging device 1 reduces the face detection area and determines the main body part, thereby reducing the phenomenon of the main body part frequently switching. Note that the detected body parts are not limited to the face and upper body of the subject; the subject's head, torso, or any other body part may be detected, and the number of detected body parts may be changed as appropriate.

[0049] Next, a specific example of image processing by the imaging device 1 according to this embodiment will be described. First, FIGS. 3A and 3B schematically show how a main part is set in an imaging device according to the prior art. In the examples of FIGS. 3A and 3B, the face detection area is not reduced when determining the main part of a captured image. FIG. 3A shows an example of a subject 301 depicted in a captured image. FIG. 3A shows a state in which a search area 302 overlaps with a face detection area 303 and an upper body detection area 304. In this case, the face of the subject 301 is set as the main part. In addition, in the case of FIG. 3A, a face frame of the same position and size as the face detection area 303 is displayed in the imaging device, and a frame for the upper body is not displayed.

[0050] Fig. 3B shows an example of a state in which search area 302 has moved from the state shown in Fig. 3A due to a user's operation of the imaging device, such as camera shake. Fig. 3B shows a state in which search area 302 does not overlap face detection area 303, but overlaps upper body detection area 304. In this case, the upper body of subject 301 is set as the main body part. In Fig. 3B, the imaging device displays a frame for the upper body in the same position and size as upper body detection area 304, but does not display a frame for the face.

[0051] As described above, in imaging devices using conventional technology, the subject depicted in the captured image is likely to switch between the state shown in FIG. 3A and the state shown in FIG. 3B due to the influence of subject movement, user hand shake, and other factors. As a result, flickering occurs in the displayed image due to a change in the display frame accompanying the change in the main part of the subject. Furthermore, in imaging devices, the positional fluctuations of each part can cause severe flickering depending on the degree of subject movement, user hand shake, and other factors. When flickering becomes severe, the focus becomes unstable during AF processing, and the display of the AF target area notified to the user frequently switches, raising concerns about a deterioration in the visibility of the image on the display screen.

[0052] 4A to 4C are schematic diagrams illustrating the setting of a main part in an image captured by the imaging device 1 according to this embodiment. 4A shows an example of the face detection area 405 of the subject 401. FIG. 4A shows a state in which the upper body of the subject 401 is set as the main body part. In FIG. 4A, in determining the main body part, the face detection area is reduced (area 405 in the figure), and overlap with the search area 402 is determined. In FIG. 4A, the search area 402 and the reduced face detection area 405 do not overlap. As a result, the image capture device 1 displays a frame for the upper body in the same position and size as the upper body detection area 404, and does not display a frame for the face. Note that the frame for the upper body displayed by the display unit 171 may be displayed in the same display format as the detection area 404, or may be displayed in a different display format, such as a dotted line or a blinking line.

[0053] Next, FIG. 4B shows an example of a state in which search area 402 has moved upward from the state shown in FIG. 4A due to a user's operation of the imaging device, such as camera shake. In FIG. 4B, similar to FIG. 4A, the overlap between reduced face detection area 405 and search area 402 is determined in the main body determination. In FIG. 4B, search area 402 and reduced face detection area 405 overlap. As a result, in imaging device 1, reduced face detection area 405 is restored to its pre-reduction size (area 403 in the figure), and a face frame is displayed in the same position and size as face detection area 403 before reduction, with no frame for the upper body displayed. The face frame displayed by display unit 171 may be displayed in the same display format as detection area 403, or in a different display format, such as solid or blinking.

[0054] Next, FIG. 4C shows an example of a state in which search area 402 has moved downward from the state shown in FIG. 4B due to a user's operation of the imaging device, such as camera shake. Because the face of subject 401 has already been set as the main body part in the state shown in FIG. 4B, in the state shown in FIG. 4C, imaging device 1 does not reduce the face detection area in the main body part determination, but determines whether face detection area 403 before reduction overlaps with search area 402. In FIG. 4C, search area 402 and face detection area 403 overlap. Therefore, in imaging device 1, a frame for the face is displayed, but a frame for the upper body is not displayed, from the state shown in FIG. 4B to the state shown in FIG. 4C. Therefore, according to this embodiment, the main body part does not change from the state shown in FIG. 4B to the state shown in FIG. 4C, and flickering associated with the change in display frame on display unit 171 does not occur.

[0055] Therefore, with image capture device 1 according to this embodiment, for a subject's face that is preferentially set as the main portion in a captured image, the face detection area is reduced and main portion determination is performed while the face is not set as the main portion. As a result, in the examples of FIGS. 4A to 4C , when search area 402 overlaps with reduced face detection area 405, the face is set as the main portion. Thereafter, while search area 402 overlaps with original detection area 403 before reduction, the state in which the face is set as the main portion continues. As a result, with image capture device 1, after the face is set as the main portion and a face display frame is displayed on display unit 171, AF processing is continuously performed on the face until the face frame and the search area frame separate, allowing the user to intuitively operate the subject depicted in the image.

[0056] Next, modified examples of the first embodiment will be described. In the following description of each modified example, the same configurations and processes as those of the imaging device 1 according to the first embodiment will be denoted by the same reference numerals, and detailed description thereof will be omitted. Furthermore, each modified example below can also be implemented in combination with other modified examples and the above-described embodiment.

[0057] (Variation 1) In the above embodiment, it is assumed that the subject is a person, but the subject is not limited to this. For example, the subject may be an animal or a vehicle. FIG. 5A shows an example in which the subject is a dog 501 as an example of an animal. FIG. 5B shows an example in which the subject is a car 511 as an example of a vehicle.

[0058] As shown in FIG. 5A, when a dog 501 is depicted in an acquired image, the image capturing device 1 performs the above process to obtain a search area 502, a detection area 503 for the dog's face (head), and a complete image of the dog. In addition, the image capturing device 1 uses a detection area 505 obtained by reducing the dog's face detection area 503 to determine whether it overlaps with the search area 502. Here, the search area 502, the face detection area 503, the whole body detection area 504, and the reduced detection area 505 correspond to the search area 402, the detection areas 403, 404, and 405 in the first embodiment, respectively.

[0059] Then, by executing the above-described processes in the first embodiment, the imaging device 1 sets the face of dog 501 as the main body part when search area 502 and reduced detection area 505 overlap. After the face is set as the main body part, the state in which the face is set as the main body part continues as long as search area 502 overlaps with face detection area 503 before reduction. Therefore, the main body part does not change until search area 502 no longer overlaps with detection area 503, and flickering associated with switching of the display frame on display unit 171 does not occur.

[0060] 5B , when an automobile 511 is depicted in an acquired image, the imaging device 1 uses a search area 512, a detection area 513 for a front door that is part of the automobile, and a detection area 514 for the entire automobile through the above processing. Furthermore, the imaging device 1 determines whether the detection area 513 for the automobile's front door overlaps with the search area 512 using a detection area 515 that is a reduced version of the detection area 513. Here, the search area 512, the detection area 513 for the front door, the entire detection area 514, and the reduced detection area 515 correspond to the search area 402, the detection areas 403, 404, and 405 in the first embodiment, respectively.

[0061] Then, by executing the above-described processes in the first embodiment, the imaging device 1 sets the front door of the automobile 511 as the main part when the search area 512 and the reduced detection area 515 overlap. After the front door is set as the main part, the state in which the front door is set as the main part continues as long as the search area 512 overlaps with the detection area 513 of the front door before it is reduced. Therefore, the main part does not change until the search area 512 no longer overlaps with the detection area 513, and flickering accompanying the change of the display frame on the display unit 171 does not occur.

[0062] In the above example, the face of dog 501 and the front door of car 511 are merely examples of parts that are set as main parts, and other parts of dog 501 and car 511 may be used as parts that are set as main parts.

[0063] (Variation 2) In the first embodiment, two detection sites were used, but three or more detection sites may be used. In the imaging device 1 according to this modification, when three or more parts are detected, a priority for setting the main part is set hierarchically for each part, and the area of ​​a part higher than the part currently set as the main part is reduced to determine the main part.

[0064] The processing executed by the imaging device 1 according to this modification will be described with reference to Fig. 6. Steps S601 and S602 correspond to steps S201 and S202 in the first embodiment, respectively.

[0065] Next, in step S603, part detection unit 141 performs a process of detecting parts of the subject on the image acquired in step S202. In this modification, part detection unit 141 detects multiple parts of the subject. The parts to be detected include the face, upper body, lower body, hands, and feet of the subject. The parts detected by part detection unit 141 may be changed as appropriate. The result of detection of the part of the subject by part detection unit 141 is sent to camera control unit 131.

[0066] Next, in step S604, the camera control unit 131 determines whether or not the detection of the subject's body part has been successful based on the detection result in step S603. If the camera control unit 131 determines that the subject's body part has been detected in the image, that is, that the detection of the subject's body part has been successful (S604: YES), the process proceeds to step S605. On the other hand, if the camera control unit 131 determines that the subject's body part has not been detected in the image, that is, that the detection of the subject's body part has failed (S604: NO), the process proceeds to step S611.

[0067] In step S605, main part setting section 151 sets an area to be used for setting the main part, based on the part detected in the image acquired in step S602. In the present embodiment, as an example, main part setting section 151 sets the detection area of ​​the part detected by part detection section 141 in step S603 as the area to be used for setting the main part.

[0068] In step S606, the main body part setting unit 151 sets a priority for setting each body part detected in step S603 as a main body part. The main body part setting unit 151 is a priority setting unit that sets a priority for each of two or more detected body parts as a main body part. As an example, a hierarchical priority is set for each detected body part, and the higher the hierarchy to which the priority is set, the higher the priority is set as a main body part. In this modified example, as an example, it is assumed that the subject is a person, and that higher hierarchy priorities are set for the subject's lower body, upper body, and face, in that order. Note that the priority setting may be performed based on any condition, such as setting a higher priority to the area indicating the body part detected in step S603, starting with the smallest size.

[0069] In step S607, the main part setting unit 151 determines whether the search area overlaps with multiple areas among the areas of each part detected in step S603 in the image. If the main part setting unit 151 determines that the search area overlaps with multiple area areas (S607: YES), the process proceeds to step S608. On the other hand, if the main part setting unit 151 determines that the search area does not overlap with multiple area areas (S607: NO), the process proceeds to step S610.

[0070] In step S608, the main part setting unit 151 determines whether or not there is a part for which a higher priority is set than the currently set main part, among the priorities set in step S606.

[0071] In this modified example, three body parts are detected from the subject: the lower body, the upper body, and the face. A higher priority is set for the upper body than for the lower body, and a higher priority is set for the face than for the upper body. Therefore, for example, if the main body part is currently set to the lower body or the upper body, there is a body part with a higher priority (the upper body for the lower body, and the face for the upper body). Therefore, the main body part setting unit 151 identifies a body part with a higher priority and proceeds with the process from step S608 to step S609. On the other hand, for example, if the main body part is currently set to the face, there is no body part with a higher priority, so the main body part setting unit 151 proceeds with the process from step S608 to step S610.

[0072] In step S609, the camera control unit 131 reduces the area of ​​the part identified as the part with the higher priority in step S607 within the image.

[0073] Next, in step 610, the main part setting unit 151 sets the main part based on the area of ​​the part that overlaps with the search area. Specifically, if two or more areas among a plurality of areas that respectively indicate a plurality of parts in the image overlap with the search area, the main part setting unit 151 sets two or more areas. Of the two or more parts corresponding to each of the above regions, the part with the highest priority is set as the main part. Furthermore, the main part setting unit 151 sets the part identified as a part with a higher priority in step S608 as the main part based on the overlap between the search area and the reduced area reduced in step S609. As a result, when a reduced area obtained by reducing the area of ​​another part with a higher priority than the part currently set as the main part overlaps with the search area, the main part setting unit 151 sets the part corresponding to the reduced area as the main part.

[0074] 4A to 4C, in step S603, the lower body, upper body, and face of subject 401 are detected, and in step S605, detection areas 403, 404, and 406 to be used for main body part determination are set corresponding to each part. If search area 402 overlaps upper body detection area 404 and lower body detection area 406, main body setting unit 151 sets the upper body, which has a higher priority, as the main body. If the face is not set as the main body, detection area 405, which is a reduced area obtained by reducing face detection area 403, is set, and if search area 402 overlaps reduced detection area 405, main body setting unit 151 sets the face as the main body. Since the face of subject 401 has already been set as the main body in the state of FIG. 4B, in the state of FIG. 4C, imaging device 1 does not reduce the face detection area in the main body part determination, and instead determines whether face detection area 403 before reduction overlaps with search area 402. In Fig. 4C, search area 402 and face detection area 403 overlap. For this reason, in imaging device 1, a state in which the frame of the face is displayed but the frame of the upper body is not displayed continues from the state in Fig. 4B to the state in Fig. 4C. Therefore, according to this embodiment, there is no change in the main body part from the state in Fig. 4B to the state in Fig. 4C, and no flickering occurs due to the change in the display frame on display unit 171.

[0075] Therefore, in this modification, after the face, which has the highest priority among the face, upper body, and lower body, is set as the main body part and a display frame for the face is displayed on the display unit 171, AF processing is continuously performed on the face until the displayed face frame and the search area frame separate. Therefore, as in the first embodiment, the user can intuitively operate the image capturing device 1 on the subject depicted in the image.

[0076] In step S611, the main part setting unit 151 sets "no main part." As a result, no main part is set in the captured image acquired in step S602. Then, the camera control unit 131 advances the process to step S215.

[0077] The processes from step S215 to step S217 are the same as those in the first embodiment, and therefore detailed description thereof will be omitted here.

[0078] While the present invention has been described in detail above based on preferred embodiments, it is not limited to these specific embodiments, and various modifications within the scope of the present invention are also encompassed within the scope of the present invention. Parts of the above-described embodiments may be combined as appropriate. Furthermore, the present invention also encompasses a case in which a software program implementing the functions of the above-described embodiments is supplied to a system or device having a computer capable of executing the program, either directly from a storage medium or via wired or wireless communication, and the program is executed. Therefore, the program code itself supplied to and installed on a computer to implement the functional processing of the present invention also embodies the present invention. In other words, the computer program itself for implementing the functional processing of the present invention is also encompassed within the present invention. In this case, the form of the program is not important, as long as it has the program functionality, such as object code, a program executed by an interpreter, or script data supplied to an OS. Examples of storage media for providing the program include magnetic storage media such as hard disks and magnetic tapes, optical / magneto-optical storage media, and non-volatile semiconductor memory. Furthermore, a method for providing the program includes storing the computer program implementing the present invention on a server on a computer network and transmitting the program to a connected server. Another possible method is for a client computer to download and program a computer program.

[0079] The various controls described above may or may not be performed by a single piece of hardware (e.g., a processor or circuit). The entire device may be controlled by multiple pieces of hardware (e.g., multiple processors, multiple circuits, or a combination of one or more processors and one or more circuits) sharing the processing.

[0080] The above processor is a processor in the broad sense, and includes general-purpose processors and dedicated processors. General-purpose processors include, for example, CPUs (Central Processing Units), MPUs (Micro Processing Units), and DSPs (Digital Signal Processors). Dedicated processors include, for example, GPUs (Graphics Processing Units), ASICs (Application Specific Integrated Circuits), and PLDs (Programmable Logic Devices). Programmable logic devices include, for example, FPGAs (Field Programmable Gate Arrays) and CPLDs (Complex Programmable Logic Devices).

[0081] Although the embodiments of the present invention have been described in detail, the present invention is not limited to these specific embodiments, and various forms within the scope of the gist of the present invention are also included in the present invention. Furthermore, each of the above-described embodiments merely represents one embodiment of the present invention, and each embodiment can be combined as appropriate.

[0082] (Other embodiments) The present invention can also be realized by a process in which a program that realizes one or more 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 the computer of the system or device read and execute the program, or by a circuit that realizes one or more functions.

[0083] The disclosure of this embodiment includes the following configuration, method, and program. (Configuration 1) an acquisition means for acquiring an image of a subject; a detection means for detecting a first region and a second region of the subject from the image; an area setting means for setting an arbitrary area within the image as a search area; a target setting means for setting either the first region or the second region as a target for image processing in accordance with an overlap between the region indicating the first region and the region indicating the second region detected by the detection means and the search region; and The target setting means, in a state where the first region is not set as the target, Even if an area obtained by excluding a reduced area obtained by reducing the area indicating the first part from the area indicating the first part overlaps with the search area, the first part is not set as the target, An imaging device, characterized in that, when the reduced area overlaps with the search area, the first part is set as the target. (Configuration 2) The imaging device described in configuration 1, characterized in that the target setting means sets the first part as the target when both the detected area of ​​the first part and the detected area of ​​the second part overlap with the search area. (Configuration 3) The target setting means sets a region of the detected first part and a region of the detected second part. 3. The imaging device according to configuration 1 or 2, wherein if neither of the first and second regions overlaps with the search region, the first region is set as the target. (Configuration 4) the image processing is a focusing process, the target setting means sets the search area as the target when the first region and the second region are not set as the target; 4. The imaging device according to any one of configurations 1 to 3. (Configuration 5) The imaging device described in configuration 4, characterized in that the target setting means sets the search area as the target when the first part or the second part is set as the target and the area of ​​the first part or the second part set as the target does not overlap with the search area. (Configuration 6) 6. The imaging device according to any one of configurations 1 to 5, further comprising a display means for displaying a frame corresponding to the part set as the target out of the first part and the second part. (Configuration 7) The imaging device according to any one of configurations 1 to 6, characterized in that the subject is a person, the first part is the face or head of the person, and the second part is the upper body or torso of the person. (Configuration 8) 7. The imaging device according to any one of configurations 1 to 6, wherein the subject is an animal, the first part is the face of the animal, and the second part is the entire body of the animal. (Configuration 9) 7. The imaging device according to any one of configurations 1 to 6, wherein the subject is a vehicle, the first portion is a part of the vehicle, and the second portion is the entire vehicle. (Configuration 10) an acquisition means for acquiring an image of a subject; a detection means for detecting two or more parts of the subject from the image; an area setting means for setting an arbitrary area within the image as a search area; a target setting means for setting one of the two or more regions as a target for image processing in accordance with an overlap between the region indicating each of the two or more regions detected by the detection means and the search region; a priority setting means for setting priorities for the two or more regions detected by the detection means with respect to the setting of the target; and When two or more areas among a plurality of areas respectively indicating a plurality of body parts overlap with the search area, the target setting means sets the body part having the highest priority among two or more body parts respectively corresponding to the two or more areas as the target; The target setting means, in a state where another part having a higher priority than the part set as the target is not set as the target, Even if an area obtained by excluding a reduced area obtained by reducing the area indicating the other part overlaps with the search area, the other part is not set as the target, When the reduced area overlaps with the search area, the other part is set as the target. An imaging device characterized by: (Configuration 11) 11. The imaging device according to configuration 10, wherein the priority is set in ascending order of the area showing each of the two or more parts. (Method 1) an acquisition step of acquiring an image of the object; a detecting step of detecting a first region and a second region of the subject from the image; a region setting step of setting an arbitrary region within the image as a search region; a target setting step of setting either the first region or the second region as a target for image processing according to an overlap between the region indicating the first region and the region indicating the second region detected by the detection step and the search region; and The target setting step includes: Even if an area obtained by excluding a reduced area obtained by reducing the area indicating the first part from the area indicating the first part overlaps with the search area, the first part is not set as the target, A control method for an imaging device, comprising: setting the first part as the target when the reduced area overlaps the search area. (Method 2) an acquisition step of acquiring an image of the object; a detecting step of detecting two or more parts of the subject from the image; a region setting step of setting an arbitrary region within the image as a search region; a target setting step of setting one of the two or more regions as a target for image processing according to an overlap between the region indicating each of the two or more regions detected by the detection step and the search region; a priority setting step of setting priorities regarding the setting of the target for the two or more parts detected by the detection step; and In the target setting step, when two or more areas among a plurality of areas respectively indicating a plurality of parts overlap with the search area, a part having the highest priority among two or more parts corresponding to the two or more areas respectively is set as the target; The target setting step is performed in a state where another part having a higher priority than the part set as the target is not set as the target. Even if an area obtained by excluding a reduced area obtained by reducing the area indicating the other part overlaps with the search area, the other part is not set as the target, When the reduced area overlaps with the search area, the other part is set as the target. 10. A method for controlling an imaging device comprising: (program) 12. A program for causing a computer to function as each of the means of the imaging device according to any one of configurations 1 to 11. [Explanation of symbols]

[0084] 1 imaging device, 131 camera control unit, 141 part detection unit, 150 search area setting unit, 151 main part setting unit

Claims

1. an acquisition means for acquiring an image of a subject; a detection means for detecting a first portion and a second portion of the subject from the image; an area setting means for setting an arbitrary area within the image as a search area; a target setting means for setting either the first region or the second region as a target for image processing in accordance with an overlap between the region indicating the first region and the region indicating the second region detected by the detection means and the search region; and The target setting means, in a state where the first portion is not set as the target, Even if an area obtained by excluding a reduced area obtained by reducing the area indicating the first part from the area indicating the first part overlaps with the search area, the first part is not set as the target, When the reduced area overlaps with the search area, the first portion is set as the target.

2. 2. The imaging device according to claim 1, wherein the target setting means sets the first part as the target when both the detected area of ​​the first part and the detected area of ​​the second part overlap with the search area.

3. 2. The imaging device according to claim 1, wherein the target setting means sets the first part as the target when neither the detected area of ​​the first part nor the detected area of ​​the second part overlaps with the search area.

4. the image processing is a focusing process, the target setting means sets the search area as the target when the first region and the second region are not set as the target; 2. The imaging device according to claim 1.

5. The imaging device of claim 4, characterized in that the target setting means sets the search area as the target when the first part or the second part is set as the target and the area of ​​the first part or the second part set as the target does not overlap with the search area.

6. 2. The imaging device according to claim 1, further comprising a display unit that displays a frame corresponding to the region set as the target, out of the first region and the second region.

7. 2. The imaging device according to claim 1, wherein the subject is a person, the first part is the face or head of the person, and the second part is the upper body or torso of the person.

8. 2. The imaging device according to claim 1, wherein the subject is an animal, the first region is a face of the animal, and the second region is the entire body of the animal.

9. 2. The imaging device according to claim 1, wherein the subject is a vehicle, the first portion is a part of the vehicle, and the second portion is the entire vehicle.

10. an acquisition means for acquiring an image of a subject; a detection means for detecting two or more parts of the subject from the image; an area setting means for setting an arbitrary area within the image as a search area; a region indicating each of the two or more parts detected by the detection means; a target setting means for setting one of the two or more regions as a target for image processing in accordance with an overlap with the region; a priority setting means for setting priorities for the two or more regions detected by the detection means with respect to the setting of the target; and When two or more areas among a plurality of areas respectively indicating a plurality of body parts overlap with the search area, the target setting means sets the body part having the highest priority among two or more body parts respectively corresponding to the two or more areas as the target; The target setting means, in a state where another part having a higher priority than the part set as the target is not set as the target, Even if an area obtained by excluding a reduced area obtained by reducing the area indicating the other part overlaps with the search area, the other part is not set as the target, When the reduced area overlaps with the search area, the other part is set as the target. An imaging device characterized by:

11. 11. The imaging device according to claim 10, wherein the priority is set in ascending order of the area indicating each of the two or more parts.

12. an acquisition step of acquiring an image of the object; a detecting step of detecting a first region and a second region of the subject from the image; a region setting step of setting an arbitrary region within the image as a search region; a target setting step of setting either the first region or the second region as a target for image processing in accordance with an overlap between the region indicating the first region and the region indicating the second region detected by the detection step and the search region; and The target setting step includes: Even if an area obtained by excluding a reduced area obtained by reducing the area indicating the first part from the area indicating the first part overlaps with the search area, the first part is not set as the target, A control method for an imaging device, comprising: setting the first portion as the target when the reduced region overlaps the search region.

13. an acquisition step of acquiring an image of the object; a detecting step of detecting two or more parts of the subject from the image; a region setting step of setting an arbitrary region within the image as a search region; a target setting step of setting one of the two or more regions as a target for image processing according to an overlap between the search area and an area indicating each of the two or more regions detected by the detection step; a priority setting step of setting priorities regarding the setting of the target for the two or more parts detected by the detection step; and In the target setting step, when two or more areas among a plurality of areas respectively indicating a plurality of parts overlap with the search area, a part having the highest priority among two or more parts corresponding to the two or more areas respectively is set as the target; The target setting step is performed in a state where another part having a higher priority than the part set as the target is not set as the target. Even if an area obtained by excluding a reduced area obtained by reducing the area indicating the other part overlaps with the search area, the other part is not set as the target, When the reduced area overlaps with the search area, the other part is set as the target.

10. A method for controlling an imaging device comprising:

14. A program for causing a computer to function as each of the means of the imaging device according to any one of claims 1 to 11.

Images