JP6335520B2 - IMAGING DEVICE, IMAGING DEVICE CONTROL METHOD, AND IMAGING DEVICE CONTROL PROGRAM - Google Patents

Description

  The present invention relates to an imaging apparatus having a zoom function, a control method thereof, and the like.

  2. Description of the Related Art Conventionally, there has been an imaging apparatus having a function of driving a zoom lens to perform optical scaling (optical zoom) and a function of enlarging a part of a captured image to perform electronic scaling (electronic zoom). Are known. Patent Document 1 discloses an imaging apparatus having a framing support zoom function (FA zoom function) as a function of quickly capturing a subject when the subject is out of frame. According to the configuration of Patent Document 1, when the start of FA zoom is instructed, the zoom position is zoomed out in the wide-angle direction, and when the end of the FA zoom function is instructed, control is performed to zoom in to the zoom position at the start of FA zoom. I do.

  There is also known an imaging apparatus having an auto zoom function that automatically changes the zoom position according to subject detection information. Patent Document 2 discloses a configuration of a camera equipped with an auto-zoom function that keeps the size of a subject constant. Further, Patent Document 2 discloses a method that makes it difficult to frame out a subject by slowing the zoom speed when the distance from the center of the screen to the subject is far within the screen or when the size of the subject is large. Yes.

JP 2012-60595 A JP2011-259285A

  However, in the configuration disclosed in Patent Document 2, when the photographer's framing operation is delayed when the subject moves toward the outside of the screen, or when the camera is fixed to a tripod, the subject is a frame. There is a risk of going out. Further, when the zoom is in the telephoto state, the possibility of being out of frame due to camera shake or the like increases. In order to solve such problems, an auto zoom function for maintaining the size of the subject and an auto zoom function for preventing the frame out by zooming out when the subject is detected around the screen are performed in parallel. It is conceivable to have a configuration that functions. In such a configuration, if the two zoom functions are not switched at an appropriate timing, the subject may accidentally frame out due to the auto zoom operation, or the desired size may not be maintained.

  An object of the present invention is to provide an imaging apparatus capable of achieving both zoom control for preventing the subject from being out of frame and zoom control for maintaining the size of the subject.

In order to achieve the above object, according to a first aspect of the present invention, an operation unit for a user to instruct a zoom operation, subject detection means for detecting a subject from an image, and a zoom operation according to an operation of the operation unit. and control means for controlling, the control means executes a first mode for controlling the zoom operation based on the position of the object, and a second mode for controlling the zoom operation based on the size of the subject Preferably, the control means limits the execution of the second mode from the time when the zoom operation to the wide angle side is performed to the time when the zoom operation to the telephoto side is completed in the first mode. It is characterized by.

According to a second aspect of the present invention, there is provided a control method for an imaging apparatus having an operation unit for a user to instruct a zoom operation, a subject detection step for detecting a subject from an image, and a zoom operation according to an operation of the operation unit A first mode for controlling the zoom operation based on the position of the subject and a second mode for controlling the zoom operation based on the size of the subject in the control step. It is possible to limit the execution of the second mode from the time when the zoom operation to the wide angle side is performed in the first mode to the time when the zoom operation to the telephoto side is completed .

  According to the present invention, it is possible to achieve both zoom control for preventing the subject from being out of frame and zoom control for maintaining the size of the subject.

It is a block diagram which shows the structural example of the digital camera which concerns on embodiment of this invention. It is the figure which illustrated the relationship between a focal distance and a focus lens position for every subject distance. It is the figure which illustrated the angle of view in the subject search state and the angle of view in the shooting preparation state. It is a figure explaining the process for preventing the frame out of the subject (thing) outside the screen. It is a figure explaining the process for preventing the frame out of the screen of a subject (person). It is a figure explaining the process for preventing the size change in the screen of a to-be-photographed object (person). It is a flowchart explaining the flow of a process of FA zoom function. FIG. 8 is a flowchart illustrating the flow of processing of the FA zoom function together with FIG. 7. It is a flowchart explaining a subject designation process. It is a flowchart explaining FA zoom-out operation | movement and FA zoom-in operation | movement. It is a flowchart explaining zoom stop determination. It is a figure explaining the process for preventing the malfunctioning by the change of the direction of a to-be-photographed object (person).

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Note that the function realized by the present embodiment is a framing support zoom function that supports framing by the user, and is referred to as a framing assist zoom function (hereinafter abbreviated as FA zoom function) for convenience.

  FIG. 1 is a block diagram illustrating a configuration example of a digital camera 100 as an example of an imaging apparatus according to the present embodiment. The digital camera 100 is configured to be able to execute the FA zoom function.

  The lens barrel 101 holds a lens group therein. The zoom lens 102 adjusts the focal length by moving in the optical axis direction, and optically changes the angle of view (moves the zoom position). The focus lens 103 adjusts the focus by moving in the optical axis direction. The anti-vibration lens 104 is a correction lens that corrects image blur caused by camera shake. The aperture and shutter 105 are configured to be able to adjust the amount of light, and are used for exposure control. In the present embodiment, the digital camera 100 is an imaging device in which the lens barrel 101 and the camera body are integrally configured, but is not limited to this. The present embodiment is also applicable to an imaging system that includes a camera body and an interchangeable lens that can be attached to and detached from the camera body.

  The light that has passed through the lens barrel 101 is received by an imaging device 106 that includes a CCD (charge coupled device) or a CMOS (complementary metal oxide semiconductor). The imaging element 106 generates an imaging signal by converting a subject image into an electrical signal by photoelectric conversion. The imaging signal is input to the image processing circuit 107. The image processing circuit 107 performs various processing such as pixel interpolation processing and color conversion processing on the input image pickup signal, and outputs image data (image data after various processing) to the image memory 108. The image memory 108 is a storage means that includes a DRAM (Dynamic Random Access Memory), an SRAM (Static Random Access Memory), and the like.

  The display unit 109 includes a TFT type LCD (Thin Film Transistor Driven Liquid Crystal Display) and the like, and displays a captured image (image data). The display unit 109 displays specific information (for example, shooting information and an FA zoom frame described later) along with the shot image. By displaying information such as live view, an electronic viewfinder (EVF) function for the photographer to adjust the angle of view is realized.

  The aperture shutter drive unit 110 calculates an exposure control value (aperture value and shutter speed) based on luminance information obtained by image processing in the image processing circuit 107, and drives the aperture and shutter 105 based on the calculation result. To do. Thereby, AE (automatic exposure) control is performed. The anti-vibration lens driving unit 111 calculates an amount of shake applied to the digital camera 100 based on information from an angular velocity sensor such as a gyro sensor, and drives the anti-vibration lens 104 so as to cancel (reduce) the shake amount.

  The focus lens driving unit 112 drives the focus lens 103. In the present embodiment, the digital camera 100 performs AF (autofocus) control using a contrast method. For this reason, the focus lens driving unit 112 drives the focus lens 103 so that the subject is in focus based on the focus adjustment information (contrast evaluation value) of the photographing optical system obtained by the image processing of the image processing circuit 107. However, the present embodiment is not limited to this, and AF control using a plurality of methods such as AF control other than the contrast method such as the phase difference AF method or a combination of the contrast method and another method is performed. You may comprise.

  The zoom lens driving unit 113 drives the zoom lens 102 in accordance with a zoom operation instruction. The operation unit 117 includes a zoom lever, a zoom button, or the like as a zoom operation member for the photographer to instruct the camera to perform zooming. Based on the operation amount and operation direction of the zoom operation member used for the zoom instruction operation, the system control unit 114 calculates the zoom drive speed and drive direction, and the zoom lens 102 is moved along the optical axis according to the calculation result.

  The image data generated by the shooting operation is sent to the recording unit 116 via the interface unit (hereinafter referred to as I / F unit) 115 and recorded. The image data is recorded on an external recording medium such as a memory card used by being attached to the digital camera 100, a nonvolatile memory 118 built in the digital camera 100, or both.

  In addition to the zoom operation member, the operation unit 117 includes a release switch for instructing start of photographing, an FA zoom operation switch for instructing start and end of an FA zoom function, and the like. A signal from the operation unit 117 is sent to the system control unit 114 described later. In addition to program data and image data, the memory 118 stores setting information of the digital camera 100 and information such as a zoom-in position in an FA zoom function described later. Here, the zoom-in position is a zoom return position which is a target when zooming in at the end of the FA zoom, and details thereof will be described later.

  The system control unit 114 is configured to include an arithmetic device such as a CPU (Central Processing Unit), and controls the entire digital camera 100 by sending a control command to each unit in accordance with a photographer's operation. The system control unit 114 executes various control programs stored in the memory 118, for example, programs for performing control of the image sensor 106, AE / AF control, zoom control (including FA zoom processing), and the like.

  Next, control related to the FA zoom function in the system control unit 114 will be described. As shown in FIG. 1, the system control unit 114 includes a CZ control unit 119, an electronic zoom control unit 120, an FA zoom frame control unit 121, an FA zoom control unit 122, and a subject detection unit 123. .

  In order to maintain the in-focus state when the angle of view is changed by the optical zoom, in the case of a rear focus type lens barrel such as the lens barrel 101, the focus lens 103 is moved to an appropriate focus position according to the position of the zoom lens 102. Must be moved. Such control is called computer zoom (CZ) control. FIG. 2 is a relationship diagram between the focal length of the zoom lens and the focus position for each subject distance. In FIG. 2, the relationship between the focal length of the zoom lens and the in-focus focus position is graphed as a data table indicating each distance to the subject. In the present embodiment, this table is referred to as a focus cam table. In FIG. 2, the horizontal axis indicates the focal length corresponding to the zoom position, and the vertical axis indicates the focus position. Next to each graph line, the distance from the digital camera 100 to the subject (subject distance) is shown.

  The system control unit 114 controls the focus lens driving unit 112 when performing AF control, and performs a scanning operation by moving the focus lens 103 within a predetermined range. A focus position which is a focal point is detected by a known method using a contrast evaluation value or the like obtained during this operation. The subject distance can be measured by referring to the focus cam table using the zoom position and the focus position at that time.

  The digital camera 100 has an optical zoom function and an electronic zoom function. The CZ control unit 119 and the zoom lens driving unit 113 perform optical zoom. The CZ control unit 119 detects the zoom position of the zoom lens 102 at every predetermined control period during the zoom operation. Then, the CZ control unit 119 drives the focus lens 103 so as to follow the focus cam table at the subject distance measured by the AF control according to the zoom position. This makes it possible to perform an optical zoom operation while maintaining the in-focus state.

  On the other hand, the electronic zoom control unit 120 and the image memory 108 perform electronic zoom. The electronic zoom control unit 120 implements an electronic zoom function by cutting out a target area from the image data transferred to the image memory 108. In addition, the electronic zoom control unit 120 realizes a smooth electronic zoom display by displaying the display unit 109 while gradually increasing the range to be extracted at the frame rate period of the image to be captured by the image sensor 106.

  The subject detection unit 123 detects a desired subject region from the image data stored in the image memory 108. In the present embodiment, a subject detection method (face detection processing, color detection processing) for detecting a subject (face or object) based on face information or color information included in image data will be described.

  The face detection process is a process for detecting a face area existing in image data by a known algorithm. For example, the subject detection unit 123 extracts a feature amount from a square partial region on the image data, and compares the feature amount with a facial feature amount prepared in advance. If the correlation between the two exceeds a predetermined threshold, the subject detection unit 123 determines that the partial area is a face area. By repeating this determination while changing the combination of the size, the arrangement position, and the arrangement angle of the partial areas, various face areas existing in the image data can be detected. Further, the orientation of the face can be detected by determining at which position in the face area the area indicating the feature amount such as eyes, nose, and hair is located.

  In the color detection process, the color information of the subject area designated according to the subject designation method described later is stored as a characteristic color. The color detection process is executed when the subject to be detected is an object (a “thing” other than a person). As the color information, RGB, luminance Y, color differences RY, BY, and the like, which are output signals from the image processing circuit 107, are used. At the time of subject detection, the subject detection unit 123 divides the image data into a plurality of partial areas, and calculates an average value of luminance and color difference for each partial area. In addition, the subject detection unit 123 compares the characteristic color information stored in advance with the color information of each region at the time of subject detection, and sets a partial region in which the difference in luminance and color difference is equal to or less than a predetermined amount as a subject region candidate. A group of partial areas adjacent to each other in this area candidate is defined as the same color area, and an area where the same color area falls within a predetermined size range is defined as a final subject area.

  The subject detection unit 123 estimates the size of the subject region on the image data by using the subject distance information measured by the CZ control unit 119 and the focal length information of the zoom lens 102 together with the face information and the color information. be able to.

  The posture detection unit 124 detects the posture of the digital camera 100 (normal position / above grip / under the grip) based on information from the acceleration sensor. The shake detection unit 125 detects the shake state of the digital camera 100 based on information such as a gyro sensor. The shake detection unit 125 detects that the gyro sensor or the like is in a hand-held state when the shake amount applied to the gyro sensor or the like is equal to or greater than a predetermined amount, and indicates that the shake detection unit 125 is fixed to a tripod or the like when the shake amount is less than the predetermined amount. To detect. The acceleration sensor and the gyro sensor used for posture detection and shaking detection may be configured to be used also as a sensor used as control information for the anti-vibration lens driving unit 111.

  Next, an overview of the FA zoom function and the FA zoom frame control unit 121 and the FA zoom control unit 122 will be described. The digital camera 100 of the present embodiment has two modes, a manual search mode and an automatic tracking mode, as modes for executing FA zoom. These two modes are modes in which the photographer operates the FA zoom operation switch when the subject is out of the frame to recapture the subject, or the camera automatically detects the subject and supports angle adjustment. It is different in whether it is. Hereinafter, an overview of the functions of each mode will be described.

  In a camera not equipped with the FA zoom function, the photographer needs to perform the following operations when the subject moves out of the frame while framing in the telephoto state and waiting for a photo opportunity. That is, first, the subject is searched after zooming out by operating the zoom operation member. Then, after searching for the subject, the angle of view is adjusted by zooming until the desired angle of view is reached again.

  On the other hand, in the digital camera 100 having the manual search mode of the FA zoom function, when the subject is lost in a state in which the angle of view is adjusted before photographing (hereinafter referred to as a photographing preparation state), the photographer switches the FA zoom operation switch. Can be operated. This FA zoom operation switch is a switch assigned for the FA zoom function, and is a member different from the zoom operation member. By pressing the FA zoom operation switch, the camera is instructed to start the FA zoom function. The FA zoom control unit 122 stores each zoom position of the electronic zoom and the optical zoom in the memory 118 in response to an FA zoom start instruction from the FA zoom operation switch. Further, the FA zoom control unit 122 instructs the CZ control unit 119 or the electronic zoom control unit 120 to zoom out in the wide-angle direction according to the processing procedure described below, and the angle of view is zoomed out from the shooting preparation state. (Hereinafter referred to as subject search state).

  Next, with reference to FIG. 3, each angle of view in the shooting preparation state and the subject search state will be described. FIG. 3 is an explanatory diagram of the angle of view in the subject search state and the angle of view in the shooting preparation state. 3A and 3D show the angle of view in the zoom-in state (shooting preparation state), and FIGS. 3B and 3C show the angle of view in the zoom-out state (subject search state). Is shown.

  When the subject is out of frame as shown in FIG. 3A, the photographer presses the FA zoom operation switch to search for the subject. While the FA zoom operation switch is pressed, the zoom-out state is maintained, and the FA zoom frame 300 indicating the zoom-in position is displayed on the display unit 109 so as to be superimposed on the image.

  When a desired subject is found in the zoom-out state (subject search state) as shown in FIG. 3B, the subject is photographed so as to fit inside the FA zoom frame 300 as shown in FIG. Perform framing. Thereafter, the photographer releases the FA zoom operation switch to instruct the FA zoom control unit 122 to end the FA zoom. At this time, the FA zoom control unit 122 performs a zoom-in operation by electronic zoom or optical zoom up to the stored zoom position (zoom-in position) in the shooting preparation state. Thereby, the optimal framing state as shown in FIG. 3D is obtained.

  As shown in FIGS. 3B and 3C, the FA zoom frame control unit 121 calculates the size indicating the angle of view in the stored shooting preparation state, and the EVF center of the display unit 109 is calculated. The FA zoom frame 300 is displayed on the screen. The size of the FA zoom frame 300 is calculated based on the zoom magnification at the time of zooming out. For example, when the subject search state is entered by zooming out from the shooting preparation state at 2 × electronic zoom magnification and 3 × optical zoom magnification, the angle of view displayed on the EVF in the subject search state is (1 / 2) A FA zoom frame with a size of (1/3) = 1/6 times is displayed. By such processing, the photographer can shoot at a desired angle of view while re-framing the subject out of the frame with a simple operation.

  Also, when shooting a scene where the subject is likely to be out of frame, such as when shooting a moving subject, frame out can be more easily prevented by the automatic tracking mode in which the camera automatically changes the zoom position. In particular, when shooting in the telephoto state, since the angle of view is narrow, there is a case where the subject is out of frame even by a slight camera movement caused by camera shake or the like.

  The digital camera 100 of the present embodiment has an automatic tracking mode with an FA zoom function. For this reason, after setting the automatic tracking mode, the subject to be photographed may be designated by performing an operation of designating the subject on the touch panel or the like. Other than touch panel operation, the subject can be specified by specifying the subject near the center when a specific button is pressed, or automatically selecting the main subject from the subjects detected by the camera. Conceivable.

  The subject detection unit 123 calculates the position and size of the subject region designated from the image memory 108 on the image data. It is possible to track the movement of the subject by continuously performing this for each sampled image data displayed as a live view. When the subject being tracked is detected in a zoom-out area to be described later or becomes larger than a predetermined size, the FA zoom control unit 122 zooms out in the wide-angle direction with respect to the CZ control unit 119 or the electronic zoom control unit 120. The instructions are given. When the subject is detected within the zoom-in area of the FA zoom frame 300 and falls within a predetermined size range, the zoom-in operation is performed to the telephoto zoom position indicated by the FA zoom frame 300. By such processing, the photographer only has to move the camera so that the subject is placed on the screen without worrying about the zoom operation. Even if the subject is about to be out of frame, the zoom position is automatically changed, so that the angle of view can be adjusted more easily. In the present embodiment, the photographer can easily perform framing by performing the zoom-out operation and the zoom-in operation in the automatic tracking mode at the optimal timing.

  Next, the start conditions for the zoom-out operation and the zoom-in operation will be described with reference to FIGS. FIG. 4 is an explanatory diagram of processing for preventing the subject (thing) from being out of the frame. FIG. 5 is an explanatory diagram of processing for preventing a subject (person) from being out of the frame.

  4 and 5, 400 is a mono tracking frame for tracking a subject (thing other than a person), and 500 is a face tracking frame for tracking a subject (person's face). In the present embodiment, when the subject is applicable to both a person and a thing, the thing tracking frame 400 and the face tracking frame 500 may be collectively referred to as a subject tracking frame. The subject tracking frame is displayed on the EVF of the display unit 109 so as to surround the subject so that the subject designated by the photographer can be seen. The position and size of the subject tracking frame on the screen are calculated by the subject detection unit 123 based on the face information and the color information, and are updated at a frame rate cycle.

  FIG. 4 is an explanatory diagram of a process for preventing the subject (airplane) from being out of the screen. FIG. 4A shows a predetermined ratio with respect to the entire angle of view (the entire screen) displayed in the EVF. The outer region is also shown as a zoom-out region ZO (outside the first region). For example, when the center point of the screen is set to 0%, the entire screen is set to 100%, and a position that is 80% of the entire screen is set as the boundary of the zoom-out area ZO, the area of 80 to 100% in the entire screen is zoomed. It becomes the out area ZO. When a part of the mono tracking frame 400a enters the zoom-out area ZO in the image, the zoom-out operation is started. Also, the zoom position before zoom movement (second zoom position, corresponding to the zoom-in angle of view) is stored in the memory 118. The zoom magnification and zoom speed during the zoom-out operation are preset according to the size and moving speed of the subject. Further, the zoom magnification and the zoom speed may be appropriately calculated according to the size and moving speed of the subject. The zoom-out operation is executed according to the magnification and zoom speed. Thereby, it is possible to effectively prevent the subject from being out of frame.

  FIG. 4B shows an angle of view (first zoom position) obtained by zooming out from the angle of view of FIG. 4A by a predetermined zoom drive amount. In FIG. 4B, an area inside a predetermined ratio with respect to the zoom-in angle of view indicated by the FA zoom frame 300 in the subject search state is shown as a zoom-in area ZI (second area). For example, when the center point of the screen is set to 0%, the FA zoom frame 300 (zoom-in angle of view) is set to 100%, and a position that is 70% of the zoom-in angle of view is set as the boundary of the zoom-in area ZI, the FA zoom frame 300 A zoom-in area ZI is an area of 0 to 70% in the whole. At this time, when the zoom-out magnification is 1/2, for example, the FA zoom frame 300 is 50% of the entire screen. Therefore, it can be said that the zoom-in area ZI is an area of 0 to 35% (= 70% × (1/2)) with respect to the entire screen. When the photographer changes the orientation of the camera so that the mono tracking frame 400b fits inside the zoom-in area ZI, the zoom-in operation starts.

  FIG. 5 is an explanatory diagram of processing for preventing a subject (person) from being out of the frame. Even when the subject is a person, the zoom-out operation starts when a part of the face tracking frame 500 enters the zoom-out area ZO, and the zoom-in operation is performed when the face tracking frame 500 falls within the zoom-in area ZI. The difference between the case where the subject is a person and the case where the subject is a person is that if the subject is a person, the moving direction can be predicted to some extent, so the zoom-out region ZO and the zoom-in region ZI only in the region of the predicted moving direction. Is to set.

  In addition, when shooting with a hand, the subject may be out of frame due to the influence of camera shake or the like. However, if the camera is out of the frame due to camera shake, the photographer can re-frame in by an operation to try to frame the subject. Here, when the zoom-out area ZO is set at the top of the screen, the face tracking frame 500 enters the zoom-out area ZO even when a person is placed near the center for shooting, and the zoom-out area ZO is unintentionally zoomed out. There is a case. Therefore, when the subject is a person and is in a handheld state, the zoom-out area ZO is not set at the top of the screen in consideration of the framing operation of the photographer.

  As described above, in the present embodiment, when the face is detected by the subject detection unit 123, the zoom-out area ZO and the zoom-in are determined in accordance with the camera posture detected by the posture detection unit 124 and the detection result by the shake detection unit 125. The area of the area ZI is dynamically changed. Here, the detection result by the shaking detection unit 125 is detection of whether or not the hand is held.

  FIG. 5A shows a zoom-out area ZO and a zoom-in area ZI that are set when the camera is held in a normal position by hand. In such a shooting scene, when the subject moves in the horizontal direction and goes out of the frame, the position of the subject in the screen moves in the horizontal direction (longitudinal direction) with respect to the screen at the normal position. Accordingly, as shown in FIG. 5A, the zoom-out area ZO and the zoom-in area ZI are arranged in a vertical band (vertical direction) with respect to the screen at the normal position. When the face tracking frame 500a enters the zoom-out area ZO, it is determined that zoom-out has started, and zoom-out is performed by a predetermined zoom magnification. When the face tracking frame 500b is included in the zoom-in area ZI, the zoom-in start is determined, and zoom-in is performed up to a zoom return position 501 by a predetermined zoom magnification. By setting the zoom-out area ZO and the zoom-in area ZI in this way, frame-out can be effectively prevented.

  FIG. 5B shows a zoom-out area ZO and a zoom-in area ZI that are set when the camera is held under the grip or in the vertical position on the grip in the same shooting scene. In this case, the zoom-out area ZO and the zoom-in area ZI are arranged in a vertical band shape in the vertical direction (longitudinal direction) with respect to the screen at the vertical position. Then, when the face tracking frame 500c enters the zoom-out area ZO, it is determined that zoom-out has started, and zoom-out is performed by a predetermined zoom magnification. When the face tracking frame 500d is included in the zoom-in area ZI, the zoom-in start is determined, and zoom-in is performed up to a zoom return position 502 by a predetermined zoom magnification. By setting the zoom-out area ZO and the zoom-in area ZI in this way, it is possible to detect the movement of the subject in the horizontal direction and effectively prevent frame-out.

  FIG. 5C shows a zoom-out area ZO and a zoom-in area ZI that are set when the detection state in the shake detection unit 125 is a fixed state. When fixed with a tripod or the like, there is no risk of frame-out due to camera shake. Furthermore, if the subject zooms in when the subject is not in the vicinity of the center of the screen, there is a risk that the operation will cause the subject to be out of the frame. Therefore, the zoom-out area ZO is set on the entire periphery of the screen, and the zoom-in area ZI is set inside the zoom-in angle of view. When the face tracking frame 500e enters the zoom-out area ZO, it is determined that the zoom-out has started, and zoom-out is performed by a predetermined zoom magnification. When the face tracking frame 500f is included in the zoom-in area ZI, the zoom-in start is determined and zoom-in is performed up to a zoom return position 503 by a predetermined zoom magnification.

  As described above, the zoom-out area ZO and the zoom-in area ZI are dynamically changed according to changes in the posture of the camera and the photographing state (hand-held state / fixed state), thereby preventing malfunction due to camera shake or the like. The frame out of the subject can be effectively prevented. Note that the zoom-out area ZO or the zoom-in area ZI may be changed in accordance with either the camera posture or the shooting state (handheld state / fixed state). Further, only one of the zoom-out area ZO and the zoom-in area ZI may be changed.

  FIGS. 6A to 6C show an example in which, when a person who is a subject approaches the camera, the camera automatically performs a zoom operation so that the ratio of the subject to the screen falls within a predetermined ratio. ing. The face tracking frame 500 is displayed so as to surround the face region as a feature region of the person who is the subject. Therefore, here, the description will be made assuming that the size of the face tracking frame 500 = the subject size.

  FIG. 6A shows the angle of view when a subject is designated according to a subject designation method described later. The size of the face tracking frame 600a at the time of subject designation is stored in the memory 118 as a reference subject size (reference size).

  FIG. 6B shows the angle of view when the subject approaches the camera without changing the zoom position from the state of FIG. For example, a size that is 150% of the size of the face tracking frame 600a that is the reference subject size is set as the start size of the zoom-out operation. When the relationship between the subject tracking frame (face tracking frame) is face tracking frame 600b> face tracking frame 600a × 150% (changes exceeding a predetermined change amount with respect to the reference size), the FA zoom control unit 122 The start of the zoom-out operation is determined.

  FIG. 6C shows an angle of view zoomed out from the angle of view 601 of FIG. 6B by a predetermined zoom magnification, and a face tracking frame 600c. Here, the predetermined zoom magnification is set to 1 / 1.5 in consideration of the rate of change (150%) from the reference subject size of the face tracking frame size when starting the zoom-out operation. Thereafter, when the subject approaches further, the subject can be kept within a predetermined ratio by zooming out further to the wide angle side. Therefore, the photographer can concentrate only on the operation of the release switch.

  On the other hand, FIGS. 6D to 6F show examples in which when the person who is the subject moves away from the camera, the camera automatically performs the zoom operation so that the ratio of the subject to the screen falls within a predetermined ratio. ing.

  FIG. 6D shows an angle of view when a subject is designated according to a subject designation method described later. The size of the face tracking frame 600d at the time of subject designation is stored in the memory 118 as a reference subject size.

  FIG. 6E shows the angle of view when the subject has moved away from the camera without changing the zoom position from the state of FIG. For example, a size that is 50% of the size of the face tracking frame 600d, which is the reference subject size, is set as the start size of the zoom-in operation. The relationship between the subject tracking frame (face tracking frame) is as follows: face tracking frame 600e <face tracking frame 600d × 50% (changes exceeding a predetermined change amount with respect to the reference size), and the face tracking frame 600e is a zoom-in area. When it is determined that it is included in the ZI, the FA zoom control unit 122 determines the start of the zoom-in operation. Here, the zoom-in area ZI is set inside the angle of view 602 zoomed in by a predetermined zoom magnification with respect to the angle of view of FIG.

  FIG. 6F shows an angle of view (corresponding to the angle of view 602) zoomed in by a predetermined zoom magnification from the angle of view of FIG. 6E, and a face tracking frame 600f. Here, the predetermined zoom magnification is set to 1 / 0.5 in consideration of the rate of change (50%) from the reference subject size of the face tracking frame size when starting the zoom-in operation.

  FIGS. 12A to 12C show that when the person who is the subject changes the orientation of the face, the ratio of the subject to the screen changes, or the zoom malfunctions when the subject is not moving. An example of preventing this is shown.

  FIG. 12A shows an angle of view and a face tracking frame 1200a when the subject is facing the front of the camera and the subject is designated according to the subject designation method described later. The size of the face tracking frame 1200a at the time of subject designation is stored in the memory 118 as a reference subject size.

  FIG. 12B shows the face tracking frame 1200b when the face of the subject is inclined from the state of FIG. The subject detection unit 123 can detect the face orientation based on the algorithm described above. In addition, the size of the face tracking frame detected by the subject detection unit 123 is smaller in the face tracking frame 1200b that is inclined with respect to the face tracking frame 1200a in the front direction. For example, when the orientation of the face tracking frame 1200a is 0 °, a detection result of 45 ° is obtained in the face tracking frame 1200b. Furthermore, it is assumed that the size relationship between the face tracking frame 1200a and the face tracking frame 1200b is obtained as follows: face tracking frame 1200a = face tracking frame 1200b × 120%. At this time, when the subject moves closer to the camera from the state of FIG. 12B or moves away from the camera, if the zoom operation is performed so as to maintain the size of the face tracking frame 1200a which is the reference size, the face orientation is changed. The size of the face tracking frame that has changed due to the amount of change (120% in this case) is too large.

  Therefore, in the present embodiment, the size of the face tracking frame is corrected by multiplying the size of the face tracking frame by a predetermined magnification in accordance with the detected face orientation. For example, in the example of FIG. 12B, the face orientation has changed by 45 ° diagonally, so the size of the face tracking frame 1200b can be corrected by multiplying the size of the face tracking frame 1200b by 1.2.

  By correcting the size of the face tracking frame in this way, the ratio of the subject to the screen is the same even if the face orientation is different from when the reference size is stored. It should be noted that the display of the face tracking frame is not changed, and only the size of the subject used for the determination of the zoom operation start is corrected, or the reference subject size stored in the memory 118 is corrected according to the face orientation. Good.

  FIG. 12C shows a face tracking frame 1200c when the face of the subject is further turned sideways from the state of FIG. The size of the face tracking frame detected by the subject detection unit 123 is smaller in the face tracking frame 1200c that is in the horizontal direction than in the face tracking frame 1200b in the oblique direction. For example, it is assumed that the subject detection unit 123 obtains a detection result that the face direction of the face tracking frame 1200c is 90 °. Furthermore, it is assumed that the relationship between the size of the face tracking frame 1200a and the face tracking frame 1200c is obtained as follows: face tracking frame 1200a = face tracking frame 1200c × 150%. Here, the size that is 67% (1 / 1.5 times) the size of the face tracking frame 1200a, which is the reference size, is set as the start size of the zoom-in operation. Then, when the size of the face tracking frame is not corrected, the zoom-in operation malfunctions just by changing the face orientation to the state of the face tracking frame 1200c as shown in FIG. In addition, the size of the subject detected by the subject detection unit 123 is large due to the feature amount of the face region being different from that of the face facing the front side. Therefore, the correction accuracy of the size of the face tracking frame in the lateral direction with respect to the size of the face tracking frame in the front direction is lowered.

  Therefore, in this embodiment, when the detected face orientation is larger than a predetermined angle, the zoom operation for preventing the size change is prohibited. Accordingly, when a face with a low detection accuracy is detected, it is possible to prevent the zoom from malfunctioning even though the subject has not moved.

  In FIG. 4 and FIG. 5, the processing for preventing frame-out when the subject is a thing or a person has been described. Further, in FIG. 6, the processing for keeping the size of the subject within a predetermined ratio when the subject is a person has been described. Even when the subject to be tracked is a thing, the zoom operation start determination for the subject size holding control shown in FIG. 6 may be performed as in the case where the subject is a person. Furthermore, FIG. 12 illustrates the processing for preventing a malfunction when the orientation of the face changes when the subject is a person.

  Next, processing of the FA zoom function will be described with reference to FIGS. 7 and 8 are flowcharts showing the overall processing of the FA zoom function. The FA zoom function in FIGS. 7 and 8 is performed based on a command from the FA zoom control unit 122 unless otherwise specified.

  First, in step S100, the FA zoom control unit 122 determines whether or not the FA zoom operation switch of the operation unit 117 is pressed. When the FA zoom operation switch is pressed, the process proceeds to step S101, and the FA zoom control unit 122 measures the pressing time of the FA zoom operation switch.

  In step S101, the FA zoom control unit 122 determines whether the FA zoom operation switch is released within a predetermined time after the FA zoom operation switch is pressed. That is, the FA zoom control unit 122 determines whether the FA zoom operation switch is long-pressed (second operation) or short-pressed (first operation), and changes the mode to be executed according to the pressing time. When the FA zoom operation switch is pressed for a long time, the process proceeds to step S121 in FIG. 8, and the FA zoom control unit 122 selects the manual search mode (third mode) and stores the selected mode in the memory 118. On the other hand, when the FA zoom operation switch is pressed shortly, the process proceeds to step S106, where the FA zoom control unit 122 selects the automatic tracking mode and stores the selected mode in the memory 118.

  When the manual search mode is stored, in step S122, the FA zoom control unit 122 stores the optical zoom position and the electronic zoom position at the start of zoom-out. Further, the FA zoom control unit 122 instructs a predetermined drive amount to the CZ control unit 119 or the electronic zoom control unit 120 to perform an FA zoom-out operation which will be described later with reference to FIG. When the FA zoom-out operation ends, the process proceeds to step S123.

  In step S123, the FA zoom control unit 122 determines whether or not the FA zoom operation switch has been released from the long press state. When the FA zoom operation switch is opened (third operation), the end of the FA zoom is determined. That is, the FA zoom control unit 122 continues the framing support zoom while the operation unit 117 is pressed (operated) in the manual search mode. When the pressing of the operation unit 117 ends, the process proceeds to step S124. In step S124, the FA zoom control unit 122 instructs the CZ control unit 119 or the electronic zoom control unit 120 to drive to the stored optical zoom position and electronic zoom position (zoom-in position), and FIG. The FA zoom-in operation described later is performed. Thereby, the FA zoom function in the manual search mode ends.

  On the other hand, if the automatic tracking mode is selected, the automatic tracking mode is stored in the memory 118 in step S106, and then subject designation processing is performed in step S107.

  Here, the subject designation processing in step S107 will be described with reference to FIG. FIG. 9A shows a flowchart of an operation example in which a subject displayed on the display unit 109 is touched and specified using a touch panel which is a member constituting the operation unit 117. In step S200, the FA zoom control unit 122 determines whether the touch panel has been pressed. When the touch panel is pressed, the process proceeds to step S201, and the FA zoom control unit 122 acquires information on a touched position (touch position).

  Subsequently, in step S202, the FA zoom control unit 122 notifies the subject detection unit 123 of the touch position, and the subject detection unit 123 performs face detection near the touch position. If a face is detected near the touch position, it is determined that the main subject is a person, and the process proceeds to step S203. In step S <b> 203, the FA zoom control unit 122 stores the face information of the person who is the target of automatic tracking in the memory 118. Specific face information includes the face size, face detection position, face orientation, etc. when the subject is designated. Further, in a camera having a face authentication function, an authentication ID is also stored.

  On the other hand, if no face is detected in the vicinity of the touch position in step S202, it is determined that the main subject is an object other than a person, and the process proceeds to step S204. In step S <b> 204, the FA zoom control unit 122 stores the characteristic color near the touch position in the memory 118 as automatic tracking target color information. Specific color information includes the color and brightness of the characteristic color when the subject is designated, the value of the color difference, the size of the same color area, the center of gravity position of the same color area, and the like. The face information and color information are collectively referred to as subject information (subject size, subject detection position, etc.) in the following description.

  When the subject information is stored in step S203 or S204, the process proceeds to step S205. In step S205, the FA zoom control unit 122 displays on the display unit 109 a subject tracking frame (mono tracking frame 400 or face tracking frame 500) having a size corresponding to the subject size with the subject detection position as the center. Thus, the subject designation process ends.

  As described above, when the mode is the automatic tracking mode, the system control unit 114 (subject detection unit 123) detects the subject at the position designated by the photographer on the display unit 109 or in the vicinity of the designated position. Then, the system control unit 114 (FA zoom control unit 122) displays the subject tracking frame on the display unit 109. According to the flowchart of FIG. 9A, it is possible for the photographer to easily specify the subject to be tracked by an intuitive designation method.

  FIG. 9B shows a flowchart of an operation example in which the subject is designated by a switch (subject designation switch) different from the FA zoom operation switch which is a member constituting the operation unit 117. First, in step S <b> 206, the FA zoom control unit 122 displays a frame that serves as a standard for subject specification near the center of the screen of the display unit 109. The photographer adjusts the direction of the camera so that the subject to be tracked is located near the center using this frame as a guide. Subsequently, in step S207, the FA zoom control unit 122 determines whether or not the subject specifying switch has been pressed. If the subject designation switch is pressed, the process proceeds to step S208.

  In step S208, the subject detection unit 123 performs face detection near the center of the screen. If a face is detected near the center of the screen, it is determined that the main subject is a person, and the process proceeds to step S209. On the other hand, if no face is detected near the center of the screen, it is determined that the main subject is something other than a person, and the process proceeds to step S210. When the subject information is stored in step S209 or S210, the process proceeds to step S211. In step S211, the subject tracking frame (the mono tracking frame 400 or the face tracking frame 500) is displayed, and the subject designation process ends. The basic processes in steps S209, S210, and S211 in FIG. 9B are the same as steps S203, S204, and S205 in FIG. 9A, respectively.

  As described above, when the mode is the automatic tracking mode, the system control unit 114 (subject detection unit 123) detects the subject at the screen center position of the display unit 109 or in the vicinity of the screen center position. The system control unit 114 (FA zoom control unit 122) displays a subject tracking frame indicating the position of the subject on the display unit 109. According to the flowchart in FIG. 9B, it is possible to easily specify a subject even in a camera not equipped with an operation member such as a touch panel.

  FIG. 9C shows a flowchart of an example in which the subject to be tracked is automatically selected from the faces detected when the FA zoom operation switch which is a member constituting the operation unit 117 is short-pressed. . First, in step S212, the subject detection unit 123 performs face detection on the entire screen. If even one person is detected on the entire screen, it is determined that the main subject is a person, and the process proceeds to step S213. In step S213, the subject detection unit 123 sets the face as the main face when the detected face is one person. When there are a plurality of detected faces, the subject detection unit 123 selects a main face as a subject to be tracked from the faces. As a determination criterion for main face selection, for example, there is a method of selecting a face whose face detection position is located near the center of the screen. In addition, when there are a plurality of faces at the same position, there is a method of selecting a larger face as the main face. In addition, in a camera having a face authentication function, when there is a face registered for authentication, there is a method in which the face is given priority as a main face. In step S213, the FA zoom control unit 122 stores the face information of the selected main face in the memory 118. When the face information is stored in step S214, the process proceeds to step S215, and the FA zoom control unit 122 displays the face tracking frame 500.

  Subsequently, in step S216, if the main face automatically selected when a plurality of faces is detected is a face not intended by the photographer, the photographer can change the main face. At this time, when a switch on the operation unit 117 (which may be an FA zoom operation switch or another switch) is pressed, the main face is changed to a face that has not been selected as the main face from the detected face tracking frame 500. . If the main face has been changed, the process proceeds to step S214 again, and the FA zoom control unit 122 updates the stored face information. In step S215, the face tracking frame 500 is changed to the size and detection position of the newly selected main face.

  On the other hand, if no face is detected on the entire screen in step S212, it is determined that the main subject is something other than a person, and the process proceeds to step S217. In step S217, the FA zoom control unit 122 stores the characteristic color near the center of the screen in the memory 118 as the color information for the automatic tracking target. When the mono information is stored in step S217, the process proceeds to step S218, and the mono tracking frame 400 is displayed. Thus, the subject designation process ends. The basic processes in steps S214, S217, and S215 (S218) in FIG. 9C are the same as steps S203, S204, and S205 in FIG. 9A, respectively.

  Thus, the system control unit 114 (subject detection unit 123) performs face detection on the entire screen of the display unit 109 when the mode is the automatic tracking mode. When a plurality of faces are detected, the system control unit 114 (FA zoom control unit 122) displays a subject tracking frame indicating the position of the first face as a subject on the display unit 109 from among the plurality of faces. In addition, when the first face is changed to the second face as the subject, the system control unit 114 (FA zoom control unit 122) displays a subject tracking frame indicating the position of the second face on the display unit 109. According to the flowchart of FIG. 9C, the subject can be easily specified with a smaller number of operations.

  When the subject designation process shown in FIG. 9 is completed, the process proceeds to step S108 in FIG. In the processing from step S108, the FA zoom control unit 122 determines whether or not to start the FA zoom operation based on the reference subject information at the time of subject designation and the subject information periodically detected. This determination is repeated at a predetermined control cycle until the condition for starting FA zoom is satisfied.

  In step S108, the subject detection unit 123 displays a subject having the same characteristics as the reference subject information from the entire screen, that is, the face is the same when the reference subject is a person, and the same characteristic color when the subject is a thing. It is determined whether or not it is detected. If the subject to be tracked is not detected, the process proceeds to step S111. On the other hand, when the subject to be tracked is detected, the process proceeds to step S109.

  The determinations in steps S109, S113, and S114 are FA zoom start determinations (for frame-out prevention control) for preventing the subject from being out of frame. In step S109, the FA zoom control unit 122 determines whether the subject tracking frame of the subject to be tracked has entered the zoom-out area ZO. If the tracking frame enters the zoom-out area ZO in step S109, that is, if there is a high possibility that the subject is out of the frame, the process proceeds to step S110, and the FA zoom-out operation is started. The FA zoom-out operation here corresponds to the zoom-out operation of the frame-out prevention control.

  On the other hand, if the subject tracking frame has not entered the zoom-out area ZO in step S109, that is, if the subject is captured near the center of the screen, the process proceeds to step S113. In step S113, it is determined whether or not the previous zoom operation is a zoom-out operation caused by entering the zoom-out area ZO in step S109, that is, a zoom-out operation for frame-out prevention control. If it is after the zoom-out operation of the frame-out prevention control, the process proceeds to step S114.

  In step S114, it is determined whether or not the subject tracking frame of the subject to be tracked is contained (included) in the zoom-in area ZI. The zoom-in area ZI here corresponds to the zoom-in area ZI described with reference to FIGS. 4B and 5A to 5C. If the tracking frame (subject) does not fit in the zoom-in area ZI in step S114, the process proceeds to step S111. On the other hand, if the tracking frame is within the zoom-in area ZI, that is, if the subject is captured so that the subject size is near the center of the screen and within the angle of view at the zoom return position, the process proceeds to step S115 and FA zoom-in is performed. Start operation. The FA zoom-in operation here corresponds to the zoom-out operation of the frame-out prevention control.

  The object of the present embodiment is to achieve both frame-out prevention control (first mode) and size retention control (second mode) in the automatic tracking mode. In view of this, first, the size holding control can be executed after the subject is caught near the center of the screen by the frame-out prevention control. For this reason, in the state after the zoom-out operation of the frame-out prevention control, the FA zoom process (steps S116 to S120) for maintaining a constant subject size (size holding control) described below is not performed. In other words, when the frame-out prevention control is performed, the size holding control is limited until the zoom-in operation of the frame-out prevention control is completed.

  If it is determined in step S113 that it is not after the zoom-out operation of the frame-out prevention control, the process proceeds to step S116. In step S116, the FA zoom control unit 122 compares the subject size of the reference subject information with the subject size detected in step S108. If the size of the subject detected in step S108 is larger than the reference subject size by a predetermined N1 (N1> 1), that is, if the ratio of the subject to the screen exceeds a predetermined value, the process proceeds to step S117. The FA zoom out operation is started. The FA zoom-out operation here corresponds to the zoom-out operation of size retention control.

  On the other hand, if it is determined in step S116 that the size of the subject detected in step S108 is not more than N1 times the size of the reference subject, the process proceeds to step S118. In step S118, the FA zoom control unit 122 compares the subject size of the reference subject information with the subject size detected in step S108. If the size of the detected subject is less than a predetermined N2 times the size of the reference subject (N2 <1), that is, if the ratio of the subject to the screen is less than the predetermined value, the process proceeds to step S119. On the other hand, when the detected size of the subject is N2 times or more than the size of the reference subject, the process proceeds to step S111.

  In step S119, the FA zoom control unit 122 determines whether or not the subject tracking frame of the subject to be tracked is within (included in) the zoom-in area ZI. This is to prevent the subject from being out of frame by the zoom-in operation when the subject is in the periphery of the screen. The zoom-in area ZI here corresponds to the zoom-in area ZI described with reference to FIG. If it is determined in step S119 that the subject tracking frame does not fit in the zoom-in area ZI, the process proceeds to step S111. On the other hand, if it is determined that the subject tracking frame is within the zoom-in area ZI, the process proceeds to step S120. In step S120, the FA zoom control unit 122 starts an FA zoom-in operation. The FA zoom-in operation here corresponds to a zoom-in operation of size retention control. As described above, in this embodiment, in order to prevent the subject from being out of the frame even in the zoom-in operation of the size holding control, the zoom-in operation is started after the subject is within the zoom-in area ZI.

  In step S111, the FA zoom control unit 122 determines whether the FA zoom operation switch of the operation unit 117 has been pressed. If the FA zoom operation switch has not been pressed, the process proceeds to step S108 again, and the FA zoom start determination is continued.

  On the other hand, when the FA zoom operation switch is pressed, the process proceeds to step S112, and the FA zoom control unit 122 measures the pressing time of the FA zoom operation switch. Even if the automatic tracking mode is being executed, if it is determined that the FA zoom operation switch is pressed for a long time, the mode is changed to the manual search mode, and the process proceeds to S121 in FIG. 8 to start FA zoom in the manual search mode. As a result, even when the FA zoom control unit 122 cannot detect the subject, when the photographer recognizes that the subject is out of frame, the zoom-out operation is instructed immediately in the manual search mode to prevent out-of-frame. it can. When it is determined in step S112 that the FA zoom operation switch is pressed shortly, the FA zoom function in the automatic tracking mode ends.

  Next, the FA zoom operation will be described with reference to FIG. FIG. 10A is a flowchart of the FA zoom-out operation performed in steps S110 and S117 in FIG. 7 and step S122 in FIG. First, in S300, the FA zoom control unit 122 acquires the optical zoom position from the CZ control unit 119 and acquires the electronic zoom position from the electronic zoom control unit 120. Further, the FA zoom control unit 122 stores the data of the optical zoom position and the electronic zoom position in the memory 118. The optical zoom position represents the position of the zoom lens corresponding to the zoom magnification that can be changed by the optical zoom function. The electronic zoom position represents a control position corresponding to the magnification of image enlargement and reduction that can be changed by the electronic zoom function. In the manual search mode, the zoom position stored here is set as the zoom return position (third zoom position).

  Subsequently, in S301, the FA zoom control unit 122 acquires a zoom-out drive amount. When the FA zoom function mode is the manual search mode (step S122 in FIG. 8), the zoom-out drive amount is a predetermined drive amount stored in the memory 118. The driving amount may be changed by the photographer by an operation from the setting menu. When the FA zoom function mode is the automatic tracking mode (steps S110 and S117 in FIG. 7), the zoom-out drive amount is set according to the detected subject information. Specifically, in the zoom-out operation for preventing frame-out (step S110 in FIG. 7), the smaller the subject size, the smaller the zoom-out drive amount is set. Thereby, it is possible to prevent the subject from becoming undetectable because the size of the subject becomes too small due to the zoom-out operation. In consideration of the minimum size that can be detected by the subject, zoom-out may not be performed when the size of the subject is smaller than a predetermined size. In the zoom-out operation for maintaining the size (step S117 in FIG. 7), the zoom-out drive amount (1 / N1 times) corresponding to the predetermined N1 times used for the determination in step S116 is set. Thereby, even when the subject cannot be detected, a minimum zoom-out operation until the size of the subject reaches the size of the reference subject can be performed. However, in order to maintain a constant size when the subject keeps moving closer to the camera during the zoom-out operation, it is necessary to operate the zoom more than the zoom-out drive amount equivalent to the predetermined magnification. This will be described later with reference to FIG.

  In step S302, the FA zoom control unit 122 determines whether the zoom state is an electronic zoom state. In a general zoom operation, when the zoom operation switch of the operation unit 117 is pressed, if the optical zoom position is between the wide end and the tele end, the CZ control unit 119 drives the optical zoom. When the optical zoom position is at the telephoto end and an operation instruction is further given in the telephoto direction, the electronic zoom control unit 120 drives the electronic zoom to enable super telephoto shooting. In order to ensure consistency between the zoom operation by the operation of the zoom operation switch and the FA zoom operation, even in the FA zoom operation, when the zoom state is the electronic zoom state, the electronic zoom is driven first. That is, it is determined whether or not the zoom position stored in the memory 118 is within the zoom area in the zoom state to be prioritized. In this embodiment, since electronic zoom is prioritized, in S302, it is determined whether or not the zoom position is in the electronic zoom area. If the zoom state at the start of FA zoom is the electronic zoom state, the process proceeds to step S303.

  In step S303, the FA zoom control unit 122 calculates the zoom-out position of the electronic zoom based on the electronic zoom position acquired in step S300 and the zoom-out drive amount acquired in step S301, and the electronic zoom control unit. Set to 120. The FA zoom control unit 122 instructs the electronic zoom control unit 120 to perform the scaling process up to the set zoom-out position of the electronic zoom. Then, the electronic zoom control unit 120 starts a zoom-out operation using the electronic zoom, and proceeds to step S304.

  In step S304, the FA zoom control unit 122 stops the electronic zoom control unit 120 according to the zoom stop determination conditions described later with reference to FIG. 11 such as the set mode, the control state in the automatic tracking mode, and the subject detection state. Let If it is determined in step S302 that the zoom position is in the optical zoom region, or if the zoom-out operation of the electronic zoom is stopped in step S304, the process proceeds to step S305.

  In step S305, the FA zoom control unit 122 determines whether it is necessary to further zoom out by optical zoom. That is, if the electronic zoom alone is not sufficient for the zoom drive of the set zoom-out drive amount, it is necessary to supplement the remaining zoom-out drive amount with the optical zoom. If it is determined that zoom-out by optical zoom is necessary, the process proceeds to step S306. In step S306, the FA zoom control unit 122 calculates the zoom-out position of the optical zoom based on the optical zoom position and the zoom-out drive amount, and sets the calculated zoom-out position in the CZ control unit 119. The FA zoom control unit 122 instructs the CZ control unit 119 to perform zoom driving to the set zoom-out position of the optical zoom. Then, the CZ control unit 119 controls the zoom lens driving unit 113, starts a zoom-out operation of optical zoom, and proceeds to step S307.

  In step S307, the FA zoom-out control unit 122 stops the CZ control unit 119 in accordance with a zoom stop determination condition described later with reference to FIG. If it is determined in step S305 that zoom-out by optical zoom is unnecessary, or if the zoom-out operation of optical zoom is stopped in step S307, the zoom-out operation is terminated.

  FIG. 10B is a flowchart of the FA zoom-in operation performed in steps S115 and S120 in FIG. 7 and step S124 in FIG. First, in step S308, the FA zoom control unit 122 acquires a zoom-in drive amount. When the mode is the manual tracking mode (step S124 in FIG. 8) or the zoom-out operation for preventing frame-out in the automatic tracking mode (step S115 in FIG. 7), the zoom-in drive amount is set to step S300 in FIG. Thus, the driving amount for zooming in to the zoom return position stored in the memory 118 is set. In the case of the zoom-in operation (step S120 in FIG. 7) of the size keeping control in the automatic tracking mode, the zoom-in driving amount (1 / N2 times) corresponding to the predetermined N2 times used for the determination in step S118 is set.

  Subsequently, in step S309, the FA zoom control unit 122 determines whether or not the zoom state is an optical zoom state. If the zoom state is the optical zoom state, the process proceeds to step S310 in order to zoom in with priority on the optical zoom. On the other hand, if the zoom state is the electronic zoom state, the process proceeds to step S312 in order to perform zoom-in with only the electronic zoom.

  In step S <b> 310, the FA zoom control unit 122 calculates the zoom-in position of the optical zoom based on the optical zoom position and the zoom-in driving amount acquired in step S <b> 308, and sets it in the CZ control unit 119. In step S310, the FA zoom control unit 122 instructs the CZ control unit 119 to drive the zoom to the zoomed-in position of the set optical zoom. Then, the CZ control unit 119 controls the zoom lens driving unit 113 to start the optical zoom-in operation, and proceeds to step S311. In step S311, the CZ control unit 119 is stopped according to a zoom stop determination condition described later with reference to FIG.

  If it is determined in step S309 that the zoom position is within the electronic zoom area, or if the optical zoom-in operation is stopped in step S311, the process proceeds to step S312. In step S312, the FA zoom control unit 122 determines whether it is necessary to further zoom in by electronic zoom. If zooming in by electronic zoom is necessary, the process proceeds to step S313. On the other hand, when zoom-in by electronic zoom is not necessary, the zoom-in operation is terminated.

  In step S313, the FA zoom control unit 122 calculates the zoom-in position of the electronic zoom based on the zoom-in driving amount acquired in step S308, and sets it in the electronic zoom control unit 120. The FA zoom control unit 122 instructs the electronic zoom control unit 120 to perform the scaling process up to the set zoom-in position of the electronic zoom. Then, the electronic zoom control unit 120 starts a zoom-in operation using the electronic zoom, and proceeds to step S314. In step S314, the electronic zoom control unit 120 is stopped according to the zoom stop determination condition described later with reference to FIG. If it is determined in step S312 that zoom-in by electronic zoom is unnecessary, or if zoom-in operation of electronic zoom is stopped in step S314, the zoom-in operation is terminated.

  Next, with reference to FIG. 11, the zoom stop process performed in steps S304 and S307 in FIG. 10A and steps S311 and S314 in FIG. 10B will be described. First, in step S400, when the zoom in operation is an optical zoom (step S307 in FIG. 10A and step S311 in FIG. 10B), the FA zoom control unit 122 performs optical zoom from the CZ control unit 119. Get the position. On the other hand, when the zoom in operation is the electronic zoom (step S304 in FIG. 10A and step S314 in FIG. 10B), the electronic zoom position is acquired from the electronic zoom control unit 120. If the acquired zoom position has reached the optical zoom wide end (in the case of zoom-out operation) or the electronic zoom tele end (in the case of zoom-in operation), the process proceeds to step S407 and the zoom is stopped. If the acquired zoom position has not reached the zoom end, the process proceeds to step S401.

  In step S401, the FA zoom control unit 122 acquires the mode information stored in the memory 118 in step S106 of FIG. 7 or step S121 of FIG. 8, and the current mode is the manual search mode or the automatic tracking mode. Judgment is made. If the current mode is the manual search mode (steps S122 and S124 in FIG. 8), the process proceeds to step S405. On the other hand, when the current mode is the automatic tracking mode (steps S110, S115, S117, and S120 in FIG. 7), the process proceeds to step S402.

  Next, in step S402, the FA zoom control unit 122 determines which zoom operation is being performed in the automatic tracking mode. When the zoom in operation is the zoom-out operation of the frame-out prevention control (step S110 in FIG. 7), the process proceeds to step S405. Otherwise, the process proceeds to step S403.

  In step S <b> 403, the FA zoom control unit 122 determines whether the subject is detected by the subject detection unit 123. When the subject is detected, the process proceeds to step S404, and when the subject is not detected, the process proceeds to step S405.

  In step S404, the size of the subject in the reference subject information is compared with the size of the subject detected in step S403. As a result of the comparison, if the difference between the size of the subject detected in step S403 and the size of the reference subject does not fall within a predetermined range (within a predetermined change amount), the process proceeds to step S400 again to stop zooming. Continue the determination. If the difference is within a predetermined range due to the zoom operation, the process proceeds to step S406, and the remaining zoom drive amount is cleared (not set). This is because the remaining zoom drive amount is cleared even when the zoom drive amount acquired in step S301 in FIG. 10A or step S308 in FIG. This is because the determination in step S305 or step S312 in FIG. 10B is advanced to no and the zoom operation is terminated. When the remaining zoom drive amount clearing process is completed in step S406, the process proceeds to step S407 to stop the zoom currently being operated.

  As a result of the determination in steps S401 to S403, when the current mode of the FA zoom function is the manual search mode, when the zoom-out operation of the frame-out prevention control in the automatic tracking mode is being performed, or during the zoom operation of the size holding control If no subject is detected, the process proceeds to step S405.

  In step S405, the FA zoom control unit 122 performs a predetermined amount of zoom driving based on the zoom driving amount acquired in step S301 of FIG. 10A or step S308 of FIG. 10B. Determine whether the amount has been driven. When the predetermined zoom drive amount is not driven, the process proceeds to step S400 again, and the zoom stop determination is continued. If the predetermined zoom drive amount is driven, the process proceeds to step S407, and the zoom in operation is stopped.

  As described above, in this embodiment, the start and stop of the zoom operation are determined based on the FA zoom function mode, the control state in the automatic tracking mode, the subject detection state, and the like. As a result, it is possible to achieve both the subject frame-out prevention control and the subject size maintenance control, and to easily adjust the angle of view of the photographer.

(Other embodiments)
The object of the present invention can also be achieved as follows. That is, a storage medium in which a program code of software in which a procedure for realizing the functions of the above-described embodiments is described is recorded is supplied to the system or apparatus. A computer (or CPU, MPU, etc.) of the system or apparatus reads out and executes the program code stored in the storage medium. In this case, the program code itself read from the storage medium realizes the novel function of the present invention, and the storage medium and program storing the program code constitute the present invention.

  Examples of the storage medium for supplying the program code include a flexible disk, a hard disk, an optical disk, and a magneto-optical disk. Further, a CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD-R, magnetic tape, nonvolatile memory card, ROM, or the like can also be used.

  Further, by making the program code read by the computer executable, the functions of the above-described embodiments are realized. Furthermore, when the OS (operating system) running on the computer performs part or all of the actual processing based on the instruction of the program code, the functions of the above-described embodiments are realized by the processing. Is also included.

  Furthermore, the following cases are also included. First, the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer. Thereafter, based on the instruction of the program code, the CPU or the like provided in the function expansion board or function expansion unit performs part or all of the actual processing.

  Further, the present invention is not limited to a device mainly intended for shooting such as a digital camera, and includes an imaging device such as a mobile phone, a personal computer (laptop type, desktop type, tablet type, etc.), a game machine, or the like. Applicable to any device to be connected. Therefore, the “imaging device” in this specification is intended to include any electronic device having an imaging function.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary. The scene to be applied may be performed not only during angle adjustment for still image shooting but also during angle adjustment during moving image recording.

DESCRIPTION OF SYMBOLS 100 Digital camera 102 Zoom lens 109 Display part 113 Zoom lens drive part 117 Operation part 118 Memory 119 CZ control part 120 Electronic zoom control part 122 FA zoom control part 123 Subject detection part

Claims (26)

An operation unit for a user to instruct a zoom operation;
Subject detection means for detecting a subject from an image;
Control means for controlling the zoom operation according to the operation of the operation unit,
The control means can execute a first mode for controlling the zoom operation based on the position of the subject, and a second mode for controlling the zoom operation based on the size of the subject. The imaging apparatus is characterized in that execution of the second mode is restricted from when the zoom operation to the wide angle side is performed in the first mode until the zoom operation to the telephoto side is completed. The control means includes
When zooming to the wide angle side in the first mode,
The imaging apparatus according to claim 1, wherein the zoom-out operation is performed by a zoom-out drive amount that is changed based on the size of the subject detected by the subject detection unit. An operation unit for a user to instruct a zoom operation;
Subject detection means for detecting a subject from an image;
Control means for controlling the zoom operation according to the operation of the operation unit,
The control means can execute a first mode in which a zoom operation is controlled based on the position of the subject, and a second mode in which the zoom operation is controlled based on the size of the subject,
The control unit changes a zoom operation start / stop condition based on at least one of a subject detection state and a zoom operation control state by the subject detection unit, and zooms to a wide angle side in the first mode. When performing an action,
An image pickup apparatus that performs a zoom-out operation by a zoom-out drive amount that is changed based on the size of the subject detected by the subject detection unit.   The zoom-out drive amount is smaller in the case of the second size smaller than the first size than in the case where the size of the subject detected by the subject detection means is the first size. The imaging apparatus according to claim 2 or 3, wherein   In the second mode, when the size of the subject detected by the subject detection unit changes beyond a predetermined change amount with respect to the reference size, the control unit approaches the size of the subject. The imaging apparatus according to claim 1, wherein the image pickup apparatus is controlled to move the zoom position in a direction.   6. The imaging apparatus according to claim 5, wherein, in the second mode, the control unit changes a start condition of a zoom operation according to a direction of the subject detected by the subject detection unit. An operation unit for a user to instruct a zoom operation;
Subject detection means for detecting a subject from an image;
Control means for controlling the zoom operation according to the operation of the operation unit,
The control means can execute a first mode in which a zoom operation is controlled based on the position of the subject, and a second mode in which the zoom operation is controlled based on the size of the subject,
The control means is in the second mode,
When the size of the subject detected by the subject detection unit changes beyond a predetermined change amount with respect to a reference size, control is performed so that the zoom position is moved in a direction in which the size of the subject approaches the reference size, An image pickup apparatus characterized in that a zoom operation start condition is changed in accordance with the direction of the subject detected by the subject detection means.   When the subject is not detected by the subject detection means during the zoom operation in the second mode, the control means controls to stop the zoom operation after performing a zoom operation for a predetermined amount. The image pickup apparatus according to claim 5, wherein the image pickup apparatus is an image pickup apparatus. An operation unit for a user to instruct a zoom operation;
Subject detection means for detecting a subject from an image;
Control means for controlling the zoom operation according to the operation of the operation unit,
The control means can execute a first mode in which a zoom operation is controlled based on the position of the subject, and a second mode in which the zoom operation is controlled based on the size of the subject,
The control means in the second mode,
When the size of the subject detected by the subject detection unit changes beyond a predetermined change amount with respect to a reference size, control is performed so that the zoom position is moved in a direction in which the size of the subject approaches the reference size, When performing a zoom operation in the second mode, if no subject is detected by the subject detection means, control is performed to stop the zoom operation after performing a zoom operation for a predetermined amount. An imaging device.   In the second mode, when the size of the subject detected by the subject detection unit changes slightly beyond a predetermined change amount with respect to the reference size, the control unit further includes the subject in the image. 10. The image pickup apparatus according to claim 5, wherein the zoom position is controlled to move to the telephoto side when included in the region 3.   11. In the second mode, the size of the subject detected by the subject detection unit is changed by a predetermined magnification according to the direction of the subject detected by the subject detection unit. The imaging device according to any one of the above.   In the second mode, when the direction of the subject detected by the subject detection unit is larger than a predetermined angle, the size of the subject detected by the subject detection unit is the predetermined change amount with respect to the reference size. The imaging apparatus according to any one of claims 5 to 11, wherein control is not performed so as to move the zoom position even if the zoom position is changed beyond.   When performing the zoom operation in the second mode, if the size of the subject detected by the subject detection means falls within the predetermined change amount with respect to the reference size, the control means The imaging apparatus according to claim 5, wherein the imaging apparatus is controlled to stop the operation.   14. The control unit according to claim 1, wherein the control unit executes the first mode when the subject detected by the subject detection unit is included outside the first region set in the image. The imaging device according to any one of the above.   In the first mode, the control means moves the zoom position to the first zoom position on the wide angle side when the subject detected by the subject detection means is included outside the first region in the image. At the same time, the zoom position before the zoom movement is set to the second zoom position, and the subject detected by the subject detection means is included in the second region in the image at the first zoom position. In this case, the image pickup apparatus according to claim 1, wherein the zoom position is controlled to move to the second zoom position.   The imaging apparatus according to claim 15, wherein the first area is changed according to a posture or a shooting state of the imaging apparatus.   The imaging device according to claim 15 or 16, wherein the second area is changed according to an attitude or a shooting state of the imaging device.   When the subject is not detected by the subject detection means during zooming to the telephoto side in the first mode, the control means moves the zoom position to the second zoom position. The image pickup apparatus according to claim 15, wherein control is performed so as to stop the zoom operation.   When performing the zoom operation in the first mode, if the size of the subject detected by the subject detection unit falls within a predetermined change amount with respect to a reference size, the control unit performs the zoom operation. The imaging apparatus according to claim 15, wherein the imaging apparatus is controlled to stop. When the first operation is performed via the operation unit, the control unit executes either the first mode or the second mode, and performs the first operation via the operation unit. When a second operation different from that is performed, the third mode is executed,
In the third mode, the control means moves the zoom position to the wide-angle side according to the second operation, sets the zoom position before the movement to the third zoom position, and further performs the third operation. The image pickup apparatus according to any one of claims 1 to 19, wherein when the operation is performed, the zoom position is controlled to move to the third zoom position.   The control means executes the third mode when the second operation is performed via the operation unit during the execution of the first mode or the second mode. The imaging device according to claim 20. A method for controlling an imaging apparatus having an operation unit for a user to instruct a zoom operation,
A subject detection step for detecting the subject from the image;
A control step for controlling a zoom operation according to an operation of the operation unit,
In the control step, a first mode for controlling the zoom operation based on the position of the subject and a second mode for controlling the zoom operation based on the size of the subject can be executed. A control method for an image pickup apparatus, wherein execution of the second mode is limited from when the zoom operation to the wide angle side is completed until the zoom operation to the telephoto side is completed. A method of controlling an imaging apparatus having an operation unit for a user to instruct a zoom operation, a subject detection step of detecting a subject from an image;
A control step for controlling a zoom operation according to an operation of the operation unit,
In the control step, a first mode for controlling the zoom operation based on the position of the subject and a second mode for controlling the zoom operation based on the size of the subject can be executed. Based on at least one of the object detection state and the zoom operation control state, the zoom operation start and stop conditions are changed,
When zooming to the wide angle side in the first mode,
A method for controlling an imaging apparatus, wherein a zoom-out operation is performed by a zoom-out drive amount that is changed based on the size of the subject detected in the subject detection step . A method of controlling an imaging apparatus having an operation unit for a user to instruct a zoom operation, a subject detection step of detecting a subject from an image;
A control step for controlling a zoom operation according to an operation of the operation unit,
In the control step, a first mode for controlling the zoom operation based on the position of the subject and a second mode for controlling the zoom operation based on the size of the subject can be executed, and the second mode In
When the size of the subject detected by the subject detection step changes beyond a predetermined change amount with respect to the reference size, control is performed so that the zoom position is moved in a direction in which the size of the subject approaches the reference size, A control method for an image pickup apparatus, wherein the start condition of the zoom operation is changed according to the orientation of the subject detected in the subject detection step. A method of controlling an imaging apparatus having an operation unit for a user to instruct a zoom operation, a subject detection step of detecting a subject from an image;
A control step for controlling a zoom operation according to an operation of the operation unit,
In the control step, a first mode for controlling the zoom operation based on the position of the subject and a second mode for controlling the zoom operation based on the size of the subject can be executed, and the second mode In
When the size of the subject detected by the subject detection step changes beyond a predetermined change amount with respect to the reference size, control is performed so that the zoom position is moved in a direction in which the size of the subject approaches the reference size, In addition, when the zoom operation is performed in the second mode, if a subject is not detected by the subject detection step , the zoom operation is controlled after a predetermined amount of zoom operation is performed. A method for controlling an image pickup apparatus. An image pickup apparatus control program configured to cause a computer to execute the image pickup apparatus control method according to any one of claims 22 to 25 .

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