JP2023047944A - Imaging device, imaging method, and program - Google Patents

Abstract

To properly adjust a focal position.SOLUTION: An imaging device 100 includes: an imaging element; an object information acquisition part which acquires the position information on an object existing in an imaging region AR0 of the imaging element; and a focus position control part which controls a focal position of the imaging device 100. The focus position control part aligns the focus position with the object which is located in the outside of an object region AR between a first position AX1 which becomes a first distance L1 in the distance from the imaging device 100 and a second position AX2 which becomes a second distance L2 shorter than the first distance L1 in the distance from the imaging device 100 and in the imaging region AR0. During a period in which the object is outside the object region AR and in the imaging region AR0, the focal position is kept aligned with the object, and when the object moves into the object region AR, the focal position is removed from the object.SELECTED DRAWING: Figure 2

Description

The present invention relates to an imaging device, an imaging method, and a program.

2. Description of the Related Art An autofocus imaging device that automatically sets a focal position is known. For example, Japanese Patent Application Laid-Open No. 2002-200002 describes that a predetermined position designated by a user is focused.

WO2017/141746

2. Description of the Related Art Autofocus imaging apparatuses are required to be properly focused.

In view of the above problems, an object of the present invention is to provide an imaging apparatus, an imaging method, and a program capable of appropriately adjusting the focus.

An imaging device according to an aspect of the present invention is an imaging device capable of imaging an object, comprising: an imaging element; a focal position control section for controlling a focal position of the apparatus, wherein the focal position control section controls a first position where the distance from the imaging device is the first distance, and a first position where the distance from the imaging device is the first distance; The focus position is adjusted to an object that is outside the target area between a second position that is a second distance shorter than one distance and that exists within the imaging area, and if the object is outside the target area The focus position is kept on the object while it is in the imaging area, and the focus position is removed from the object when the object moves into the target area.

An imaging method according to an aspect of the present invention is an imaging method for imaging an object, comprising the steps of acquiring position information of an object existing in an imaging region, and controlling the focal position of an imaging device, In the step of controlling the focus position, a first position at a first distance from the imaging device and a second position at a second distance shorter than the first distance from the imaging device. The focal position is adjusted to an object that is outside the target area between and within the imaging area, and during the period in which the object is outside the target area but within the imaging area, the Continue to focus on the object and remove the focus from the object when the object moves into the region of interest.

A program according to one aspect of the present invention is a program that causes a computer to execute an image capturing method for capturing an image of an object, and includes steps of acquiring position information of an object existing in an image capturing area and controlling a focal position of an image capturing device. and the step of controlling the focal position by causing the computer to execute and controlling the focus position includes: a first position at a first distance from the imaging device; and a first position at a distance from the imaging device that is shorter than the first distance. The focus position is adjusted to an object that is outside a target area between a second position that is two distances and that exists within the imaging area, and the object is outside the target area but within the imaging area. During the residency period, the focus position is kept on the object, and when the object moves into the region of interest, the focus position is removed from the object.

According to the present invention, it is possible to appropriately focus.

FIG. 1 is a schematic block diagram of an imaging device according to the first embodiment. FIG. 2 is a schematic diagram for explaining an example of the target area. FIG. 3 is a schematic diagram for explaining an example of the target area. FIG. 4 is a schematic diagram showing another example of the target area. FIG. 5 is a schematic diagram showing another example of the target area. FIG. 6 is a flowchart for explaining the processing flow for setting the focal position. FIG. 7 is a schematic diagram illustrating an example in which motion of an object is set as a predetermined condition. FIG. 8 is a flowchart for explaining the processing flow for setting the focal position in the second embodiment. FIG. 9 is a schematic diagram illustrating an example in which a plurality of objects are present in the target area. FIG. 10 is a flowchart for explaining the processing flow for setting the focal position according to the third embodiment. FIG. 11 is a schematic diagram for explaining a method of setting the focal position in the fourth embodiment. FIG. 12 is a flowchart for explaining the processing flow for setting the focal position according to the fourth embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Below, embodiments of the present invention will be described in detail based on the drawings. In addition, this invention is not limited by embodiment described below.

(First embodiment)
(Configuration of imaging device)
FIG. 1 is a schematic block diagram of an imaging device according to the first embodiment. An imaging device 100 according to the first embodiment is an imaging device that images an object within an imaging range. The imaging device 100 is an autofocus camera capable of automatically setting a focal position. The imaging device 100 may be a video camera that captures a moving image by capturing each predetermined frame, or may be a camera that captures a still image. The imaging device 100 may be used for any purpose, and may be used, for example, as a monitoring camera set at a predetermined position inside a facility or outdoors.

As shown in FIG. 1, the imaging device 100 includes an optical element 10, an imaging element 12, an image processing circuit 13, an object position measuring unit 14, an input unit 16, a display unit 18, a communication unit 20, It has a storage unit 22 and a control unit 24 .

The optical element 10 is an element of an optical system such as a lens. The number of optical elements 10 may be one or plural.

The imaging device 12 is a device that converts light incident through the optical device 10 into an image signal that is an electrical signal. The imaging element 12 is, for example, a CCD (Charge Coupled Device) sensor, a CMOS (Complementary Metal Oxide Semiconductor) sensor, or the like.

The image processing circuit 13 generates image data for each frame from the image signal generated by the imaging element 12 . The image data is, for example, data including luminance and color information of each pixel in one frame, and may be data to which a gradation is assigned to each pixel.

The object position measuring unit 14 is a sensor that measures the position of the object to be measured with respect to the imaging device 100 (relative position of the object). An object here may be any object, and may be a living thing or an inanimate object, and the same shall apply hereinafter. Also, the object here may refer to a movable object, but is not limited to that and may refer to an immovable object.

In this embodiment, the object position measuring unit 14 measures the distance from the imaging device 100 to the object as the relative position of the object. The object position measuring unit 14 may be any sensor capable of measuring the relative position of an object, and may be, for example, a TOF (Time Of Flight) sensor. When the object position measuring unit 14 is a TOF sensor, for example, a light emitting element (e.g., LED (Light Emitting Diode)) that emits light and a light receiving unit that receives light are provided. The distance to the object is measured from the time of flight of the light that has returned to the light-receiving unit.The object position measuring unit 14 measures the distance from the imaging device 100 to the object as the relative position of the object. For example, the direction in which the object exists with respect to the imaging device 100 may also be measured.In other words, the object position measurement unit 14 measures the position (coordinates) of the object in a coordinate system having the imaging device 100 as the origin, and calculates the relative position of the object. May be measured as position.

The input unit 16 is a mechanism for receiving input (operation) from the user, and may be, for example, buttons, a keyboard, a touch panel, or the like.

The display unit 18 is a display panel that displays images. The display unit 18 may be capable of displaying an image for the user to set a target area AR, which will be described later, in addition to the image captured by the imaging device 100 .

The communication unit 20 is a communication module that communicates with an external device, and may be, for example, an antenna or a Wi-Fi (registered trademark) module. The imaging device 100 communicates with an external device by wireless communication, but may be wired communication, and any communication method may be used.

The storage unit 22 is a memory that stores various types of information such as captured image data, calculation contents of the control unit 24, and programs. At least one of a storage device and an external storage device such as a HDD (Hard Disk Drive) is included. The program for the control unit 24 stored in the storage unit 22 may be stored in a recording medium readable by the imaging device 100 .

The control unit 24 is an arithmetic device and includes an arithmetic circuit such as a CPU (Central Processing Unit). The control unit 24 includes a target area acquisition unit 30 , an object information acquisition unit 32 , a focus position control unit 34 , an imaging control unit 36 and an image acquisition unit 38 . The control unit 24 reads out and executes a program (software) from the storage unit 22 to operate the target area acquisition unit 30, the object information acquisition unit 32, the focus position control unit 34, the imaging control unit 36, and the image acquisition unit 38. Realize and execute those processes. Note that the control unit 24 may execute these processes by one CPU, or may be provided with a plurality of CPUs and may execute the processes by the plurality of CPUs. Moreover, at least part of the processing of the target region acquisition unit 30, the object information acquisition unit 32, the focus position control unit 34, the imaging control unit 36, and the image acquisition unit 38 may be realized by hardware circuits.

(Target area acquisition unit)
The target area acquisition unit 30 acquires information on the target area AR set within the imaging area of the imaging device 100 . The target area AR is an area set for automatically adjusting the focal position. The information of the target area AR is information indicating the position of the target area AR, that is, the position information of the target area AR. The target area AR will be described below.

2 and 3 are schematic diagrams for explaining an example of the target area. 2 is a view of the imaging device 100 and the target area AR viewed from above in the vertical direction, and FIG. 3 is a view of the imaging device 100 and the target region AR viewed from the horizontal direction. Hereinafter, the direction Z is defined as a vertical direction, the direction X is defined as one horizontal direction orthogonal to the direction Z, and the direction Y is defined as a direction orthogonal to the direction Z and the direction X (horizontal direction). As shown in FIGS. 2 and 3, the range in which an image can be captured by the imaging device 100 is defined as an imaging area AR0. The imaging area AR0 refers to an area (space) within the angle of view of the imaging device 12, in other words, refers to a range captured as an image in real space. The target area AR is an area (space) set within the range of the imaging area AR0.

More specifically, the target area AR is an area within the imaging area AR0 and between the first position AX1 and the second position AX2. The first position AX1 is a position that is the first distance L1 from the imaging device 100, and the second position AX2 is the second distance L2 that is shorter than the first distance L1 from the imaging device 100. position. As shown in FIGS. 2 and 3, in the present embodiment, the first position AX1 is a virtual position (coordinates) including positions (coordinates) at a first distance L1 from the imaging device 100 in the imaging area AR0. It can be said that it is a positive aspect. Similarly, the second position AX2 can be said to be a virtual plane that includes positions (coordinates) within the imaging region AR0 that are the second distance L2 from the imaging device 100 . That is, the target area AR is surrounded by a virtual plane at a second distance L2 from the imaging device 100 and a virtual plane at a first distance L1 from the imaging device 100 in the imaging region AR0. It can be said that it is space. Note that the first position AX1 is not limited to a virtual plane in which all positions (coordinates) included in the first position AX1 are the first distance L1 from the imaging device 100, and at least A part of the positions (coordinates) may be a virtual plane that is the first distance L1 from the imaging device 100 . Similarly, the second position AX2 may be a virtual plane in which at least some positions (coordinates) included in the second position AX2 are the second distance L2 from the imaging device 100 .

4 and 5 are schematic diagrams showing other examples of target regions. 2 and 3, the target area AR is separated from the imaging area AR0 by the first position AX1 and the second position AX2 in the optical axis direction of the imaging device 100 (the depth direction of the image). However, the radiation direction (the direction in which the angle of view spreads) with respect to the optical axis direction of the imaging device 100 is not partitioned with respect to the imaging area AR0. In other words, the end surface of the target area AR in the widening direction of the angle of view matches the end surface of the imaging area AR0 in the widening direction of the angle of view. However, the target area AR may be separated from the imaging area AR0 also in the widening direction of the angle of view. That is, for example, as shown in FIGS. 4 and 5, the target area AR may be separated from the imaging area AR0 by the third position AX3 also in the widening direction of the angle of view. In this example, the third position AX3 is a virtual surface (here, a closed curved surface of a cylindrical side surface) including a position (coordinates) at a predetermined distance radially outward from the optical axis LX of the imaging device 100. is. In this case, the target area AR is an area (space) surrounded by the first position AX1, the second position AX2, and the third position AX3. Note that the third position AX3 is not limited to a virtual plane in which all positions (coordinates) included in the third position AX3 are the first distance L1 from the optical axis LX, and at least A part of the positions (coordinates) may be a virtual plane that is the third distance L3 from the optical axis LX. For example, the third position AX3 may be a virtual plane that spreads outward in the radial direction (horizontal direction and elevation angle direction) at a predetermined angle as it moves away from the imaging device 100 along the optical axis direction.

Note that the size and shape of the target area AR are not limited to those described above and may be arbitrary. Also, in the above description, the target area AR is an area set within the imaging area AR0, but it is not limited to this. For example, if the range in which distance measurement is possible by the object position measuring unit 14 is a ranging area (ranging space), the target area AR may be an area set within the ranging area. In this case, the imaging area AR0 in FIGS. 2 to 5 may be treated as the ranging area.

The target area acquisition unit 30 may acquire information on the target area AR by any method. For example, the position of the target area AR may be set in advance. In this case, the target area acquisition unit 30 may read the preset position information of the target area AR from the storage unit 22, or may receive the position information of the target area AR from another device via the communication unit 20. may be obtained. Further, for example, when the position of the target area AR is not set in advance, the target area acquiring unit 30 may automatically set the position of the target area AR. Further, for example, the user may set the position of the target area AR. In this case, for example, the user inputs information specifying the position of the target area AR (for example, the values of the first distance L1, the second distance L2, and the third distance L3) to the input unit 16, and the target area acquisition unit 30 may set the target area AR based on the position information of the target area AR specified by the user. Further, for example, the target area AR may be set by specifying coordinates. That is, for example, in the example of FIG. 2, coordinates P1, P2, P3, and P4, which are the vertex positions of the target area AR, may be specified, and an area surrounded by the coordinates P1 to P4 may be set as the target area AR.

(Object information acquisition unit)
The object information acquisition unit 32 acquires position information of an object existing within the imaging area AR0. The object information acquisition unit 32 controls the object position measurement unit 14 to cause the object position measurement unit 14 to measure the relative position of the object with respect to the imaging device 100 . The object information acquisition unit 32 acquires the measurement result of the relative position of the object with respect to the imaging device 100 by the object position measurement unit 14 as the position information of the object. The object information acquisition unit 32 sequentially acquires the position information of the object by acquiring the position information of the object at predetermined time intervals. The object information acquisition unit 32 can also acquire information indicating the shape of the object (for example, the 3D shape of the object) based on the positional information of the object. For example, the object information acquisition unit 32 can acquire the 3D shape of the object by accumulating a plurality of pieces of position information such as TOF image information.

(Focus position control section)
The focus position control section 34 sets the focus position of the imaging device 100 . The focal position control section 34 controls the focal position by controlling the position of the optical element 10 , that is, by moving the position of the optical element 10 .

The focal position control unit 34 adjusts the focal position to an object existing within the target area AR. In other words, the focal position control unit 34 sets the focal position to the position of the object determined to exist within the target area AR. In this embodiment, the focus position control unit 34 determines whether the object exists within the target area AR based on the position information of the object acquired by the object information acquisition unit 32 . When the position of the object acquired by the object information acquiring unit 32 overlaps with the position of the target area AR, the focus position control unit 34 determines that the object exists within the target area AR, and the object information acquiring unit Focus on the position of the object obtained by 32 . That is, for example, when the distance from the imaging device 100 to the object is the first distance L1 or less and the second distance L2 or more, the focus position control unit 34 determines that the object exists within the target area AR. Decide and focus on the object. On the other hand, the focus position control unit 34 does not adjust the focus position for an object that does not exist within the target area AR. That is, for example, when the distance from the imaging device 100 to the object is longer than the first distance L1 or shorter than the second distance L2, the focus position control unit 34 determines that the object does not exist within the target area AR. Make a decision and do not focus on that object.

The focal position control unit 34 continues to focus on the object while the object on which the focal position is adjusted exists within the target area AR. That is, the focal position control unit 34 determines whether the object continues to exist within the target area AR based on the position information of the object obtained by the object information obtaining unit 32 at predetermined time intervals, and determines whether the object continues to exist within the target area AR. During the period in which the object continues to exist within the target area AR, the object continues to be focused. On the other hand, when the focused object moves out of the target area AR, that is, when it no longer exists within the target area AR, the focus position control unit 34 removes the focus position from the object. , focus on a position other than the object.

Note that the focal position control unit 34 does not need to focus on an object existing within the target area AR from the start of operation of the imaging device 100 (timing when imaging becomes possible). . That is, the focal position control section 34 may adjust the focal position with respect to an object that has entered the target area AR after the start of operation. In other words, the focal position control unit 34 controls an object that exists within the target area AR at a certain timing but does not exist within the target area AR at a timing prior to that timing. You can adjust the focal position from the timing. In other words, when an object moves from outside the target area AR into the target area AR, the object may be recognized as an object to be focused on by the focus position control section 34 . That is, the focal position control unit 34 may focus on an object that has moved from outside the target area AR into the target area AR.

Further, the focal position control unit 34 may adjust the focal position to a preset set position when an object does not exist within the target area AR. The set position may be set arbitrarily, but is preferably set within the target area AR, such as the center position of the target area AR.

An example of setting the focal position described above will be described with reference to FIG. FIG. 2 shows an example in which the object A moves from position A0, through positions A1 and A2, to position A3, toward the imaging device 100. In FIG. The position A0 is farther from the imaging device 100 than the first distance L1 and is outside the target area AR. The positions A1 and A2 are within the target area AR because the distances to the imaging device 100 are equal to or less than the first distance L1 and equal to or more than the second distance L2. The position A3 is closer to the imaging device 100 than the second distance L2 and is outside the target area AR. In this case, the focus position control unit 34 does not focus on the object A at the timing when the object A is present at the position A0, and instead focuses on the set position, for example. Then, the focus position control unit 34 focuses on the object A at the timing when the object A is present at the position A1, that is, at the timing when the object A enters the target area AR. The focus position control unit 34 continues to focus on the object A even at the timing when the object A is present at the position A2, and at the timing when the object A moves to the position A3, that is, when the object A moves out of the target area AR. At this timing, the focal position is removed from the object A and the focal position is returned to the set position. That is, the focus position control unit 34 adjusts the focus position to the object A from the timing when the object A enters the target area AR, and during the period when the object A is moving within the target area AR, the moving object A , and the focal position is removed from the object A at the timing when the object A moves out of the target area AR.

Note that the focus position may be set by the user. In this case, for example, it may be possible to switch between an auto mode in which the focal position is automatically set and a manual mode in which the user sets the focal position. In the auto mode, the focal position is set by the focal position control section 34 as described above. On the other hand, in the manual mode, the user inputs an operation to set the focal position to the input unit 16, and the focal position control unit 34 sets the focal position according to the user's operation.

(imaging control unit)
The imaging control unit 36 controls imaging by the imaging device 100 to capture an image. The imaging control unit 36 controls, for example, the imaging element 12 and causes the imaging element 12 to acquire an image signal. For example, the imaging control unit 36 may cause the imaging element 12 to automatically acquire an image signal, or may acquire an image signal according to a user's operation.

(Image acquisition unit)
The image acquisition unit 38 acquires image data acquired by the imaging device 12 . For example, the image acquisition unit 38 controls the image processing circuit 13 to cause the image processing circuit 13 to generate image data from the image signal generated by the imaging element 12, and acquires the image data. The image acquisition unit 38 causes the storage unit 22 to store the image data.

(Focus position setting flow)
Next, a processing flow for setting the focal position described above will be described. FIG. 6 is a flowchart for explaining the processing flow for setting the focal position. As shown in FIG. 6, the control unit 24 acquires information about the target area AR using the target area acquiring unit 30 (step S10), and acquires position information of the object using the object information acquiring unit 32 (step S12). . The order in which steps S10 and S12 are performed may be arbitrary. The control unit 24 uses the focus position control unit 34 to determine whether the object is positioned within the target area AR based on the position information of the object (step S14). If the object is not located within the target area AR (step S14; No), the process returns to step S12 to continue acquiring the position information of the object. On the other hand, if the object is located within the target area AR (step S14; Yes), the focus position control unit 34 focuses on the object (step S16). After that, the acquisition of the positional information of the object is continued, and it is determined whether the object has moved outside the target area AR (step S18). If the object does not move outside the target area AR (step S18; No), that is, if the object continues to exist within the target area AR, the process returns to step S16 to continue focusing on the object. If the object has moved outside the target area AR (step S18; Yes), the focus position control unit 34 removes the focus position from the object (step S20). Thereafter, if the process is not to be ended (step S22; No), the process returns to step S12, and if the process is to be ended (step S22; Yes), this process is ended.

(effect)
As described above, the imaging device 100 according to the present embodiment includes the imaging device 12, the object information acquisition unit 32 that acquires the position information of an object existing in the imaging area AR0 of the imaging device 12, and the focal point of the imaging device 100. and a focus position control unit 34 for controlling the position. The focal position control unit 34 adjusts the focal position to an object existing within the target area AR, and continues to adjust the focal position to the object while the object exists within the target area AR. When moving out, move the focus position away from the object. The target area AR is between a first position AX1 at a first distance L1 from the imaging device 100 and a second position AX at a second distance L2 shorter than the first distance L1 from the imaging device 100. is the area of

Here, in an autofocus imaging apparatus, it is required to appropriately adjust the focal position. In contrast, the imaging apparatus 100 according to the present embodiment focuses on an object existing within the target area AR, and continues to focus on the object when the object continues to exist within the target area AR. Then, when the object goes out of the target area AR, the focus position is removed. Therefore, for example, it is possible to keep focusing on an object existing in the target area, which is an area to be noticed in monitoring or the like. In addition, when the object is farther than the first distance L1 or closer than the second distance L2, and the object is out of the region of interest, the focus position is removed from the object, and the Defocus can be suppressed. Therefore, according to this embodiment, it is possible to appropriately adjust the focal position.

The focal position control unit 34 also controls the focal position by moving the position of the optical element 10 provided in the imaging device 100 . According to this embodiment, it is possible to appropriately adjust the focal position.

(Second embodiment)
Next, a second embodiment will be described. The second embodiment differs from the first embodiment in that the focal position is adjusted to an object that exists within the target area AR and satisfies a predetermined condition. In the second embodiment, descriptions of the parts that are common to the first embodiment will be omitted.

In the second embodiment, the focal position control unit 34 adjusts the focal position to an object that exists within the target area AR and satisfies a predetermined condition. The focal position control unit 34 does not focus on an object that does not satisfy at least one of being present in the target area AR and satisfying a predetermined condition. The focal position control unit 34 continues to focus on the object while the object on which the focal position is adjusted satisfies a predetermined condition and continues to exist within the target area AR. On the other hand, the focus position control unit 34 removes the focus position from the object when at least one of the existence of the object within the target area AR and the satisfaction of the predetermined condition is no longer satisfied. That is, for example, if the object satisfies the predetermined condition but has moved out of the target area AR, or if it exists within the target area AR but no longer satisfies the predetermined condition, the focal position control unit 34 detects that the object Remove the focus position from

The focal position control unit 34 may determine whether or not the predetermined condition is satisfied by any method. You can The positional information of the object here may refer to the measurement result of the object position measuring unit 14, and the image of the object may refer to image data of the object captured by the imaging device 12. FIG.

The predetermined condition here may be any condition other than that the object exists within the target area AR. For example, the predetermined condition may be at least one of that the object is performing a predetermined motion, that the object has a predetermined shape, and that the object faces a predetermined direction. Also, any two of these may be used as the predetermined conditions, or all of them may be used as the predetermined conditions. When a plurality of predetermined conditions are set, the focus position control unit 34 determines that the predetermined conditions are satisfied when all the conditions are satisfied.

A case where motion of an object is a predetermined condition will be described. In this case, the focus position control unit 34 determines whether the object is moving in a predetermined manner based on the position information of the object that is continuously acquired in time series. The focal position control unit 34 adjusts the focal position with respect to an object existing within the target area AR and performing a predetermined motion. The focal position control unit 34 does not focus on an object that does not meet at least one of being within the target area AR and performing a predetermined movement. The focal position control unit 34 keeps the focal position on the object while the object on which the focal position is adjusted exists in the target area AR and continues a predetermined movement. On the other hand, the focus position control unit 34 removes the focus position from the object when the object no longer satisfies at least one of being present in the target area AR and performing a predetermined movement. Note that the motion of the object here refers to the mode of movement of the object, and may refer to, for example, the direction and speed of movement of the object. For example, if the predetermined motion means moving downward in the vertical direction at a speed of 10 m/h or more, the focal position control unit 34 moves downward in the vertical direction by 10 m/h or more in the target area AR. Focus on an object moving at a speed of Note that the motion of an object is not limited to indicating the moving direction and moving speed of an object, and may refer to any mode of movement. For example, motion of an object may refer to at least one of the direction and speed of movement of the object.

FIG. 7 is a schematic diagram illustrating an example in which motion of an object is set as a predetermined condition. In the example of FIG. 7, the predetermined condition is that the object moves downward in the vertical direction (direction opposite to the Z direction), that is, the moving direction of the object. In the example of FIG. 7, the object A moves downward in the vertical direction from position A0a through positions A1a and A2a to position A3a and stops at position A3a. The position A0a is outside the target area AR, and the positions A1a, A2a, and A3a are inside the target area AR. In this case, the focus position control unit 34 does not focus on the object A because the object A is outside the target area AR at the timing when the object A exists at the position A0a. . Then, the focal position control unit 34 focuses on the object A at the timing when the object A is present at the position A1a, that is, at the timing when the object A enters the target area AR while moving downward in the vertical direction. The focus position control unit 34 continues to focus on the object A even at the timing when the object A is present at the position A2a, and removes the focus position from the object A at the timing when the object A moves to the position A3a and stops. , to return the focal position to the set position.

Next, a case where the shape of an object is set as a predetermined condition will be described. In this case, the focus position control section 34 determines whether the object has a predetermined shape based on the image data showing the object. The focal position is adjusted to an object that exists within the target area AR and has a predetermined shape. The focal position control unit 34 does not focus on an object that does not satisfy at least one of being within the target area AR and having a predetermined shape. The focal position control unit 34 continues to focus on the object while the object on which the focal position is adjusted has a predetermined shape and continues to exist within the target area AR. On the other hand, the focus position control unit 34 removes the focus position from the object when the object no longer satisfies at least one of being in the target area AR and having a predetermined shape. The shape of the object here may be, for example, at least one of the size of the object and the outline of the object. For example, when the predetermined shape indicates a predetermined size or more, the focus position control unit 34 adjusts the focus position to an object of a predetermined size or more that exists within the target area AR. . Note that 3D shape information acquired by the object information acquiring unit 32 may be used to acquire the shape information of the object.

A case where the orientation of an object is a predetermined condition will be described. In this case, the focal position control unit 34 determines whether the object faces a predetermined direction based on the image data showing the object. A focal position is adjusted to an object that exists within the target area AR and faces in a predetermined direction. The focal position control unit 34 does not focus on an object that does not satisfy at least one of being in the target area AR and being oriented in a predetermined direction. The focal position control unit 34 continues to focus on the object while the object on which the focal position is adjusted continues to exist within the target area AR while facing the predetermined direction. On the other hand, when the object no longer satisfies at least one of being in the target area AR and facing a predetermined direction, the focus position control unit 34 removes the focus position from the object. . Note that 3D shape information acquired by the object information acquiring unit 32 may be used to acquire information on the orientation of the object.

Note that the predetermined condition may be set by any method, and may be set in advance, for example. In this case, the focal position control unit 34 may read out information indicating a predetermined condition (for example, moving direction and moving speed) from the storage unit 22, or may read the information indicating the predetermined condition from the storage unit 22, or may transmit the information to another device via the communication unit 20. A predetermined condition may be obtained from. Further, for example, when the predetermined condition is not set in advance, the focus position control section 34 may automatically set the predetermined condition. Alternatively, for example, the user may set a predetermined condition. In this case, for example, the user inputs information specifying a predetermined condition (for example, moving direction and moving speed) to the input unit 16, and the focal position control unit 34 controls the predetermined condition based on the information specified by the user. may be set.

Next, a focus position setting flow in the second embodiment will be described. FIG. 8 is a flowchart for explaining the processing flow for setting the focal position in the second embodiment. As shown in FIG. 8, the control unit 24 acquires information on the target area AR by the target area acquisition unit 30 (step S30), acquires a predetermined condition by the focus position control unit 34 (step S32), The object information acquisition unit 32 acquires the position information of the object and the information on the condition (step S34). Information about conditions is information for determining whether an object satisfies a predetermined condition, and refers to, for example, position information of an object, image data of an object, and the like. The order in which steps S30, S32, and S34 are performed may be arbitrary. The control unit 24 uses the focus position control unit 34 to determine whether the object satisfies a predetermined condition and is positioned within the target area AR (step S36). If the object does not satisfy at least one of the predetermined condition and the object being located within the target area AR (step S36; No), the process returns to step S12 to continue acquiring the position information of the object. On the other hand, if the object satisfies the predetermined condition and is located within the target area AR (step S36; Yes), the focus position control unit 34 focuses on the object (step S38). After that, the positional information of the object and the information about the condition are continuously acquired, and it is determined whether the object does not satisfy the predetermined condition or has moved outside the target area AR (step S40). If the object satisfies the predetermined condition and is located within the target area AR (step S40; No), that is, if the object continues to exist within the target area AR while satisfying the predetermined condition, return to step S38, Keep your focus on the object. If the object does not satisfy at least one of the predetermined condition and the object being located within the target area AR (step S40; Yes), the focus position control unit 34 removes the focus position from the object ( step S42). Thereafter, if the process is not to be ended (step S44; No), the process returns to step S34, and if the process is to be ended (step S44; Yes), this process is ended.

As described above, in the second embodiment, the focus position control unit 34 may focus on an object that is present in the target area AR and is performing a predetermined movement. The focus position control unit 34 keeps the focus position on the object while the object is moving in a predetermined manner, and removes the focus position from the object when the object stops moving in the predetermined direction. In this way, in addition to being within the target area AR, satisfying a predetermined motion is also a condition for focusing, so that an object that is moving in a specific manner can be tracked and the focus position can be adjusted appropriately. It is possible to match. For example, it is possible to detect a fall within the target area AR.

In the second embodiment, the focus position control unit 34 may focus on an object that exists in the target area AR and has a predetermined shape. In this way, in addition to being within the target area AR, the object having a predetermined shape is also a condition for adjusting the focus position, so that an object with a specific shape can be tracked and the focus position can be appropriately adjusted. It becomes possible.

In the second embodiment, the focal position control unit 34 may focus on an object that exists in the target area AR and faces in a predetermined direction. In this way, in addition to being within the target area AR, by setting the condition that the object is oriented in a predetermined direction as a condition for adjusting the focus position, an object in a specific direction is tracked and the focus position is appropriately adjusted. becomes possible.

(Third embodiment)
Next, a third embodiment will be described. The third embodiment is different from the first embodiment in that it defines how to adjust the focal position when a plurality of objects are present within the target area AR. In the third embodiment, descriptions of parts that are common to the first embodiment will be omitted. In addition, 3rd Embodiment is applicable also to 2nd Embodiment.

The object information acquisition unit 32 causes the object position measurement unit 14 to measure the relative position of each object, and acquires the position information of each object existing within the imaging area AR0. The focal position control unit 34 determines whether each object is positioned within the target area AR based on the position information of each object. When the focus position control unit 34 determines that a plurality of objects are positioned within the target area AR at the same timing, the focus position control unit 34 adjusts the focus position so that each object existing within the target area AR is in focus. switch. That is, the focus position control unit 34 keeps the focus position on one object existing within the target area AR for a predetermined time, and then switches the focus position to another object existing within the target area AR. The object is kept in focus for a predetermined time. After repeating this process until all the objects in the target area AR have been focused, the focus position control unit 34 refocuses on the first focused object and repeats this process. continue. Note that even during this process, the focus position control unit 34 continues to determine whether an object is positioned within the target area AR. Do not align.

In this embodiment, the focus position control unit 34 sets the order of switching the focus position, that is, the object to be focused next, based on the position information of each object existing within the target area AR. do. For example, the focus position control unit 34 may set the order of switching the focus positions so that the time required for switching the focus positions is minimized. That is, the amount of movement of the optical element 10 for switching the focal position corresponds to the distance (object distance) between the switching source position and the switching destination position. The shorter the object distance, the shorter the time required for switching. Therefore, the focal position control unit 34 is configured to minimize the object distance, in other words, to minimize the time required for switching the focal position based on the position information of each object existing within the target area AR. , set the order of switching the focal position.

FIG. 9 is a schematic diagram illustrating an example in which a plurality of objects are present in the target area. A setting example of the order of switching the focal positions will be described with reference to FIG. 9 . FIG. 9 exemplifies a case where the objects Aa, Ab, Ac, and Ad continue to be positioned within the target area AR. For example, among the objects Aa, Ab, Ac, and Ad, the object with the shortest distance from the current focal position (for example, the object distance from the set position) is assumed to be the object Aa. In this case, the focus position control unit 34 minimizes the time required for switching the focus position by switching the focus position to the object Aa having the shortest object distance from the current focus position. Next, among the objects Ab, Ac, and Ad that have not been focused so far, the object with the shortest object distance from the object Aa is the object Ab. Therefore, the focus position control unit 34 minimizes the time required for switching the focus position by switching the focus position from the object Aa to the object Ab, with the object Ab having the smallest object distance as the next target. Next, among the objects Ac and Ad that have not been focused on until now, the object that has the shortest object distance from the object Ab is the object Ad. Therefore, the focus position control unit 34 switches the focus position from the object Ab to the object Ad, with the object Ad having the smallest object distance as the next target. Next, since the only object that is not focused is object Ac, the focus position control unit 34 switches the focus position from object Ad to object Ac, with object Ac as the next object. After that, there is no longer any object whose focus position has not been adjusted, so the focus position is switched to the object Aa whose focus position was adjusted first, and the same processing is continued.

In this way, the focal position control unit 34 switches the focal position to the object whose object distance is the shortest among the objects that have not been focused so far. Then, when there is no longer any object whose focus position has not been adjusted, in other words, when the focus position is adjusted on all objects, among the objects currently positioned within the target area AR, Adjust the focal position for the combined object. However, the method of setting the order of switching the focal positions is not limited to the above and may be arbitrary. For example, the focal position control unit 34 may switch the focal position to an object having the maximum object distance, or may switch the focal position in order of shortest distance from the imaging device 100 .

Note that the predetermined time, which is the time during which the focus position is kept on one object, may be set arbitrarily. For example, the predetermined time may be set to the same length for all objects, or the length of the predetermined time may be different for each object. In this case, for example, the focus position control unit 34 assigns an importance level to each object based on at least one of position information of the object and image data of the object, and the higher the importance level, the longer the predetermined time. . Any method may be used for assigning the degree of importance. For example, the focus position control unit 34 may set the degree of importance of an object higher as the distance to the imaging device 100 is shorter, or an object closer to the imaging device 100 may be set. The higher the speed, the higher the importance of the object may be set.

Further, the focal position control unit 34 may stop switching the focal position to another object and continue to focus on one object while a plurality of objects are present in the target area AR. For example, when the user inputs a command to stop switching the focus position (a command to fix the focus position on the object) to the input unit 16 at the timing when the focus position is set on a certain object. , the focus position control unit 34 stops switching the focus position to another object and continues to adjust the focus position to the object.

Next, a processing flow for setting the focal position described above will be described. FIG. 10 is a flowchart for explaining the processing flow for setting the focal position according to the third embodiment. As shown in FIG. 10, the control unit 24 acquires information about the target area AR using the target area acquiring unit 30 (step S50), and acquires object position information using the object information acquiring unit 32 (step S52). . The order in which steps S50 and S52 are performed may be arbitrary. The controller 24 uses the focus position controller 34 to determine whether the object is positioned within the target area AR based on the position information of the object (step S54). If the object is not located within the target area AR (step S54; No), the process returns to step S52 to continue acquiring the position information of the object. On the other hand, if an object is located within the target area AR (step S54; Yes), the focus position control unit 34 determines whether there are multiple objects within the target area AR (step S56). If there are a plurality of objects within the target area AR (step S56; Yes), the focus position control unit 34 adjusts the focus position to the object with the smallest object distance (step S58). After that, the acquisition of the position information of the object is continued, and it is determined whether or not there is an object within the target area AR (step S60). If there is an object within the target area AR (step S60; No), the process returns to step S56 to continue setting the focal position. If there is no object within the target area AR (step S60; Yes), the focus position control unit 34 removes the focus position from the object (step S62). , and if the process is to be terminated (step S64; Yes), the process is terminated.

On the other hand, if there are not a plurality of objects within the target area AR (step S56; No), that is, if there is one object within the target area AR, the object is focused (step S66). After that, the acquisition of the position information of the object is continued, and it is determined whether or not there is an object within the target area AR (step S60). If there is an object within the target area AR (step S60; No), the process returns to step S56 to continue setting the focal position. If there is no object within the target area AR (step S60; Yes), the focus position control unit 34 removes the focus position from the object (step S62). , and if the process is to be terminated (step S64; Yes), the process is terminated.

As described above, in the third embodiment, when a plurality of objects are present in the target area AR, the focus position control unit 34 adjusts the focus positions so that the respective objects are sequentially focused. switch. Therefore, even when a plurality of objects exist within the target area AR, the focal position can be adjusted appropriately.

The focus position control unit 34 sets the order of switching the focus position according to the position of each object. Therefore, even when a plurality of objects exist within the target area AR, the focal position can be adjusted appropriately.

The focus position control unit 34 sets the order of switching the focus positions so that the time required for switching the focus positions is minimized. Therefore, even when a plurality of objects exist within the target area AR, the focal position can be adjusted appropriately.

(Fourth embodiment)
Next, a fourth embodiment will be described. The fourth embodiment is different from the first embodiment in that the focal position is not adjusted to the object existing within the target area AR, and the focal position is adjusted when the object moves outside the target area AR. In the fourth embodiment, descriptions of parts having the same configuration as in the first embodiment will be omitted. In addition, 4th Embodiment is applicable also to 2nd Embodiment and 3rd Embodiment.

The method of setting the focal position in the fourth embodiment can be explained by replacing the terms "within the target area AR" and "outside the target area AR" in the explanation of the first embodiment. A specific description will be given below.

In the fourth embodiment, the focus position control unit 34 adjusts the focus position to the object existing within the imaging area AR0 and outside the target area AR, and adjusts the focus position to the object existing within the target area AR. do not match. The focus position control unit 34 continues to focus on the object during a period in which the focused object exists within the imaging area AR0 and outside the target area AR. On the other hand, when the focused object is within the imaging area AR0 and no longer exists outside the target area AR, that is, when it moves outside the imaging area AR0 or within the target area AR, focus position control is performed. Unit 34 shifts the focus position away from the object and focuses on a position other than the object.

Furthermore, it is preferable that the focus position control unit 34 adjusts the focus position with respect to an object that has moved from within the target area AR to outside the target area AR within the imaging area AR0. This makes it possible, for example, to focus on an object that has moved from a specific area, which is preferable.

FIG. 11 is a schematic diagram for explaining a method of setting the focal position in the fourth embodiment. An example of setting the focal position described above will be described with reference to FIG. FIG. 11 shows an example in which object A moves from position A0b to position A2b through position A1b. The position A0b is within the target area AR, the position A1b is within the imaging area AR0 but outside the target area AR, and the position A2b is outside the imaging area AR0. In this case, the focal position control unit 34 does not focus on the object A at the timing when the object A exists at the position A0b, but instead sets the focal position on the set position, for example. Then, the focal position control unit 34, at the timing when the object A exists at the position A1b, that is, at the timing when the object A moves from within the target area AR to outside the target area AR within the imaging area AR0, Adjust the focal position. The focus position control unit 34 removes the focus position from the object A and returns the focus position to the set position at the timing when the object A moves to the position A2b, that is, at the timing when the object A goes out of the imaging area AR0.

Next, a processing flow for setting the focal position described above will be described. FIG. 12 is a flowchart for explaining the processing flow for setting the focal position according to the fourth embodiment. As shown in FIG. 12, the control unit 24 acquires information about the target area AR using the target area acquiring unit 30 (step S70), and acquires object position information using the object information acquiring unit 32 (step S72). . The order in which steps S70 and S72 are performed may be arbitrary. The control unit 24 uses the focal position control unit 34 to determine whether the object that was in the target area AR has moved outside the target area AR within the imaging area AR0 based on the position information of the object ( step S74). If the object has not moved outside the target area AR (step S74; No), that is, if the object continues to exist within the target area AR, the process returns to step S72 to continue acquiring the position information of the object. On the other hand, if the object moves outside the target area AR within the imaging area AR0 (step S74; Yes), the focus position control unit 34 adjusts the focus position to the object (step S76). After that, the acquisition of the position information of the object is continued, and if the object is within the imaging area AR0 and does not move from outside the target area AR (step S78; No), that is, within the imaging area AR0 but outside the target area AR If so, the process returns to step S76 and continues to focus on the object. On the other hand, if the object is within the imaging area AR0 and has moved from outside the target area AR (step S78; Yes), that is, if the object has moved outside the imaging area AR or within the target area AR, the focal position control unit 34 removes the focus position from the object (step S80). After that, if the process is not to be ended (step S82; No), the process returns to step S72, and if the process is to be ended (step S82; Yes), this process is ended.

As described above, the imaging device 100 according to the fourth embodiment includes the imaging device 12, the object information acquisition unit 32 that acquires the position information of an object existing in the imaging area AR0 of the imaging device 12, and the imaging device 100. and a focus position control unit 34 for controlling the focus position. The focal position control unit 34 focuses on an object that is outside the target area AR and that exists within the imaging area AR0. The focus position is kept on the object, and when the object moves into the target area AR, the focus position is removed from the object. The target area AR is between a first position AX1 at a first distance L1 from the imaging device 100 and a second position AX at a second distance L2 shorter than the first distance L1 from the imaging device 100. is the area of

Here, in an autofocus imaging apparatus, it is required to appropriately adjust the focal position. In contrast, the imaging apparatus 100 according to the present embodiment focuses on an object existing outside the target area AR, and continues to focus on the object when the object continues to exist outside the target area AR. . Thus, for example, objects that have left the region of interest, which is the region of interest, can remain in focus. Therefore, according to this embodiment, it is possible to appropriately adjust the focal position.

Although the embodiments of the present invention have been described above, the embodiments are not limited by the contents of these embodiments. In addition, the components described above include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those within the so-called equivalent range. Furthermore, the components described above can be combined as appropriate, and it is also possible to combine the configurations of the respective embodiments. Furthermore, various omissions, replacements, or modifications of components can be made without departing from the gist of the above-described embodiments. Further, in each embodiment, the operation of adjusting the focal position has been described as a characteristic point, but the operation of adjusting the focal position may be combined with another operation. For example, the operation of adjusting the focal position may be combined with the operation of zooming. Also, in the description of each embodiment, the operation of adjusting the focal position may be replaced with another operation. For example, in the description of each embodiment, the operation of adjusting the focal position may be replaced with the operation of zooming. Further, the control unit 24 of the imaging device in each embodiment, for example, when a set condition such as an object entering or exiting a predetermined target area AR or an object moving in a predetermined direction is satisfied, the communication unit 20 You may make it notify to a predetermined transmission destination through. The set condition here may mean, for example, that the movement of the object within the target area AR is used as a trigger to bring the object into focus.

10 optical device 12 imaging device 14 object position measurement unit 30 target area acquisition unit 32 object information acquisition unit 34 focus position control unit AR target area AR0 imaging area AX1 first position AX2 second position L1 first distance L2 second distance

Claims (5)

An imaging device capable of imaging an object,
an imaging device;
an object information acquisition unit that acquires position information of an object existing in the imaging area of the imaging device;
a focus position control unit that controls the focus position of the imaging device;
has
The focus position control unit is
Outside a target area between a first position at a first distance from the imaging device and a second position at a second distance shorter than the first distance from the imaging device, and Aligning the focus position to an object existing within the imaging area;
While the object is outside the target area but within the imaging area, the focus position is kept on the object, and when the object moves into the target area, the focus position is shifted away from the object. remove,
Imaging device. 2. The imaging apparatus according to claim 1, wherein when said object moves from inside said target region to outside said target region, said focus position control unit recognizes said object as a target on which a focus position is to be adjusted. 3. The imaging apparatus according to claim 1, wherein said focal position control section controls said focal position by moving a position of an optical element provided in said imaging apparatus. An imaging method for imaging an object,
a step of acquiring position information of an object existing in the imaging area;
and controlling the focal position of the imaging device;
In the step of controlling the focus position,
Outside a target area between a first position at a first distance from the imaging device and a second position at a second distance shorter than the first distance from the imaging device, and Aligning the focus position to an object existing within the imaging area;
While the object is outside the target area but within the imaging area, the focus position is kept on the object, and when the object moves into the target area, the focus position is shifted away from the object. remove,
Imaging method. A program for causing a computer to execute an imaging method for imaging an object,
a step of acquiring position information of an object existing in the imaging area;
causing the computer to perform a step of controlling the focus position of the imaging device;
In the step of controlling the focus position,
Outside a target area between a first position at a first distance from the imaging device and a second position at a second distance shorter than the first distance from the imaging device, and Aligning the focus position to an object existing within the imaging area;
While the object is outside the target area but within the imaging area, the focus position is kept on the object, and when the object moves into the target area, the focus position is shifted away from the object. remove,
program.

Images