Sony Patent | Imaging control apparatus, imaging control method, and program

Patent: Imaging control apparatus, imaging control method, and program

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Publication Number: 20210297594

Publication Date: 20210923

Applicant: Sony

Abstract

In subject tracking control in a case where an imaging apparatus having a hand shake correction function is used, it is possible to prevent deterioration of tracking response. Hand shake correction of an imaging apparatus is controlled on the basis of an obtained movement control amount of the imaging apparatus to make a position of a subject a predetermined position in a captured image. Therefore, the hand shake correction control is performed on the basis of a movement amount of the imaging apparatus to track the subject.

Claims

1. An imaging control apparatus comprising a control unit that controls hand shake correction of an imaging apparatus on a basis of an obtained movement control amount of the imaging apparatus to make a position of a subject a predetermined position in a captured image.

2. The imaging control apparatus according to claim 1, wherein the control unit controls the hand shake correction on a basis of a result of comparing the movement control amount with a threshold value.

3. The imaging control apparatus according to claim 2, wherein the control unit dynamically changes the threshold value.

4. The imaging control apparatus according to claim 1, wherein the control unit controls the hand shake correction on a basis of a resolution of the captured image for obtaining the movement control amount.

5. The imaging control apparatus according to claim 4, wherein the control unit controls the hand shake correction on a basis of a result of comparing the movement control amount with a threshold value, and sets the threshold value to have a negative correlation with the resolution.

6. The imaging control apparatus according to claim 3, wherein the control unit changes the threshold value depending on an imaging target scene.

7. The imaging control apparatus according to claim 1, wherein the control unit controls the hand shake correction on a basis of a movement direction of the subject.

8. The imaging control apparatus according to claim 7, wherein the control unit makes hand shake correction effects different in a direction corresponding to the movement direction and a direction different from the direction.

9. The imaging control apparatus according to claim 1, wherein the control unit obtains the movement control amount on a basis of information on the position of the subject detected from the captured image.

10. The imaging control apparatus according to claim 9, wherein the control unit obtains the movement control amount on a basis of an attention position of the subject detected from the captured image.

11. The imaging control apparatus according to claim 1, wherein the imaging apparatus that captures the captured image for obtaining the movement control amount and the imaging apparatus whose hand shake correction is controlled by the control unit are separate apparatuses.

12. The imaging control apparatus according to claim 11, wherein the control unit controls the hand shake correction on the basis of the movement control amount obtained on a basis of parallax information between the two imaging apparatuses.

13. The imaging control apparatus according to claim 1, wherein the control unit controls the hand shake correction on a basis of movement information on a head-mounted display.

14. An imaging control method comprising controlling hand shake correction of an imaging apparatus on a basis of an obtained movement control amount of the imaging apparatus to make a position of a subject a predetermined position in a captured image.

15. A program for causing an information processing device to realize a function of controlling hand shake correction of an imaging apparatus on a basis of an obtained movement control amount of the imaging apparatus to make a position of a subject a predetermined position in a captured image.

Description

TECHNICAL FIELD

[0001] The present technology relates to an imaging control apparatus, an imaging control method, and a program, and more particularly, to a control technology for hand shake correction in a case where subject tracking is performed.

BACKGROUND ART

[0002] For example, a platform apparatus capable of driving an imaging apparatus to change an imaging direction or an imaging viewpoint, such as an electric gimbal or the like, is known. Then, it is possible to perform subject tracking using this kind of the platform apparatus. Specifically, drive control of the platform apparatus (drive control of an actuator built in the platform apparatus) is performed to make a subject to be targeted positioned at a predetermined position such as a central portion or the like in a captured image.

[0003] Note that an example of a related conventional technology can include the following Patent Document 1.

CITATION LIST

Patent Document

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2015-89108

SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

[0005] Such a platform apparatus is provided with, for example, a grip portion that can be grasped by a user, such that hand-held imaging can be performed while grasping the platform apparatus by the user. In a case where the hand-held imaging is performed, a subject tracking function by rough subject tracking and drive control of the actuator described above according to a change of a direction of the platform apparatus by a user plays an auxiliary role in such a subject tracking performed by a user.

[0006] Here, in the case of the hand-held imaging, it is effective to use an imaging apparatus having a hand shake correction function as an imaging apparatus in which a platform apparatus is loaded.

[0007] However, in the imaging apparatus with the hand shake correction function, in a case where the subject tracking is performed by drive control of the platform apparatus, the hand shake correction acts in a direction opposite to a drive direction of the platform for the subject tracking, and tracking response may deteriorate. For example, in a case where a user quickly changes a direction of the platform apparatus according to a movement direction of the subject in a scene where a stationary subject starts to quickly move, the hand shake correction works (acts) in a direction opposite to the movement direction of the subject, such that the tracking response to the subject is likely to significantly deteriorate.

[0008] The present technology is made in view of the above circumstances, and an object of the present technology is to prevent the deterioration of the tracking response in the subject tracking control in a case where the imaging apparatus having the hand shake correction function is used.

Solution to Problems

[0009] According to the present technology, an imaging control apparatus includes a control unit that controls hand shake correction of an imaging apparatus on the basis of an obtained movement control amount of the imaging apparatus to make a position of a subject a predetermined position in a captured image.

[0010] With this arrangement, the hand shake correction control is performed on the basis of a movement amount of the imaging apparatus to track the subject.

[0011] In the imaging control apparatus according to the present technology, the control unit controls the hand shake correction on the basis of a result of comparing the movement control amount with a threshold value.

[0012] With this arrangement, the hand shake correction can be controlled so that the hand shake correction is maintained in a turned-on state in a case where the movement amount of the imaging apparatus is equal to or less than a predetermined amount and the hand shake correction is turned off in a case where the movement amount is larger than the predetermined amount.

[0013] In the imaging control apparatus according to the present technology, the control unit dynamically changes the threshold value.

[0014] With this arrangement, the hand shake correction effect can be adaptively changed depending on a predetermined condition.

[0015] In the imaging control apparatus according to the present technology, the control unit controls the hand shake correction on the basis of a resolution of the captured image for obtaining the movement control amount.

[0016] In a case where the movement control amount for tracking is obtained on the basis of a position of the subject detected from the captured image, a low resolution of the captured image is a noise of the movement control amount. Therefore, the hand shake correction is controlled on the basis of the resolution, such that the hand shake correction effect is prevented from being turned off unnecessarily in response to the noise.

[0017] In the imaging control apparatus according to the present technology, the control unit controls the hand shake correction on the basis of a result of comparing the movement control amount with a threshold value, and sets the threshold value to have a negative correlation with the resolution.

[0018] With this arrangement, the hand shake correction is prevented from being turned off unnecessarily in response to the noise.

[0019] In the imaging control apparatus according to the present technology, the control unit changes the threshold value depending on an imaging target scene.

[0020] With this arrangement, the hand shake correction effect can be changed depending on a change of the imaging target scene such as a scene where a subject does not move while being stationary, a scene where a stationary subject starts to quickly move, or the like.

[0021] In the imaging control apparatus according to the present technology, the control unit controls the hand shake correction on the basis of a movement direction of the subject.

[0022] With this arrangement, it is possible to reduce the hand shake correction effect for shake occurring in the movement direction of the subject and to increase the hand shake correction effect for shake occurring in a direction different from the movement direction of the subject.

[0023] In the imaging control apparatus according to the present technology, the control unit makes hand shake correction effects different in a direction corresponding to the movement direction and a direction different from the direction.

[0024] With this arrangement, it is possible to reduce the hand shake correction effect in a direction in which tracking response is more likely to deteriorate, and it is possible to increase the hand shake correction effect in a direction in which the tracking response is less likely to deteriorate.

[0025] In the imaging control apparatus according to the present technology, the control unit obtains the movement control amount on the basis of information on the position of the subject detected from the captured image.

[0026] With this arrangement, in the obtaining of the movement control amount, the position information on the subject can be detected from the captured image.

[0027] In the imaging control apparatus according to the present technology, the control unit obtains the movement control amount on the basis of an attention position of the subject detected from the captured image.

[0028] With this arrangement, tracking control can be performed by making a portion to be paid attention of the subject a predetermined position such as the central position or the like in the captured image.

[0029] In the imaging control apparatus according to the present technology, the imaging apparatus that captures the captured image for obtaining the movement control amount and the imaging apparatus whose hand shake correction is controlled by the control unit are separate apparatuses.

[0030] With this arrangement, the imaging apparatus whose hand shake correction is controlled is not required to execute processing for obtaining the movement control amount on the basis of its own captured image.

[0031] In the imaging control apparatus according to the present technology, the control unit controls the hand shake correction on the basis of the movement control amount obtained on the basis of parallax information between the two imaging apparatuses.

[0032] With this arrangement, it is possible to realize accurate subject tracking while reducing a processing load of the imaging apparatus whose hand shake correction is controlled.

[0033] In the imaging control apparatus according to the present technology, the control unit controls the hand shake correction on the basis of movement information on a head-mounted display.

[0034] With this arrangement, in a case where a movement of the head-mounted display corresponds to an instruction to switch the tracking target subject by a user, the hand shake correction acts, and thus, it is possible to prevent tracking of a new subject from being inhibited.

[0035] Furthermore, according to the present technology, an imaging control method includes controlling hand shake correction of an imaging apparatus on the basis of an obtained movement control amount of the imaging apparatus to make a position of a subject a predetermined position in a captured image.

[0036] The similar action to that of the imaging control apparatus according to the present technology described above is obtained also by such an imaging control method.

[0037] Furthermore, according to the present technology, there is provided a program for causing an information processing device to realize a function of controlling hand shake correction of an imaging apparatus on the basis of an obtained movement control amount of the imaging apparatus to make a position of a subject a predetermined position in a captured image.

[0038] The imaging control apparatus according to the present technology described above is realized by such a program.

Effects of the Invention

[0039] According to the present technology, in the subject tracking control in a case where the imaging apparatus having the hand shake correction function is used, it is possible to prevent the deterioration of the tracking response.

[0040] Note that the effects described herein are not necessarily limited and may be any effect described in the present disclosure.

BRIEF DESCRIPTION OF DRAWINGS

[0041] FIG. 1 is an explanatory view of an appearance configuration example of an imaging system including an imaging control apparatus as a first embodiment of the present technology.

[0042] FIG. 2 is a block diagram illustrating an internal configuration example of a platform apparatus of an embodiment.

[0043] FIG. 3 is a block diagram illustrating an internal configuration example of the imaging control apparatus of the first embodiment.

[0044] FIG. 4 is a flowchart illustrating a process for subject tracking.

[0045] FIG. 5 is a view schematically illustrating a state where information on a movement control amount for the subject tracking is input to the platform apparatus.

[0046] FIG. 6 is an explanatory view of an action by a hand shake correction control as the first embodiment.

[0047] FIG. 7 is a flowchart illustrating a specific processing procedure to be executed to realize the hand shake correction control as the first embodiment.

[0048] FIG. 8 is an explanatory view of an action by changing a threshold value of the movement control amount.

[0049] FIG. 9 is a flowchart illustrating a specific processing procedure to be executed to realize the hand shake correction control as Control Example I.

[0050] FIG. 10 is an explanatory view of an imaging target scene.

[0051] FIG. 11 is a flowchart illustrating a specific processing procedure to be executed to realize the hand shake correction control as Control Example II.

[0052] FIG. 12 is an explanatory view of a movement direction of a subject.

[0053] FIG. 13 is a flowchart illustrating a specific processing procedure to be executed to realize the hand shake correction control as Control Example III.

[0054] FIG. 14 is a view for explaining a configuration example of an imaging system as a first modification.

[0055] FIG. 15 is a block diagram illustrating an internal configuration example of an imaging apparatus that obtains a captured image for obtaining a movement control amount in the first modification.

[0056] FIG. 16 is a block diagram illustrating the internal configuration example of the imaging apparatus whose hand shake correction is controlled in the first modification.

[0057] FIG. 17 is an explanatory view of an example in which the imaging apparatus that obtains the captured image for obtaining the movement control amount is not mounted on the platform apparatus.

[0058] FIG. 18 is a view for explaining a configuration example of an imaging system as a second modification.

[0059] FIG. 19 is a block diagram illustrating an internal configuration example of an HMD.

[0060] FIG. 20 is a block diagram illustrating an internal configuration example of an imaging apparatus in the second modification.

[0061] FIG. 21 is a flowchart illustrating a specific processing procedure to be executed to realize an operation as the second modification.

[0062] FIG. 22 is a view illustrating a platform apparatus that can be driven in a roll direction.

MODES FOR CARRYING OUT THE INVENTION

[0063] Hereinafter, embodiments will be described in the following order. [0064] <1. First Embodiment> [0065] [1-1. Configuration Example of Apparatus] [0066] [1-2. Regarding Subject Tracking] [0067] [1-3. Hand Shake Correction Control] [0068] <2. Second Embodiment> [0069] [2-1. Control Example I] [0070] [2-2. Control Example II] [0071] [2-3. Control Example III] [0072] <3. Modification> [0073] [3-1. First Modification] [0074] [3-2. Second Modification] [0075] [3-3. Other Modifications] [0076] <4. Summary of Embodiments> [0077] <5. Present Technology>

1. First Embodiment

1-1. Configuration Example of Apparatus

[0078] FIG. 1 is an explanatory view of an appearance configuration example of an imaging system including an imaging control apparatus (imaging apparatus 10) as a first embodiment of the present technology.

[0079] The imaging system includes the imaging apparatus 10 and a platform apparatus 1. In the imaging system, an imaging direction of the imaging apparatus 10 is changed by a rotation operation of the platform apparatus 1 in a state where the imaging apparatus 10 is loaded on the platform apparatus 1. Particularly, the platform apparatus 1 includes an actuator as described later, and drive control of the actuator is performed, such that automatic tracking of a subject which is a tracking target is performed.

[0080] Note that the “imaging direction” is a direction corresponding to a direction in which the imaging apparatus 10 captures an image, and refers to a front direction (a direction indicating a subject side) in an optical axis of an imaging optical system included in the imaging apparatus 10. In the case of the system illustrated in FIG. 1, the imaging direction is changed according to a rotation angle of the platform apparatus 1, and thus, the imaging direction is uniquely determined according to the rotation angle of the platform apparatus 1.

[0081] FIG. 1A illustrates a state where the imaging apparatus 10 is loaded (mounted) on the platform apparatus 1, and FIG. 1B illustrates only the platform apparatus 1.

[0082] In the platform apparatus 1, a rotation shaft portion 2 for rotation in a Yaw direction indicated by an arrow D1 in FIG. 1B and a rotation shaft portion 3 for rotation in a Pitch direction indicated by an arrow D2 are provided, and a base portion 4, a mounting portion 5, and an arm portion 6 are also provided.

[0083] The mounting portion 5 is, for example, an L-shaped member, and a joint mechanism 5a corresponding to a mechanism (not illustrated) formed at a bottom of the imaging apparatus 10 is provided on a top surface of a bottom of the mounting portion 5. Therefore, the imaging apparatus 10 can be fixed as illustrated in FIG. 1A.

[0084] The mounting portion 5 is attached to the arm portion 6 via the rotation shaft portion 3. Therefore, the mounting portion 5 is rotatable with respect to the arm portion 6 in the Pitch direction.

[0085] The arm portion 6 is, for example, an L-shaped member, and is attached to the base portion 4 at the rotation shaft portion 2. Therefore, the arm portion 6 (and the mounting portion 5 connected to the arm portion) is rotatable in the Yaw direction.

[0086] For example, such a platform apparatus 1 is used, such that the imaging direction of the imaging apparatus 10 can be changed to the Yaw direction and the Pitch direction. Therefore, the automatic tracking of the subject can be performed.

[0087] FIG. 2 is a block diagram illustrating an internal configuration example of the platform apparatus 1.

[0088] The platform apparatus 1 includes an actuator 7, a drive control unit 8, and a communication unit 9.

[0089] As the actuator 7, a Yaw direction actuator (motor) for rotationally driving the rotation shaft portion 2 and a Pitch direction actuator (motor) for rotationally driving the rotation shaft portion 3 are provided in the present example.

[0090] The drive control unit 8 includes a drive circuit of the actuator 7, a control circuit for controlling the drive circuit, or the like, and performs drive control of the actuator 7. In particular, the drive control unit 8 of the present example performs the drive control of the actuator 7 according to information input via the communication unit 9.

[0091] The communication unit 9 performs data communication with an external apparatus according to a predetermined communication format. In particular, the communication unit 9 of the present example performs data communication according to a communication format supported by a communication unit 19 included in the imaging apparatus 10 as described later.

[0092] FIG. 3 is a block diagram illustrating an internal configuration example of the imaging apparatus 10.

[0093] The imaging apparatus 10 is a digital camera apparatus. The imaging apparatus 10 captures an image of a subject, and can record image data as a still image or a moving image in a recording medium, or transmit the image data to an external apparatus.

[0094] The imaging apparatus 10 as illustrated includes an imager (image sensor) 11, a camera signal processing unit 12, a microphone 13, an audio signal processing unit 14, an encoding unit 15, a control unit 16, a memory unit 17, a media drive 18, a communication unit 19, a bus 20, a shake correction actuator 21, a correction control unit 22, and a motion sensor 23. The camera signal processing unit 12, the audio signal processing unit 14, the encoding unit 15, the control unit 16, the memory unit 17, the media drive 18, and the communication unit 19 are connected to the bus 20, and the respective units can perform data communication with each other via the bus 20.

[0095] The imager 11 is, for example, an imaging sensor such as a charge coupled device (CCD) sensor, a complementary metal oxide semiconductor (CMOS) sensor, or the like. The imager 11 receives subject light incident through the imaging optical system (not illustrated), converts the subject light into an electric signal, and outputs the electric signal.

[0096] The imager 11 executes, for example, correlated double sampling (CDS) processing, automatic gain control (AGC) processing, and the like of the electric signal obtained by photoelectric conversion of the received light, and further performs analog/digital (A/D) conversion processing. Then, the imager 11 outputs an image signal as digital data to the camera signal processing unit 12 provided at the subsequent stage.

[0097] The camera signal processing unit 12 is, for example, an image processing processor such as a digital signal processor (DSP) or the like. The camera signal processing unit 12 performs various signal processing for a digital signal (image signal) from the imager 11. For example, the camera signal processing unit 12 performs pre-processing, synchronization processing, YC generation processing, resolution conversion processing, and the like.

[0098] After a sound collection signal from the microphone 13 is converted into a digital signal via an amplifier or an A/D converter (not illustrated), a predetermined audio signal processing is performed by the audio signal processing unit 14.

[0099] The encoding unit 15 receives the image signal and an audio signal from the camera signal processing unit 12 and the audio signal processing unit 14, respectively, and encodes the image signal and the audio signal according to a predetermined data format. As the encoding, encoding that compresses the amount of data is performed, and specifically, examples of the encoding can include compression coding such as H264, Moving Picture Experts Group (MPEG)-2, or the like for an image signal as a moving image, MPEG Audio Layer-3 (MP3), advanced audio coding, or the like for an audio signal, and the like.

[0100] The image signal or the audio signal encoded by the encoding unit 15 is hereinafter referred to as “coded data”.

[0101] The control unit 16 includes a microcomputer (information processing device) including a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and the like. The CPU executes processing in accordance with a program stored in the ROM and the like to generally control the entire imaging apparatus 10.

[0102] The RAM is a work area at the time of various data processing of the CPU, and is used to temporarily store data or programs, for example. The ROM is used to store application programs for various operations, firmware, or the like, in addition to an operating system (OS) for allowing the CPU to control each unit or content files such as image files or the like.

[0103] For example, the control unit 16 can control the coded data obtained by the encoding unit 15 to be recorded in the recording medium mounted in the media drive 18, or can control the communication unit 19 to transmit the coded data to the external apparatus.

[0104] Furthermore, in particular, the control unit 16 in the present example has a function as a tracking control processing unit F1 and a hand shake correction control processing unit F2, and these functions will be described later.

[0105] The memory unit 17 includes, for example, a non-volatile memory, and is used to store various data. In particular, the memory unit 17 is used to store data used in various processing performed by the control unit 16.

[0106] The media drive 18 is configured to be detachably attachable to a portable recording medium, and is configured as a reader/writer unit that reads and writes data to and from the mounted recording medium. Examples of the recording medium to which the media drive 18 is detachably attachable can include a memory card (for example, a portable flash memory) that can be detachably attachable to the imaging apparatus 10 and the like.

[0107] The communication unit 19 performs data communication with an external apparatus according to a predetermined communication format. In particular, the communication unit 19 of the present example can perform data communication with the communication unit 9 in the platform apparatus 1.

[0108] Here, the data communication between the communication unit 9 in the platform apparatus 1 and the communication unit 19 may be, for example, wire communication such as universal serial bus (USB) or the like, or wireless communication such as Bluetooth (registered trademark) or the like.

[0109] The shake correction actuator 21, the correction control unit 22, and the motion sensor 23 are provided to realize an optical hand shake correction function.

[0110] The motion sensor 23 is a sensor that detects a movement in a predetermined direction of the imaging apparatus 10. In the present example, an angular velocity sensor (biaxial angular velocity sensor) for detecting a movement in a rotation direction of each of the Yaw direction and the Pitch direction.

[0111] The shake correction actuator 21 is an actuator for driving a shake correction lens provided in the imaging optical system of the imaging apparatus 10.

[0112] The correction control unit 22 calculates a deviation between the imager 11 and an optical axis on the basis of movement information (angular velocities in the Yaw direction and the Pitch direction in the present example) detected by the motion sensor 23, calculates a movement amount of the shake correction lens required in a direction to cancel the deviation, and generates a drive signal for the shake correction actuator 21 according to the movement amount.

[0113] The shake correction actuator 21 is driven on the basis of the drive signal, such that the shake correction lens is displaced to cancel the deviation between the imager 11 and the optical axis, and thus, shake correction is realized.

[0114] Note that, in the optical hand shake correction, a method of displacing the imager 11 can be adopted instead of a method of displacing the shake correction lens.

1-2. Regarding Subject Tracking

[0115] In the imaging apparatus 10, the control unit 16 performs drive control of the platform apparatus 1 to make a position of a tracking target subject a target position in a captured image by specifying a position of a tracking target subject on the basis of a captured image obtained by an imaging operation of the imager 11, calculating an error amount between the specified position of the tracking target subject and a target position in the captured image, and outputting a movement control amount of the imaging apparatus 10 based on the calculated error amount to the platform apparatus 1, by a function as the tracking control processing unit F1.

[0116] FIG. 4 is a flowchart illustrating a process for subject tracking executed by the control unit 16.

[0117] Note that the process illustrated in FIG. 4 is repeatedly executed for each frame of the captured image.

[0118] First, the control unit 16 obtains a position of a subject in step S101. That is, a position of the tracking target subject in the captured image is specified. As processing in step S101, the control unit 16 performs image analysis to specify the tracking target subject on the basis of the image signal processed (or in a processing process) by the camera signal processing unit 12, and also specifies a position of the specified tracking target subject in the captured image.

[0119] In the present example, an attention position is specified as the position of the tracking target subject.

[0120] Here, the attention position refers to a determined position to be paid attention of the tracking target subject. If the subject is a person, examples of the attention position can include the center (center in vertical and horizontal directions) or the center of gravity of the whole body, the center of face, the center of shoulders, the center of torso, and the like. Alternatively, if the subject is a train or an automobile, examples of the attention position can include a leading end, a driver’s seat position, or the like in a traveling direction thereof.

[0121] In the present example, the attention position is predetermined depending on a type of the subject, and the control unit 16 specifies an attention position of the tracking target subject depending on a type of the tracking target subject.

[0122] Note that it is conceivable that the attention position is predetermined for each type of the subject according to user operations.

[0123] In following step S102, the control unit 16 obtains an error amount between a target position in an image and a position of a subject. That is, in the present example, the control unit 16 obtains an error amount between the specified position (attention position) of the tracking target subject and the target position in the captured image as described above. Here, the target position is, for example, the center (center in horizontal and vertical directions) of the captured image. Furthermore, error amounts in both the horizontal direction and the vertical direction are obtained as the error amount. Hereinafter, as for the error amount between the position of the tracking target subject and the target position in the captured image, the error amount in the horizontal direction is referred to as an “error amount .DELTA.Ph” and the error amount in the vertical direction is referred to as an “error amount .DELTA.Pv”.

[0124] In step S103 following step S102, the control unit 16 performs processing for converting (changing) the error amount of the image into an error amount of an angle. That is, the error amounts .DELTA.Ph and .DELTA.Pv obtained in step S102 and represented by a pixel number unit are converted into error amounts in the rotation directions of the Yaw direction and the Pitch direction, respectively. The conversion can be performed on the basis of an imaging parameter (a focal distance, size information on the imager 11, or the like) of the imaging apparatus 10.

[0125] Hereinafter, the error amount obtained by changing the error amount .DELTA.Ph in the horizontal direction to an angle in the Yaw direction is referred to as an “error amount .DELTA.Ay”, and the error amount obtained by changing the error amount .DELTA.Ph in the vertical direction to an angle in the Pitch direction is referred to as an “error amount .DELTA.Ap”.

[0126] In step S104 following step S103, the control unit 16 performs processing for outputting the error amounts .DELTA.Ay and .DELTA.Ap to the platform apparatus 1 as movement control amounts in the Yaw direction and the Pitch direction. That is, the control unit 16 executes processing for transmitting the error amounts .DELTA.Ay and .DELTA.Ap to the platform apparatus 1 via the communication unit 19.

[0127] Here, the movement control amount refers to a control amount of the movement when the imaging apparatus 10 is moved in a predetermined direction for the subject tracking. The error amounts .DELTA.Ay and .DELTA.Ap correspond to a control amount to move the imaging apparatus 10 in the Yaw direction and a control amount to move the imaging apparatus 10 in the Pitch direction, respectively.

[0128] By the processing described above, the movement control amounts in both the Yaw direction and the Pitch direction are input from the imaging apparatus 10 to the platform apparatus 1 as illustrated in FIG. 5.

[0129] In the platform apparatus 1, the error amounts .DELTA.Ay and .DELTA.Ap are input to the drive control unit 8 via the communication unit 9, and the drive control unit 8 drives the actuators 7 (the Yaw direction actuator and the Pitch direction actuator) with drive amounts according to these error amounts .DELTA.Ay and .DELTA.Ap.

[0130] Therefore, tracking control is realized to make the position of the tracking target subject to coincide with the target position in the captured image.

1-3. Hand Shake Correction Control

[0131] Subsequently, the hand shake correction control processing unit F2 included in the control unit 16 will be described.

[0132] The control unit 16 controls the hand shake correction performed by the shake correction actuator 21, the correction control unit 22, and the motion sensor 23, on the basis of the error amounts .DELTA.Ay and .DELTA.Ap obtained by the tracking control processing unit F1, by a function as the hand shake correction control processing unit F2.

[0133] The control unit 16 of the present example controls the hand shake correction on the basis of results obtained by comparing the movement control amounts as the error amounts .DELTA.Ay and .DELTA.Ap with threshold values. Specifically, the control unit 16 turns off the hand shake correction in a case where an error amount .DELTA.A (absolute value) exceeds a threshold value TH, and turns on the hand shake correction in a case where the error amount .DELTA.A is equal to or less than the threshold value TH, by using a threshold value THy and a threshold value THp set with respect to the error amounts .DELTA.Ay and .DELTA.Ap, respectively.

[0134] In the present example, the hand shake correction in each of the Yaw direction and the Pitch direction is independently controlled. That is, in the Yaw direction, if .DELTA.Ay>THy, the hand shake correction in the Yaw direction is turned off, and if .DELTA.Ay THy, the hand shake correction in the Yaw direction is turned on, on the basis of the result of comparing the error amount .DELTA.Ay (absolute value) with the threshold value THy. Furthermore, in the Pitch direction, if .DELTA.Ap>THp, the hand shake correction in the Pitch direction is turned off, and if .DELTA.Ap THp, the hand shake correction in the Pitch direction is turned on, on the basis of the result of comparing the error amount .DELTA.Ap (absolute value) with the threshold value THp.

[0135] FIG. 6 is a view for explaining an action by the hand shake correction control described above. Note that in each of FIGS. 6A and 6B, an outer frame represents an image frame of the captured image, and an inner frame represents the threshold value TH for the error amount .DELTA.A. Furthermore, each of arrows in FIGS. 6A and 6B indicates only the error amount .DELTA.Ay out of the error amounts .DELTA.Ay and .DELTA.Ap.

[0136] For example, in the Yaw direction, if the input error amount .DELTA.Ay (absolute) is equal to or less than the threshold value THy, the hand shake correction is turned on, as illustrated in FIG. 6A, and on the other hand, in a case where the input error amount .DELTA.Ay (absolute) exceeds the threshold value THy, the hand shake correction is turned off, as illustrated in FIG. 6B. Although not illustrated in FIGS. 6A and 6B, it is also similarly applied to the Yaw direction.

[0137] By such a hand shake correction control, for example, in a case where a user quickly changes a direction of the platform apparatus 10 according to a movement direction of the subject in a scene where a stationary tracking target subject starts to quickly move, the hand shake correction can be turned off, the hand shake correction can be prevented from working (acting) in a direction opposite to the movement direction of the subject, and tracking response can be prevented from deteriorating.

[0138] FIG. 7 is a flowchart illustrating a specific processing procedure to be executed by the control unit 16 to realize the hand shake correction control as the first embodiment as described above.

[0139] Note that the process illustrated in FIG. 7 is repeatedly executed for each frame of the captured image.

[0140] In FIG. 7, the control unit 16 determines whether or not the error amount .DELTA.Ay is greater than the threshold value THy in step S201, and if the error amount .DELTA.Ay is greater than the threshold value THy, the control unit 16 determines whether or not the error amount .DELTA.Ap is greater than the threshold value THp in step S202.

[0141] In a case where the error amount .DELTA.Ap is greater than the threshold value THp (that is, the movement control amounts in both the Yaw direction and the Pitch direction exceed the threshold values) in step S202, the processing proceeds to step S203, and the control unit 16 executes processing for turning off the hand shake correction in each of the Yaw direction and the Pitch direction. That is, the control unit 16 instructs the correction control unit 22 to turn off the hand shake correction in each of the Yaw direction (horizontal direction) and the Pitch direction (vertical direction).

[0142] On the other hand, in a case where the error amount .DELTA.Ap is not greater than the threshold value THp (that is, the movement control amount in only the Yaw direction exceeds the threshold value) in step S202, the processing proceeds to step S204, and the control unit 16 executes processing for turning off the hand shake correction in the Yaw direction and to turn on the hand shake correction in the Pitch direction.

[0143] Furthermore, in step S201, if the error amount .DELTA.Ay is not greater than the threshold value THy, the control unit 16 determines whether or not the error amount .DELTA.Ap is greater than the threshold value THp in step S205.

[0144] In a case where the error amount .DELTA.Ap is greater than the threshold value THp (that is, the movement control amount in only the Pitch direction exceeds the threshold value) in step S205, the processing proceeds to step S206, and the control unit 16 executes processing for turning on the hand shake correction in the Yaw direction and turning off the hand shake correction in the Pitch direction.

[0145] On the other hand, in a case where the error amount .DELTA.Ap is not greater than the threshold value THp (that is, the movement control amounts in both the Yaw direction and the Pitch direction are equal to or less than the threshold values) in step S205, the processing proceeds to step S207, and the control unit 16 executes processing for turning on the hand shake correction in each of the Yaw direction and the Pitch direction.

[0146] The process illustrated in FIG. 7 is terminated by executing the processing in step S203, S204, S206, or S207 by the control unit 16.

[0147] Note that in the process in FIG. 7, hysteresis can be added to the threshold values THy and THp to prevent chattering.

2. Second Embodiment

[0148] Subsequently, a second embodiment will be described.

[0149] In the second embodiment, the threshold value TH for the movement control amount is variable rather than fixed.

[0150] FIG. 8 is an explanatory view of an action by changing the threshold value TH.

[0151] First, a case where the threshold value TH is small is considered. As a value of the threshold value TH is small, the error amount .DELTA.A is likely to exceed the threshold value TH even though an error amount .DELTA.P of the position of the tracking target subject with respect to the target position in the captured image is small. That is, the smaller the threshold value TH, the less effective the hand shake correction is. Therefore, the hand shake correction effect is reduced. In FIG. 8, the smallest threshold value TH is represented as threshold values THy1 and THp1, but in a case where these threshold values THy1 and THp1 are set, the hand shake correction effect is minimized.

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