Imaging device, control method for the imaging device, and control program

Abstract

The present invention provides an imaging device that enables the capture of smooth, natural-looking images when photographing a subject by controlling at least one of the panning and tilting movements while zooming in / out. [Solution] The imaging device 10 comprises a lens unit LU, pan / tilt direction drive mechanisms 15a, 15b, a lens drive unit 13, a velocity waveform generation unit 19, and a pan / tilt speed correction calculation unit 20. The lens drive unit 13 adjusts the shooting range including the subject by changing the relative positions of multiple lenses included in the lens unit LU. The velocity waveform generation unit 19 generates a velocity waveform that shows the drive speed synchronized between the pan / tilt direction and the zoom position based on the amount of movement between the current position and the target position when moving from the current angle of view to the target position. The pan / tilt speed correction calculation unit 20 corrects the generated velocity waveform in the pan direction / tilt direction according to the change in focal length over time.

Description

Technical Field

[0001] The present disclosure relates to an imaging device that captures, for example, images and videos, a control method for the imaging device, and a control program.

Background Art

[0002] In recent years, for example, in a photography studio, a conference hall, an event venue, a sports facility, etc., a remote camera that performs photography while changing the shooting direction and shooting position by remote control has been used. For example, Patent Document 1 discloses a drive means for driving each function of a television camera, a shot storage means for storing position information of each function at a specific shooting position, a speed setting means for setting the transition speed of a video by speed or time, an angle-of-view input means for reading the current angle of view, a speed correction means for correcting the transition speed according to the angle of view, and a speed calculation means for calculating the moving speed of each function so as to end simultaneously with the transition time required for the transition from the current position to the target position. A remote control device for a television camera is disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the above conventional remote control device for a television camera has the following problems. That is, in the remote control device for a television camera disclosed in Patent Document 1, the zoom angle of view is read during the pan-tilt operation, and when the angle of view is small, the pan-tilt speed is automatically adjusted to be slow, and when the angle of view is large, the pan-tilt speed is automatically adjusted to be fast.

[0005] However, with this type of control, it was difficult to capture smooth, natural-looking footage because it did not allow for maintaining a constant ratio of change in the field of view and smoothly accelerating or decelerating when controlling pan and tilt movements while zooming in / out to photograph a subject. The object of this disclosure is to provide an imaging device, a control method for the imaging device, and a control program that can capture smooth, natural-looking images when photographing a subject while controlling at least one of panning and tilting movements while zooming in and out. [Means for solving the problem]

[0006] The imaging device according to this disclosure comprises a lens unit, an attitude adjustment mechanism, a zoom mechanism, a velocity waveform generation unit, and a control unit. The lens unit includes a plurality of lenses having optical axes. The attitude adjustment mechanism adjusts the orientation of the lens unit in at least one of the pan and tilt directions. The zoom mechanism adjusts the shooting range, including the subject, by changing the relative positions of the plurality of lenses included in the lens unit. The velocity waveform generation unit generates a velocity waveform that indicates the drive speed synchronized with the zoom position and at least one of the pan and tilt directions, based on the amount of movement between the current position and the target position when moving from the current angle of view to the target position. The control unit corrects the velocity waveform generated by the velocity waveform generation unit in at least one of the pan and tilt directions according to the change in focal length over time. [Effects of the Invention]

[0007] According to the imaging device described herein, when photographing a subject while controlling at least one of panning and tilting movements while zooming in / zooming out, it is possible to capture smooth, natural-looking images. [Brief explanation of the drawing]

[0008] [Figure 1] An overall perspective view showing the external configuration of an imaging device according to one embodiment of the present disclosure. [Figure 2] A control block diagram showing the internal configuration of the imaging device in Figure 1. [Figure 3A] Figure 1 shows the field of view when zooming in on an image taken with the imaging device shown in Figure 1. [Figure 3B] Figure 1 shows the field of view when zooming out during imaging with the imaging device shown in Figure 1. [Figure 4] This figure shows an example of the rate of change in the pan and tilt directions when moving from the current position to the target position while taking an image with the imaging device shown in Figure 1. [Figure 5] This graph shows the control mechanism used by the imaging device in Figure 1 to maintain a constant rate of change in the image when zooming in and taking pictures. [Figure 6] As a comparative example, this graph shows the relationship between the time elapsed and the rate of change in the image when shooting with an imaging device while increasing the zoom ratio and keeping the drive speed constant in the pan and tilt directions. [Figure 7] This graph shows the relationship between the passage of time and the drive speed in the pan and tilt directions when taking images with the imaging device shown in Figure 1 while increasing the zoom ratio and maintaining a constant rate of change in the image. [Figure 8A] Figure 1 shows a trapezoidal velocity waveform graph illustrating the relationship between the passage of time and the drive speed in the pan and tilt directions when taking images with the imaging device shown in Figure 1 while zooming in and maintaining a constant rate of change in the image. [Figure 8B] Figure 8A shows the speed waveform and graph illustrating the drive speed multiplier in the pan and tilt directions relative to the zoom position when shooting while increasing the zoom ratio. [Figure 8C] This graph shows a constant screen change rate speed waveform generated by multiplying the trapezoidal speed waveform in Figure 8A by the speed multiplier in Figure 8B. [Figure 9A] This graph shows the difference between the calculated position in the pan and tilt directions, obtained by integrating the trapezoidal velocity waveform in Figure 8C, and the target position. [Figure 9B] A graph showing the velocity waveform in Figure 8C corrected to compensate for the difference between the calculation result in Figure 9A and the target position. [Figure 10A]A diagram showing a state where the target position angle is within the range of the current position angle. [Figure 10B] A diagram showing a state where the target position angle is outside the range of the current position angle. [Figure 11A] A diagram showing that when calculating the target position after zooming out from the target position, a zoom reference position is set at one point when the wide end of the target position is smaller than the zoom wide end angle. [Figure 11B] A diagram showing that when calculating the target position after zooming out from the target position, two reference points are set when the wide end of the target position is larger than the zoom wide end angle. [Figure 12] A diagram explaining the process of checking whether the target position angle is within the range of the current position angle. [Figure 13] A diagram explaining the process of examining in which of the four areas separated by the diagonal line of the current position the target position exists when the target position angle is outside the range of the current position angle. [Figure 14A] A diagram explaining the process of determining whether two reference points are required based on the left end when calculating the target position after zooming out from the target position and the target position angle is larger than the zoom wide end angle. [Figure 14B] A diagram explaining the process of determining whether two reference points are required based on the lower end when calculating the target position after zooming out from the target position and the target position angle is larger than the zoom wide end angle. [Figure 15] A diagram explaining the process of obtaining the zoom-out end position from the current position and the zoom-in start position of the target position angle based on the lower end when the target position angle is larger than the zoom wide end angle. [Figure 16A] A graph showing the speed waveform from the current position to the zoom-out end position. [Figure 16B] A graph showing the speed waveform from the zoom-in start position towards the target position to the target position. [Figure 16C] A graph showing the speed waveform from the zoom-out end position to the zoom-in start position. [Figure 17]A graph showing a composite waveform generated by combining the velocity waveforms from Figures 16A, 16B, and 16C. [Figure 18] This figure shows the correspondence between the screen movement range and zoom angle range and the velocity waveform in Figure 17. [Figure 19] A flowchart showing the processing flow of the control method for the imaging device disclosed herein. [Figure 20] A flowchart showing the flow of the calculation process for the zoom position among the processing steps of the control method for the imaging device of this disclosure. [Figure 21] A flowchart showing the process flow for calculating the coordinates of the zoom position, which is part of the control method for the imaging device described herein. [Figure 22] A flowchart showing the processing flow of the angle-of-view edge reference calculation, which is part of the control method for the imaging device of this disclosure. [Modes for carrying out the invention]

[0009] The embodiments will be described in detail below, with reference to the drawings as appropriate. However, unnecessary details may be omitted. For example, detailed explanations of already well-known matters and redundant explanations of substantially identical configurations may be omitted. This is to avoid the following explanation becoming unnecessarily verbose and to facilitate understanding for those skilled in the art. The applicant provides the accompanying drawings and the following description so that a person skilled in the art can fully understand the disclosure, and not intends to limit the subject matter described in the claims.

[0010] (Embodiment 1) An imaging device 10 according to one embodiment of this disclosure will be described below with reference to Figures 1 to 22. (1) Overall configuration of the imaging device 10 The imaging device 10 according to this embodiment is installed, for example, in a photography studio, conference hall, event venue, sports facility, etc., and is controlled by a controller such as a PC (Personal Computer) to perform various types of photography. As shown in Figure 1, the imaging device 10 performs photography while switching the shooting direction in the pan, tilt, and roll directions. Furthermore, as shown in Figure 1, the imaging device 10 has a lens unit LU containing multiple optical lenses built into the camera head 11, and performs photography by changing the shooting range (zoom range) and focus position by controlling the relative position of the optical lenses.

[0011] In this embodiment, the imaging device 10 controls panning and tilting movements while zooming in and out to capture a subject, and in order to capture smooth images without any unnaturalness, it zooms out before moving to the target position and performs panning and tilting movements, creating a section that is synchronized with the zoom. In addition, it corrects the orientation of the camera head unit 11 while shooting so that it tracks the subject within the shooting range of the camera head unit 11.

[0012] Furthermore, the imaging device 10 performs constant movement control relative to the camera angle of view in order to achieve shooting in which the zoom angle of view changes uniformly while accelerating and decelerating smoothly. Furthermore, the imaging device 10 compares target position information with current position information to calculate the optimal control switching points for pan-tilt and zoom operations in order to capture smooth images, and performs overlap processing to connect the acceleration and deceleration sections of the generated velocity waveform.

[0013] When switching the shooting range from the field of view at the current position to the field of view at the target position, the target position is, for example, pre-set, and the shooting range moves from the current position to the target position by inputting a predetermined operation from the controller, etc. (for example, pressing a predetermined button). Furthermore, the target position refers to the zoom position, pan direction, and tilt direction that determine the target field of view, and as mentioned above, it is assumed that these are pre-set.

[0014] As shown in Figures 1 and 2, the imaging device 10 includes a base unit 10a, a swivel unit 10b, a camera head unit 11, a rotation mechanism 11a, an image sensor 12, a lens drive unit (zoom mechanism) 13, a lens control unit (control unit) 14, a pan direction drive mechanism (attitude adjustment mechanism) 15a, a tilt direction drive mechanism (attitude adjustment mechanism) 15b, a pan / tilt direction control unit 16, a field of view range determination unit (control unit) 17, a zoom position coordinate generation unit 18, a velocity waveform generation unit 19, a pan / tilt velocity correction calculation unit (control unit) 20, and a position correction velocity calculation unit (control unit) 21.

[0015] As shown in Figure 1, the base portion 10a is a component that constitutes the lower part of the imaging device 10, and is configured so that the swivel portion 10b is driven to swivel relative to the base portion 10a by the pan direction drive mechanism 15a. As shown in Figure 1, the swivel section 10b is an arm-shaped member attached to the base section 10a in a swivelable manner. Its lower part is connected to the base section 10a, and its upper part supports the camera head section 11 in a rotatable manner.

[0016] The camera head 11 is a substantially cylindrical member that encloses a lens unit LU containing multiple optical lenses and an image sensor 12. As shown in Figure 1, the camera head 11 is driven to rotate in the pan direction by a pan direction drive mechanism 15a and to change its orientation up and down in the tilt direction by a tilt direction drive mechanism 15b. Furthermore, as shown in Figure 1, the camera head 11 is driven to rotate in the roll direction by a rotation mechanism (not shown).

[0017] This allows the imaging device 10 to perform imaging while switching the direction of imaging (pan / tilt / roll direction). The rotation mechanism 11a rotates the camera head 11 around the roll axis X shown in Figure 1. This allows the image to be rotated while shooting a subject. As shown in Figure 2, the image sensor 12 is located in the camera head 11 and converts light that has entered through a lens unit LU, which includes multiple optical lenses such as a zoom lens, into a signal to generate digital image data of the subject.

[0018] The lens drive unit 13 is housed within the camera head unit 11 and drives the lens unit LU, which includes multiple optical lenses such as a zoom lens, to change its relative position. This allows for adjustment of the focal point relative to the subject and changes the shooting range (zoom range) that includes the subject. The lens control unit (control unit) 14 controls the lens drive unit 13 to adjust the shooting range and focus position by changing the relative positions in the optical axis direction of multiple lenses, such as zoom lenses and focus lenses, included in the lens unit LU.

[0019] As shown in Figure 1, the pan-direction drive mechanism (attitude adjustment mechanism) 15a rotates the camera head 11 and the swivel unit 10b relative to the base 10a. This allows for shooting while changing the shooting direction in the left-right direction relative to the subject. As shown in Figure 1, the tilt-direction drive mechanism (attitude adjustment mechanism) 15b rotates the camera head 11 in the vertical direction relative to the swivel section 10b. This allows for shooting while changing the shooting direction in the vertical direction relative to the subject.

[0020] The pan / tilt direction control unit 16 controls the pan direction drive mechanism 15a and the tilt direction drive mechanism 15b so that when the zoom position (shooting range) changes due to the lens drive unit 13 controlled by the lens control unit 14, smooth footage is shot while the subject remains within the field of view. The field of view range determination unit (control unit) 17 determines whether the field of view at the target position is within the range of the field of view at the current position when moving the shooting direction from the field of view at the current position to the field of view at the target position.

[0021] The zoom position coordinate generation unit 18 determines the number of zoom position points (1 point (the target position's field of view is within the wide-angle range) or 2 points (the target position's field of view is outside the wide-angle range)) according to the determination result in the field of view range determination unit 17, and calculates and generates the coordinates of the zoom position. The velocity waveform generation unit 19 generates a trapezoidal velocity waveform synchronized with the pan / tilt direction and zoom position based on the amount of movement (distance) between the current position and the target position, in the section from the field of view of the current position to the field of view of the target position, which includes the section from the zoom start position of the current position to the zoom end position of the target position generated by the zoom position coordinate generation unit 18.

[0022] The pan / tilt speed correction calculation unit (control unit) 20 corrects the speed waveforms in the pan and tilt directions for the trapezoidal speed waveform generated by the speed waveform generation unit 19, according to the change in focal length (zoom magnification) over time. The position correction speed calculation unit (control unit) 21 further corrects the speed waveform corrected by the pan / tilt speed correction calculation unit 20 so that it reaches the target position from the current position.

[0023] In other words, if the drive speed of the pan / tilt drive mechanisms 15a and 15b is adjusted by multiplying it by the reciprocal of the zoom magnification so that the rate of change of the screen remains constant, the speed of the drive axis (motor axis) (drive speed) will decrease as the zoom increases, and there is a risk that the shooting range will not reach the target position. Therefore, in the imaging device 10 of this embodiment, the position correction speed calculation unit 21 integrates the drive speed adjusted so that the screen (angle of view) change rate is constant, calculates how much distance is actually lacking, and then multiplies the drive speed adjusted so that the screen change rate is constant by the ratio of the distance that must be moved to reach the target position, which is calculated by comparing the distance moved with the distance actually moved calculated by integration.

[0024] This allows for smooth acceleration and deceleration while maintaining a uniform change in the zoom angle of view. This is achieved by controlling the amount of movement relative to the camera's angle of view to be constant, and by preventing the shooting range from failing to reach the target position. <Constant control of screen change rate> In the imaging device 10 of this embodiment, as described above, shooting is performed in which the zoom angle of view changes uniformly while smooth acceleration and deceleration are performed.

[0025] Here, there is a difference between the field of view when zooming in and when zooming out, as shown in Figures 3A and 3B. Specifically, the field of view narrows when zooming in, as shown in Figure 3A, and widens when zooming out, as shown in Figure 3B. Therefore, since the field of view narrows when zooming in and widens when zooming out, the drive speed of the pan / tilt drive mechanisms 15a and 15b is controlled in accordance with the change in zoom position (change in field of view).

[0026] Furthermore, as shown in Figure 4, for example, when moving the shooting range from the current position (solid line) to the target position (dotted line), the rate of screen change per second in the pan direction is 50%, and the rate of screen change per second in the tilt direction is 75%. Therefore, the imaging device 10 of this embodiment controls the pan-direction drive mechanism 15a and the tilt-direction drive mechanism 15b so that the respective rate of change of the screen in the pan-direction and tilt-direction is substantially constant.

[0027] In this embodiment, when controlling the speed in the pan / tilt direction so that the screen change rate remains constant, the zoom speed is controlled to be synchronized, as shown in Figure 5. Here, if we define zoom speed as the rate of change of focal length per unit time, then if the zoom speed is 1.2x / second (a speed at which the focal length of 10mm becomes 12mm after 1 second), then after 2 seconds the focal length will be 12mm × 1.2x = 14.4mm, and after 3 seconds the focal length will be 14.4mm × 1.2x = 17.28mm.

[0028] The focal length per unit time is expressed by the following relationship: Focal length L(n)=L(n-1)×η_z t_s However, η_z is the zoom speed, t_s is the sampling time, θ(n) is the field of view, and the camera field of view θ(n) = wide field of view / zoom magnification. In this case, the expected average screen change rate can be expressed by the following relationship.

[0029] Average screen change rate = Average drive speed / ((Zoom end angle × (1 - zoom speed ratio) サンプル数 ) / (1-zoom speed ratio) / (number of samples) The following formulas are used: screen change rate = drive speed (deg / sec) / camera field of view (deg), drive speed = camera field of view (deg) × screen change rate, calculated drive movement amount = ∫ drive speed, target position error magnification = target movement amount / calculated drive position movement amount, and corrected drive speed = drive speed × target position error magnification.

[0030] For example, in a comparative example, when the drive speeds of the pan-direction drive mechanism 15a and the tilt-direction drive mechanism 15b are kept constant, as shown in Figure 6, the rate of change in the screen increases as the zoom-in progresses over time, which may result in an unsmooth image. In the imaging device 10 of this embodiment, the trapezoidal velocity waveform generated by the velocity waveform generation unit 19 is used to control the drive speeds of the pan-direction drive mechanism 15a and the tilt-direction drive mechanism 15b based on a corrected velocity waveform, as shown in Figure 7. The speeds are large at the rise and decrease as time progresses and the device zooms in.

[0031] In other words, as shown in Figure 8A, the velocity waveform generation unit generates a trapezoidal velocity waveform that includes the drive speeds of each axis of the pan drive mechanism 15a, the tilt drive mechanism 15b, and the lens drive unit 13, based on the amount of movement / maximum speed / acceleration, so as to synchronize the drive in the pan, tilt, and zoom directions. Then, as shown in Figure 8B, the pan / tilt speed correction calculation unit 20 calculates the speed multiplier in the pan / tilt direction with respect to the zoom focal position (zoom magnification) so as the zoom magnification increases over time, the drive speed multiplier in the pan / tilt direction decreases.

[0032] Furthermore, if the zoom magnification decreases over time, the pan / tilt speed correction calculation unit 20 calculates the speed magnification in the pan / tilt direction relative to the zoom position, in the opposite direction to the speed waveform shown in Figure 8B, so as to increase the drive speed magnification in the pan / tilt direction. Next, the pan / tilt speed correction calculation unit 20 multiplies the trapezoidal speed waveform shown in Figure 8A by the speed multiplier in the pan / tilt direction shown in Figure 8B to generate the constant field of view speed waveform shown in Figure 8C.

[0033] This allows for smooth video capture while maintaining a nearly constant rate of screen change, for example, when moving from the current position to the target position while zooming in, by multiplying the trapezoidal velocity waveform by the reciprocal of the zoom magnification and changing the drive speed of the pan / tilt drive mechanisms 15a and 15b in the pan / tilt direction. Furthermore, in the imaging device 10 of this embodiment, in order to resolve the situation where the arrival position does not reach the target position as a result of control according to the velocity waveform shown in Figure 8C, the position correction velocity calculation unit 21 integrates the trapezoidal velocity waveform to calculate the arrival position and calculates the ratio of the target position to the arrival position.

[0034] As shown in Figure 9A, the position correction speed calculation unit 21 performs position correction in the pan direction to eliminate the difference between the reached position and the target position in the pan direction, which are calculated by integrating the speed waveform shown in Figure 8C. Similarly, as shown in Figure 9A, the position correction speed calculation unit 21 performs position correction in the tilt direction to eliminate the difference between the reached position and the target position in the tilt direction, which are calculated by integrating the speed waveform shown in Figure 8C.

[0035] The position correction speed calculation unit 21 then multiplies the constant field-of-view speed waveform by the position correction ratio to generate a final speed waveform that has a substantially constant screen change rate and can reach the target position, as shown in Figure 9B. <If the field of view of the target location is outside the field of view of the current location> In the imaging device 10 of this embodiment, it is determined whether the field of view of the target position is within or outside the field of view of the current position, and if it is outside the range, the following control is performed.

[0036] In other words, in the imaging device 10 of this embodiment, first, the field of view range determination unit 17 determines whether the field of view of the target position is within the range of the field of view of the current position (see Figure 10A) or outside the range (see Figure 10B). Specifically, the field of view range determination unit 17 determines that the target position is outside the range of the current field of view if the distance between the first end of the current field of view and the second end of the target position opposite the first end is greater than the field of view of the wide end of the lens drive unit 13.

[0037] In this case, when moving from a zoomed-in subject at the current position to a target position that includes another zoomed-in subject outside the screen while shooting remains ON, the camera switches to zoom-out panning mode, which controls the pan / tilt drive mechanisms 15a and 15b while decreasing the zoom magnification, as shown in Figure 10B. In other words, in the imaging device 10 of this embodiment, in order to capture natural-looking images as if taken by a cameraman (person), when switching the subject from a zoomed-in subject at the current position to another zoomed-in subject at a target position outside the screen, the device first zooms out from the current position and then zooms in towards the subject at the target position.

[0038] In this process, smooth video can be captured by implementing the aforementioned constant screen change rate control during the steps of zooming out from the current position, moving in the pan / tilt direction, and zooming in to the target position. Here, the field of view determination unit 17 determines whether the target position is larger than the zoom wide-end field of view when calculating the target position after zooming out from the target position.

[0039] For example, when calculating a target position zoomed out from the target position, if the field of view of the target position is smaller than the field of view at the widest zoom end, the constant screen change rate control described above is performed in the range less than the widest zoom end, as shown in Figure 11A. On the other hand, if the field of view of the target position is larger than the field of view at the widest zoom end, as shown in Figure 11B, the end position of zooming out from the current position and the start position of zooming in to the target position are different. Therefore, the center position at the widest zoom end of the current position (first center position) and the center position at the widest zoom end of the target position (second center position) are in different locations.

[0040] For example, if the relationship between the distance between the left edge of the current position and the right edge of the target position is less than the angle of view at the wide-angle end, it means that the target position is within the range of the zoom-out limit. In this case, the zoom position coordinate generation unit 18 calculates the coordinates of the wide-angle end near the current position. On the other hand, if the relationship between the distance between the left edge of the current position and the right edge of the target position is greater than the angle of view at the wide-angle end, it means that the target position is outside the limit of zooming out. Therefore, in this case, the zoom position coordinate generation unit 18 calculates the coordinates of the wide-angle end when zooming out near the target position.

[0041] Here, we will explain the process by which the field of view determination unit 17 determines whether the field of view of the target position is within or outside the field of view of the current position. As shown in Figure 12, the coordinates of the four corners of the wide-angle edge at the current position are A=(Ax,Ay), B=(Bx,By), C=(Cx,Cy), and D=(Dx,Dy), and the coordinates of the four corners of the field of view at the target position are a=(ax,ay), b=(bx,by), c=(cx,cy), and d=(dx,dy).

[0042] In this case, the condition for the field of view of the target position to be within the field of view of the current position is: Ax-ax<0, Ay-ay>0 Bx-bx<0,By-by<0 Cx-cx>0,Cy-cy<0 Dx-dx>0, Dy-dy>0 The condition is that the following eight relationships are satisfied.

[0043] Therefore, the field of view determination unit 17 determines that the field of view of the target position is within the field of view of the current position if the above eight conditions are met, and determines that the field of view of the target position is outside the field of view of the current position if the conditions are not met. Next, the field of view determination unit 17 determines that if the above eight conditions are not met, the field of view of the target position is outside the field of view of the current position. Then, the zoom position coordinate generation unit 18 determines which side of the four areas (see Figure 13) the field of view of the current position is located on, separated by diagonal lines.

[0044] Here, since there is no way to simultaneously determine which side of the area divided by the diagonal of the field of view of the current position the target position is located on, the imaging device 10 of this embodiment first determines which side of the four areas—upper right, upper left, lower right, and lower left—the target position is located on, as shown in Figure 13. As shown in Figure 13, if the center of the field of view at the current position is O(Ox,Oy) and the center of the field of view at the target position is o(ox,oy), then if Ox-ox>0, the target position is determined to be to the left of the current position. If Ox-ox<0, the target position is determined to be to the right of the current position. Similarly, if Oy-oy>0, the target position is determined to be below the current position. If Oy-oy<0, the target position is determined to be above the current position.

[0045] Next, the zoom position coordinate generation unit 18 compares the slope of the diagonal of the field of view at the current position (α) with the slope of the straight line connecting the centers of the field of view at the current position and the field of view at the target position (β), and determines the reference position for aligning the screen edge based on whether each is on the upper or lower side. α = (Dy - Cy) / (Cx - Bx) β = (oy - Oy) / (ox - Ox) For example, in the case of the upper right, if the slope of the diagonal of the current position (α) is greater than the slope (β) of the straight line connecting the center of the current position and the center of the target position (α>β), the left edge of the field of view of the current position is used as the reference point. On the other hand, if the slope of the diagonal of the current position (α) is less than the slope (β) of the straight line connecting the center of the current position and the center of the target position (α<β), the bottom edge of the field of view of the current position is used as the reference point.

[0046] Similarly, in the case of the upper left, if the slope of the diagonal of the current position (β) is smaller than the slope of the straight line connecting the center of the current position and the center of the target position (-α) (-α > β), the right edge of the field of view of the current position is used as the reference point. On the other hand, if the slope of the diagonal of the current position (β) is larger than the slope of the straight line connecting the center of the current position and the center of the target position (-α) (-α < β), the lower edge of the field of view of the current position is used as the reference point.

[0047] Similarly, in the case of the lower right, if the slope of the diagonal of the current position (β) is smaller than the slope of the straight line connecting the center of the current position and the center of the target position (-α) (-α > β), the left edge of the field of view of the current position is used as the reference point. On the other hand, if the slope of the diagonal of the current position (β) is larger than the slope of the straight line connecting the center of the current position and the center of the target position (-α) (-α < β), the top edge of the field of view of the current position is used as the reference point.

[0048] Similarly, in the case of the lower left, if the slope of the diagonal of the current position (β) is smaller than the slope (α) of the straight line connecting the center of the current position and the center of the target position (α), then the right edge of the field of view of the current position is used as the reference point. On the other hand, if the slope of the diagonal of the current position (β) is larger than the slope (α) of the straight line connecting the center of the current position and the center of the target position (α), then the top edge of the field of view of the current position is used as the reference point.

[0049] Next, the zoom position coordinate generation unit 18 determines whether the target position is greater than the field of view at the zoom wide end when calculating the target position by subtracting the zoom from the target position. If the target position is smaller than the field of view at the zoom wide end, the points where zooming out is possible are limited to that zoom position. The zoom wide end can be set arbitrarily. Here, as shown in Figure 14A, if the conditions |Ax-dx|>Xmax are not met when the right edge is used as the reference point, or |ax-Dx|>Xmax when the left edge is used as the reference point, the zoom target position is set to the wide-angle end.

[0050] Similarly, as shown in Figure 14B, when the upper end is used as the reference point, |ay-By|>Ymax, If the lower end is used as the reference point, and the condition |Ay-by| > Ymax is not met, the zoom target position is set to the wide-angle end. Next, when determining the zoom-out end position P1 from the current position shown in Figure 15, if the left-right axis is the reference, the x-axis direction (pan direction) is important. Therefore, the x-axis coordinate is calculated, and the y-axis coordinate is calculated using the following linear equation, which is a point on the straight line (Oo line) connecting the center of the current position and the center of the target position. Similarly, if the up-down axis is the reference, the y-axis direction (tilt direction) is important. Therefore, the y-axis coordinate is calculated first, and then the x-axis coordinate position on the straight line is calculated using the following linear equation.

[0051] y = (oy - Oy) / (ox - Ox)x + h x = (yh) / (ox - Ox) / (oy - Oy) Similarly, the starting position P2 for zooming in to the target position shown in Figure 15 also has a specific order for calculation based on both left / right and up / down. However, the signs for adding the coordinates corresponding to the wide-angle end are reversed between right and left, and up and down.

[0052] Specifically, when using the rightmost edge as the reference point, Ax and Bx are fixed, Px = Ox - Xmax / 2, Py For example, if the left edge is used as the reference point, Dx and Cx are fixed, Px = Ox + Xmax / 2, Py For example, if the upper end is used as the reference point, By and Cy are fixed, Py = Oy - Ymax / 2, Px For example, if the lower end is used as the reference point, Ay and Dy are fixed, Py = Oy + Xmax / 2, Px This is the result.

[0053] <Generation and Synthesis of Velocity Waveforms> In the imaging device 10 of this embodiment, if it is determined that the field of view of the target position is outside the field of view of the current position, the velocity waveform generation unit 19 will (a) Velocity waveform (first velocity waveform) for the section from the current position to the zoom-out end position (first control section), (b) Velocity waveform (third velocity waveform) for the section from the zoom-out end position to the zoom-in start position (second control section), (c) Velocity waveform (second velocity waveform) for the section from the zoom-in start position to the target position. These are generated separately. Then, the velocity waveform generation unit 19 generates a composite velocity waveform by connecting the velocity waveforms of (a) and (b), and the velocity waveforms of (b) and (c), respectively.

[0054] More specifically, the velocity waveform generation unit 19 first generates a trapezoidal velocity waveform (see dotted line in Figure 16A) in the section from the current position to the zoom-out end position, and then performs calculations to correct the velocity waveform according to the change in focal length (zoom magnification) over time so that the screen change rate remains constant, thereby generating a velocity waveform (see solid line in Figure 16A). Next, as shown in Figure 16B, the velocity waveform generation unit 19 similarly generates a trapezoidal velocity waveform (see dotted line in the figure) in the section from the zoom-in start position to the target position, and also performs calculations to correct the velocity waveform according to the change in focal length (zoom magnification) over time so that the screen change rate remains constant, thereby generating a velocity waveform (see solid line in the figure).

[0055] In this process, in order to connect smooth velocity waveforms without stopping the pan / tilt drive mechanisms 15a and 15b at the end of zoom-out and the start of zoom-in, the area of ​​the arrow portion (deceleration portion) in Figure 16A and the area of ​​the arrow portion (acceleration portion) in Figure 16B are added to the amount of movement in the section from the end of zoom-out to the start of zoom-in to generate the velocity waveform shown in Figure 16C.

[0056] The velocity waveform generation unit 19 sets the maximum velocity of the velocity waveform shown in Figure 16A as the initial velocity and the maximum velocity of the velocity waveform shown in Figure 16B as the final velocity to generate the velocity waveform shown in Figure 16C. Then, in order to smoothly connect the generated velocity waveforms (a) and (b) (Figures 16A and 16C), the deceleration portion of the zoom-out section of velocity waveform (a) and the acceleration portion of velocity waveform (b) are time-overlapped, and a composite waveform is generated by combining the velocity waveforms of Figures 16A and 16C.

[0057] Similarly, the acceleration portion at the start of zooming in (c) and the deceleration portion (b) are time-overlapped to generate a composite waveform by combining the velocity waveforms in Figure 16C and Figure 16B. As a result, the velocity waveform generation unit 19 generates a final composite waveform, as shown in Figure 17, enabling the capture of smooth, natural-looking footage when controlling panning and tilting movements while zooming in and out to photograph a subject.

[0058] Figure 18 shows a diagram overlaid with the screen movement range, zoom angle range, and velocity waveform when moving to the target position by driving in the pan / tilt direction while zooming out from the current position, and then driving in the pan / tilt direction while zooming in towards the target position. As shown in Figure 18, from the current position to the zoom-out end position (sections I and II in the figure), a pan / tilt operation with zoom is performed. From the zoom-out end position to the zoom-in start position (sections III, IV, and V in the figure), a pan / tilt operation without zoom is performed. Then, from the zoom-in start position to the target position (sections VI and VII in the figure), a pan / tilt operation with zoom is performed again.

[0059] As described above, in order to smoothly perform a series of shots from the current position to the target position, it is possible to generate a continuous velocity waveform in the section from I to VII shown in Figure 18 without stopping the pan / tilt operation even once. <Control method for imaging device 10> The control method for the imaging device 10 of this embodiment will be explained below using the flowcharts in Figures 19 to 22.

[0060] In other words, in the imaging device 10 of this embodiment, as shown in Figure 19, first, in step S11, the field of view range determination unit 17 determines whether or not the field of view of the target position is within the range of the field of view of the current position. If it is determined that the field of view of the target position is within the range of the field of view of the current position, the process proceeds to step S12. On the other hand, if it is determined that the field of view of the target position is outside the range of the field of view of the current position, the process proceeds to step S14.

[0061] Next, in step S12, since it was determined in step S11 that the field of view of the target position is within the range of the field of view of the current position, the velocity waveform generation unit 19 generates a trapezoidal velocity waveform shown by the dotted line in Figure 16A. Next, in step S13, the pan / tilt speed correction calculation unit 20 generates a speed waveform (see the solid waveform in Figure 16A) with the drive speed in the pan / tilt direction corrected so that the rate of change of the screen remains constant during the zoom operation described above, and then terminates the process.

[0062] This allows for the capture of images with a constant rate of change by setting a high drive speed in the pan / tilt direction when the zoom magnification is high, and then decreasing the drive speed in the pan / tilt direction as the zoom magnification decreases, thereby generating a speed waveform. On the other hand, in step S14, since it was determined in step S11 that the field of view of the target position is outside the field of view of the current position, the zoom position coordinate generation unit 18 performs calculations for the screen edge position.

[0063] Next, in step S15, the zoom position coordinate generation unit 18 determines whether the zoom-out end position and the zoom-in start position are the same position (1 point) or different positions (2 points). The calculation process for the screen edge position and the process for determining the number of points for the zoom position will be described in detail later using Figure 20. Next, in step S16, the zoom position coordinate generation unit 18 calculates the coordinates of the zoom-out end position.

[0064] Next, in step S17, the velocity waveform generation unit 19 generates a trapezoidal velocity waveform (see the dotted waveform in Figure 16A) that synchronizes the zoom operation with the drive speed in the pan / tilt direction for the section from the current position to the zoom-out end position. Next, in step S18, similar to step S13, the pan / tilt speed correction calculation unit 20 generates a speed waveform (see the solid waveform in Figure 16A) that corrects the drive speed in the pan / tilt direction so that the rate of change of the screen remains constant during the zoom operation described above.

[0065] Next, in step S19, the velocity waveform generation unit 19 generates a trapezoidal velocity waveform (see the dotted waveform in Figure 16B) that synchronizes the zoom operation with the drive speed in the pan / tilt direction in the section from the zoom-in start position to the target position. Next, in step S20, similar to steps S13 and S18, the pan / tilt speed correction calculation unit 20 generates a speed waveform (see the solid waveform in Figure 16B) that corrects the drive speed in the pan / tilt direction so that the rate of change of the screen remains constant during the zoom operation described above.

[0066] Next, in step S21, the area of ​​the deceleration portion at the zoom-out end position and the area of ​​the acceleration portion at the zoom-in start position are added together. Next, in step S22, the velocity waveform generation unit 19 synthesizes the velocity waveforms shown in Figures 16A, 16B, and 16C described above to generate the synthesized waveform shown in Figure 17, and then terminates the process.

[0067] This allows for smooth and seamless video recording when, in situations where the target location is outside the field of view of the current location, the camera zooms out from the current location and then zooms in again towards the target location. <Zoom position point determination process> Next, the details of the calculation process at the edge of the screen in step S14 and the score determination process for the zoom position in step S15 will be explained using the flowchart in Figure 20 as follows.

[0068] In other words, as shown in Figure 20, in step S31, the zoom position coordinate generation unit 18 determines the reference position. In the following steps S32, S36, S40, and S44, we will describe the case in which the zoom position coordinate generation unit 18 determines the right end, left end, top end, and bottom end as the reference positions, respectively. Next, in step S32, based on the result of the determination in step S31, the zoom position coordinate generation unit 18 sets the right edge of the screen as the reference position.

[0069] Next, in step S33, the zoom position coordinate generation unit 18 calculates the target position by subtracting the zoom from the target position, using the rightmost edge as a reference, and determines whether the width of the target position is greater than the field of view at the zoom wide end. If the width of the target position is greater than the field of view at the zoom wide end, the process proceeds to step S34; otherwise, the process proceeds to step S35. Next, in step S34, since it was determined in step S33 that the target position is wider than the field of view at the zoom wide end, it is determined that the zoom-out position and zoom-in position are separate, and that there are two zoom positions, and the process ends.

[0070] On the other hand, in step S35, since it was determined in step S33 that the target position is narrower than the field of view at the widest zoom setting, the zoom position is determined to be one point, and the process ends. Next, in step S36, based on the result of the determination in step S31, the zoom position coordinate generation unit 18 sets the left edge of the screen as the reference position.

[0071] Next, in step S37, the zoom position coordinate generation unit 18 calculates the target position by subtracting the zoom from the target position, using the left edge as a reference, and determines whether the width of the target position is greater than the field of view at the zoom wide end. If the width of the target position is greater than the field of view at the zoom wide end, the process proceeds to step S38; otherwise, the process proceeds to step S39. Next, in step S38, since it was determined in step S37 that the target position is wider than the field of view at the zoom wide end, it is determined that the zoom-out position and zoom-in position are separate, and that there are two zoom positions, and the process ends.

[0072] On the other hand, in step S39, since it was determined in step S37 that the target position is narrower than the field of view at the widest zoom setting, the zoom position is determined to be one point, and the process ends. Next, in step S40, based on the result of the determination in step S31, the zoom position coordinate generation unit 18 sets the top edge of the screen as the reference position.

[0073] Next, in step S41, the zoom position coordinate generation unit 18 calculates the target position by subtracting the zoom from the target position, using the upper end as a reference, and determines whether the height of the target position is greater than the field of view at the zoom wide end. If the height of the target position is greater than the field of view at the zoom wide end, the process proceeds to step S42; otherwise, the process proceeds to step S43. Next, in step S42, since it was determined in step S41 that the target position is greater in height than the field of view at the wide-angle end of the zoom, it is determined that there are two zoom positions, with the zoom-out position and zoom-in position being different, and the process ends.

[0074] On the other hand, in step S43, since it was determined in step S41 that the height of the target position is less than the field of view at the widest zoom setting, the zoom position is determined to be 1 point, and the process ends. Next, in step S44, based on the result of the determination in step S31, the zoom position coordinate generation unit 18 sets the bottom edge of the screen as the reference position.

[0075] Next, in step S45, the zoom position coordinate generation unit 18 calculates the target position by subtracting the zoom from the target position, using the lower end as a reference, and determines whether the height of the target position is greater than the field of view at the zoom wide end. If the height of the target position is greater than the field of view at the zoom wide end, the process proceeds to step S46; otherwise, the process proceeds to step S47. Next, in step S46, since it was determined in step S45 that the target position is greater in height than the field of view at the widest zoom end, it is determined that the zoom-out position and zoom-in position are separate, and that there are two zoom positions, and the process ends.

[0076] On the other hand, in step S47, since it was determined in step S45 that the height of the target position is less than the field of view at the widest zoom end, the zoom position is determined to be 1 point, and the process ends. <Coordinate calculation processing for zoom position> Next, the details of the coordinate calculation process for the zoom position in step S16 will be explained using the flowchart in Figure 21 as follows.

[0077] In other words, as shown in Figure 21, in step S51, the zoom position coordinate generation unit 18 calculates the count of a linear equation on the target position line. Next, in step S52, the zoom position coordinate generation unit 18 determines the reference position. Steps S53, S57, S61, and S65 describe the case where the zoom position coordinate generation unit 18 determines the right edge, left edge, top edge, and bottom edge as the reference position, respectively.

[0078] Next, in step S53, based on the result of the determination in step S52, the zoom position coordinate generation unit 18 sets the right edge of the screen as the reference position. Next, in step S54, the zoom position coordinate generation unit 18 calculates the X coordinate of the first point (zoom-out end position) as (current position center - horizontal field of view / 2) and the Y coordinate as the coordinate on the straight line Oo in Figure 14A (Px=Ox-Xmax / 2, Py).

[0079] Next, in step S55, it is determined whether the reference position consists of two points. If it is determined that the reference position consists of two points, the process proceeds to step S56. If it is determined that the reference position consists of one point, the process ends because its coordinates have already been calculated in step S54. Next, in step S56, the X-coordinate of the second point (zoom-in starting position) is calculated as (current position center + horizontal field of view / 2), and the Y-coordinate is calculated as the coordinate on the straight line of line Oo in Figure 14A (Px=Ox-Xmax / 2, Py), and the process ends.

[0080] Next, in step S57, based on the result of the determination in step S52, the zoom position coordinate generation unit 18 sets the left edge of the screen as the reference position. Next, in step S58, the zoom position coordinate generation unit 18 calculates the X coordinate of the first point (zoom-out end position) as (current position center + horizontal field of view / 2) and the Y coordinate as the coordinate on the straight line Oo in Figure 14A (Px=Ox+Xmax / 2,Py).

[0081] Next, in step S59, it is determined whether the reference position consists of two points. If it is determined that the reference position consists of two points, the process proceeds to step S60. If it is determined that the reference position consists of one point, the process ends because its coordinates have already been calculated in step S58. Next, in step S60, the X-coordinate of the second point (zoom-in starting position) is calculated as (current position center - horizontal field of view / 2), and the Y-coordinate is calculated as the coordinate on the straight line of line Oo in Figure 14A (Px=Ox-Xmax / 2, Py), and the process ends.

[0082] Next, in step S61, based on the result of the determination in step S52, the zoom position coordinate generation unit 18 sets the top edge of the screen as the reference position. Next, in step S62, the zoom position coordinate generation unit 18 calculates the X coordinate of the first point (zoom-out end position) to be the coordinate on the straight line of Oo in Figure 14A, and the Y coordinate to be the coordinate shown as (current position center - vertical field of view / 2) (Px, Py = Oy - Ymax / 2).

[0083] Next, in step S63, it is determined whether the reference position consists of two points. If it is determined that the reference position consists of two points, the process proceeds to step S64. If it is determined that the reference position consists of one point, the process ends because its coordinates have already been calculated in step S62. Next, in step S64, the X-coordinate of the second point (the starting position for zooming in) is calculated using the coordinates on the straight line of Oo in Figure 14A, and the Y-coordinate is calculated using the coordinates shown as (current position center + vertical field of view / 2), and then (Px, Py = Oy + Ymax / 2) the process ends.

[0084] Next, in step S65, based on the result of the determination in step S52, the zoom position coordinate generation unit 18 sets the bottom edge of the screen as the reference position. Next, in step S66, the zoom position coordinate generation unit 18 calculates the X coordinate of the first point (zoom-out end position) to be the coordinate on the straight line of Oo in Figure 14A, and the Y coordinate to be the coordinate shown as (current position center + vertical field of view / 2) (Px, Py = Oy + Ymax / 2).

[0085] Next, in step S67, it is determined whether the reference position consists of two points. If it is determined that the reference position consists of two points, the process proceeds to step S68. If it is determined that the reference position consists of one point, the process ends because its coordinates have already been calculated in step S66. Next, in step S68, the X-coordinate of the second point (zoom-in starting position) is calculated using the coordinates on the straight line of Oo in Figure 14A, and the Y-coordinate is calculated using the coordinates shown as (current position center - vertical field of view / 2), and then (Px, Py = Oy - Ymax / 2) the process ends.

[0086] <Processing to determine the position at the edge of the screen> Next, the details of the screen edge position determination process in step S14 will be explained using the flowchart in Figure 22 as follows. In other words, as shown in Figure 22, in step S71, the zoom position coordinate generation unit 18 calculates and determines the slope (β) of the straight line connecting the center of the field of view at the current position and the center of the field of view at the target position.

[0087] Next, in step S72, the zoom position coordinate generation unit 18 determines the position of the target position (left or right). If it is determined that the target position is to the right of the current position, the process proceeds to step S73; if it is determined that it is to the left, the process proceeds to step S74. Next, in step S73, the zoom position coordinate generation unit 18 determines that the target position is to the right of the current position.

[0088] Next, in step S74, the zoom position coordinate generation unit 18 determines that the target position is to the left of the current position. Next, in step S75, the zoom position coordinate generation unit 18 determines the position of the target position (up and down). If it is determined that the target position is above the current position, the process proceeds to step S76; if it is determined that the target position is below the current position, the process proceeds to step S77.

[0089] Next, in step S76, the zoom position coordinate generation unit 18 determines that the target position is above the current position. Next, in step S77, the zoom position coordinate generation unit 18 determines that the target position is below the current position. Next, in step S78, the zoom position coordinate generation unit 18 determines whether the target position is above the current position. If it is determined that the target position is above the current position, the process proceeds to step S79; if it is determined that the target position is not above the current position, the process proceeds to step S86.

[0090] Next, in step S79, since it was determined in step S78 that the target position is above the current position, it is now determined whether or not it is to the right. If it is determined that the target position is to the right of the current position, the process proceeds to step S80; if it is determined that it is not to the right, the process proceeds to step S83. Next, in step S80, since it was determined in steps S78 and S79 that the target position is above and to the right of the current position, the zoom position coordinate generation unit 18 compares the slope of the diagonal of the field of view of the current position (α) with the slope of the line connecting the centers of the field of view of the current position and the field of view of the target position (β) to determine whether the relationship α > β is satisfied. If the relationship is satisfied, the process proceeds to step S81; otherwise, the process proceeds to step S82.

[0091] Next, in step S81, since it was determined in step S80 that the relationship α > β is satisfied, the zoom position coordinate generation unit 18 sets the left end as the reference point and terminates the process. On the other hand, in step S82, since it was determined in step S80 that the relationship α > β is not satisfied, the zoom position coordinate generation unit 18 sets the lower end as the reference and terminates the process.

[0092] Furthermore, in step S83, since it was determined in steps S78 and S79 that the target position is above the current position and not to the right, the zoom position coordinate generation unit 18 compares the slope of the diagonal of the field of view of the current position (α) with the slope of the line connecting the centers of the field of view of the current position and the field of view of the target position (β) to determine whether the relationship -α>β is satisfied. If the relationship is satisfied, the process proceeds to step S84; otherwise, the process proceeds to step S85.

[0093] Next, in step S84, since it was determined in step S83 that the relationship -α>β is satisfied, the zoom position coordinate generation unit 18 sets the rightmost edge as the reference point and terminates the process. On the other hand, in step S85, since it was determined in step S83 that the relationship -α>β is not satisfied, the zoom position coordinate generation unit 18 sets the lower end as the reference and terminates the process.

[0094] Furthermore, in step S86, since it was determined in step S78 that the target position is not above the current position, the zoom position coordinate generation unit 18 now determines whether it is to the right or not. If it is determined that the target position is to the right of the current position, the process proceeds to step S87; if it is determined that it is not to the right, the process proceeds to step S90. Next, in step S87, the slope of the diagonal of the field of view at the current position (-α) is compared with the slope of the line connecting the centers of the field of view at the current position and the field of view at the target position (β) to determine whether the relationship -α > β is satisfied. If the relationship is satisfied, the process proceeds to step S88; otherwise, the process proceeds to step S89.

[0095] Next, in step S88, since it was determined in step S87 that the relationship -α>β is satisfied, the zoom position coordinate generation unit 18 sets the left edge as the reference point and terminates the process. On the other hand, in step S89, since it was determined in step S87 that the relationship -α>β is not satisfied, the zoom position coordinate generation unit 18 sets the upper end as the reference and terminates the process.

[0096] Furthermore, in step S90, since it was determined in steps S78 and S86 that the target position is neither above nor to the right of the current position, the zoom position coordinate generation unit 18 compares the slope of the diagonal of the field of view of the current position (α) with the slope of the line connecting the centers of the field of view of the current position and the field of view of the target position (β) to determine whether the relationship α > β is satisfied. If the relationship is satisfied, the process proceeds to step S91; otherwise, the process proceeds to step S92.

[0097] Next, in step S91, since it was determined in step S90 that the relationship α > β is satisfied, the zoom position coordinate generation unit 18 sets the rightmost edge as the reference point and terminates the process. On the other hand, in step S92, since it was determined in step S90 that the relationship α > β is not satisfied, the zoom position coordinate generation unit 18 sets the upper end as the reference and terminates the process.

[0098] <Key Features> As shown in Figure 2, the imaging device 10 of this embodiment includes a lens unit LU, pan / tilt direction drive mechanisms 15a and 15b, a lens drive unit 13, a velocity waveform generation unit 19, and a pan / tilt speed correction calculation unit 20. The lens unit LU includes a plurality of lenses having optical axes. The pan / tilt direction drive mechanisms 15a and 15b adjust the orientation of the lens unit LU in the pan / tilt direction. The lens drive unit 13 adjusts the shooting range including the subject by changing the relative positions of the plurality of lenses included in the lens unit LU. The velocity waveform generation unit 19 generates a velocity waveform that shows the drive speed synchronized between the pan / tilt direction and the zoom position based on the amount of movement (distance) between the current position and the target position when moving from the field of view at the current position to the field of view at the target position. The pan / tilt speed correction calculation unit 20 corrects the velocity waveform in the pan / tilt direction with respect to the velocity waveform generated by the velocity waveform generation unit 19 according to the change in focal length (zoom magnification) over time.

[0099] This allows for the correction of a trapezoidal velocity waveform that synchronizes zoom and pan / tilt drive, for example, when moving from the current position to the target position while zooming in, so that the drive speed in the pan / tilt direction decreases as the zoom magnification increases. Conversely, when moving from the current position to the target position while zooming out, the trapezoidal velocity waveform can be corrected by synchronizing the zoom and pan / tilt drive so that the drive speed in the pan / tilt direction increases as the zoom magnification decreases.

[0100] Therefore, even when automatic shooting is performed using the imaging device 10, natural-looking images can be captured, just as when a cameraman (person) is taking the pictures. As a result, when shooting a subject while controlling at least one of the panning and tilting movements while zooming in / out, it is possible to capture smooth, natural-looking footage.

[0101] [Other embodiments] Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the gist of the disclosure. (A) In the above embodiments, the imaging device 10 and its control method were described using examples that implement the present disclosure. However, the present disclosure is not limited thereto.

[0102] For example, this disclosure may be implemented as a control program that causes a computer to execute the control method of the imaging device described above. This control program is stored in the memory (storage unit) installed in the imaging device. The CPU reads the control program stored in memory and instructs the hardware to execute each step. More specifically, the same effect as described above can be obtained by the CPU reading the control program and executing the steps described above.

[0103] Furthermore, this disclosure may be implemented as a recording medium that stores a control program that causes a computer to execute a control method for an imaging device. (B) In the above embodiment, an example was described in which the imaging device 10 includes a pan-direction drive mechanism 15a and a tilt-direction drive mechanism 15b that drive in the pan direction and tilt direction, respectively, and corrects the velocity waveforms in both the pan and tilt directions according to the change in focal length over time. However, this disclosure is not limited thereto.

[0104] For example, if the imaging device of this disclosure is configured to have a drive mechanism that is driven in only one of the pan or tilt directions, then the velocity waveform in at least one of the pan and tilt directions should be corrected according to the change in focal length over time. (C) In the above embodiment, an example was described in which the imaging device 10 is equipped with a rotation mechanism 11a that drives in the roll direction around the roll axis X. However, this disclosure is not limited thereto.

[0105] For example, the imaging device of this disclosure may have a configuration that does not have a roll drive mechanism in the roll direction. (D) In the above embodiment, an example was given in which the velocity waveform generation unit 19 generates a trapezoidal velocity waveform by synchronizing the driving of the pan-direction drive mechanism 15a, the tilt-direction drive mechanism 15b, and the lens drive unit 13 from the current position to the target position. However, this disclosure is not limited thereto.

[0106] For example, the velocity waveform generation unit may be configured to generate velocity waveforms other than trapezoidal, such as a rectangular velocity waveform. (E) In the above embodiment, an example was given in which preset control is performed so that the field of view becomes a pre-registered one when a predetermined operation input (for example, a predetermined button operation) is made as the shooting range moves from the current position to the target position. However, this disclosure is not limited to this.

[0107] For example, instead of using preset control, the system may be configured to control the field of view of the target position when moving from the current position to the target position, based on a manually entered target position. (F) In the above embodiment, an example was given in which, in constant screen change rate control, the drive speed in the pan / tilt direction is controlled while zooming out from the current position, and the drive speed in the pan / tilt direction is controlled while zooming in toward the target position. However, this disclosure is not limited to this.

[0108] For example, in the constant screen change rate control described above, the drive speed in the pan / tilt direction may be controlled while zooming in from the current position, and the drive speed in the pan / tilt direction may be controlled while zooming out toward the target position. (G) In this embodiment, as shown in Figure 7, an example was given in which, when shooting while zooming in from a subject, the velocity waveforms of the pan / tilt direction drive mechanisms 15a and 15b are generated in synchronization with the zoom, and are corrected to be larger in the initial stage when the zoom magnification is low. However, the present invention is not limited to this.

[0109] For example, conversely to Figure 7, when shooting while zooming out from the subject, a configuration may be used to generate a speed waveform of the pan / tilt direction drive mechanism (see, for example, Figure 16A) that is synchronized with the zoom and corrected to become larger in the final stage when the zoom magnification is low. <Note> Based on the above description of embodiments, the following technologies are disclosed.

[0110] (Technology 1) The imaging device relating to Technology 1 is A lens unit including multiple lenses having an optical axis, A posture adjustment mechanism for adjusting the orientation of the lens unit in at least one of the pan and tilt directions, A zoom mechanism that adjusts the shooting range including the subject by changing the relative positions of the plurality of lenses included in the lens unit, A speed waveform generation unit generates a speed waveform that indicates a drive speed synchronized with the zoom position and at least one of the pan and tilt directions, based on the amount of movement between the current position and the target position when moving from the current field of view to the target position. A control unit that corrects at least one of the velocity waveforms in the pan direction and tilt direction with respect to the velocity waveform generated in the velocity waveform generation unit, in accordance with the change in focal length over time, It is equipped with.

[0111] (Technology 2) The imaging device relating to Technology 2 is the imaging device relating to Technology 1, The control unit corrects the velocity waveform in at least one of the pan direction and the tilt direction in accordance with the change in focal length over time so that the rate of change of the screen remains constant.

[0112] (Technology 3) The imaging device relating to Technology 3 is the imaging device relating to Technology 2, The control unit corrects the speed waveform by multiplying the speed waveform in at least one of the pan and tilt directions by a speed multiplier in at least one of the pan and tilt directions, which is calculated so that the rate of change of the screen remains constant with respect to the change in focal length.

[0113] (Technology 4) The imaging device relating to Technology 4 is an imaging device relating to any one of Technology 1 to 3, The control unit integrates the corrected velocity waveform to calculate the arrival position in at least one of the pan direction and the tilt direction, and corrects the velocity waveform using the ratio of the distance to the arrival position to the distance to the target position.

[0114] (Technology 5) The imaging device relating to Technology 5 is an imaging device relating to any one of Technologies 1 to 4, At least one of the pan direction and the tilt direction and the zoom position at the target position are set in advance. The control unit controls the movement from the current field of view to the target position in response to a predetermined operation input.

[0115] (Technology 6) The imaging device relating to Technology 6 is an imaging device relating to any one of Technology 1 to 5, The system further includes a field of view range determination unit that determines whether the field of view of the target position is within the range of the field of view of the current position. The control unit corrects the velocity waveform in accordance with the change in focal length when the field of view of the target position is within the range of the field of view of the current position.

[0116] (Technology 7) The imaging device relating to Technology 7 is an imaging device relating to any one of Technology 1 to 6, The velocity waveform generation unit generates a trapezoidal velocity waveform. (Technology 8) The imaging device relating to Technology 8 is an imaging device relating to any one of Technology 1 to 7, The system further includes an image sensor that converts light incident from the subject side through the aforementioned lens unit into an electrical signal and outputs image data.

[0117] (Technology 9) The imaging device relating to Technology 9 is an imaging device relating to any one of Technology 1 to 8, The control unit controls the zoom mechanism to zoom out when moving to a target position outside the current field of view so that the entire area including the current position and the target position is visible, and the velocity waveform generation unit generates a velocity waveform that includes a first control section in which the operation of the attitude adjustment mechanism and the zoom operation of the zoom mechanism are synchronized according to the positional relationship between the current position and the target position, and a second control section in which the zoom operation of the zoom mechanism is not performed, but at least one of the pan direction and tilt direction of the attitude adjustment mechanism is operated.

[0118] (Technology 10) The imaging device relating to Technology 10 is the imaging device relating to Technology 9, When the control unit moves to a target position that is within the current field of view, it controls the zoom mechanism to zoom out so that the entire area including the current position and the target position is visible, and the velocity waveform generation unit generates a velocity waveform that includes a first control section that synchronizes the operation of the attitude adjustment mechanism and the zoom operation of the zoom mechanism according to the positional relationship between the current position and the target position.

[0119] (Technology 11) The imaging device relating to Technology 11 is an imaging device relating to Technology 9 or 10, The control unit determines that the target position is outside the current field of view if the amount of movement between the first end of the current field of view and the second end of the target position opposite the first end is greater than the field of view at the wide end of the zoom mechanism.

[0120] (Technology 12) The imaging device relating to technology 12 is an imaging device relating to any one of technologies 9 to 11, The control unit determines which of the four areas, obtained by dividing the rectangle of the field of view of the current position by diagonals, the target position is located on. (Technology 13) The imaging device relating to Technology 13 is the imaging device relating to Technology 12, When the control unit determines that the target position is located on the side of one of the four areas, it sets a reference position that will be the edge of the screen when zooming out, depending on whether the slope of the line connecting the center of the current position and the center of the target position is on the upper or lower side of the slope of the diagonal.

[0121] (Technology 14) The imaging device relating to Technology 14 is the imaging device relating to Technology 11, If the target position is outside the current field of view, the control unit calculates a first center position at the wide end of the wide end that zooms out from the current position and a second center position at the wide end that zooms in towards the target position.

[0122] (Technology 15) The imaging device relating to Technology 15 is the imaging device relating to Technology 14, The control unit moves from the current position to the target position, with the first center position being the end position for zooming out from the current position and the second center position being the start position for zooming in to the target position.

[0123] (Technology 16) The imaging device relating to Technology 16 is the imaging device relating to Technology 15, The speed waveform generation unit generates a first speed waveform that includes the drive speed in at least one of the pan direction and the tilt direction from the current position to the zoom-out end position, and the drive speed of the zoom mechanism.

[0124] (Technology 17) The imaging device relating to Technology 17 is the imaging device relating to Technology 16, The speed waveform generation unit generates a second speed waveform that includes the drive speed in at least one of the pan direction and the tilt direction from the zoom-in start position to the target position, and the drive speed of the zoom mechanism.

[0125] (Technology 18) The imaging device relating to Technology 18 is the imaging device relating to Technology 17, The speed waveform generation unit generates a third speed waveform that includes the drive speed in at least one of the pan direction and the tilt direction from the zoom-out end position to the zoom-in start position, and the drive speed of the zoom mechanism.

[0126] (Technology 19) The imaging device relating to Technology 19 is the imaging device relating to Technology 18, The control unit generates a composite velocity waveform by connecting the first velocity waveform and the third velocity waveform at the connection point between the first velocity waveform and the third velocity waveform, such that the area of ​​the acceleration portion of the third velocity waveform is added to the area of ​​the deceleration portion of the first velocity waveform.

[0127] (Technology 20) The imaging device relating to Technology 20 is the imaging device relating to Technology 19, The control unit generates a composite velocity waveform by connecting the third velocity waveform and the second velocity waveform at the connection point between the third velocity waveform and the second velocity waveform, such that the area of ​​the deceleration portion of the second velocity waveform is added to the area of ​​the acceleration portion of the third velocity waveform.

[0128] (Technology A) The imaging device related to Technology A is A lens unit including multiple lenses having an optical axis, A posture adjustment mechanism for adjusting the orientation of the lens unit in at least one of the pan and tilt directions, A zoom mechanism that adjusts the shooting range including the subject by changing the relative positions of the plurality of lenses included in the lens unit, A speed waveform generation unit generates a speed waveform that, when moving from the current field of view to the target position, generates a speed waveform that shows a drive speed synchronized with at least one of the pan direction and tilt direction and the zoom position based on the amount of movement between the current position and the target position, and when moving to the target position which is outside the range of the current field of view, controls the zoom mechanism to zoom out so that the entire area including the current position and the target position is shown, and generates a speed waveform that includes a first control section in which the operation of the attitude adjustment mechanism and the zoom operation of the zoom mechanism are synchronized according to the positional relationship between the current position and the target position, and a second control section in which the zoom operation of the zoom mechanism is not performed and at least one of the pan direction and tilt direction of the attitude adjustment mechanism is operated, It is equipped with.

[0129] (Technology B) The imaging device related to Technology B is A lens unit including multiple lenses having an optical axis, A posture adjustment mechanism for adjusting the orientation of the lens unit in at least one of the pan and tilt directions, A zoom mechanism that adjusts the shooting range including the subject by changing the relative positions of the plurality of lenses included in the lens unit, A speed waveform generation unit generates a speed waveform that indicates a drive speed synchronized with at least one of the pan and tilt directions and the zoom position based on the amount of movement between the current position and the target position when moving from the current field of view to the target position, and controls the zoom mechanism to zoom out when moving to the target position which is within the range of the current field of view so that the entire area including the current position and the target position is visible, and generates a speed waveform that includes a first control section that synchronizes the operation of the attitude adjustment mechanism and the zoom operation of the zoom mechanism according to the positional relationship between the current position and the target position. It is equipped with. [Industrial applicability]

[0130] The imaging device of this disclosure has the effect of capturing smooth, natural-looking images when photographing a subject while controlling at least one of panning and tilting movements while zooming in / out, and is therefore widely applicable to various imaging devices that perform zoom photography. [Explanation of Symbols]

[0131] 10 Imaging device 10a Base section 10b Swivel section 11 Camera head 11a Rotation mechanism 12 Image sensor 13. Lens drive unit (zoom mechanism) 14. Lens Control Unit (Control Unit) 15a Pan direction drive mechanism (attitude adjustment mechanism) 15b Tilt direction drive mechanism (attitude adjustment mechanism) 16 Pan / Tilt Direction Control Unit 17. Field of View Range Determination Unit (Control Unit) 18 Zoom position coordinate generation unit 19 Speed ​​waveform generator 20. Pan / Tilt Speed ​​Correction Calculation Unit (Control Unit) 21 Position Correction Speed ​​Calculation Unit (Control Unit) L focal length LU Lens Unit X-roll axis

Claims

1. A lens unit including multiple lenses having an optical axis, A posture adjustment mechanism for adjusting the orientation of the lens unit in at least one of the pan and tilt directions, A zoom mechanism that adjusts the shooting range including the subject by changing the relative positions of the plurality of lenses included in the lens unit, A speed waveform generation unit generates a speed waveform that indicates a drive speed synchronized with the zoom position and at least one of the pan and tilt directions, based on the amount of movement between the current position and the target position when moving from the current field of view to the target position. A control unit that corrects at least one of the velocity waveforms in the pan direction and tilt direction with respect to the velocity waveform generated in the velocity waveform generation unit, in accordance with the change in focal length over time, An imaging device equipped with the following features.

2. The control unit corrects the velocity waveform in at least one of the pan direction and the tilt direction so that the rate of change of the screen remains constant, in accordance with the change in focal length over time. The imaging apparatus according to claim 1.

3. The control unit corrects the speed waveform by multiplying the speed waveform in at least one of the pan and tilt directions by a speed multiplier calculated so that the rate of change of the screen remains constant with respect to the change in focal length. The imaging apparatus according to claim 2.

4. The control unit integrates the corrected velocity waveform to calculate the arrival position in at least one of the pan and tilt directions, and corrects the velocity waveform using the ratio of the distance to the arrival position to the distance to the target position. The imaging apparatus according to claim 1 or 2.

5. At least one of the pan and tilt directions and the zoom position at the target position are set in advance. The control unit controls the movement from the current field of view to the target position in response to a predetermined operation input. The imaging apparatus according to claim 1 or 2.

6. The system further includes a field of view range determination unit that determines whether the field of view of the target position is within the range of the field of view of the current position, The control unit corrects the velocity waveform in accordance with the change in focal length when the field of view of the target position is within the range of the field of view of the current position. The imaging apparatus according to claim 1 or 2.

7. The velocity waveform generation unit generates a trapezoidal velocity waveform. The imaging apparatus according to claim 1 or 2.

8. The system further includes an image sensor that converts light incident from the subject side through the lens unit into an electrical signal and outputs image data. The imaging apparatus according to claim 1 or 2.

9. The control unit controls the zoom mechanism to zoom out when moving to a target position outside the current field of view so that the entire area including the current position and the target position is visible, and the velocity waveform generation unit generates a velocity waveform that includes a first control section in which the operation of the attitude adjustment mechanism and the zoom operation of the zoom mechanism are synchronized according to the positional relationship between the current position and the target position, and a second control section in which the zoom operation of the zoom mechanism is not performed, but at least one of the pan direction and tilt direction of the attitude adjustment mechanism is operated. The imaging apparatus according to claim 1.

10. The control unit controls the zoom mechanism to zoom out when moving to a target position within the current field of view so that the entire area including the current position and the target position is visible, and the velocity waveform generation unit generates a velocity waveform that includes a first control section that synchronizes the operation of the attitude adjustment mechanism and the zoom operation of the zoom mechanism according to the positional relationship between the current position and the target position. The imaging apparatus according to claim 1.

11. The control unit determines that the target position is outside the current field of view if the distance between the first end of the current field of view and the second end of the target position opposite the first end is greater than the field of view at the wide end of the zoom mechanism. The imaging device according to claim 9.

12. The control unit determines which of the four areas, obtained by dividing the rectangle of the field of view of the current position by diagonals, the target position is located on. The imaging device according to claim 9.

13. When the control unit determines that the target position is located on the side of one of the four areas, it sets a reference position that will be the edge of the screen when zooming out, depending on whether the slope of the line connecting the center of the current position and the center of the target position is on the upper or lower side of the slope of the diagonal. The imaging apparatus according to claim 12.

14. If the target position is outside the current field of view, the control unit calculates a first center position at the wide end of the zoom range from the current position and a second center position at the wide end of the zoom range towards the target position. The imaging apparatus according to claim 11.

15. The control unit sets the first center position as the zoom-out end position from the current position and the second center position as the zoom-in start position to the target position, and moves from the current position to the target position. The imaging apparatus according to claim 14.

16. The speed waveform generation unit generates a first speed waveform that includes the drive speed in at least one of the pan direction and the tilt direction from the current position to the zoom-out end position, and the drive speed of the zoom mechanism. The imaging apparatus according to claim 15.

17. The speed waveform generation unit generates a second speed waveform that includes the drive speed in at least one of the pan direction and the tilt direction from the zoom-in start position to the target position and the drive speed of the zoom mechanism. The imaging device according to claim 16.

18. The speed waveform generation unit generates a third speed waveform that includes the drive speed in at least one of the pan direction and the tilt direction from the zoom-out end position to the zoom-in start position, and the drive speed of the zoom mechanism. The imaging apparatus according to claim 17.

19. The control unit generates a composite velocity waveform by connecting the first velocity waveform and the third velocity waveform at the connection point between the first velocity waveform and the third velocity waveform, such that the area of ​​the acceleration portion of the third velocity waveform is added to the area of ​​the deceleration portion of the first velocity waveform. The imaging apparatus according to claim 18.

20. The control unit generates a composite velocity waveform by connecting the third velocity waveform and the second velocity waveform at the connection point between the third velocity waveform and the second velocity waveform, such that the area of ​​the deceleration portion of the second velocity waveform is added to the area of ​​the acceleration portion of the third velocity waveform. The imaging device according to claim 19.

21. A control method for an imaging device comprising: a lens unit including a plurality of lenses having an optical axis; an attitude adjustment mechanism for adjusting the orientation of the lens unit in at least one of the pan direction and the tilt direction; and a zoom mechanism for adjusting the shooting range including a subject by changing the relative positions of the plurality of lenses included in the lens unit, A speed waveform generation step generates a speed waveform that indicates a drive speed synchronized with the zoom position and at least one of the pan direction and tilt direction, based on the amount of movement between the current position and the target position when moving from the current field of view to the target position. A control step in which, with respect to the velocity waveform generated in the velocity waveform generation step, at least one of the velocity waveforms in the pan direction and tilt direction is corrected according to the change in focal length over time, A control method for an imaging device equipped with the following features.

22. A control program for an imaging device comprising: a lens unit including a plurality of lenses having an optical axis; an attitude adjustment mechanism for adjusting the orientation of the lens unit in at least one of the pan and tilt directions; and a zoom mechanism for adjusting the shooting range including a subject by changing the relative positions of the plurality of lenses included in the lens unit, A speed waveform generation step generates a speed waveform that indicates a drive speed synchronized with the zoom position and at least one of the pan direction and tilt direction, based on the amount of movement between the current position and the target position when moving from the current field of view to the target position. A control step in which, with respect to the velocity waveform generated in the velocity waveform generation step, at least one of the velocity waveforms in the pan direction and tilt direction is corrected according to the change in focal length over time, A control program that causes a computer to execute a control method for an imaging device equipped with such a device.

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