JP6626669B2 - Camera control system and camera control method - Google Patents

Description

  The present invention relates to a camera control system and a camera control method, and in particular, is suitable for detecting an object using a laser sensor and measuring a distance, and tracking an object with high accuracy by a monitoring camera to capture an image. The present invention relates to a camera control system and a camera control method.

  Conventionally, surveillance camera systems have been actively used for security, disaster prevention, recording, and the like. In a surveillance camera system, an object is photographed by a video camera, and the image data is stored in a remote storage device such as a hard disk drive (HDD) via a network, and can be monitored from a monitor.

  By the way, in a surveillance camera system, when a surveillance target is used over a wide area and is used for the purpose of crime prevention, traffic monitoring, or the like, control for grasping and tracking the target is required. Here, the target of shooting by the surveillance camera system is a suspicious individual in the case of crime prevention, and a vehicle in traffic monitoring.

  On the other hand, there is a laser radar system as a system for detecting a moving object and performing distance measurement. A laser radar system is a remote sensing technology that uses light to measure the scattered light from a laser beam emitted in a pulsed manner using a laser sensor to analyze the distance to a distant target and the properties of the target. Is what you do.

  Utilizing such features, a camera control system has been proposed in which an object is grasped by a laser radar and a surveillance camera is tracked by the laser radar. For example, in the “security system” described in Patent Literature 1, the position of an intruder is calculated based on distance data and angle data from a sensor unit, and the turning camera unit of the electric turntable is turned based on the position data. Is displayed on a monitor.

JP-A-10-241062

  According to the technique described in Patent Document 1 of the related art described above, the direction of the camera can be controlled. However, since telephoto is not performed, there is a problem that the target image is reduced depending on the distance. Further, in measurement using a general laser sensor, there is a problem that the control / turning speed of the camera is slower than the detection speed of the laser sensor, and tracking is delayed.

  The present invention has been made in order to solve the above-described problems, and an object thereof is to detect an object and measure a distance using a laser sensor, and to track an object captured by the laser sensor with high speed and high accuracy. An object of the present invention is to provide a camera control system capable of taking an image.

  A camera control system according to the present invention is a camera control system in which a laser sensor, a camera, and a control device are respectively connected, a position of an object is detected by a laser sensor, and an image of the object is captured by the camera, and the camera control system is provided for a predetermined time. A target detection unit that detects the position of the target object, a position information measurement unit that measures the position information of the target object, and the angle of view and magnification of the target object taken by the camera are calculated. And a camera operation instructing unit that controls pan / tilt control and zoom magnification of the camera. Then, when the object exceeds a camera control line drawn at a predetermined rate from the end of the angle of view, pan / tilt control is performed on the camera so that the object is at the center of the angle of view. When the difference between the stored past magnification of the target object and the current magnification is equal to or more than a predetermined difference, the zoom magnification is controlled so that the camera has the current magnification.

  Preferably, the position information measurement unit predicts the position of the target object after a predetermined time has elapsed from the past motion vector of the target object, and obtains the position of the target object.

Further, the position information measuring unit holds the time t _{PT at} which the camera performs pan / tilt by a unit angle and the initial movement time T _PT for performing pan / tilt of the camera, and performs the A-degree pan / tilt. Then, the position of the target object is determined in consideration of the time of A · t _PT + T _PT .

  According to the present invention, there is provided a camera control system capable of detecting an object by a laser sensor and measuring a distance, and tracking an object captured by the laser sensor with high speed and high accuracy to capture an image. be able to.

FIG. 1 is an overall configuration diagram of a camera control system according to a first embodiment. FIG. 2 is a functional configuration diagram of the camera control system according to the first embodiment. It is a model figure when grasping an object of a camera control system concerning a first embodiment. It is a block diagram of a camera. 5 is a flowchart illustrating an operation of the camera control system according to the first embodiment. FIG. 4 is a diagram illustrating a relationship between a camera control parameter and a position of an object. FIG. 3 is a diagram illustrating an angle of view and a camera control line. It is a figure showing camera specification information data. It is a figure showing camera measurement information data. It is a figure showing camera control information data. It is a figure explaining position calculation for prediction control. FIG. 3 is a diagram illustrating predictive control of a camera control system.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

[Embodiment 1]
Hereinafter, a camera control system according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 8C.

  First, the configuration and principle of a camera control system according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall configuration diagram of a camera control system according to the first embodiment. FIG. 2 is a functional configuration diagram of the camera control system according to the first embodiment. FIG. 3 is a model diagram of the camera control system according to the first embodiment when grasping an object. FIG. 4 is a configuration diagram of the camera.

  As shown in FIG. 1, the camera control system according to the first embodiment of the present invention includes a laser sensor 100, a control device 200, and a camera 300, which are connected by a network.

  The laser sensor 100 is a device that irradiates light emitted by a semiconductor laser, receives the reflected light, and measures the presence and the distance of the object 10.

  The camera 300 is a device that obtains an image of the object 10 in the target area 110 by rotating the lens of the camera or adjusting the magnification of photographing by a zoom function based on a command from the control device 200.

  The control device 200 is a device that specifies the position of the object 10 based on the measurement data of the laser sensor 100 and controls the camera 300 based on the position. The control device 200 may be realized by installing necessary software on a general personal computer (PC: Personal Computer), or dedicated hardware may be prepared.

  In the example shown in FIG. 1, the control device 200, the laser sensor 100, and the camera 300 are connected via a network, but may be connected via a serial interface such as RS232C or USB.

  The control device 200 has a form in which a CPU (Central Processing Unit) 202, a memory 204, a network I / F 206, a display I / F 208, an input / output I / F 210, and an auxiliary storage I / F 212 are connected by a bus.

  The CPU 202 controls each unit of the control device 200, loads necessary programs to the main storage device 204, and executes them.

  The memory 204 is generally constituted by a volatile memory such as a RAM, and stores a program executed by the CPU 202 and data to be referred to.

  The network I / F 206 is an interface for connecting to a network.

  The display I / F 208 is an interface for connecting a display device 220 such as an LCD (Liquid Crystal Display).

  The input / output I / F 210 is an interface for connecting an input / output device. In the example of FIG. 1, a keyboard 230 and a mouse 232 as a pointing device are connected.

  The auxiliary storage I / F 212 is an interface for connecting an auxiliary storage device such as a hard disk drive (HDD) 250 or a solid state drive (SSD).

  The HDD 250 has a large storage capacity, and stores a program for executing the present embodiment. In the control device 200, a sensor control program 700, a detection / ranging program 702, an area determination program 704, a camera control program 706, and a camera driver 708 are installed.

  The sensor control program 700 is a program for controlling the laser sensor 100. The detection / ranging program 702 is a program for detecting the object 10 by the laser sensor 100 and measuring the distance. The area determination program 704 is a program for determining whether or not the target object 10 obtained based on the measurement result of the laser sensor 100 is included in the target area 110 of the camera 300. The camera control program 706 is a program for controlling the camera based on the measurement result of the laser sensor 100. The camera I / F program 708 is a program that performs interface processing of the connected camera 300, and differences in the communication method, command, and sequence of the camera 300 of each company are adjusted in this part.

  The HDD 250 stores image data 720 photographed by the camera program, and is referred to as necessary for monitoring.

  Next, a functional configuration of the camera control system according to the first embodiment will be described with reference to FIG.

  As shown in FIG. 2, the camera control system according to the present embodiment includes a sensor control unit 402, an object detection unit 404, a position information measurement unit 406, an area determination unit 408, a camera control unit 410, and a camera I / F unit 420. Each function is provided.

  The sensor control unit 402 is a part that controls the laser sensor 100. The target detection unit 404 is a part that detects a target based on a measurement result from the laser sensor 100. The position information measurement unit 406 is a unit that measures a distance to an object based on a measurement result from the laser sensor 100 and detects the position. The area determination unit 408 is a part that determines whether the target object 10 is included in the area of the camera 300. The camera control unit 410 is a unit that controls the camera based on the measurement result of the laser sensor 100, and includes functional units of a camera view angle / magnification determination unit 412 and a camera operation instruction unit 414. The camera angle of view / magnification determination unit 412 is a part that calculates the angle of view and the magnification of the camera of the target object based on the measurement result of the laser sensor 100 and the internal control data. The camera operation instructing unit 414 is a unit that gives an operation instruction of the camera based on the calculation result in the camera angle of view / magnification determining unit 412. The camera I / F program 708 is a part for interfacing the connected camera 300, and the difference in the communication method, command, and sequence of the camera 300 of each company is intended to be adjusted in this part.

  FIG. 3 is a plan view of an image when grasping an object in the camera control system according to the present embodiment. The position (x, y, z) of the object 10 is grasped by the laser sensor 100, and when the object 10 is located in the object area 110, the object 300 is photographed by the camera 300. The angle of view at this time is α (described later).

Next, the configuration of the camera will be described with reference to FIG.
The camera 300 includes a command I / F unit 50, a motor control unit 52, a zoom control unit 54, a pan direction motor 56, a tilt direction motor 58, a pan direction head 60, a tilt direction head 62, and a camera lens unit 64. ing.

  The camera 300 receives a command from the outside at the command I / F unit 50, and transfers it to the motor control unit 52 and the zoom control unit 54. The motor control unit 52 rotates the pan direction motor 56 in accordance with the instruction of the command, and rotates the camera lens unit 68 by rotating the pan direction pan head 60 by the designated angle (pan direction: lateral direction). Similarly, the tilt direction motor 58 is rotated, and the tilt direction pan head 62 is rotated by the designated angle (tilt direction: vertical direction) to rotate the camera lens unit 68.

  Next, the operation of the camera control system according to the first embodiment will be described with reference to FIGS. 5 to 8C. FIG. 5 is a flowchart illustrating the operation of the camera control system according to the first embodiment. FIG. 6 is a view for explaining the relationship between the control parameters of the camera and the position of the object. FIG. 7 is a diagram illustrating an angle of view and a camera control line. FIG. 8A is a diagram showing camera specification information data. FIG. 8B is a diagram showing camera measurement information data. FIG. 8C is a diagram showing camera control information data.

  First, the camera control system periodically captures the object 10 by the laser sensor 100 and obtains a measurement result (S10). Here, the periodic time is a time preset in the system, for example, 250 [ms]. This time may be changed by an administrator.

Next, the position of the object is calculated (S12). If the coordinates of the object 10 are (x, y, z), the coordinates of the camera 300 are (X, Y, Z), and the distance of the object from the camera is R (# 801 in FIG. 8B), R (≧ 0) Is represented by the following (Equation 1).
R ² = (xx) ² + (y−Y) ² + (z−Z) ² (formula 1)

  Next, it is determined whether or not the target object 10 is in the target area 110 for camera shooting (S14). When the target object 10 is in the target area 110 for camera shooting (S14: YES), the process proceeds to the next S16. On the other hand, when the target object 10 is not in the target area 110 for camera shooting (S14: NO), the process returns to S10.

  Next, the angle of view W (# 802 in FIG. 8B) is calculated (S16).

The angle-of-view width W is represented by the following (Equation 2).
W = 2R · tan (α / 2) (Equation 2)
Here, α is the angle of view (# 905 in FIG. 8C), and R is the distance from the already-existing camera 300 to the object 10.

  When the angle of view W is determined, the position of the camera control line 70 is determined. As shown in FIG. 7, the position of the camera control line 70 is a position that is left and right W · γ away from the end of the angle of view width. Here, γ is the range ratio of the camera control line (# 903 in FIG. 8C).

  Then, it is determined whether or not the object 10 has exceeded the range of the camera control line 70 (S18). When the object 10 has exceeded the range of the camera control line 70 (S18: YES), the camera 300 is panned. Perform tilt control to instruct the camera to move by giving parameters of the horizontal angle and the vertical angle so that the object 10 is at the center of the angle of view (S20, CASE1 in FIG. 6).

Next, magnification calculation is performed for zoom control (S22).
The magnification z (# 803 in FIG. 8B) is represented by the following (Equation 3).
_{z = I w / (2f w} tan (α / 2)) = I w R / f w W ... ( Equation 3)
Here, _{I w} is the width of the image sensor (♯701 in FIG. 8A), _{f w} is a focal length (W end) (♯703 in Figure 8A).

  Then, it is determined whether or not the magnification z of the object 10 exceeds a specified range (S24). When the magnification z exceeds the specified range (S24: YES), zoom control is performed on the camera 300. Then, the camera is controlled so as to achieve the zoom of the magnification z (S26, CASE2 in FIG. 6).

Here, as when the magnification z is out of the range prescribed, it is when the magnification z and the difference between the past magnification (absolute value of the difference) is equal to or greater than the magnification limits delta _{z (♯904} in FIG. 8C) Is defined.

  As described above, in the camera control system according to the present embodiment, the camera is not controlled at any time based on the position information detected in the cycle of the laser sensor. It is controlled to face the subject.

  Conventionally, when camera control is performed at the cycle of the laser sensor and an object is tracked and photographed, the camera control speed is slower, and the accumulation and delay of control commands and the processing load increase. . In the camera control system according to the present embodiment, such a situation can be prevented, and the object can be accurately tracked at an appropriate timing to photograph the object with less image blur.

[Embodiment 2]
Hereinafter, a camera control system according to the second embodiment of the present invention will be described with reference to FIG.
FIG. 9 is a diagram illustrating position calculation for predictive control.

In the present embodiment, when detecting the position of the target object 10, the movement of the target object is predicted to determine the position. That is, in the position information calculation process of S14 in FIG. 5 of the first embodiment, as shown in FIG. 9, the position at the time of elapse of t _f (♯906 in FIG. 8C) is determined from the past movement vector of the target object. calculate.

  Thereby, it is possible to perform control for more accurately tracking and photographing the moving object 10.

[Embodiment 3]
Hereinafter, a camera control system according to a third embodiment of the present invention will be described with reference to FIG. FIG. 10 is a diagram illustrating predictive control of the camera control system.

As it is shown in the second embodiment, with respect to the object 10 at the time lapse t _f, and running the pan and tilt control of the zoom. Here, the target position 601 in FIG. 10 is a target 10 of camera control instruction, the target position 602 and the position at the time lapse _{t f} (FIG. 10 (a)). However, when pan / tilt and zoom control is performed on the camera, the speed from the command to the completion of turning differs depending on the performance of the camera. As a result, when the camera has completed turning and turned to the target position 602, the target object 10 may be further ahead by the time required for controlling the camera. Therefore, in the present embodiment, the target position is calculated in consideration of the camera control time.

It takes t _PT (# 901 in FIG. 8C) for the pan / tilt control of rotating the camera of the camera 100 once, and it takes T _PT (# 902 in FIG. 8C) as the initial movement time of the pan / tilt control. I do. At this time, assuming that the pan / tilt of the A degree is performed, the time required is A · t _PT + T _PT .

Therefore, in the present embodiment, the predicted position is calculated as the target position 602 at the time of elapse of t _{f and} the predicted vector at the time of E · t _PT + T _PT elapse as the coping position 603 of the object 10.

  Therefore, according to the camera control of the present embodiment, more accurate prediction can be performed in consideration of the pan / tilt control of the camera 300, and the object can be tracked with high accuracy and photographed by the camera 300. become.

10 target object, 100 laser sensor, 110 target area, 200 control device, 300 camera
202 CPU (Central Processing Unit), 204 memory, 206 network I / F, 208 display I / F, 210 input / output I / F, 212 auxiliary storage I / F, 220 display device, 230 Keyboard, 232 mouse, 250 HDD (Hard Disk Drive),
Reference numeral 402: sensor control unit, 404: target detection unit, 406: position information measurement unit, 408: area determination unit, 410: camera control unit, 420: camera I / F unit.

Claims (6)

A laser control system, wherein a laser sensor, a camera, and a control device are respectively connected, the position of the target is detected by the laser sensor, and the target is photographed by the camera.
An object detection unit that detects the position of the object at regular intervals,
A position information measuring unit that measures position information of the object,
A camera angle-of-view / magnification determining unit that calculates a view angle width and a magnification in shooting of the camera of the target object and determines a trigger of camera control according to a condition .
For the camera, a pan / tilt control and a camera operation instructing unit that controls zoom magnification are provided.
The camera angle-of-view / magnification determining unit calculates the distance between the camera and the object from the position of the object and the installation position of the camera, and calculates the angle of view from the distance between the camera and the object and the angle of view of the camera. Calculate the width,
The camera angle-of-view / magnification determining unit determines whether the object has passed a camera control line drawn at a predetermined rate from an end of the angle-of-view width,
The camera operation instructing unit is configured to pan and move the camera so that the object becomes the center of the angle of view when a camera control line drawn at a predetermined ratio from the end of the angle of view is exceeded. Perform tilt control,
The camera angle-of-view / magnification determining unit calculates a magnification from the distance between the camera and the object, the angle-of-view width, the width of the image sensor of the camera, and the focal length of the camera,
The camera angle-of-view / magnification determining unit determines whether or not the object is a stored past magnification and a current magnification is equal to or greater than a predetermined difference,
The camera operation instructing unit is configured such that when the object has a stored past magnification and a current magnification that is equal to or more than a predetermined difference, the zoom magnification is set so that the object has the current magnification. A camera control system characterized by controlling the camera.   2. The camera control system according to claim 1, wherein the position information measuring unit estimates a position of the target object after a lapse of a predetermined time from a past motion vector of the target object, and obtains the position of the target object. 3. Further, the position information measuring unit holds a time t _{PT at} which the camera performs pan / tilt by a unit angle and an initial movement time T _PT for performing pan / tilt of the camera, and sets the pan / tilt of A degree. 3. The camera control system according to claim 2, wherein the position of the object is obtained by inserting a time corresponding to _AtPT + _TPT . A laser control method of a camera control system, wherein a laser sensor, a camera, and a control device are connected to each other, the position of the target is detected by the laser sensor, and the target is photographed by the camera.
The camera control system includes:
An object detection unit that detects the position of the object at regular intervals,
A position information measuring unit that measures position information of the object,
A camera angle-of-view / magnification determining unit that calculates an angle-of-view width and magnification in shooting of the object camera, and determines a trigger of camera control according to a condition .
For the camera, a pan / tilt control and a camera operation instructing unit that controls zoom magnification are provided.
The camera angle-of-view / magnification determining unit calculates the distance between the camera and the object from the position of the object and the installation position of the camera, and calculates the angle of view from the distance between the camera and the object and the angle of view of the camera. Calculating a width;
The camera angle-of-view / magnification determining unit determines whether or not the object has passed a camera control line drawn at a predetermined ratio from an end of the angle-of-view width,
The camera operation instructing unit is configured so that, when the object exceeds a camera control line drawn at a predetermined ratio from an end of the angle of view, the object is at the center of the angle of view. On the other hand, a step of performing pan / tilt control,
The camera angle of view / magnification determining unit calculates a magnification from the distance between the camera and the object, the angle of view, the width of the image sensor of the camera, and the focal length of the camera,
Wherein the camera angle of view / magnification determining unit determines whether or not the target object has a stored past magnification and a current magnification is equal to or greater than a predetermined difference;
The camera operation instructing unit sets a zoom magnification to the camera so that when the object has a stored past magnification and a current magnification is equal to or greater than a predetermined difference, the camera has a current magnification. Performing a control of the camera.   The camera control method according to claim 4, wherein the position information measurement unit estimates a position of the target object after a lapse of a predetermined time from a past motion vector of the target object, and obtains the position of the target object. Further, the position information measuring unit holds a time t _{PT at} which the camera performs pan / tilt by a unit angle and an initial movement time T _PT for performing pan / tilt of the camera, and sets the pan / tilt of A degree. 6. The camera control method according to claim 5, wherein at the time of performing, the position of the object is obtained by inserting a time of _AttPT + _TPT .

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