JP3466782B2 - Remote monitoring system, remote control device and remote monitoring method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is a remote monitoring system, a method remote control device and remote monitoring, in particular remote monitoring system using a communication path of the low-bandwidth video transmission, a method for remote control devices and remote monitoring.

[0002]

2. Description of the Related Art A remote control system for remotely operating a video camera equipped with an electric pan head has been put into practical use as a remote monitoring system. FIG. 5 shows an example of an operation screen in a conventional remote monitoring system. An image from a video camera placed at a remote place is displayed in the image window 110. By operating various buttons on the camera operation window 112 displayed adjacent to the video window 110 with a pointing device such as a mouse, it is possible to freely change the direction and shooting magnification of the camera at a remote location.

In such a remote monitoring system, it is common to use a transmission line having a sufficient bandwidth for transmitting a captured image.

[0004]

However, for the purpose of cost reduction and the like, there is a desire to use a transmission line having a relatively narrow bandwidth such as an analog public line.
Further, considering the use of a computer network, it is often impossible to secure a sufficient transmission capacity for transmitting a video signal in baseband. When the transmission capacity cannot be secured, a method of reducing the frame rate (the number of frames per unit time) is often adopted as a kind of information compression.

A normal moving image is 30 frames / second,
When the frame rate decreases, for example, while viewing the transmitted video, rotate the camera at a remote location (for example,
When panning, the camera often rotates too much, and it is difficult to remotely control the camera so as to face the target object.

The difficulty of such remote operation is the same for tilt and zoom.

It is an object of the present invention to solve the above problems and provide a remote monitoring system , a remote operating device and a remote monitoring method that enable appropriate remote operation regardless of the transmission rate.

Another object of the present invention is to provide a remote monitoring system , a remote control device, and a remote monitoring method that can accurately remotely control a camera even when a transmission line having a low transmission rate is used.

[0009]

The remote monitoring system according to the present invention.
The stem consists of an imaging device whose shooting conditions can be controlled externally,
Display means for displaying a captured image of an imaging device and the imaging device
A remote control device having operating means for remotely controlling the device
Remote monitoring system consisting of
A rate monitor that monitors the image transmission rate to the remote control device.
The visual means and the image transmission detected by the rate monitoring means.
Depending on the sending rate, the imaging device by the remote control device
Equipped with response control means for controlling the response speed of the rotary operation of the device.
However, the response restricting means converts the captured image of one screen into the image.
Above the transmission time required to transmit based on the transmission rate
Based on the response speed of the rotation operation
The change time required to change the shooting direction of the camera is more
Regulate the response speed of the above rotation operation so that it does not become small.
By doing so, the screen before and after the above rotation operation is made continuous
It is characterized by The remote monitoring system according to the present invention,
An imaging device that allows external control of shooting conditions, and the imaging device
The display means for displaying the captured image and the image pickup device are remotely controlled.
Remote consisting of a remote control device equipped with operating means
A monitoring system, the remote operation from the imaging device
Rate monitoring means for monitoring the image transmission rate to the device,
The image transmission rate detected by the rate monitoring means and
Depending on the angle of view based on the zoom amount of the imaging device,
The response speed of the rotation operation of the image pickup device by the remote control device.
It is characterized by comprising a response restricting means for restricting.
The remote monitoring method according to the present invention allows external control of shooting conditions.
Display the captured image of a different imaging device on the remote control device.
And a remote monitoring method that remotely controls the imaging device.
Image transmission from the imaging device to the remote control device.
A rate monitoring process for monitoring the transfer rate and the rate monitoring
Depending on the image transmission rate detected in the process,
Response speed of rotation operation of the imaging device by the remote operation device
And a response regulation process that regulates
Is a one-screen captured image transmitted at the above image transmission rate.
From the transmission time required to send, the response speed of the above rotation operation
Based on the above, change the shooting direction of the camera by the width of the above-mentioned shot image
Do not make the change time required to do so smaller
By regulating the response speed of the above-mentioned rotation operation,
The feature is that the screens before and after the work are made continuous in a plane. Book
The remote monitoring method according to the invention allows external control of shooting conditions.
Display the image taken by the imaging device on the remote control device
Together with a remote monitoring method for remotely operating the imaging device.
Therefore, image transmission from the imaging device to the remote control device
A rate monitoring process for monitoring rates and the rate monitoring process
Image transmission rate detected in
Depending on the angle of view based on the zoom amount, the remote control device
Response regulation that regulates the response speed of the rotation operation of the image pickup device
A control process is provided. Remote according to the invention
The operation device is a remote operation included in the remote monitoring system described above.
It is a device.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a schematic block diagram of an embodiment of the present invention. The camera 10 has a structure in which the image pickup unit 12 is mounted on an electric pan head 14 that can pan and tilt the direction of the image pickup unit 12 by an external control signal. Imaging unit 12
Includes a zoom drive circuit 12a that changes the photographing magnification according to an external control signal, and the electric pan head 14 includes a rotation drive circuit 14a that rotates the imaging unit 12 up and down and left and right according to an external control signal. The video signal captured by the image capturing unit 12 of the camera 10 is supplied to the image transmitting apparatus 20 via the video cable 16. Further, a control signal for controlling the zoom and the shooting direction of the camera 10 is transmitted from the image transmission circuit 20 to the camera 10 via the control signal line 18.

The image transmission device 20 includes an A / D converter 22 for converting an analog video signal from the camera 10 into a digital signal, and a CPU 2 for controlling the entire image transmission device 20.
4. Connected to the image receiving device 40 via the communication line 60, transmitting captured image information to the image receiving device 40, and controlling the camera 10 (including control of the platform 14; hereinafter,
the same. (2) A zoom amount control interface 2 for generating a control signal for designating a zoom position of the camera 10 and a communication circuit 26 for exchanging information on the image receiving device 40 and supplying the information to the drive circuit 12a via the control signal line 18.
8 and a platform control interface 30 that generates a control signal for designating the rotation direction of the platform 14 and supplies the control signal to the rotation drive circuit 14a via the control signal line 18.

Further, the image receiving device 40 includes a CPU 42 for controlling the entire image receiving device 40, a storage circuit 44 for storing various fluctuation data, and a communication circuit 2 of the image transmitting device 20.
The communication circuit 46 that communicates image information and camera control information with the image display device 6 and the image transmitted from the image transmission device 20 are displayed on a monitor 70 (hereinafter abbreviated as monitor) 70 in a predetermined area. And a coordinate pointing device interface 50 to which a mouse 80 as a pointing device is connected. With the mouse 80, the camera operation panel displayed on the screen of the monitor 70 is operated.

The monitor 70 is composed of a CRT display or a liquid crystal display, and a video window 72 for displaying a photographed image and a camera operation window 74 for operating the camera are displayed.

A coordinate input device such as a digitizer tablet may be used in place of or in addition to the mouse 80. As an alternative to mouse 80, track balls are well known.

Next, the operation of this embodiment will be described. As the operation description, only the case of pan for changing the shooting direction to the left and right will be described, but when changing the shooting direction to up and down (tilt),
The same applies to zoom and focus control. Needless to say, the CPU 24 of the image transmitting device 20 and the C of the image receiving device 40 determine and execute the following steps.
The PU 42 is exclusively in charge.

FIG. 2 shows a flowchart of an operation example of the image receiving apparatus 40 of this embodiment. The procedure shown in FIG. 2 is activated by powering on, forcible resetting, or an explicit initialization instruction from the user.

First, the time tf required to transmit one frame of an image is calculated (S1). Information on the line rate and the image size is required to obtain tf.
Since the user has previously selected a communication line such as PSTN or ISDN from the menu or the like and selected the image size,
Divert those information. For example, assuming that the line rate of the communication line 60 is x, and the image data amount of one frame (which is also the amount of transmission data here because information is not compressed) is y, the time required to transmit an image of one frame. t
f becomes tf = y / x.

Next, the time tθ required to change the photographing direction by the width W of the image is calculated from the angle of view and the current swinging speed (panning speed) (S2). Since the angle of view θ is a function of the zoom amount z as is well known, the angle of view θ can be determined from the current zoom amount z. The angle of view θ can be expressed as the angle of view θ (z) as a function of the zoom amount z. The current swing speed is v. The angle of view θ (z) and the current swing speed v are
It can be acquired from 0 through the image transmission device 20 and the communication line 60. The time tθ required to change the shooting direction of the camera 10 by the width W of the image is tθ = θ (z) / v.

It is determined whether tf≤tθ (S3), and t
If f> tθ, the swing speed v is adjusted so that tf ≦ tθ, and the resulting swing speed v is transmitted from the image receiving device 40 to the image transmitting device 20 via the communication line 60. Then, the image transmission device 20 sets a new swing speed v in the rotation drive circuit 14a of the platform 14 via the platform control interface 30 (S4). Subsequent swinging motion depends on the swinging speed v set here. tf ≦ t
If θ (S3), the current swing speed v is maintained.

By controlling the swinging speed at S1 to S4, the image is transmitted from the image transmitting device 20 to the image receiving device 40 by 1
While the frame is being transmitted, the camera platform 12 is so large that the platform 14 may not know the shooting position of the next frame.
It will not rotate.

Next, the image receiving device 40 is connected to the image transmitting device 2.
In response to this command, the image transmission device 20 transmits the image from the camera 10 from the communication circuit 26 to the image reception device 40 via the communication line 60 in response to the command. The image receiving device 40 receives the image from the communication line 60 by the communication circuit 46 and applies it to the monitor 70 via the display interface 48. Images captured by the camera 10 are continuously transmitted from the image transmitting device 20 to the image receiving device 40. As a result, the captured image of the camera 10 is displayed as a moving image in the video window 72 of the monitor 70 (S5).

The user can instruct the camera control window 74 to rotate in the shooting direction with the mouse 80 (S).
6). Upon receiving the instruction, the image receiving apparatus 40 requests the image transmitting apparatus 20 to suspend image transmission and sends a camera control signal corresponding to the user's instruction to the camera control window 74 to the communication circuit 46 and the communication line 60. It is transmitted to the image transmitting device 20 via the. The image transmission device 20
A control signal for directing in the direction designated by the camera control command is applied to the rotation drive circuit 14a of the platform 14 via the platform control interface 30. As a result, the rotation drive circuit 14a causes the imaging unit 10 to operate at a predetermined swing speed (if changed in S4, the changed swing speed).
Is rotated to face the shooting direction designated by the user through the camera control window 74 (S7).

When the image pickup unit 12 faces in the direction designated by the user, the image receiving device 40 requests the image transmitting device 20 to restart the image transmission. After that, the image taken in that direction is transmitted from the image transmitting device 20 to the image receiving device 40, and is displayed in the video window 72 of the monitor 70.

In FIG. 2, the image transmission from the image transmission device 20 to the image reception device 40 is temporarily interrupted each time the camera is operated, but an image during rotation of the camera 10 may be transmitted. The good news is clear.

FIG. 3 is an operation flowchart of the image transmitting apparatus 20. This procedure is performed by the CP in the image transmission device 20.
It is executed by U24.

It waits for a command to be received from the image receiving device 40 (S11). When you receive a command,
It is determined which of the shooting direction instruction command, the zoom amount change instruction command, the image shooting command, and the swinging speed notification command, and the processing corresponding to each is executed.

That is, if the command is a photographing direction instruction command (S
12), the platform 14 via the platform control interface 30.
The rotation direction data of absolute designation or relative designation is applied to the rotation drive circuit 14a to change the photographing direction (S13).

If the command is a zoom amount change instruction command (S14), absolute or relative zoom amount data is applied to the zoom drive circuit 12a via the zoom amount control interface 28 to change the zoom amount 8S1.
5).

If the command is an image capture command (S1
6), the output image of the camera 10 is taken into the image transmitting device 20 by the A / D converter 22, and transmitted from the communication circuit 26 to the image receiving device 40 via the communication line 60 (S1).
7).

If the command is a swinging speed notification command (S
18), the rotation speed is notified to the rotation drive circuit 14a via the platform control interface 30 and set (S1).
9).

There are other commands for starting and stopping the image transmission. In response to these commands, the image transmitting device 20 starts and stops the image transmission to the image receiving device 40.

Since the amount of data of the moving picture information is enormous, it is normally usual to compress the information before transmission. For that purpose, as shown in FIG. 4, the communication line image transmitting device 20 is provided with an image compressing device 32 for compressing the image captured by the camera 10, and the image receiving device 40 is provided with the image compressing device 32.
The image decompression device 52 for decompressing the compression by the above may be provided. The image captured by the camera 10 is digitized by the A / D converter 22, information-compressed by the image compression device 32, and sent from the communication circuit 26 to the communication line 60.
Further, in the image receiving device 40, the compressed image information from the communication line 60 is applied from the communication circuit 46 to the image decompressing device 52. The image decompression device 52 restores the compressed image information and applies it to the display interface 48.

By adding the image compression on the image transmitting side and the image decompressing on the image receiving side, tf obtained in S1
Need to be changed as follows. That is, when the time required for image compression by the image compression device 32 is tc and the compression rate is α, tf to be obtained in S1 is tf = tc + αy / x.

Further, assuming that the time required for the expansion processing of the image expansion device 52 is td, tθ to be obtained in S2 is tθ = td + θ (z) / v.

Except for modifying tf and tθ in this way,
It can be exactly the same as in FIG.

Although the image receiving apparatus 40 is provided with the response restricting means for restricting the responsiveness of the camera control according to the image transmission rate, the response restricting means may be provided on the image transmitting apparatus 20 side. The good news is clear.

Although only the case of the rotating operation has been described,
Similarly, regarding the change of the zoom position, it is apparent that the response regulation that makes the change speed of the zoom position slower is beneficial as the transmission rate is smaller. In addition to these, the same applies to the control of the focal point.

[0039]

As can be easily understood from the above description, according to the present invention, when a communication channel having a relatively narrow bandwidth is used, the camera can be remotely operated at a response speed corresponding to the frame rate. It becomes possible to operate, and it becomes possible to operate to the target state promptly.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of an embodiment of the present invention.

FIG. 2 is an operation flowchart of the image receiving device 40.

FIG. 3 is an operation flowchart of the image transmission device 20.

FIG. 4 is a schematic configuration block diagram of a modified embodiment.

FIG. 5 is a configuration example of a display screen of a conventional remote monitoring system.

[Explanation of symbols]

10: Camera 12: Imaging unit 12a: Zoom drive circuit 14: Electric platform 14a: rotation drive circuit 16: Video cable 18: Control signal line 20: Image transmission device 22: A / D converter 24: CPU 26: Communication circuit 28: Zoom amount control interface 30: Head control interface 32: Image compression device 40: Image receiving device 42: CPU 44: Memory circuit 46: Communication circuit 48: Display interface 50: Coordinate pointing device interface 52: Image decompression device 60: Communication line 70: Monitor / display device 72: Video window 74: Camera operation window 80: Mouse 110: Video window 112: Camera operation window

Claims (11)

(57) [Claims] 1. An imaging device capable of externally controlling photographing conditions,
Display means for displaying a captured image of the imaging device and the imaging device
Remote control device including operating means for remotely controlling the image device
A remote monitoring system consisting of Image transmission rate from the imaging device to the remote control device
Rate monitoring means for monitoring The image transmission rate detected by the rate monitoring means
According to the remote control device,Rotary operation
ProductResponse control means to control the response speed ofHave, The response restricting means transfers the captured image of one screen to the image transmission.
From the transmission time required to transmit based on the rate,
Based on the response speed of rolling
The change time required to change the shooting direction of is smaller
The response speed of the above rotation operation is regulated so that
And make the screen before and after the rotation operation continuous thing
Remote monitoring system characterized by. 2. The remote monitoring system according to claim 1, wherein the rate monitoring means and the response regulation means are provided in the image pickup device. 3. The remote monitoring system according to claim 1, wherein the rate monitoring means and the response regulation means are provided in the remote operation device. 4. The image pickup apparatus comprises information compression means for compressing information of a photographed image, and the remote control device comprises information decompression means for decompressing image information compressed by the information compression means. 4. The remote monitoring system according to any one of 1 to 3. 5. The remote monitoring according to claim 1, wherein the rate monitoring unit detects a time required to transmit the image information for one screen compressed by the information compression unit. system. Wherein said imaging condition, remote monitoring system according to any one of claims 1 to 5 comprising the imaging magnification of the imaging apparatus. 7. The imaging condition, remote monitoring system according to any one of claims 1 to 6 including the in-focus distance of the imaging device. 8. An imaging device capable of externally controlling photographing conditions,
Display means for displaying a captured image of the imaging device and the imaging device
Remote control device including operating means for remotely controlling the image device
A remote monitoring system consisting of Image transmission rate from the imaging device to the remote control device
Rate monitoring means for monitoring The image transmission rate detected by the rate monitoring means and
Depending on the angle of view based on the zoom amount of the imaging device,
The response speed of the rotation operation of the image pickup device by the remote control device.
And a response control means for controlling Distant
Remote monitoring system. 9.Shooting with an imaging device that allows external control of shooting conditions
Display the shadow image on the remote control device and
A remote monitoring method for remotely operating an imaging device, comprising: Image transmission rate from the imaging device to the remote control device
A rate monitoring step for monitoring Image transmission rate detected in the rate monitoring process
Depending on the rotation of the imaging device by the remote control device
It has a response regulation process that regulates the response speed of the operation, In the response regulation process, the captured image of one screen is transmitted as the image transmission.
From the transmission time required to transmit based on the rate,
Based on the response speed of rolling
The change time required to change the shooting direction of is smaller
The response speed of the above rotation operation is regulated so that
And to make the screen before and after the above rotation operation continuous.
Remote monitoring method characterized by. 10.Of an image pickup device that allows external control of shooting conditions
While displaying the captured image on the remote control device,
A remote monitoring method for remotely operating the imaging device, comprising: Image transmission rate from the imaging device to the remote control device
A rate monitoring step for monitoring Image transmission rate detected in the rate monitoring process
And the angle of view based on the zoom amount of the imaging device
Response speed of rotation operation of the imaging device by the remote operation device
Response regulation process to regulate Distant, characterized by having and
Remote monitoring method. 11. The method according to any one of claims 1 to 8.
A remote control device included in the remote monitoring system according to the item.