JP2002354458A - Remote monitoring system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a remote monitoring system in which the probability of occurring troubles simultaneously on a main transmission line and a spare transmission line is low and high safety is ensured. SOLUTION: Under normal state of an optical fiber cable 21, a monitoring video signal picked up by means of a monitoring camera 11 is converted through an electrical-to-optic converter 14 into an optical signal which is delivered through the optical fiber cable 21 to a monitoring center 30. The monitoring center 30 converts a received optical video signal through an optical-to-electrical converter 31 into an electric signal which is monitored by a monitor terminal 33. When a trouble occurs on the optical fiber cable 21, the monitor terminal 33 detects the abnormality and actuates a dial-up router 36 which is connected with an image server 19 through an ISDN line 23. The image server 19 transmits a monitor video signal encoded by an encoder 18 to the monitoring center 30. The monitoring center 30 receives the monitor video signal from the image server 19 and monitors it at the monitor terminal 33.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote monitoring system in which a specific monitoring area such as a construction site is photographed by a camera, and the video signal is transmitted to a monitoring center or the like via a transmission line to monitor the remote monitoring system.

[0002]

2. Description of the Related Art Conventionally, for example, when monitoring a specific area in a factory or a construction site, a monitoring camera is installed in the monitoring area, and an image captured by the camera is transmitted to a monitoring center via an analog transmission line. A remote monitoring system adapted to monitor is generally used.

In the above-mentioned conventional remote monitoring system, a video signal is generally transmitted through a transmission line of one route. However, if a failure such as a disconnection occurs in the transmission line, the video signal cannot be transmitted. There is. In order to cope with such a case, a system is conceivable in which a backup spare transmission line is provided in addition to the main transmission line, and a video signal is transmitted using the spare transmission line when a failure occurs in the main transmission line. ing.

[0004]

By providing a spare transmission line as described above, even if a failure occurs in the main transmission line, it can be dealt with, and the safety of the system can be improved.

[0005] However, the above-mentioned conventional remote monitoring system includes:
Since the transmission lines of the same transmission format are simply provided in duplicate, there is a high probability that the main transmission line and the backup transmission line are disconnected at the same time. For example, in the case where a main transmission line and a backup transmission line are provided in one optical fiber cable, if the main transmission line is disconnected, there is a high probability that the backup transmission line will be disconnected at the same time, and the security of the system will be greatly improved. Can not do.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a remote monitoring system in which the probability of simultaneous failure of a main transmission line and a backup transmission line is low and high security is obtained. Aim.

[0007]

According to the present invention, a surveillance camera is installed in a surveillance area, and a surveillance video signal photographed by the surveillance camera is transmitted to a surveillance terminal device via a transmission line for remote monitoring. In a surveillance system, a main transmission line for transmitting a surveillance video signal from the surveillance camera to a surveillance terminal device, and transmitting a surveillance video signal from the surveillance camera to the surveillance terminal device when a failure occurs in the main transmission line. A standby transmission line, wherein the main transmission line and the standby transmission line use different transmission schemes. Specifically, an analog transmission line is used as the main transmission line, and a digital line is used as the backup transmission line.

By using different transmission schemes for the main transmission line and the backup transmission line as described above, the probability that the main transmission line and the backup transmission line become abnormal at the same time is extremely low, and very high security is obtained. Can be. In addition, when a digital line is used as a backup transmission line, a failure signal of the surveillance camera can be transmitted to the surveillance terminal together with the surveillance video signal, and the surveillance terminal can grasp the operation state of the surveillance camera. It becomes possible.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a remote monitoring system according to an embodiment of the present invention. In FIG. 1, 1
A monitoring device 0 is provided in a monitoring area such as a construction site, for example, and includes a monitoring camera 11 such as a CCTV (Closed-Circuit Television) camera. The monitoring camera 11 includes a support mechanism 12 having a driving device such as a motor.
The driving device is driven by an external control command, and can be rotated in the left-right direction and the up-down direction.

From the monitoring camera 11, for example, NTS
A video signal of a C (National Television System Committee) system is output. This video signal is split into two by a splitter 13, and one of the split signals is an electrical / optical converter (E /
O) It is input to 14. The electrical / optical converter 14 converts a video signal output from the monitoring camera 11, that is, a moving image analog signal, into a pulse coded modulation (PFM) signal and converts the signal into an optical signal. To the monitoring center 30 via the Internet.

The optical video signal transmitted to the monitoring center 30 is input to an optical / electrical converter (O / E) 31, converted into an electric signal, and returned to an NTSC video signal. The monitoring center 30 includes a plurality of optical / electrical converters 31 for converting each optical video signal transmitted from a plurality of monitoring cameras via a transmission line into an electric signal. The electrical signals converted by the plurality of optical / electrical converters 31, that is, the NTSC video signals are converted into video switches (VSW) 3
2 and input to the monitor terminal 33 for monitoring. As the monitoring terminal device 33, for example, a personal computer is used.

The monitoring terminal device 33 has a function of inputting a command for controlling the monitoring direction to the monitoring camera 11 from a key input device. In this case, the operation of controlling the monitoring direction of the monitoring camera 11 is performed while watching the monitor screen of the monitoring terminal device 33. When a control operation is performed on the monitoring camera 11 in the monitoring terminal device 33, the signal line 34
Is output to the electrical / optical converter 35. The electrical / optical converter 35 converts the camera control command into an optical signal and transmits the optical signal to the monitoring device 10 via the optical fiber cable 22.

The monitoring device 10 receives the camera control command (optical signal) sent from the monitoring center 30 and converts
The signal is converted into an electric signal by 5 and input to the control unit 16. The control unit 16 generates a camera drive signal based on the camera control command, inputs the camera drive signal to the support mechanism 12 via the switch 17, drives the motor, and rotates the monitoring camera 11 in the designated direction. .

The video signal of the surveillance camera 11 distributed by the distributor 13 is, for example, M-JPEG (Motion-Joint Photographic Experts) by the encoder 18.
Group) and MPEG4 (Moving Picture Experts Group)
4), and is input to an image server (WWW (World Wide Web) server) 19. The image server 19 includes the monitoring camera 11.
Input a failure signal or the like. The monitoring camera 11 has a self-diagnosis function, and outputs to the image server 19 a status signal indicating whether it is normal or a failure, a failure signal indicating the content of the failure when a failure occurs, and the like.

The image server 19 is connected to a monitoring center 30 via a digital line, such as an ISDN line 23, which is a backup transmission line. In the monitoring center 30, the ISDN
A dial-up router 36 is provided between the line 23 and the monitoring terminal device 33. The monitoring terminal device 33 is provided with a browser (World Wide Web Browser), and can display an image sent from the image server 19 via the ISDN line 23. Further, the monitoring terminal device 33 has an automatic detection function for detecting whether the video signal is normally transmitted from the monitoring device 10 via the optical fiber cable 21. When an abnormality is detected, such as when the video signal is interrupted, the switch to the dial-up router 36 side is made, and connection with the image server 19 of the monitoring apparatus 10 is made by dial-up.

When the monitoring terminal device 33 is connected to the image server 19 by the dial-up router 36, the monitoring terminal device 33 displays an image sent from the image server 19 on a monitor screen and transmits a camera control command to the image server 19. It has become. When a camera control command is sent from the monitoring terminal device 33, the image server 19 outputs a camera control signal to the support mechanism 12 via the switch 17 based on the command, and controls the direction of the monitoring camera 11. I do. The switch 17 is automatically switched by a signal from the control unit 16 or the image server 19.

In the above configuration, when the optical fiber cable 21 is in a normal state, the monitoring video signal captured by the monitoring camera 11 is converted into an optical signal by the electric / optical converter 14, and the optical fiber which is the main transmission line is used. The data is sent to the monitoring center 30 via the cable 21. The monitoring center 30
The optical video signal sent via the optical fiber cable 21 is converted into an electrical signal by the optical / electrical converter 31, selected by the video switch 32 and input to the monitoring terminal device 33,
Display on the monitor screen and monitor. At this time, when changing the monitoring direction of the monitoring camera 11, the user operates the key input device while watching the monitor screen to adjust the left, right, up and down directions of the monitoring camera 11.

A camera control command is output from the monitoring terminal device 33 to the signal line 34 by the above-described camera direction adjustment operation, converted into an optical signal by the electric / optical converter 35, and then transmitted to the monitoring device via the optical fiber cable 22. Sent to 10. The monitoring device 10 receives the camera control command (optical signal) sent from the monitoring center 30 by the optical / electrical converter 15, converts it into an electric signal, and inputs the electric signal to the control unit 16. The control unit 16 controls the support mechanism 1 based on the camera control command.
2 to rotate the monitoring camera 11 in the designated direction. As described above, the direction of the monitoring camera 11 can be arbitrarily adjusted by operating the keys on the monitoring terminal device 33.

In the above state,
Monitoring device 10 using optical fiber cables 21 and 22
When a failure such as a break in the optical fiber cable 21 occurs while a signal is being transmitted and received between the monitoring center 30 and the monitoring video signal from the monitoring camera 11 is not transmitted to the monitoring center 30, the monitoring is performed. The terminal device 33 automatically detects the state and switches the line to the dial-up router 36 side. That is, when detecting an abnormality in the monitoring video signal, the monitoring terminal device 33 sends a command to the dial-up router 36 and connects to the image server 19 via the ISDN line 23 by dial-up.

When the image server 19 is connected to the monitoring center 30 by the dial-up router 36, the image server 19 transmits the monitoring video signal encoded and compressed by the encoder 18 and the failure signal of the monitoring camera 11 via the ISDN line 23. To the monitoring center 30. The monitoring center 30
The monitoring video signal sent by the ISDN line 23 is received by the monitoring terminal device 33 via the dial-up router 36 and displayed on the monitor screen. At this time, if it is necessary to adjust the monitoring direction of the monitoring camera 11, the monitoring direction can be arbitrarily adjusted in the same manner as when signals are transmitted and received through the optical fiber cables 21 and 22.

When a line having a transmission system different from that of the main transmission line is used as a spare transmission line as described above, the probability that the main transmission line and the spare transmission line become abnormal at the same time is extremely low, and very high security is obtained. Can be.

When a digital line is used as a transmission line, a failure signal and the like of the monitoring camera 11 can be transmitted to the monitoring center 30 together with a monitoring video signal. Can be grasped.

In the above-described embodiment, when a failure such as disconnection occurs in the optical fiber cable 21, the monitoring terminal device 33 automatically detects the state and switches the line to the dial-up router 36 side. However, it goes without saying that the line may be manually switched.

Further, in the above embodiment, the case where the optical fiber cable is used as the analog transmission line has been described. However, the present invention can be implemented in the same manner as the above embodiment using a metal cable.

[0025]

As described above in detail, according to the present invention, a surveillance camera is installed in a surveillance area, and a surveillance video signal photographed by the surveillance camera is transmitted to a surveillance terminal device via a transmission line. In a remote monitoring system for remote monitoring,
A spare transmission line is provided as the transmission line in addition to the main transmission line, and different transmission methods are used for the main transmission line and the spare transmission line. Very low and very high security can be obtained. In addition, by using a digital line as a backup transmission line, a failure signal of the surveillance camera and the like can be transmitted to the surveillance terminal device together with the surveillance video signal, and the surveillance terminal device grasps the operation state of the surveillance camera. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a remote monitoring system according to an embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 monitoring device 11 monitoring camera 12 support mechanism 13 distributor 14 electric / optical converter 15 optical / electric converter 16 control unit 17 switch 18 encoder 19 image server 21, 22 optical fiber cable 23 ISDN line 30 monitoring center 31 light / Electric converter 32 Video switch 33 Monitoring terminal device 34 Signal line 35 Electric / optical converter 36 Dial-up router

Claims (6)

[Claims] 1. A remote monitoring system in which a monitoring camera is installed in a monitoring area and a monitoring video signal captured by the monitoring camera is transmitted to a monitoring terminal device via a transmission line to remotely monitor the monitoring camera. A main transmission line for transmitting a monitoring video signal to a monitoring terminal device, and a spare transmission line for transmitting a monitoring video signal from the monitoring camera to the monitoring terminal device when a failure occurs in the main transmission line, A remote monitoring system characterized in that different transmission systems are used for the main transmission line and the backup transmission line. 2. The remote monitoring system according to claim 1, wherein said main transmission line uses an analog transmission line, and said spare transmission line uses a digital line. 3. A surveillance camera installed in a surveillance area,
A distributor that distributes the monitoring video signal output from the monitoring camera into two parts, an analog transmission line that transmits one of the monitoring video signals distributed by the distributor to the monitoring terminal device, and the distributor that distributes the monitoring video signal. An encoder for encoding the other surveillance video signal, an image server for distributing the surveillance video signal encoded by the encoder to the surveillance terminal device, and transmitting the surveillance video signal distributed by the image server to the surveillance terminal device And a connection means provided on the monitoring terminal device side and connecting the monitoring terminal device to the image server via the digital line when a failure occurs in the analog transmission line. And remote monitoring system. 4. A surveillance camera installed in a surveillance area,
A distributor that divides a monitoring video signal output from the monitoring camera into two, an electrical / optical converter that converts one of the monitoring video signals distributed by the distributor into an optical signal, and the electrical / optical converter An optical fiber cable for transmitting the optical signal converted by the optical fiber cable, an optical / electrical converter for converting the optical signal transmitted by the optical fiber cable into an electric signal, and an electric signal converted by the optical / electrical converter A monitoring terminal device for displaying on a monitor screen, an encoder for encoding the other monitoring video signal distributed by the distributor, an image server for delivering the encoded monitoring video signal to the monitoring terminal device, and the image A digital line for transmitting a monitoring video signal delivered by a server to the monitoring terminal device,
A remote monitoring system provided on the monitoring terminal device side, the connection device connecting the monitoring terminal device to an image server via the digital line when a failure occurs in the analog transmission line. , 5. The remote monitoring system according to claim 3, wherein the image server distributes a failure signal of the monitoring camera to the monitoring terminal device together with the monitoring video signal encoded by the encoder. 6. A control means for supporting a monitoring camera by a rotatable support mechanism and controlling a monitoring direction of the monitoring camera by a camera control signal sent from a monitoring terminal device. The remote monitoring system according to any one of claims 1 to 5, wherein