JPH0993567A - Video monitor system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain radio transmission with ease of system installation works at a low work cost. SOLUTION: The system is made up of a camera 21 picking up an image of an object to be monitored, a modulation section 22 modulating a video signal outputted from the camera 21 with spread spectrum using a pseudo noise code, a radio transmission section 23 converting the modulation signal into a required radio frequency, amplifying power and sending a radio wave from an antenna 27, a radio reception section 24 receiving the transmission radio wave, amplifying the signal at a low noise, converting the signal frequency into a required frequency, a demodulation section 25 demodulating the spread spectrum signal using the same pseudo noise code as that for the modulation section 22, a monitor 26 displaying the monitored image based on the demodulated video signal and a transmission or reception antenna 27.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video surveillance system having a surveillance camera and a video monitor for displaying a surveillance image as a basic configuration.

[0002]

2. Description of the Related Art Conventionally, CCTV (closed circuit television) is used in large-scale facilities such as steel mills and chemical plants.
2. Description of the Related Art An image monitoring system has been adopted in which a plurality of objects to be monitored are photographed by different cameras, and the images are displayed at a remote place, for example, in a central monitoring room or the like, and intensively and efficiently monitored.

FIG. 4 is a block diagram of an embodiment of a conventional video surveillance system. Reference numerals 44 and 45 are a first fixed camera and a second fixed camera for photographing the monitored object at a preset fixed angle of view. 47 and 50 are a first video monitor and a second video monitor for displaying the supplied image. Reference numeral 33 is for selecting an image (input) of the first fixed camera and the second fixed camera 44, 45 and the like, and freely switching and displaying the monitoring image on a monitor (output) of the second video monitor 50 and the like. It is a video switching device. The above is the basic configuration of the video surveillance system. Reference numeral 41 is a human detection unit configured by an infrared sensor or the like, and 42 is an intrusion detection unit configured by a magnetic switch or the like installed at an opening / closing location such as a door or a window. 43
Is a swivel camera unit having a structure in which a camera having a zoom function and the like is housed in a camera case installed on the swivel device. Reference numeral 46 denotes a microphone / amplifier section including a microphone and an amplifier for amplifying the output of the microphone.

Reference numeral 31 denotes the video switching unit 33 and the like, and RS-
It is a main controller connected to the bus by a 485 serial interface. Reference numeral 32 denotes a detection input / control device that connects the human detection unit 41 and the intrusion detection unit 42, receives a detection signal, and outputs a required operation signal to each corresponding unit. Reference numeral 34 is a character superimposing device that superimposes a desired character on the supplied video signal and outputs it. Reference numeral 35 is a voice switching device which, when a plurality of microphone / amplifier units 46 are connected, selects an input, freely switches and outputs it. Reference numeral 48 denotes a first operation unit for giving a selection instruction to the image switching unit 33 to select an image to be recorded in the image recording unit 49 and performing various operations such as recording and other operations of the system. 49 is
For example, it is an image recording unit composed of time lapse video or the like. Reference numeral 51 is a second operation unit that performs the same operation as the first operation unit 48, such as giving an instruction to the video switching unit 33 in order to select a video to be displayed on the second video monitor 50. Reference numeral 52 denotes an amplifier / speaker unit that amplifies and outputs the sound transmitted via the sound switching device 35.

The monitoring operation of the above-described conventional video monitoring system will be described. First, an operation example of the basic configuration system will be described. For example, the first fixed camera 44 that shoots the monitored object at a fixed angle of view is circuit-connected to the first video monitor 47 that displays the supplied image via the video switching unit 33. In addition, the second fixed camera 45 is circuit-connected to the second video monitor 50. Therefore, the image captured by the first fixed camera 44 is displayed on the first video monitor 47, and the image captured by the second fixed camera 45 is displayed on the second video monitor 50.

Next, a monitoring operation example will be described for a large-scale system in which other constituent elements are connected. For example, the human detection unit 4
1 or when the intrusion detection unit 42 detects an abnormality and transmits an abnormality signal to the detection input / control device 32, the detection input / control device 32 causes the main control device 31 to indicate the abnormality via a bus of RS-485. The main control device 31 transfers a required instruction to the detection input / control device 32 while transferring the signal. As a result, the detection input / control device 32 gives an instruction to record the monitor image from the first fixed camera 44, which is monitoring the corresponding portion, in the image recording unit 49, and
It is displayed on the first video monitor 47.

In another case, when the main control unit 31 determines that the abnormal place is within the photographing range of the swivel type camera unit 43 based on the transmitted abnormal signal, the main control unit 31 passes through the detection input / control unit 32. Then, the swivel camera unit 43 is controlled as required. For example, the main control device 31 detects and inputs the sensor so that the installation position of the sensor that has transmitted the abnormal signal is the center of the angle of view among the installed detection sensors.
Instruction is given to the swivel camera unit 43 via the control device 32. At the same time, the zoom function of the camera of the swivel camera unit 43 is operated so as to obtain a predetermined angle of view. The obtained image is recorded in the image recording section 49 and displayed on the first video monitor 47, for example. At this time, the observer confirms the image on the monitor and performs a required operation from the first operation unit 48, and the main control device 31 and the detection input / control device 32 are operated.
Via, the swivel camera unit 43 is instructed to obtain a desired angle of view and zoom angle of view.

Further, the main control unit 31 instructs the video switching unit 33 and the character superimposing unit 34 via a bus to take a picture of the location where the abnormality occurs.
3 through the character superimposing device 34, for example,
The camera number is superimposed on the image and output. In addition, the monitoring operation other than the above is appropriately performed by an automatic instruction of the main control device 31 or an instruction of the first operation unit 48 or the second operation unit 51 by a supervisor. For example, in order to confirm whether the operation sound of the plant is normal, the microphone of the microphone / amplifier unit 46 is installed at a required position, and the speaker of the amplifier / speaker unit 52 in the monitoring room monitors the abnormal sound.

However, since the above-mentioned respective parts and devices are all wire-connected by electric wires, the facility construction of the system is not easy, and especially in the building after construction where the system is not assumed, the facility construction is difficult. There was a problem that the cost increased.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide an image monitoring system in which facility construction of the system is easy and construction cost is low.

[0011]

In order to achieve the above object, in a video surveillance system comprising a camera section and a display section for displaying a photographed image from the camera section, an image of the camera section is displayed on the display section. A transmission device for wireless transmission is provided.

In another configuration, the camera section, the display section for displaying the image taken by the camera section, the main control unit for controlling each section of the system, the detection signal are input, and the required control signal is output. A detection control device, a video switching device that selects an image signal transmission path between the camera unit and the display unit, a character superimposing device that superimposes characters on a captured image of the camera unit, and a transmission path of an input voice. In a video monitoring system including a voice switching device, the main control device, the detection control device, the video switching device, the character superimposing device, and the voice switching device are mutually connected by a wireless transmission path.

[0013]

[Operation] With the above configuration, in the first configuration,
Since the video signal transmission between the camera section and the display section is wireless, the electric wires required for image transmission etc. are not required. Further, in the other configuration, since the mutual transmission of the video signal and the control signal between the respective devices below the main control device is performed by the wireless system, the electric wire for connecting the devices is unnecessary.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A video surveillance system according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram of an embodiment of a video surveillance system according to the present invention. Reference numeral 21 is a camera for photographing the monitored object. Reference numeral 22 denotes a modulator that modulates the video signal output by the camera 21 by, for example, spread spectrum using a pseudo noise code. Reference numeral 23 is a wireless transmission unit that converts the modulated signal into a required wireless frequency, amplifies the power, and transmits it by radio waves from the antenna 27. The above is the video monitoring system on the camera side. Reference numeral 24 is a wireless reception unit that receives a transmission radio wave, amplifies it with low noise, and converts it into a required frequency. A demodulation unit 25 demodulates spread spectrum using the same pseudo noise code as the modulation unit 22. A monitor 26 displays a monitor image based on the demodulated video signal. 27 is a transmitting or receiving antenna. The above is the video monitoring system on the monitor side.

FIG. 2 is a block diagram of a second embodiment of the video surveillance system according to the present invention. Reference numeral 1 denotes a main control unit 11 that controls each unit of the system, an SS modulation / demodulation unit 12 that performs spread spectrum modulation and spread spectrum demodulation on a signal transmitted and received by the main control unit 11, and a modulated signal at a required radio frequency. The main control device is composed of a transmitter / receiver 13 that converts the power into a radio wave, power-amplifies it, and transmits it as a radio wave from the antenna 14, receives the transmitted radio wave, amplifies it with low noise, and converts it into a required frequency. The SS modulation / demodulation unit 12
And a portion configured by the transmitting / receiving unit 13 will be referred to as a wireless transmission device hereinafter.

Reference numeral 2 is a detection control device composed of a detection control unit 15 which inputs a detection signal and outputs a required control signal, and the wireless transmission device. Reference numeral 3 denotes a video switching device including a video switching unit 16 that selects an image signal transmission path between the camera unit and the display unit, and the wireless transmission device. Reference numeral 4 is a character superimposing unit 1 that superimposes a desired character on the image captured by the camera
7 and the wireless transmission device. Reference numeral 5 is a voice switching unit 1 for selecting a transmission path of input voice.
8 and the wireless transmission device.

The wireless transmission operation of the video surveillance system according to the present invention will be described with reference to FIGS. In the example of FIG.
The modulation unit 22 converts the video signal of the monitored object captured by the camera 21.
Then, for example, a modulated signal is obtained by spread spectrum or the like using a pseudo noise code, and the wireless transmitter 23 sends the modulated signal to a required wireless frequency, for example, a carrier frequency (2.4).
The frequency is converted into the GHz band, etc.), the power is amplified, and the electric wave is transmitted from the antenna 27. The radio receiver 24 receives the transmitted radio wave, amplifies it with low noise, and converts it into a required frequency.
The demodulation unit 25 demodulates the spread spectrum signal using the same pseudo noise code as the modulation unit 22 to obtain a video signal. The monitor 26 displays a monitor image based on the video signal. Therefore, conventionally, an electric wire such as a coaxial cable which is wired between the camera section and the display section is not required.

In the embodiment of FIG. 2, first, the transmission operation of the main controller 1 will be described. The main control unit 11 transmits (transmits / receives) signals to / from each system unit and controls each system unit.
At this time, the SS modulation / demodulation unit 12 performs spread spectrum modulation and spread spectrum demodulation on the signals transmitted and received by the main control unit 11 using a required pseudo noise code. In the transmission / reception unit 13, the transmission converts the modulated signal into a required radio frequency, amplifies the power, and transmits the radio wave from the antenna 14. Also, in reception, the transmitted radio waves are received,
Low noise amplification and conversion to the required frequency. Next, the transmission operation of the detection control device 2 will be described. The detection control unit 15 inputs, for example, a detection signal from a human detection unit (not shown),
For example, a required control signal is output to the turning camera unit (not shown). At this time, the SS modulation / demodulation unit 12 and the transmission / reception unit 13 perform wireless transmission by the same operation as in the main control unit 11 described above.

Further, the video switching device 3, the character superposing device 4, or the voice switching device 5 wirelessly transmits a required transmission signal or reception signal by the same operation as in the above-mentioned main control section 11. .

FIG. 3 is a diagram showing a plurality of pseudo noise codes used for spread spectrum modulation of the video surveillance system according to the present invention. The pseudo noise code (PN code) used for spread spectrum modulation is PN1 for the bus control signal, and PN2.
For the video signal, PN3 for the detection control signal, and P
By assigning different codes to N4 for a voice signal and depending on the type of data, a plurality of channels are realized with one carrier frequency (2.4 GHz band or the like).

[0021]

As described above, the present invention provides a video surveillance system in which facility construction of the system is easy and construction cost is low. Therefore, in large-scale facilities such as steel mills and chemical plants, facility construction of the system is easy, and especially in buildings after construction that do not assume the system, wiring work etc. are almost unnecessary and the facility construction is unnecessary. There is an advantage that the cost can be reduced. Further, it is easy to change the system expansion later.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a video surveillance system according to the present invention.

FIG. 2 is a block diagram of a second embodiment of a video surveillance system according to the present invention.

FIG. 3 is a diagram showing a plurality of pseudo noise codes used for spread spectrum modulation of the video surveillance system according to the present invention.

FIG. 4 is a block diagram of an embodiment of a conventional video surveillance system.

[Explanation of symbols]

 1 main control device 2 detection control device 3 video switching device 4 character superimposing device 5 voice switching device 11 main control unit 12 SS modulation / demodulation unit 13 transmitting / receiving unit 14 antenna 15 detection control unit 16 video switching unit 17 character superposing unit 18 Audio switching unit 21 Camera 22 Modulating unit 23 Wireless transmitting unit 24 Wireless receiving unit 25 Demodulating unit 26 Monitor 27 Transmitting or receiving antenna 31 Main control device 32 Detection input / control device 33 Video switching device 34 Character superimposing device 35 Voice switching device 41 Human detection unit 42 Intrusion detection unit 43 Pivoting camera unit 44 First fixed camera 45 Second fixed camera 46 Microphone / amp unit 47 First image monitor 48 First operation unit 49 Image recording unit 50 Second image monitor 51 Second operation 52 Amp / Speaker

Claims (5)

[Claims] 1. A video monitoring system comprising a camera section and a display section for displaying a captured image from the camera section, wherein the video monitoring is provided with a transmission device for wirelessly transmitting the image of the camera section to the display section. system. 2. A camera unit, a display unit for displaying a captured image of the camera unit, a main control unit for controlling each unit of the system, and a detection control unit for inputting a detection signal and outputting a required control signal. A video switching device that selects an image signal transmission path between the camera unit and the display unit, a character superimposing device that superimposes characters on a captured image of the camera unit, and a voice switching device that selects a transmission path of an input voice. A video monitoring system comprising the main control device, the detection control device, a video switching device, a character superposing device, and a voice switching device, which are mutually connected by a wireless transmission path. 3. The video surveillance system according to claim 2, wherein the modulation system of the wireless transmission path is spread spectrum. 4. The video surveillance system according to claim 3, wherein a plurality of types of pseudo noise codes are used for said spread spectrum. 5. The video surveillance system according to claim 3, wherein the wireless transmission path has a frequency of 2.4 GHz band.