JPS60264180A - Supervisory equipment - Google Patents

Abstract

PURPOSE:To relieve the load of a supervisor by allowing a deciding circuit provided in the titled equipment to compare sequentially a detected video signal obtained from a luminance signal fetching circuit with a reference value signal generated in a reference value generating circuit and giving a fault deciding output when a change occurs. CONSTITUTION:When an external start signal S12 is fed to a drive control circuit 3, a timing control circuit 4 activates a selector 2, holds video signals VA-VD obtained by television cameras 1A-1D to hold circuits 10A-10D through input switch circuits 11A-11D of a luminance signal fetching circuit 5 and supplies them to a decision circuit 22 as a detected video signal VDT. On the other hand, a reference data stored in reference registers 26A-26D of a reference value generating circuit 25 is supplied to the deciding circuit 22 as the reference video signal, VRF, and when the video signals VA-VD are compared with the reference value and decided and when there is a change, discriminated outputs DTC1, DTC2 are generated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a monitoring device, and is particularly suitable for application to a monitoring device such as a security device using a plurality of television cameras.

[Raiden technology and its problems]

In conventional security devices such as television cameras,
By arranging multiple television cameras at locations to be monitored, such as entrances and exits, passageways, and rooms, and displaying the video signals obtained from each television camera on the display screen of a television monitor installed in the manager's room, for example. It is possible to remotely monitor multiple locations.

However, with this type of security device, conventional methods have been to install a monitor compatible with multiple television cameras for each camera, or to switch the video signals transmitted from multiple television cameras at regular intervals to display a single monitor. A method is adopted in which images are displayed one after another on a monitor screen.

If multiple monitor screens are provided, the burden on the supervisor is quite heavy as the supervisor must constantly visually check all the screens to see if there are any abnormalities. In this case, each time the video is switched, it is necessary to visually determine whether there is an abnormality on each screen, and this method also places an excessive burden on the monitor.

[Purpose of the invention]

The present invention has been made in consideration of the above points, and is capable of diagnosing an abnormality in one or more of the video signals obtained from a plurality of television cameras, detecting this, and notifying a supervisor. This paper attempts to propose a monitoring device with a simple configuration that enables the following. .

[Summary of the invention]

In order to achieve this purpose, in the present invention, video signals obtained from a plurality of television cameras are sequentially selected by a selector, taken into a brightness signal acquisition circuit, and held, and the monitoring location during normal operation is determined by the video signals obtained from the plurality of television cameras. A reference value corresponding to the video signal level obtained when photographing is generated by the reference value generation circuit, which is a video signal, and a reference value generated by the reference value generation circuit, which is a detected video signal obtained from the luminance signal acquisition circuit by the judgment circuit. The signals are sequentially compared and when a change occurs, an abnormal balance output is sent.

〔Example〕

An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, IA to ID are four television cameras, each of which is installed at a location to be monitored. The video signals VA-VD of the television cameras IA-ID are given to the selector 2, and are sequentially taken into the luminance signal taking-in circuit 5 in a predetermined order by the switching control signal S1 given from the timing control circuit 4 of the drive control circuit 3. It will be done.

Here, television cameras IA to ID are drive control circuits 3
They operate in synchronization with each other by a synchronization signal 82 generated by a synchronization signal generation circuit 6 provided in the same. At the same time, the timing control circuit 4 is provided with a synchronization signal S3 that is synchronized with the synchronization signal S2, so that the switching control signal S1 performs a switching operation sequentially for each section of the vertical synchronization signal,
In this way, the video signals VA-VD obtained from the television cameras IA-ID are selected field by field by the selector 2 and input to the luminance signal acquisition circuit 5.

The brightness signal acquisition circuit 5 is for television cameras IA to IDK.
It has corresponding hold circuits 10A to IOD, and turns on the input side switch circuits 11A to LID provided on each input side using the timing control circuit 40 control signal INCK, thereby controlling a predetermined value of the video signals VA to VD. Hold circuits 10A to 10 hold luminance signals corresponding to points at screen positions.
It is designed to take in DK.

In other words, of the screen FIG (Fig. 2) that can be photographed by cameras IA to ID, one or more areas (in the case of Fig. 2 To monitor whether the brightness of SO (one area) has changed or not, the timing control circuit 4 monitors the four coordinates (Xl, yl)% (x2) that partition the monitoring area SO on the screen FIG. .yl)-(
xt, y2)' (x2.y2), the input side switch circuits 11A~
11 Turn Dik on. As a result, the threshold circuits 10A to 10DK receive a luminance signal corresponding to a specific monitoring area SO on the screen FIG, and the corresponding monitoring area SO
This means that information representing the brightness of the image can be held.

Note that the number of monitoring areas SO is not limited to one, but may be set at multiple points as necessary. In this case, the timing control circuit 4 turns on the input side switch circuits 11A-11D at timings corresponding to the plurality of monitoring areas. do.

The luminance signal held in the hold circuits 10A to 10D in this way is the control signal OT of the timing control circuit 4.
Output side switch circuits 12A to 12 controlled by C
It is sent from the brightness 1 degree signal acquisition circuit 5 to the analog-digital conversion circuit 21 through Dk.

In this way, a detected video signal VDT having a digital value corresponding to the brightness in a specific monitoring area of the images taken by the television cameras IA to ID is obtained at the output end of the analog-digital conversion circuit 21, and this is detected by the judgment circuit n. given to.

The determination circuit η compares the detected video signal VDT with the reference video signal VRF obtained from the reference value generation circuit δ, and when the detected video signal VDT changes from the reference video signal VRF, determines this as abnormal and outputs determination outputs DTC1 and DTC2. Send.

The reference value generation circuit 5 is a television camera, IA to ID.
The luminance signal acquisition circuit 5 has reference value registers 26A to 26D that store as a reference value a signal level corresponding to the luminance of the monitoring area SO on the screen FIG obtained when the monitor is photographing a monitoring location in a normal state. is television camera IA-
When the detected video signal VDT is outputted via the output side switch circuits 12A to 12D corresponding to the IDK, the control signal INH given from the timing control circuit 4 at the same time.
The output side switch circuit 27A- is sequentially turned on by
The reference values stored in the reference value registers 26A to 26DK through the reference value registers 27D and 27D are respectively provided to the determination circuit n as a reference video signal VRF.

Here, the values of the reference value registers 26A to 26D are the detected video signals VDTK sequentially output from the luminance signal acquisition circuit 5.
Based on this, the reference value is calculated in the reference value calculation circuit and updated and stored in the reference value memo IJ 29.

7 for reference value memory 4 for television camera IA~I
The reference value stored in each memory area is connected to the reference value register 26A-2 through the input side switch circuits 30A-30D, which are each turned on by the timing control circuit 4.
The signal is transferred to 6DK and used as a reference video signal VRF.

The reference value calculation circuit array detects the currently arriving detected video signal VD.
When a change occurs in the detected video signal VDT even though there is no abnormality at the monitoring location after receiving the reference value data stored in the reference value memory 29, a new reference value is set in consideration of the change. is calculated and updated and stored in the reference value memo 1729 as a new reference value.

This is done when the lighting at the monitoring location changes, the temperature changes, or the elements of the television camera change over time even though there is no abnormality at the monitoring location. Second, when the signal level of the detected video signal VDT fluctuates due to this influence, the reference value level generated in the reference value calculation circuit array is corrected in accordance with this fluctuation. In this way, when the detected video signal VDT is compared with the reference video signal VRF in the judgment image W&n to obtain a judgment output, if the signal level of the detected video signal VDT has decreased, the Reference video signal V
Since the RF signal level also decreases at the same time, it is possible to effectively avoid the possibility of an adverse effect on the determination result in the determination circuit n.

The determination circuit n receives the detection video signals VDT corresponding to the television cameras IA to ID (then, in synchronization with this, the reference video signals V sequentially given from the reference value generation circuit 5).
Compared with RF, the detected video signal VDT is the reference video signal VR.
If it changes from F, it is determined that an abnormality has occurred, such as a person entering the monitoring place, and the determination outputs DTCI and DT are output.
Generates C2. The judgment output DTC1 is given as a switching control signal to the video signal selector. Video signal selector Aha TV camera IA~ID video signal VA~V
In response to D, a video signal determined to be abnormal by the determination circuit 22 among these video signals is selected by the determination output DTC1 and is applied to the monitor 36, for example, to display an image of the location where the abnormality has occurred on the monitor screen, This allows the supervisor to visually confirm the cause of the abnormality.

Judgment output DTC sent from judgment circuit n at the same time
2 is given to the external control circuit 37, and its drive output 5IO
K causes an alarm to be generated. This means that the supervisor is instructed to immediately look at the display screen on the monitor when the alarm is confirmed.

In this embodiment, the drive control circuit 3 has a timer 40,
The timer 40 captures the luminance signal into the luminance signal capture circuit 5 at predetermined time intervals and controls the reference value generation circuit 5 to capture the luminance signal.
The determination circuit 22 is configured to perform a determination operation based on the calculation and storage operation of the reference value.

Further, as described above with reference to FIG. 2, in order to capture the luminance signal of the monitoring area SO into the luminance signal acquisition circuit 5 by the control signal INC of the timing control circuit 40, the timing memory 41 is stored at a timing corresponding to the coordinates of the monitoring area SO. It is configured so that it can be set by a setting input S11 given from the outside.

Further, the drive control circuit 3 is configured to start the determination operation based on the video signals VA-VD at the timing when the timing control circuit 4 receives the external start signal 812 and receives the external luminance signal S12.

In the above configuration, the drive control circuit 3 and the external start signal 8
12 is given, or from the timer 40, the start signal 8
13, the timing control circuit 4 operates the selector 2 to output the video signals VA-VD and brightness signal acquisition circuit 50 obtained from the television cameras IA to ID through the input side switch circuit IIA-11D and the hold circuit 10A. ~Hold on IOD. The thus held luminance signal is sequentially given to the determination circuit 22 as the detected video signal VDT through the output side switch circuits 12A to 12D under the control of the timing control circuit 4.

On the other hand, in the judgment circuit ρ, the reference value data stored in the reference value registers 26A-260 of the reference value generation circuit 50 is sent to the reference value generation circuit 50 through the output side switch circuits 27A-Z7D as the reference value signal VR.
F and 5 marks are given the most on the road.

Therefore, the judgment circuit n judges whether or not the video signals VA-VD obtained from the four locations to be monitored have changed from the reference value, and when they have changed, the judgment output D
The video signal of the monitoring location where the TCI and DTC2 have occurred and the change has occurred is sent to the monitor 3 through the video signal selector 35.
6 and displayed on the display screen, the external control circuit 37 is activated and an alarm is generated.

Therefore, as soon as the supervisor hears the alarm, he or she can visually check the scene of the monitoring location where the abnormality has occurred by looking at the image on the monitor, and can quickly take countermeasures against the abnormality.

Therefore, according to the configuration shown in Figure 1, the supervisor only needs to look at the display screen of the monitor when an abnormality occurs in the place to be monitored, and thus the supervisory staff can It is possible to reduce the burden of

〔Effect of the invention〕

As described above, according to the present invention, the video signal VD is detected while sequentially switching video signals from a plurality of television cameras.
The presence or absence of an abnormality is determined by obtaining T and comparing the detected image gII signal obtained while being sequentially switched with the corresponding reference image signal, so this determination result can be used. Accordingly, it is possible to easily obtain a monitoring device that can significantly reduce the burden on the monitor.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a monitoring device according to the present invention, and FIG.
The figure is a route diagram for explaining the configuration of the luminance signal acquisition circuit. IA~ID...Television camera, 2...Selector, 3...Drive control circuit, 4...Timing control circuit, 5...Brightness signal acquisition circuit, 6...Synchronization signal generation circuit , 21...analog-digital conversion circuit, n.
... Judgment circuit, 5... Reference value generation circuit, A... Video signal selector, I... Monitor, 37... External control circuit.

Claims (1)

[Claims] A brightness signal acquisition circuit that sequentially selects and captures and holds video signals obtained from multiple television cameras with a selector, and a video signal level corresponding to the video signal level obtained when the monitoring location is photographed by the multiple television cameras in normal conditions. A reference value generation circuit that generates a base value video signal to be generated, and a detection video signal obtained from the luminance signal acquisition circuit are sequentially compared with a reference value signal generated in the reference value generation circuit, and when a change occurs. A monitoring device comprising: a determination circuit that sends out an abnormality determination output.