JPH08212465A - Crime prevention system using monitor camera - Google Patents

Abstract

PURPOSE: To provide the crime prevention system which uses the monitor camera that can be installed in a place wherein the privacy is given importance. CONSTITUTION: A pulse signal from a pulse generating circuit 13 is applied to a signal generated by digitizing the output of a solid image pickup element 2 and a hard-to-see image which having a mixed noise is projected on a monitor 120. After the presence of a trespasser is detected in this state, the generation of the pulse signal is stopped through watcher's operation and a clear image having no noise is projected on the monitor 120. Consequently, the monitor camera can be installed in the place wherein the privacy is given importance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security system using a surveillance camera used for indoor surveillance of office buildings and the like.

[0002]

2. Description of the Related Art Conventionally, as a monitoring camera used for monitoring the inside of an office building, for example, Japanese Patent Application No. 63-6
No. 6316 (Public utility model application publication 1993 26858)
No.). This type of surveillance camera has a housing 70 that covers the camera body in order to prevent the surveillance status from being known to people in the surveillance area.
Aluminum is vapor-deposited at a thickness that results in a transmittance of%, and a light-shielding paint is applied on the aluminum vapor-deposited layer other than in the photographing direction of the camera. Since only the aluminum deposition is applied to the portion of the housing in the photographing direction of the camera, the camera can photograph the surveillance area through the portion. On the other hand, a person in the surveillance area does not notice the presence of the camera in the housing due to the light-shielding paint applied to the portion of the housing other than the photographing direction of the camera.

[0003]

By the way, in the above-mentioned conventional surveillance camera, the portion of the housing corresponding to the photographing direction of the camera has a high transmittance so that the photographed image is always easy to see. There was a problem that it could not be applied to applications that require respect for the privacy of people in the area. Therefore, an object of the present invention is to provide a crime prevention system using a surveillance camera that can be installed in a place where privacy is respected.

[0004]

In order to achieve the above object, a security system using a surveillance camera according to a first aspect of the present invention comprises a surveillance camera, a noise signal generating means for generating a noise signal, and this noise. It is characterized by further comprising noise applying means for applying a noise signal output from the signal generating means to the video signal of the surveillance camera, and display means for displaying an image photographed by the surveillance camera.
Further, as a preferred embodiment, for example, as in the invention described in claim 2, the operating means provided on the display means, the permitting means for permitting the operation of the operating means only when an intruder exists, and the operating means. And a noise signal generation stopping means for stopping the generation of the noise signal by the noise signal generating means. A security system using the surveillance camera according to the invention of claim 3 is interposed between the surveillance camera and an optical system of the surveillance camera,
It is characterized in that it is provided with a blurring means for blurring the optical image, and a display means for displaying the image photographed by the surveillance camera through the blurring means. For example, claim 4
As in the invention described above, the blurring means may be an optical filter or a sensor cover arranged in front of the lens of the surveillance camera.

[0005]

According to the present invention, when a noise signal is applied to the video signal of the surveillance camera, an invisible image in which noise is mixed is displayed on the display means. When the presence of an intruder is detected in this state, the generation of the noise signal is stopped and a clear image without noise is displayed on the display means. Furthermore, in the present invention, when an optical filter or a sensor cover for blurring an image is interposed in the optical system of the surveillance camera,
A blurry image is displayed on the display means. When the presence of an intruder is detected in this state, the optical filter or the sensor cover is removed from the optical system of the surveillance camera to display a clear image. Therefore, when there is an intruder, the surveillance area can be clearly displayed, so that it can be installed in a place where privacy is respected.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a security system using the surveillance camera of the present invention will be described below with reference to the drawings.
FIG. 1 is a circuit diagram showing the configuration of an embodiment of a crime prevention system using a surveillance camera according to the present invention. A. Configuration of Security System Using Surveillance Camera (a) Circuit Configuration In FIG. 1, 1 is a lens and 2 is a CCD (Charge Couple).
d Device) or solid-state imaging device such as MOS (Metal Oxide Silicon), 3 is a video filter, 4 is a preamplifier, and 5 is an A / D conversion circuit.

The digital signal from the A / D conversion circuit 5 is taken in by the control section 6 and supplied to the warning area confirmation switching circuit 7. The control unit 6 includes a CPU and a ROM (not shown).
And a RAM (work memory or image memory) and the like, and the ROM stores a program for controlling the CPU. According to the program stored in this ROM, the digital signal from the A / D conversion circuit 5 is fetched at predetermined intervals, and the fetched digital signal is compared with the previous digital signal stored in the memory (eg RAM) 8. Based on each of the identification conditions set by the identification condition setting circuit 9, it is determined whether or not there is an intruder. If it is determined that the user is an intruder in this determination, the alarm output circuit 10 is operated and the display circuit 11 displays an indication of the intrusion. The digital signal fetched from the A / D conversion circuit 5 is stored in the memory 8 for use in the next comparison. In the work memory of the control unit 6, a plurality of registers for storing the respective identification conditions set by the identification condition setting circuit 9 are set.

The identification condition setting circuit 9 sets the amount of change in brightness, the size of the video block, the condition for determining human movement, and the like, and the control unit 6 determines the presence of an intruder based on these settings. It is determined whether or not to do it. The alarm output circuit 10 is provided with a relay (not shown), and its contact is closed in response to a command from the control unit 6. The contact output of the alarm output circuit 10 is supplied to the receiver 110 of the monitoring center 100 via the terminal T ₁ . The receiver 110 detects the abnormality by capturing the contact output. The display circuit 11 includes an LED (light emitting diode), EL
(Electroluminescence), a liquid crystal display, a plasma display, or the like is provided, and displays based on display data from the control unit 6.

A generation cycle adjusting circuit 12 adjusts the cycle of the pulse signal generated by the pulse generating circuit 13 according to a control signal supplied from the outside (0 Hz to).
A control signal for adjusting the cycle of the pulse signal is supplied from a control panel (not shown) provided in the monitor 120 of the monitoring center 100 via the terminal T ₂ . The monitor adjusts the cycle of the pulse signal generated by the pulse generation circuit 13 by operating the volume 130 of the operation panel. By this adjustment, the influence of the pulse signal on the digital signal from the A / D conversion circuit 5 changes, and the proportion of the disturbance of the image displayed on the monitor 120 changes. A coaxial cable 140 is used for connection between the terminal T ₂ and the monitor 120, and the coaxial cable 140 mixes and transmits the DC level control signal and the digital signal from the A / D conversion circuit 5.

The pulse signal from the pulse generating circuit 13 is taken into the caution area confirmation switching circuit 7 and mixed with the digital signal from the A / D conversion circuit 5, and then the terminal T ₂
Is supplied to the monitor 120 of the monitoring center 100 via. By mixing the pulse signal with the digital signal from the A / D conversion circuit 5, as described above, the monitor 120
Distortion occurs in the image displayed on the screen. The warning area confirmation switching circuit 7 is provided with a switch (not shown), and this switch selects whether or not to take in the pulse signal from the pulse generating circuit 13, and is an adjustment when installing the crime prevention system. Sometimes used.

Next, the operation of the crime prevention system using the surveillance camera thus constructed will be described. B. Operation of Security System Using Surveillance Camera (a) Operation of Control Unit 6 FIG. 2 is a flowchart showing the operation of the control unit 6. After the power is turned on, first, in step S10, various registers of the memory 8 are initialized. Next, in step S12, each condition setting value of the identification condition setting circuit 9 is read and stored in each register of the memory 8. After performing this process, the process proceeds to step S14, where A
The output of the / D conversion circuit 5 is fetched, and the output is stored in the register of the memory 8 in step S16.

After the output of the A / D conversion circuit 5 is fetched and stored in the register of the memory 8, the previous output of the A / D conversion circuit 5 and the current A / D conversion circuit are processed in step S18.
The output of the conversion circuit 5 is compared based on each condition setting.
Then, it is determined in step S20 based on the comparison result whether or not an intruder exists. If it is determined that there is no intruder in this determination, the process returns to step S14.
On the other hand, if it is determined that an intruder exists, step S
In step 22, the command is given to the alarm output circuit 10. As a result, the relay contact of the alarm output circuit 10 is closed,
The contact output is supplied to the receiver 110 of the monitoring center 100 via the terminal T ₁ .

After giving a command to the alarm output circuit 10, the process proceeds to step S24, and an alarm display for notifying the presence of an intruder is displayed. After performing this processing, it is determined in step S26 whether or not there is an alarm release. If it is determined that the alarm is not released in this determination, the process returns to step S22, and if it is determined that the alarm is released, the process proceeds to step S26 and the alarm is released. That is, the command to the alarm output circuit 10 is stopped and the relay contact of the alarm output circuit 10 is opened. Further, the alarm display is stopped. After performing this process, the process returns to step S14.

(B) Operation of the generation cycle adjusting circuit 12 While the digital signal from the A / D conversion circuit 5 is taken in by the control section 6, the warning area confirmation switching circuit 7 outputs a signal to the terminal T.
_2. It is supplied to the monitor 120 of the monitoring center 100 through the coaxial cable 140. At this time, when the observer operates the volume 130 provided on the operation panel of the monitor 120, a control signal corresponding to the operation is supplied to the generation cycle adjusting circuit 12 through the coaxial cable 140 and the terminal T _2. . When the generation cycle adjusting circuit 12 receives the control signal, it adjusts the cycle of the pulse signal of the pulse generating circuit 13 according to the control signal.

The pulse generation circuit 13 is a generation cycle adjustment circuit 1
A pulse signal having a cycle adjusted by 2 is generated and supplied to the caution area confirmation switching circuit 7. As a result, the pulse signal is applied to the digital signal from the A / D conversion circuit 5. The digital signal to which the pulse signal is applied is supplied to the monitor 120. When a control signal for setting the cycle of the pulse signal to "0" is supplied to the generation cycle adjusting circuit 12, the output of the pulse generation circuit 13 becomes substantially zero, so that the A / D
The digital signal from the conversion circuit 5 is output as it is through the terminal T ₂ . As a result, a clear image as it was captured by the solid-state image sensor 2 is displayed on the monitor 120.

As described above, in this embodiment, the pulse generation circuit 1 converts the output of the solid-state image pickup device 2 into a digital signal.
The pulse signal from No. 3 is applied, and a hard-to-see image in which noise is mixed is displayed on the monitor 120. After the presence of an intruder is detected in this state, the generation of the pulse signal is stopped by the operation of the observer, and a clear image without noise is displayed on the monitor 120. Therefore,
It can be installed in a place where privacy is respected.
Also, since the pulse signal is applied to the digital signal,
Since the pulse signal can be easily applied to and removed from the digital signal, the circuit configuration can be simplified, and the increase in cost can be minimized.

The present invention is not limited to the above embodiments, and various embodiments are possible within the scope of the object of the present invention. Specifically, the following may be done. (A) Although the period of the pulse signal of the pulse generation circuit 13 is adjusted by operating the volume 130 of the monitor 120, the period of the pulse signal is set to "0" and a predetermined value not by the volume but by a simple switch. It may be selected. This simplifies the structure of the generation cycle adjusting circuit 12 and leads to cost reduction. (B) Further, the cycle of the pulse signal may be adjusted by the control unit 6 without operating the volume 130 of the monitor 120. In this way, when there is an intruder, a clear image can be displayed without waiting for the operation of the monitor.

(C) In the above embodiment, the A / D conversion circuit 5
The image is blurred by applying the pulse signal from the pulse generation circuit 13 to the digital signal from the lens. However, this method is not used. For example, an optical filter having a blurring effect is provided in front of the lens 1 or the lens 1. May be interposed between the solid-state image sensor 2 and the solid-state image sensor 2, or a sensor cover having a blurring effect may be used. Needless to say, in this case, the caution area confirmation switching circuit 7, the generation cycle adjusting circuit 12, and the pulse generating circuit 13 are unnecessary.

(D) When an optical filter or sensor cover having a blurring effect is used and an intruder is present, the optical filter or sensor cover is attached to the solid-state image sensor 2 in order to clarify the image on the monitor 120. Although it must be removed from the optical system, a switch is provided on the monitor 120 and a mechanism for removing the optical filter or the sensor cover from the optical system is provided. Then, by operating the switch provided on the monitor 120, the optical filter or the sensor cover is removed from the optical system of the solid-state imaging device 2.

[0020]

According to the present invention, the following effects can be obtained. (1) A noise signal is applied to the video signal of the surveillance camera so that an incomprehensible image in which noise is mixed is displayed on the display means, and when an intruder is detected in this state, the noise signal Since the generation is stopped and a clear image with no noise is displayed on the display means, it is possible to install in a place where privacy is respected. (2) An optical filter or a sensor cover for blurring an optical image is interposed in the optical system of the surveillance camera so that a blurred image is displayed on the display means.
When an intruder is detected in this state, the optical filter or sensor cover was removed from the optical system of the surveillance camera to display a clear image on the display means. Can be installed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of an embodiment of a crime prevention system using a surveillance camera according to the present invention.

FIG. 2 is a flowchart showing an operation of a control unit of a security system using the surveillance camera of the same embodiment.

[Explanation of symbols]

 2 Solid-state image sensor 5 A / D conversion circuit 6 Control unit 7 Warning area confirmation switching circuit 8 Memory 9 Identification condition setting circuit 10 Alarm output circuit 11 Display circuit 12 Pulse generation cycle adjusting circuit 13 Pulse generation circuit 100 Monitoring center 110 Receiver 120 Monitor 130 volume

Claims (4)

[Claims] 1. A monitoring camera, a noise signal generating means for generating a noise signal, a noise applying means for applying a noise signal output from the noise signal generating means to a video signal of the monitoring camera, and the monitoring A security system using a surveillance camera, comprising: a display unit for displaying an image captured by the surveillance camera. 2. The operating means provided on the display means, the permitting means for permitting the operation of the operating means only when an intruder is present, and the noise signal generating means in response to the operation of the operating means. The security system using the surveillance camera according to claim 1, further comprising: a noise signal generation stopping unit that stops generation of a noise signal. 3. A surveillance camera, a means for blurring an optical image, which is interposed in an optical system of the surveillance camera, and a display means for displaying an image photographed by the surveillance camera through the blurring means. A security system using a surveillance camera, which is characterized by being equipped with. 4. The security system using the surveillance camera according to claim 3, wherein the blurring means is an optical filter or a sensor cover which is arranged in front of the lens of the surveillance camera with a space therebetween. .