JP2000298778A - Monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To optimally set a discriminating level for discriminating whether there is an abnormality in a monitoring device for detecting any abnormality, such as an intruder by an inside alarm due to the change in a luminance signal. SOLUTION: In a monitoring device 1 by an inside alarm, an outside alarm detector 3 for detecting abnormality by an outside alarm due to the change in infrared rays is connected with an inside alarm detector, and the detection level of the outside alarm and the detection level of the inside alarm are set as the same level. Moreover, at setting of plural monitoring positions, alarm values of the plural monitoring positions are all set as the same alarm value so that highly precise abnormality detection can be attained, even at setting of plural monitoring positions by the inside alarm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surveillance camera control device, and more particularly to a technique for detecting an abnormality such as an intruder from a video image input to a camera.

[0002]

2. Description of the Related Art In a camera monitoring apparatus, when detecting an intruder or the like, an external alarm (heat / infrared ray) and an internal alarm (difference in time-series luminance level of an input camera image) are widely used. ing.

[0003] Here, the internal alarm captures an image of each monitoring position in a normal state and stores it in advance.
A difference between an image captured at a constant interval from the camera and the stored image is detected, and when the difference exceeds a threshold value, an abnormality is detected as a change in the monitoring position. That is, if the monitoring point of one dot is, for example, 8 bits, the monitoring area is 12 (2 × 8) dots, and this 12
The value of the bit is compared with a threshold value to determine whether there is an abnormality. In this case, the maximum value of the difference is 12
Bit.

On the other hand, an external alarm performs a difference operation for each pixel at regular intervals for an infrared image indicating a temperature distribution of an object in the field of view of the infrared camera, performs a threshold process, and sets a temporal temperature equal to or higher than a predetermined value. An abnormality is detected by detecting a change. For example, JP-A-62-162939 and JP-A-63-2212 are examples of known external alarms.
No. 26, and the like.

[0005] External alarms are generally more accurate than internal alarms, but are more expensive, and it is often difficult to set multiple monitoring locations with a single device. On the other hand, internal alarms are inexpensive and can be used to set multiple monitoring positions with a single device, which is convenient. However, it is difficult to set thresholds for judging abnormalities such as the entry of people in the monitoring area. It responds excessively to the degree of the light, or does not respond even though a person has entered and is in an abnormal state.

[0006]

The internal alarm requires accuracy in setting the threshold value, and depending on the setting, a malfunction (erroneous determination) may occur.

That is, in the case of an internal alarm, if the threshold range is too large, no abnormality can be detected despite the presence of an intruder. Conversely, if the threshold range is too small, the light is shaded and abnormal. May be detected. Therefore, it is difficult to detect abnormalities with high accuracy by using only the internal alarm.

On the other hand, the external alarm has a higher detection accuracy than the internal alarm, but is expensive and often has difficulty in providing a plurality of detection positions on one screen.

According to the present invention, when an inexpensive internal alarm is used, abnormality detection with high accuracy similar to that of an external alarm is performed.

[0010]

According to a first aspect of the present invention, there is provided a monitoring apparatus comprising:
In a monitoring device that detects a change in a luminance signal to determine a person's entry or the like, an alarm setting unit that sets an alarm value serving as a reference for determining a change in the luminance signal, and a change in an infrared ray or the like at a position to be monitored. External alarm input means for inputting an output from an external alarm detection device for monitoring an abnormality and detecting an abnormality, video signal input means for inputting a video signal of a monitoring area, and monitoring of the monitoring area to be monitored Monitoring position setting means for setting a position; Y / C separation means for separating a luminance signal and a chroma signal from a video signal inputted to the video signal input means; and a digital signal for converting the luminance signal from the Y / C separation means. A / D conversion means for converting the A
Integrating means for extracting a signal at the position set by the monitoring position setting means from the digital signal output from the / D converting means and integrating the signal, and comparing the value integrated by the integrating means with the previously integrated value. Alarm determining means for outputting an alarm when the difference between the integral values exceeds the alarm value set by the alarm setting means, and a monitoring position set by the external alarm detecting device and the monitoring position setting means. By setting the position to be the same monitoring position and setting the alarm value so that the detection level of the external alarm detection device and the detection level of the internal alarm become the same detection level, a highly accurate abnormal It is a monitoring device that can detect.

According to a second aspect of the present invention, in the monitoring apparatus of the first aspect, when a plurality of monitoring positions are set, the alarm values at the plurality of monitoring positions are all set to the same alarm value. This is a monitoring device that can perform highly accurate abnormality detection even when a plurality of positions are set.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. FIG. 1 is a block diagram of the monitoring apparatus according to the present embodiment, FIG. 2 is a diagram showing a monitoring position of a monitoring area, and FIG.
FIG. 4 is a flowchart illustrating a determination operation of abnormality detection according to the present embodiment.

As shown in FIG. 1, the monitoring device 1 of the present embodiment
Is a camera 2 for inputting a video to be monitored, an external alarm detection device 3 for detecting an external alarm and outputting the result, and a Y / C separation for separating a video signal from the camera 2 into a chroma signal and a luminance signal. A circuit 4, an A / D conversion circuit 5 for converting a luminance signal, which is an analog signal separated by the Y / C separation circuit 4, into a digital signal, and an abnormal signal from the luminance signal converted into a digital signal by the A / D conversion circuit 5. G / A circuit 6 and G / A circuit 6 comprising a gate array for judging alarm)
And a microcomputer (hereinafter referred to as a microcomputer) 7 for inputting an alarm from the external alarm detection device 3 and for giving a monitoring position and an alarm judgment standard (alarm level) to the G / A circuit 6 and for outputting a sensor 8. ing.

The setting of the monitoring position of the monitoring area to be monitored is as follows:
The monitoring area captured from the camera 2 is displayed on a monitor, and a position to be monitored in the monitoring area is set. The setting of the monitoring position is performed by dividing the monitoring area shown on the monitor into squares 240 in the vertical direction and 720 in the horizontal direction as shown in FIG. 2 and designating the squares. Specifically, in the case of NTSC, a horizontal scanning line of a signal of one field is counted by a counter every 63.55 μsec, and divided into about 240 in the vertical direction. 720 (approximately 74 μsec cycle). The actual monitoring position is set by enclosing the monitoring position with a line by an OSD (on-screen display) in accordance with an instruction from a keyboard (not shown) or the like with respect to the monitoring area displayed on the monitor. Therefore,
The area surrounded by the line is the monitoring position to be monitored by the monitoring device of the present embodiment.

Next, the operation of the monitoring device 1 will be described. From the video signal captured from the camera 2, only the luminance signal is extracted by the Y / C separation circuit 4, and the luminance signal is
The digital signal is converted by the / D conversion circuit 5. The luminance signal converted into the digital signal is input to the G / A circuit 6, extracts data from a monitoring position set in advance and instructed by the microcomputer 7, and integrates the data. Specifically, the luminance signal from the Y / C separation circuit 4 is converted by the A / D conversion circuit 5 into a value of 255 to 0 according to the luminance level, and data corresponding to the monitoring position is extracted. Integrate the data.

The microcomputer 7 sets an alarm value (reference value) in the G / A circuit 6 in advance. The alarm value is G /
When the difference between the value of the data previously extracted and integrated by the A-circuit 6 and the integrated value of the data extracted and integrated this time exceeds a certain range, an alarm is sent to the microcomputer assuming that the monitoring position is abnormal. (A constant range).

The G / A circuit 6 calculates the luminance signal data for each odd-numbered field or even-numbered field. Output detection.

This time, the alarm value is set. As shown in the flowchart of FIG. 3, the monitoring positions of the internal alarm and the external alarm of the external alarm detecting device 3 are set to the same position (S1). Next, set the alarm level of the internal alarm to the minimum level (the most responsive) where the alarm does not work even if the brightness level changes due to light shading (S
2) In this state, while giving a change in luminance level (such as entry of a person into the monitoring area) that is desired to be detected by an external alarm.
(S3), the internal alarm level is raised by one (in a direction in which detection is difficult) (S4). Then, it is determined whether or not the internal alarm detects a change (penetration of a person) (S5), and steps 4 and 5 are sequentially repeated until the internal alarm cannot be detected. When the internal alarm has reached a level at which a change cannot be detected (S5), the process proceeds to step 6, where the internal alarm level is lowered by one (in a direction in which detection is easy) (S6), and the setting of the internal alarm is terminated (S7).

Further, when a plurality of monitoring positions are set in the monitoring apparatus of the present embodiment, the same alarm value is set in all the monitoring positions, so that a highly accurate abnormality can be detected in all the monitoring positions. Becomes

[0020]

By setting the detection level of the internal alarm as described above, it is possible to prevent the alarm from being overdriven and the alarm from being overdriven. That is, even though there is no abnormality in the actual monitoring area, there is an excessive response due to the shadow of light, or conversely, even if an alarm level is set broadly to prevent overreaction and there is actually a person entering, etc. It is possible to prevent malfunctioning, and it is possible to detect an abnormality with high accuracy by using an internal alarm as with an external alarm.

[Brief description of the drawings]

FIG. 1 is a block diagram of an internal alarm level setting device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a monitoring position of a monitoring area according to an embodiment of the present invention.

FIG. 3 is a flowchart illustrating a determination operation of abnormality detection according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Monitoring device, 4 ... Y / C separation circuit, 5 ... A / D conversion circuit, 6 ... G / A circuit, 7 ... Microcomputer, 8 ... Sensor output

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Claims (2)

[Claims] An alarm setting means for setting an alarm value serving as a reference for judging a change in a luminance signal, wherein the position is to be monitored. External alarm input means for inputting an output from an external alarm detection device for detecting a change in infrared rays or the like to detect an abnormality, video signal input means for inputting a video signal of a monitoring area, and the monitoring area Monitoring position setting means for setting a monitoring position to be monitored, Y / C separation means for separating a luminance signal and a chroma signal from a video signal input to the video signal input means, A / D conversion means for converting a luminance signal into a digital signal; and extracting and integrating a signal at a position set by the monitoring position setting means from the digital signal output from the A / D conversion means. Integrating means for comparing the value integrated by the integrating means with the previously integrated value and outputting an alarm when the difference between the integrated values exceeds the alarm value set by the alarm setting means; Means, wherein the monitoring position of the external alarm detection device and the monitoring position set by the monitoring position setting means are the same monitoring position, and the detection level of the external alarm detection device and the detection level of the internal alarm are changed. A monitoring device, wherein the alarm value is set so as to have the same detection level. 2. The monitoring device according to claim 1, wherein when a plurality of monitoring positions are set, all alarm values of the plurality of monitoring positions are set to the same alarm value.