JPS6243286A - Television monitoring device - Google Patents

Abstract

PURPOSE:To omit constant monitoring by projecting the monitor signal to a TV receiver receiving general TV broadcast when some changes occur and this changing degree exceeds a fixed level. CONSTITUTION:A difference detecting circuit 2 detects some screen changes with video signals photographed by a camera. When the video signal exceeds a fixed level, this fact is discriminated and detected. Then a TV receiver screen 4 is changed to the signals of a monitor camera from the general broadcast screen (incl. other screens of a VTR, etc.) by the detection signal. Thus the general TV broadcast is usually received and a screen is projected on a TV only when the monitoring is required, i.e., the screen has a change.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to a TV monitoring device, and particularly to a factory.

Ideal for monitor TVs at entrances to buildings, etc. and home entrances.

[Background of the invention]

Conventional ITV TV monitoring devices simply photograph the subject to be monitored with a TV left camera, and either have a person constantly monitoring it or record it with a video tape recorder. However, this conventional method has the drawbacks that the person monitoring it cannot take their eyes off it even for a moment, and that the VT signal must be constantly recorded.

[Purpose of the invention]

The purpose of the present invention is to detect any change in the monitoring screen, and when the change exceeds a certain value, the monitoring screen is sent to the TV receiver that normally receives general TV broadcasts. The purpose is to project the signal.

[Summary of the invention]

In an ITV monitoring device, the present invention compares a field memory and the contents of this memory with a video signal after a certain period of time,
The above object is achieved by adding a circuit that detects the difference and issues an alarm signal when the difference exceeds a certain value, and by adding a function of switching the TV input based on this alarm signal.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Figure 1 shows an example of the configuration of this system. 1 is a TV power function, 2 is a memory of the screen (field or multiple lines) and a circuit that detects the difference between this memory and the screen after a certain period of time, 5 is an alarm when the difference exceeds a certain value A signal generating circuit 4 has a function of switching from the -film number transmission/reception state to the monitoring signal according to the alarm signal.
It is an rV receiver. FIG. 2 shows an example of the configuration of a two-difference detection circuit. 5 is a field memory that stores one screen of the video signal or a line memory that stores multiple line signals; 6 is a difference detection circuit that compares the memory output with the video signal after a certain period of time and outputs the difference signal. be.

The operating principle is shown in the figure below.

In the video signal taken by the camera, the difference detection circuit 2 detects any change in the screen, and if that signal exceeds a certain value, it is identified and detected, and the detection signal is used to control the TV receiver 4. Switch the screen from the general broadcast screen (or other screens such as ■T) to the signal from the surveillance camera.

(Effects of the Invention) In the past, the supervisor had to constantly watch the TV monitor, but according to the present invention, the supervisor is always watching the TV with multiple screens, and the need for monitoring has arisen. The screen will be displayed on the TV only when there is a change in the screen.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of an embodiment of the present invention.
FIG. 2 is a detailed diagram of the difference detection circuit in FIG. 1; 1...TV camera, 4...TV receiver aircraft, 6
...Difference detection circuit.

Claims (1)

[Claims] 1. In a TV monitoring device, there is a field memory that can store one field of a video signal, a circuit that compares the contents of this memory with a video signal after a certain period of time and detects the difference, and a circuit that detects the difference when the difference exceeds a certain value. A TV monitor comprising: a circuit that issues an alarm signal when a warning signal is received; and a TV receiver that normally receives a general broadcast signal and has a function of switching to a TV monitoring signal only when the alarm signal is received. Device.