JPH03242797A - Image processor - Google Patents

Abstract

PURPOSE:To reduce the fatigue of a monitor concerned in monitoring work and to attain efficient monitoring by detecting the movement of an video displayed on a monitoring video camera, outputting an alarm and making it possible to emphasize the picture of the moving part. CONSTITUTION:The movement of the picture of an inputted video signal 10 is detected, a self-holding circuit 18 such as a timer circuit or a flip flop is started for a prescribed time by the output of a level discriminating circuit 17 and the output of the circuit 18 is outputted as an alarm signal 20. On the other hand, a difference signal 16 outputted from a comparator 15 is synthesized with a video signal outputted from an A/D converter 11 and the synthesized signal is converted into an analog signal 23 and outputted. A synchronizing signal 25 separated by the input video signal 10 is superposed to the video signal 23 outputted as the analog signal, the superposed signal is outputted as a signal 27 of an emphasized picture of the moving part out of the image of the signal 10 and the emphasized signal 27 can also be displayed on a video monitor. Thus, the fatigue of the monitor can be reduced by mechanizing a part of monitoring operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image processing device that processes a video signal from a surveillance video camera or the like and outputs a signal to be displayed on a video monitor.

[Conventional technology]

The time signal generated by an internal clock circuit is converted into a video signal and superimposed on the video signal output from a surveillance video camera, etc., and outputted, making it easy to confirm the time of occurrence of an event. .

In addition, the outputs of a plurality of monitoring video cameras, etc. were automatically switched at predetermined time intervals and displayed on two video monitors to facilitate monitoring.

[Problem to be solved by the invention]

Due to the purpose of use of surveillance video cameras and the like, they have a relatively wide field of view, so it is necessary to pay attention to changes in details and monitor the entire image displayed on the video monitor.

Such monitoring work requires a high degree of concentration over a long period of time, causing great mental fatigue on the supervisor.

The present invention provides a device that mechanizes a part of the monitoring described above and reduces the fatigue of the monitor.

[Means to solve the problem]

The input video signal from a surveillance video camera, etc. is converted into a digital signal, and the same video signal via frame memory is compared between frames, and the compared difference signal is used as an image motion summary when the signal continues at a predetermined level for a predetermined period of time. Output an alarm or alarm signal.

In addition, the difference signal obtained by comparing the frames of the video signal directly,
Alternatively, the same difference signal and the input signal to the frame memory are calculated and returned to an analog signal, and the signal is displayed on a video monitor with only the moving part or with the moving part emphasized.

[Effect]

A video signal 10 output from a surveillance video camera or the like is input, and the video signal No. 0 is converted into a digital video signal 12 by an A/D converter II.

The digitalized video signal 12 is stored in a frame memory 13.
and outputs a signal 14 which is time-delayed by one frame of the same video signal 12.

The one-frame delayed video signal I4 and the digitalized video signal No. 2 input into the frame memory 13,
Both are supplied to a comparator No. 5, which generates a difference signal 16 between the same video signal 12 and No. 4, and outputs the generated same difference signal 16.

For example, an exclusive OR operation is performed for each corresponding bit of the video signals 12 and 14, and a difference signal 16 between frames of the input video signal 10 is detected as a motion summary of the video signal 1o.

The difference signal I6 output from the comparator 5 is passed through a level discriminator circuit, for example, only a predetermined high-order bit of the same difference signal I6 is passed through an OR circuit to detect a signal higher than a predetermined level of the same difference signal 16, and eliminate noise. Or prevent malfunctions due to minute displacements, etc.

For example, if the number of quantization bits by the A/D converter 11 is 8 bits, the difference signal 16 output from the comparator 15 is
By performing an OR operation on the upper three bits of , it is possible to detect only signals with a level exceeding 1/8 of the full scale level.

The movement of the image of the input video signal 10 is detected through the above signal processing, and the output of the level discrimination circuit 17 activates a self-holding circuit 18 such as a timer circuit or flip-flop for a predetermined time, and the self-holding circuit 81θ is activated. The output is output as an alarm signal 20.

Further, the difference signal 16 outputted from the comparator 5 is transferred to the A/D.
converter! ! The synthesized signal is combined with the video signal outputted by the analog signal 23, and the synthesized signal is converted into an analog signal 23 and output.

A synchronizing signal 25 separated from the input video signal IO is superimposed on the video signal 23 converted to an analog signal and outputted, and outputted as an image signal 27 that emphasizes the moving part of the image of the input video signal 10. It can also be displayed.

For example, the video signal I2 output from the A/D converter ll
is shifted l bits downward to reduce the signal level to 1/2, the difference signal 16 output from the comparator 15 is shifted upwards by 1 bit to double the signal level, and the two signals are added together. This allows the moving parts of the same image to be emphasized.

〔Example〕

An embodiment of the present invention will be described.

The output of a surveillance video camera or the like is connected to the video input of this device, and the video output of this device is connected to a video monitor to configure a system.

The video signal 10 input to this device is supplied to an A/D converter that converts the video signal 10 into a digital signal 12, and is also supplied to a synchronization separation section 24 to generate a synchronization signal 25 included in the video signal 10. Separate.

The digitized video signal 12 output from the A/D converter 11 is supplied to a frame memory 13, and the signal No. 4 delayed by one frame period of the video signal 12 input to the frame memory 13 is sent from the frame memory 13. Output.

The video signal I2 input to the frame memory 13 and the video signal 14 output from the frame memory 13 are supplied to a comparator 15, and a difference signal between the video signals 12 and 14 is output.

The difference signal 16 output from the comparator 15 is input to a level discriminator NOR, and a signal exceeding a predetermined level of the same difference signal 16 is discriminated and output.

Using the signal output from the level discriminator 17 as a trigger signal, the state of the holding circuit 1B constituted by a flip-flop circuit is inverted and held in the same state.

The holding circuit 18 is constituted by an electromagnetic relay, and can be a self-holding circuit that holds the input state of the electromagnetic relay using the contacts of the electromagnetic relay.

Further, the holding circuit 18 may be constructed of a timer circuit, and may be held only for a predetermined period of time during which the timer circuit is operating.

The output of the holding circuit 18 is outputted as an alarm signal 20 to activate an external alarm lamp and/or alarm.

Further, the alarm signal 20 can also activate a small alarm lamp and/or an alarm provided inside the device.

The difference signal 16 output from the comparator 15 is branched and
The video signal 12 output from the /D converter 11 is supplied to the arithmetic unit 2I, the same difference signal I6 and the video signal 12 are added together, and the added signal is converted to an analog video signal 23 via the D/A converter 22. Convert.

The video signal 12 input to the arithmetic unit 2 is multiplied by a coefficient equal to or less than Bi', and the difference signal I6 is multiplied by a coefficient equal to or greater than Bi' and then subjected to an addition operation to emphasize the same difference signal 16. It can be output.

The analog video signal 23 is combined with a synchronization signal 25 separated by a synchronization separation circuit 24 from the analog video signal 10 input to the apparatus in a signal synthesis section 26, and a composite video signal 27 is output.

It is also possible to use a switcher that switches the video signals output from a plurality of video cameras to sequentially switch the video signals at predetermined time intervals, and input the switched output to the apparatus of the present invention.

〔Effect of the invention〕

According to the present invention, it is possible to detect the movement of the image captured by the surveillance video camera and output an alarm, and also to highlight the moving part of the image, so that the surveillance video camera can be used to monitor the surveillance work. This reduces worker fatigue, enables more monitoring, and allows for more efficient monitoring.

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is a block diagram of another embodiment of the present invention. In the figure, IO is an input video signal, 11 is an A/D converter, 12 is a digital video signal, 13 is a frame memory, 14 is a one frame delayed video signal, I5 is a comparator, 16 is a difference signal, 1
7 is a level discriminator, 8 is a holding circuit, 20 is an alarm signal output, 2 is an arithmetic unit, 22 is a D/A converter, 23 is an analog video signal, 24 is a synchronization separation section, 25 is a synchronization signal, 26
2 is a signal combining section, and 27 is an output video signal. Figure 1 Figure 2

Claims (3)

[Claims] (1) An A/D converter that converts the input video signal from a surveillance video camera, etc. into a digital signal, a frame memory that delays the digital signal by one frame period, and a difference signal between the signals input and output to the frame memory. and an alarm control section consisting of a circuit that discriminates the level of the difference signal output by the comparator and holds the discrimination output, and controls the alarm when the difference signal exceeds a predetermined level. An image processing device characterized in that an output of a holding circuit of the unit is output as an alarm signal. (2) a sync separator that separates a sync signal from the input video signal; a D/A converter that converts the difference signal output from the comparator into an analog signal; and a video output from the D/A converter. Claim (1) characterized in that it includes a synthesis section that superimposes the synchronization signal on a signal and outputs the same, and converts only the difference signal output from the comparator into an analog video signal and outputs it.
The image processing device described. (3) Processing the difference signal output from the comparator and the signal input to the frame memory, converting the processed signal into an analog signal and outputting it, and creating a video signal with the same difference signal emphasized. The image processing apparatus according to claim 2, characterized in that: