JPH08322039A - Monitoring camera system - Google Patents

Abstract

PURPOSE: To provide a monitoring camera system capable of displaying a distance mark signal representing distance from a following vehicle behind a driving vehicle concerned on a monitor. CONSTITUTION: The rearward side of the vehicle is photographed with an image pickup camera 1 mounted on the rear side of the vehicle, and a vertical synchronizing signal and a horizontal synchronizing signal are separated from an outputted video signal by a synchronizing separator circuit 6. A gate signal with pulse width in correspondence with one horizontal scanning time is outputted from the input of the vertical synchronizing signal based on the vertical and horizontal synchronizing signals after the lapse of a prescribed time set in advance by a time setting circuit 9. The distance mark signal whose luminance is adjusted by a variable resistor 21 is outputted from a switch circuit 6 by the gate signal 16. In this way, the distance mark signal is displayed on the monitor 20 by superimposing on the video signal, and the distance from the vehicle of a display image is confirmed quantitatively by the distance mark signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surveillance camera system used, for example, for monitoring the rear of a vehicle, and more particularly to a circuit for displaying the distance from a surveillance camera to a subject.

[0002]

2. Description of the Related Art A surveillance camera is attached to a rear portion of a vehicle in order to check an obstacle behind the vehicle when traveling backward and to monitor an approaching vehicle traveling behind the vehicle while traveling.
The video signal captured by the surveillance camera is displayed on a monitor, and the rear of the vehicle is monitored from the driver's seat by the display image on the monitor. Since this type of surveillance camera uses a wide-angle lens, the distance from the vehicle in the image displayed on the monitor is different from that displayed on the monitor. Judging is different from the actual situation and can be dangerous.

Therefore, in the conventional surveillance camera, the model object is arranged at a predetermined distance from the vehicle, and a mark line indicating the distance from the vehicle corresponding to the position of the displayed image on the monitor is printed on the monitor. It was added by means such as to prevent accidents caused by incorrect measurement.

[0004]

However, the position to which the mark line is added differs depending on the optical characteristics of the surveillance camera and the electrical characteristics of the monitor, and the model object is displayed for each combination of the surveillance camera and the monitor. It was necessary to set the mark, and the work of adding the mark line was extremely complicated.

The present invention has been made in view of such circumstances, and an object thereof is a surveillance camera system capable of easily displaying a distance mark signal indicating a distance from a mounting position of a camera on a monitor. To provide.

[0006]

In order to achieve the above object, the surveillance camera system of the present invention separates a vertical synchronizing signal and a horizontal synchronizing signal from an image pickup means and a video signal output from the image pickup means. And a gate signal output means for outputting a gate signal having a pulse width corresponding to one horizontal scanning time based on the vertical synchronizing signal and the horizontal synchronizing signal after a predetermined time has passed from the input of the vertical synchronizing signal. Display means for displaying the distance mark signal by superimposing it on the video signal by the output of the gate signal.

Further, the surveillance camera system of the present invention has adjusting means for adjusting the predetermined time of the gate signal output means. Further, it has a brightness adjusting means for adjusting the brightness of the distance mark signal displayed by the display means.

[0008]

According to the surveillance camera system of the present invention, the rear of the vehicle is photographed by the image pickup means attached to the rear portion of the vehicle, and the video signal thereof is inputted to the sync separation means. The sync separation means separates the vertical sync signal and the horizontal sync signal from the video signal from the imaging means.
Further, after the vertical synchronizing signal is input by the gate signal output means, for example, after a predetermined time preset by the adjusting means, a gate having a pulse width corresponding to one horizontal scanning time is generated based on the vertical synchronizing signal and the horizontal synchronizing signal. The signal is output. Then, by the output of the gate signal on the display means, for example, a distance mark signal whose brightness is adjusted by the brightness adjusting means is displayed superimposed on the video signal, and the distance of the display image from the vehicle is quantitatively confirmed. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment FIG. 1 is a system block diagram showing the configuration of a first embodiment of a surveillance camera system according to the present invention, FIG. 2 is an explanatory view of a monitor display of this embodiment, and FIG. 6 is a time chart showing the operation of the present embodiment.

As shown in FIG. 1, this system includes an amplification and shaping circuit composed of a capacitor 2, a buffer 3 including an emitter follower, and a capacitor 4 connected in series to an output terminal of an image pickup camera 1 for photographing the rear of a vehicle. 5, the sync separation circuit 6 and the switch circuit 7 are connected in parallel to the output terminal of the amplification and shaping circuit 5. Then, the vertical sync signal / VS which is the two outputs of the sync separation circuit 6
YNC (/ indicates inversion) and horizontal sync signal HSYNC
Gate signal output for outputting a gate signal S16 having a pulse width corresponding to one horizontal scanning time based on the vertical synchronization signal / VSYNC and the horizontal synchronization signal HSYNC after a predetermined time has elapsed since the input of the vertical synchronization signal / VSYNC after receiving C A circuit 8 is provided.

The gate signal output circuit 8 has an output terminal of a timer circuit 12 having a time setting circuit 9 in which a variable resistor 10 and a capacitor 11 are connected in series between a bias terminal and ground, and an inverter 13 to the output terminal. The JK flip-flop 14 is connected, the J1 terminal of the JK flip-flop 15 and one input terminal of the AND circuit 16 are connected in parallel to the Q1 terminal of the flip-flop 14, and the / Q2 terminal of the flip-flop 15 is connected. , And is connected to the other input terminal of the AND circuit 16.

The vertical sync signal of the sync separation circuit 6 /
The output terminal of VSYNC is connected to the drive terminal of the timer circuit 12 and the reset terminals of the flip-flops 14 and 15, respectively, and the horizontal sync signal HSY of the sync separation circuit 5 is connected.
The output terminal of the NC is connected to the C terminal of the flip-flop 14, and is also connected to the C terminal of the flip-flop 15 via the inverter 18.

Further, the common terminal t0 of the switch circuit 7
Is connected to the monitor 20 via the capacitor 19, the switching terminal t1 of the switch circuit 7 is connected to the output terminal of the amplification shaping circuit 5, and the sliding terminal of the variable resistor 21 connected between the bias terminal and the ground is , And is connected to the switching terminal t2 of the switch circuit 6 via the amplifier 22.

Next, the operation of the above configuration will be described. The rear side of the vehicle is photographed by the imaging camera 1, the video signal from the imaging camera 1 is amplified and shaped by the amplification and shaping circuit 5, and then input to the sync separation circuit 6 and the switch circuit 7. In the sync separation circuit 6, the video signal is a vertical sync signal /
The VSYNC and the horizontal synchronizing signal HSYNC are separated, the vertical synchronizing signal / VSYNC is output to the reset terminal R of the timer circuit 12 and the flip-flops 14 and 15, and the horizontal synchronizing signal HSYNC is passed to the C terminal of the flip-flop 14 and the inverter 18. C of flip-flop 15
It is output to the terminal.

Vertical sync signal separated from video signal /
When VSYNC is input to the timer circuit 12, the timer circuit 12 operates and the logical value of the output signal S13 of the inverter 13 becomes "0". Then, as shown in FIG. 3, the timer circuit 12 sets the time T1 preset by the time setting circuit 9 from the rising of the vertical synchronizing signal / VSYNC.
When the counting of is finished, the logical value of the output signal of the inverter 13 becomes "1". Therefore, the logical value of the signal at the J terminal of the flip-flop 14 becomes "1". When the horizontal sync signal HSYNC separated by the sync separation circuit 6 is input to the C terminal of the flip-flop 14, the logical value of the signal from the Q1 terminal of the flip-flop 14 becomes “1”, and the flip-flop 15 outputs the logical value of “1”. J terminal and AND circuit 16
The logical value of the signal at one of the input terminals becomes "1". Therefore, the logical value of the signal at the / Q2 terminal of the flip-flop 15 is the horizontal synchronization signal HS separated by the synchronization separation circuit 6.
When YNC is input to the C terminal of the flip-flop 15, it changes from "1" to "0". Therefore, the AND circuit 16 outputs a gate signal having a pulse width corresponding to the horizontal scanning time T2, and the gate signal is input to the switch circuit 7.

The switch of the switch circuit 7 is normally switched to the switching terminal t1 side, and after the video signal from the image pickup camera 1 is amplified and shaped by the amplification and shaping circuit 5,
Although being input to the monitor 20 via the switch circuit 7 and the capacitor 19, the switch circuit 7 is switched to the switching terminal t2 side while the logical value of the output signal S16 of the AND circuit 16 is "1". As a result, as shown in FIG. 2, the distance mark signal 3 of the brightness set by the variable resistor 22 is displayed.
0 is displayed at the position of the distance L1 corresponding to the time T1 set by the time setting circuit 9. Then switch circuit 7
Is switched to the switching terminal t1 side, and the flip-flops 14 and 15 are reset every time the vertical synchronizing signal is output, and the same operation is repeated.

Therefore, the monitor 20 displays an image in which the distance mark signal 30 is superimposed on the video image taken by the image pickup camera 1. Regarding this distance mark signal 30, the distance mark signal 30 is matched with the model object position on the monitor 20 by arranging the model object at a desired distance in advance, for example, at a position 1 m from the bumper 31 of the vehicle and photographing it. As described above, the adjustment is performed by the time setting circuit 9, and the variable resistor 22 is also adjusted to the desired brightness. In this way, the image of the rear of the vehicle captured by the image capturing camera 1 is a video image captured by the image capturing camera 1, as shown in FIG.
When the motorcycle 33 is approaching the vehicle's bumper 31 to a distance of slightly more than 1 m, the distance can be quantitatively determined.

As described above, according to this embodiment, the monitor 2
In 0, the distance is set in advance by the time setting circuit 9 in the video image behind the vehicle taken by the imaging camera 1,
Since the image in which the distance mark signal 30 in which the brightness is adjusted to the desired value by the variable resistor 21 is superimposed is displayed, the rear of the vehicle is monitored on the monitor 20 in a state where the distance is accurately and quantitatively grasped. be able to.

Second Embodiment FIG. 4 is a system block diagram showing the configuration of the second embodiment of the surveillance camera system according to the present invention, and FIG. 5 is an explanatory diagram of the display on the monitor of the second embodiment. is there.

In the second embodiment, as shown in FIG. 4, two gate signal output circuits 8a and 8b are provided in comparison with the first embodiment already described with reference to FIG. Gate signal output circuits 8a and 8b are connected in parallel to the separation circuit 6, and the gate signal output circuits 8a and 8b are connected to each other.
Output terminals of the selector switches 32, t3, t4 of the selector switch 32.
And the common terminal t of the changeover switch 32.
5 is connected to the switch circuit 6. The configuration of the other parts of the second embodiment is the same as that of the first embodiment already described, and therefore a duplicate description will not be given.

In the second embodiment, the changeover switch 32 is changed over to the changeover terminal t3 side so that the gate signal output circuit 8a.
By using the time setting circuit 9 of the gate signal output circuit 8a.
The distance mark signal 30a of the distance set by is displayed on the monitor 20, the changeover switch 32 is changed over to the changeover terminal t4 side, the gate signal output circuit 8b is used, and the time setting circuit 9 of the gate signal output circuit 8b is used. By displaying the distance mark signal 30b of the set distance on the monitor 20, the monitor 20 displays an image in which the distance mark signals 30a and 30b are superimposed on the video image behind the vehicle captured by the imaging camera 1. It

According to the second embodiment, for example, the distance mark signal 30a indicating the distance of 1 m from the bumper of the vehicle.
And a distance mark signal 30b indicating a distance of 2 m from the bumper of the vehicle are displayed on the monitor 20 to monitor the rear of the vehicle on the monitor 20 in a state in which the distance is more accurately grasped as a binary value. Will be possible.

In the first embodiment, one gate signal output circuit is provided and one distance mark signal is displayed on the monitor. In the second embodiment, two gate signal output circuits are provided. The case where two distance mark signals are displayed on the monitor has been described, but the present invention is not limited to each embodiment, and a desired number of distance mark lines are displayed on the monitor according to the distance mark accuracy. It goes without saying that it is possible to do so.

[0024]

As described above, according to the present invention,
With a simple operation, it is possible to accurately check the distance from the vehicle or the like in which the surveillance camera is mounted in the displayed image, and drive safely.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a first embodiment of a surveillance camera system according to the present invention.

FIG. 2 is an explanatory diagram of a display on the monitor according to the first embodiment.

FIG. 3 is a time chart showing the operation of the first embodiment.

FIG. 4 is a block diagram showing the configuration of a second embodiment of the surveillance camera system according to the present invention.

FIG. 5 is an explanatory diagram of display on the monitor according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Imaging camera 5 ... Amplification shaping circuit 6 ... Sync separation circuit 7 ... Switch circuit 8, 8a, 8b ... Gate signal output circuit 9 ... Time setting circuit 12 ... Timer circuit 14, 15 ... Flip-flop 16 ... AND circuit 20 ... Monitor 21 ... Variable resistor 30, 30a, 30b ... Distance mark signal 32 Changeover switch

Claims (3)

[Claims] 1. An image pickup means, a sync separation means for separating a vertical sync signal and a horizontal sync signal from a video signal output from the image pickup means, and the vertical sync after a predetermined time from the input of the vertical sync signal. A gate signal output means for outputting a gate signal having a pulse width corresponding to one horizontal scanning time based on the signal and the horizontal synchronizing signal; and by outputting the gate signal, a distance mark signal is superimposed and displayed on the video signal. Camera system having a display means for performing the operation. 2. The surveillance camera system according to claim 1, further comprising adjusting means for adjusting the predetermined time of the gate signal output means. 3. The surveillance camera system according to claim 1, further comprising a brightness adjusting unit for adjusting the brightness of the distance mark signal displayed by the display unit.