JPH09259390A - Specified vehicle detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always image-pick up a vehicle video at optimum timing and to simplify an image processing while secrecy is improved by light-emitting a stroboscope in accordance with information from an image pickup timing detection device and image-picking up one image at every vehicle from the back of the vehicle to be detected with a video camera. SOLUTION: The image pickup timing detection device 24 is provided and the back of the vehicle 42 to be detected is image-picked up at optimum timing by one image on one vehicle. The detection timing device 24 transmits/receives an infrared pulse beam toward the front direction of travel on a road. A moment when the vehicle to be detected 42 passes a previously decided point, which can be detected by measuring the phase difference of the transmission/ reception optical pulses, is outputted as information. The detection information is inputted to a CCD camera 20 and the stroboscope 21 and the stroboscope emits light. The image at that time is image-picked up. Thus, the number of the image to be processed can be reduced. Image pickup and light emission can be executed once at every vehicle from the back and secrecy can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a specific vehicle detection device used for identifying an emergency dispatched vehicle or a stolen vehicle.

[0002]

2. Description of the Related Art A specific vehicle detection device of this type used for identifying an emergency dispatched vehicle or a stolen vehicle, etc., sequentially captures images of vehicles running on a road and reads out the number plate of the specific vehicle. However, since it is required to be mobile in order to identify an emergency dispatched vehicle, it must be a device that can be mounted on a vehicle and moved. Further, confidentiality is required for dispatched vehicles, stolen vehicles, etc. because it is necessary to prevent them from escaping.

FIG. 4 is a view for explaining a conventional specific vehicle detection device of this type. In the figure, reference numeral 40 is a detection vehicle having a specific vehicle detection device mounted at the rear portion thereof, and 41 is a detection vehicle stopped on the road shoulder. The imaging ranges 42a and 42b are detected vehicles running on a road to be detected. FIG. 5 is a diagram showing a part of the rear part of the detection vehicle 40. In the figure,
50 is a CCD camera, 51 is an infrared (IR) strobe,
52 is a strobe irradiation range, 53 is an image processing recognition device,
54 is a power supply device.

As shown in FIGS. 4 and 5, a conventional specific vehicle detection device of this type stops a detection vehicle 40 having a device mounted on the rear side thereof on a road shoulder and CCs through a rear window.
The D camera 50 and the strobe 51 are installed aiming at the rear of the traveling direction of the road, for example, the strobe 21 is made to emit light at intervals of 1/60 sec, and the panning of the image in front of the detected vehicle 42 is performed at this interval. That is, as shown in the operation step of FIG. 6, in step S61, images are continuously picked up at every 1/60 sec of the light emission interval of the strobe 21, and the captured images are sequentially sent to the image processing recognition device 53. At 53, a vehicle image is first extracted from each image using, for example, an algorithm that extracts only a moving image (step S62).

In the next step S63, the extracted individual vehicle images are enlarged to a certain size. That is, since the follow shots are taken at predetermined intervals in step S61, each image includes, for example, an image in which the vehicle has already passed and no vehicle image, an image in which the vehicle image is small, and a large image. Images including a plurality of vehicle images of different heights are mixed, and the vehicle number cannot be read properly as it is. Therefore, the vehicle extraction process and the size equalization process of the extracted vehicle image are performed,
In the next step 64, for example, the vehicle numbers (numbers and characters written on the number plate as well as the vehicle numbers described on the number plate are extracted from each vehicle image extracted using an algorithm for extracting only numbers and characters, for example. Read the concept including). Further, since the follow shots are taken at predetermined intervals in step S61 as described above, for example, when traffic is slow and the traveling speed of the vehicle is slow, images of one same vehicle are captured by a plurality of images. In some cases, a duplicate vehicle number is read out.
Therefore, in the next step S65, the overlapping numbers are unified into one, and it is verified whether or not the vehicle numbers sequentially read in the next step S66 are the numbers of the emergency dispatched vehicle or the stolen vehicle that have been input in advance. To do.

[0006]

As described above, the conventional specific vehicle detection device has a structure in which the IR strobe is continuously made to emit light and the front of the vehicle is taken at the intervals of this light emission while sequentially capturing images. Therefore, there is a problem that the driver of the vehicle is often noticed at the time of image capturing and the confidentiality is lacking.
As is well known, the IR strobe is accompanied by the emission of visible light such as near-infrared light, and because the vehicle position is scattered in order to perform follow shots, it is necessary to take an image with a wide angle of view and the strobe irradiation range. Also, as shown by 52 in FIG. 5, it is necessary to make it wide, so that the driver of the vehicle or the like will notice it by stroboscopic irradiation from the front of the vehicle. Therefore, in order to improve concealment, we have taken measures such as sticking a black film on the rear window, but even with this, there is a lot of chance to be noticed because the irradiation is from the front of the vehicle, and this black color is used when the detection vehicle is operating. The film interferes with rearward confirmation.

Further, since the conventional apparatus cannot follow the vehicle image at a proper timing as described above because of the follow shot at predetermined intervals, it is necessary to extract the vehicle image from each image. Therefore, it is necessary to align the size of the extracted vehicle image before reading the vehicle number, so software processing using a complicated algorithm is required, and the amount of software processing is large and the processing speed slows down. was there.

The present invention has been made in order to solve such a problem, and by constantly capturing the vehicle image at the optimum timing while improving the confidentiality, the specific vehicle in which the image processing can be greatly simplified. The purpose is to provide a detection device.

[0009]

A specific vehicle detection device according to the present invention is a vehicle to be detected when the vehicle to be detected passes a side of a vehicle for detection stopped on a road shoulder and reaches a predetermined point. In order to capture one image for each vehicle from the rear of the vehicle, an infrared (including near infrared ray and other rays) pulse beam is transmitted and received toward the front in the traveling direction on the road, and the phase difference between the transmitted and received pulses is measured. An imaging timing detection device that outputs, as information, the moment when the vehicle to be detected passes through the predetermined point that can be detected by doing so, in order to aim it forward in the traveling direction on the road through the side window, The means for installing the image pickup timing detection device, the infrared strobe and the video camera near the side window, and the information from the image pickup timing detection device By emitting an outside line strobe characterized by comprising means for performing imaging with the video camera.

Further, when the detection distance of the image pickup timing detection device is changed to change the predetermined point, means for automatically changing the irradiation angle of the infrared strobe and the angle of view of the video camera according to information from the image pickup timing detection device. It is characterized by having.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram for explaining an embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 4 denote the same parts, and 10 is a rear part thereof with a specific vehicle detection device according to the present embodiment. Detection vehicle parked on the shoulder, 11
Is the imaging range, and 12 is a detection beam for detecting the optimum imaging timing. FIG. 2 is a diagram showing a part of the rear portion of the detection vehicle 10, in which 20 is a CCD.
A camera, 21 is an infrared (IR) strobe, 22 is an image processing recognition device, 23 is a power supply device, and 24 is an imaging timing detection device which outputs the detection beam 12. Note that the image pickup timing detection device 24 does not have to be installed at the CCD camera 20 or the IR strobe 21 as shown in FIG. 2, but may be installed at the front end of the vehicle, for example.

The specific vehicle detection device according to this embodiment is
As shown in FIG. 1 and FIG. 2, one image per vehicle is captured behind the detection target vehicle 42 at an optimum timing. In general, when an image of a vehicle is taken and the vehicle number is read from an image, only an image that is hard to read can be taken by taking an image from the rear of the vehicle rather than an image from the front of the vehicle. For this reason, the specific vehicle detection device according to the present embodiment is provided with the image pickup timing detection device 24 for controlling the image pickup timing, and picks up one image per vehicle behind the detection target vehicle 42 at the optimum timing.

The basic principle of the imaging timing detecting device 24 is disclosed in detail in the patent application “moving object detecting device” filed on the same filing date as the present application, which is related to the same applicant as the present applicant. When a pulse beam (including the near infrared ray and other light rays) (detection beam 12 in FIG. 1 and FIG. 2) is transmitted and the reflected beam that hits the reflective object is received, the presence of the reflective object and the transmission / reception pulse Position of the reflecting object due to phase difference (distance to the reflecting object)
It is configured so that information can be obtained. Therefore, when the reflecting object is a moving body such as a vehicle, the desired position (distance)
By setting the detection level corresponding to the distance to, it is possible to output the timing of the moment when the moving body passes through this point, and the detection accuracy is high because the detection using the reflected light intensity is not performed. The feature is that the degree of freedom of setting the detection range and the installation location is high.

Next, the operation of this embodiment will be described with reference to the operation steps of FIG. As described above, when the imaging timing detection device 24 detects the passage of a vehicle at a predetermined detection point (step S31), this detection information is stored in the CCD.
It is input to the camera 20 and strobe 21, and strobe 2
1 emits light, and an image at that time is captured (step S3).
2). Since the apparatus of the present embodiment captures an image at the moment when the vehicle passes through the predetermined detection point in this way, one image is captured for each vehicle, and compared to the conventional apparatus that performs follow shot processing. The number of images to be processed can be reduced.
Further, the image pickup and the strobe light emission may be performed once for each vehicle from the rear of the detection vehicle 42, and since the image pickup position can be set at the optimum timing position, the angle of view and the stroboscopic irradiation range can be narrowed, and the vehicle can be emitted. The risk of being noticed by the driver or the like is reduced, and the confidentiality can be improved.

At the next step S33, the vehicle number is immediately read from the captured image, and at the next step S34.
Then, it is checked whether or not the vehicle numbers sequentially read are the numbers of the emergency dispatched vehicle or the stolen vehicle which have been input in advance. That is, since the angle of view is narrow and the vehicle image magnification in the image is the same, and the number plates of general vehicles other than light vehicles, motorcycles, etc. are the same, processing operations such as vehicle image enlargement become unnecessary, Moreover, since the same vehicle is not captured in a plurality of images, the vehicle number can be read out as it is. As a result, the processing steps S62 and S63 shown in FIG.
And S65 can be omitted, the processing speed can be improved, and a complicated algorithm such as appropriately extracting only vehicle images of different sizes from the images required by the conventional device is used. There is no need to perform image processing.

It is needless to say that the detection level of the image pickup timing detection device 24 can be changed to set the image pickup timing at another position (distance), and in this case, the angle of view of the CCD camera 20 and the strobe light can be set. It is necessary to change the irradiation angle of 21, but in this case, a device that automatically performs zooming in conjunction with a change in the detection level of the imaging timing detection device 24 may be used.

[0017]

As described above, the specific vehicle detection device of the present invention can detect the specific vehicle by always capturing the vehicle image at the optimum timing while improving the confidentiality, and the image processing operation steps and necessary This has the effect of greatly simplifying the software.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an embodiment of the present invention.

FIG. 2 is a diagram for explaining a device configuration example of the present embodiment.

FIG. 3 is a diagram for explaining operation steps of the present embodiment.

FIG. 4 is a diagram for explaining a conventional device of this type.

FIG. 5 is a diagram for explaining a configuration example of a conventional device.

FIG. 6 is a diagram for explaining operation steps of a conventional device.

[Explanation of symbols]

 10 Detection Vehicle 11 Imaging Range 12 Detection Beam 20 CCD Camera 21 Infrared (IR) Strobe 22 Image Processing Recognition Device 23 Power Supply Device 24 Imaging Timing Detection Device 42 Detected Vehicle

Claims (2)

[Claims] 1. An infrared strobe and a video camera for picking up an image of a traveling vehicle (hereinafter referred to as a detected vehicle) so as not to be noticed by a driver or the like of the vehicle,
A device comprising an image processing recognition device for performing image processing of the captured image to recognize numbers and characters written on the number plate of the vehicle to be detected and collating with numbers and characters that have been input in advance. In the specific vehicle detection device mounted on the detection vehicle, when the detection vehicle passes by the detection vehicle stopped on the road shoulder and reaches a predetermined point, one vehicle from the rear of the detection vehicle is detected. In order to capture one image for each, it can be detected by sending and receiving infrared (including near infrared and other rays) pulse beam toward the front in the traveling direction on the road and measuring the phase difference between the sending and receiving pulses. An imaging timing detection device that outputs, as information, the moment when the vehicle to be detected passes through the above-mentioned predetermined point, in order to aim at the front in the traveling direction on the road through the side window, Means for installing the imaging timing detection device, the infrared strobe, and a video camera near the side window of the detection vehicle; means for causing the infrared strobe to emit light in accordance with information from the imaging timing detection device to perform imaging with the video camera; A specific vehicle detection device comprising: 2. When the detection distance of the image pickup timing detection device is changed to change the predetermined point, the irradiation angle of the infrared strobe and the angle of view of the video camera are automatically calculated based on information from the image pickup timing detection device. The specific vehicle detection device according to claim 1, further comprising: a changing unit.