JP2013025583A - Vehicle monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle monitoring device allowing easy installation of the vehicle monitoring device and easy positioning adjustment after the installation.SOLUTION: The vehicle monitoring device photographing a traveling vehicle by a monitoring camera and analyzing the photographed image to acquire a registration number or vehicle color of the vehicle comprises an image processing device including: an inclination detection section for detecting an edge of the image and detecting inclination of the monitoring camera from inclination of the edge; and a visual field width detection section for recognizing a width of a number plate in the image and detecting a visual field width of the camera on the basis of the recognized width and a width of the image. The image processing device includes a determination section for determining the inclination of the monitoring camera and propriety of an interval between the camera and a monitoring object vehicle position on the basis of the detected inclination of the monitoring camera and the visual field width and displaying information to instruct the adjustment direction on a display device when the determination is no.

Description

  The present invention relates to a vehicle monitoring device, and more particularly, to a vehicle monitoring device including means for assisting adjustment of a monitoring camera constituting the vehicle monitoring device.

  The vehicle monitoring device is used for the purpose of capturing a moving vehicle with a monitoring camera, analyzing the captured image, and acquiring characteristic data such as the shape, vehicle color, and registration number of the vehicle. For this reason, the vehicle monitoring device is installed at a predetermined point for a certain period of time, captures the vehicle traveling by the monitoring camera, displays the captured video on the monitor, or performs image processing on the captured video to acquire the feature data. Or recording.

  In recent years, there has been an increasing need for temporarily monitoring the vehicle, changing the installation point in a short period of about one day to one week, and monitoring the vehicle again.

  There are various installation conditions for the vehicle monitoring device. Further, when changing the installation location of the vehicle monitoring device, it is necessary for the monitoring camera to adjust the angle of view and the like so that an appropriate captured image can be obtained each time. For this adjustment, a simple adjustment method is desired.

  Patent Document 1 discloses a technique for automatically adjusting the focus of a monitoring camera in a vehicle monitoring apparatus to an optimum value.

JP 2006-235922 A

  According to the prior art, it is possible to pick up an image of a running car, automatically adjust the focus based on the picked up image, and recognize the car number. However, the technique is based on a vehicle monitoring device that is fixedly arranged at a predetermined position. For this reason, when the vehicle monitoring apparatus is moved to a necessary place and installed and adjusted as necessary, adjustment work is complicated, and skill is required for appropriate adjustment.

  The present invention has been made in view of these problems, and provides a vehicle monitoring apparatus that can easily perform installation of the vehicle monitoring apparatus and position adjustment after installation.

  In order to solve the above problems, the present invention employs the following means.

  In a vehicle monitoring device that captures a traveling vehicle with a monitoring camera and analyzes the captured image to obtain a registration number or a vehicle color of the vehicle, an edge of the image is detected, and an inclination of the monitoring camera is detected from the inclination of the edge. An image including an inclination detection unit for detecting an inclination and a visual field width detection unit for recognizing the width of the license plate in the image and detecting the visual field width of the camera based on the recognized width and the width of the image A processing device, and the image processing device determines whether or not the tilt of the monitoring camera and the interval between the camera and the monitoring target vehicle position are appropriate based on the detected tilt and field of view of the monitoring camera. And a determination unit for displaying information indicating the adjustment direction on the display device.

  Since this invention is provided with the above structure, the position of a vehicle monitoring apparatus and position adjustment after installation can be simply performed.

It is a figure explaining the composition of the vehicle monitoring device concerning a 1st embodiment. It is a figure explaining the use condition of a surveillance camera. It is a figure which shows the image image | photographed with the surveillance camera. It is a figure explaining the process of a picked-up image determination part. It is a figure which shows the example of the monitoring camera image displayed on a display part. It is a figure explaining 2nd Embodiment. It is a figure which shows the example at the time of performing increase / decrease in an electric current value according to the distance to a vehicle, and the increase / decrease amount of the electric current value supplied to an illuminating device.

  Hereinafter, embodiments will be described with reference to the accompanying drawings. FIG. 1 is a diagram illustrating the configuration of a vehicle monitoring apparatus according to an embodiment of the present invention. As shown in FIG. 1, the vehicle monitoring device includes a monitoring camera 1, an image processing device 2, and a display unit 3. The monitoring camera 1 includes an illumination device 11, an illumination control device 12 that controls the light emission amount of the illumination device, and a camera 13. The image processing apparatus 2 includes an image processing unit 21 and a captured video determination unit 22.

  FIG. 2 is a diagram for explaining a use state of the monitoring camera. As shown in FIG. 2, the monitoring camera 1 is located at a position 5 to 20 m away from the vehicle 4 to be monitored, from the front, side or top surface of the vehicle. Shoot.

  The video signal captured by the monitoring camera 1 is transmitted to the image processing unit 21. The image processing unit 21 performs image processing such as contrast adjustment and edge enhancement on the captured video, and then transmits the image to the captured image determination unit 22. The captured image determination unit 22 extracts feature data such as the shape of the vehicle 4, the vehicle color, and the registration number from the video signal, and transmits the extracted data to the display unit 3. For example, the display unit 3 displays the video data in addition to the feature data.

  FIG. 3 shows an image taken by the surveillance camera. In FIG. 3, a processing area 51 is located in the center of the screen and is an area to be photographed regardless of the installation conditions, and it is desirable that the license plate 41 enters this area. Assuming that the video 5 taken by the surveillance camera is taken and analyzed, it is preferable that the vehicle 4 is stopped during photography for camera position adjustment. You may do it.

  FIG. 4 is a flowchart for explaining the processing of the captured video determination unit 22. In FIG. 4, first, the image processing unit 21 detects the vehicle 4 by processing the monitoring camera video (step S221). When the vehicle is detected, the license plate portion (the license plate itself, its inclination, and the written character portion) is extracted from the area where the vehicle is detected (step S222). Next, the characters written on the license plate are recognized (step S223). It is determined whether or not the character recognition is successful. If “No”, the inclination of the license plate is measured (step S224). If the character recognition is successful, it is determined that there is no abnormality in the inclination and the visual field width.

  When measuring the inclination, the moving direction of the vehicle 4 or the vertical and horizontal edges of the image in the processing area 51, for example, the vertical and horizontal edges of the license plate are extracted, and the monitoring camera 1 is extracted from the extracted edge inclination. Is measured (step S224). Next, the license plate 41 of the vehicle 4 is recognized, and the visual field width is measured from the recognized license plate size (percentage in the image size) (step S225). Next, based on the measurement result of the tilt and the measurement result of the visual field width, it is determined whether or not the imaging region is appropriate (step S226), and if abnormal, the abnormality is reported on the display unit 3. (Step S227).

  FIG. 5 is a diagram illustrating an example in which guide information for adjusting the attachment position is added to a captured image captured by the surveillance camera. As shown in FIG. 5, the video imaged by the surveillance camera 1 is displayed on the display unit 3. In addition, when an abnormality is determined by the photographed image determination unit 22, a warning indicating an abnormality is displayed, and a position adjustment method for avoiding the abnormality is displayed.

  For this reason, the operator who installs the surveillance camera may adjust according to the displayed adjustment method, and can easily and quickly complete the attachment work and the adjustment work of the attachment position. The photographed image determination unit 22 displays the adjustment method even during the adjustment, and when the displayed adjustment is completed, the abnormality warning and the adjustment method are not displayed to confirm that the adjustment has been completed normally. Can be able to.

  FIG. 6 is a diagram for explaining a second embodiment of the present invention. As shown in FIG. 6, the vehicle monitoring device includes a monitoring camera 1, an image processing device 2, and a display unit 3. The monitoring camera 1 includes a lighting device 11, a lighting control device 12 that controls the amount of light emitted from the lighting device 11, a camera 13, and a distance measuring device 14 such as an ultrasonic distance meter that measures the distance from the monitoring target vehicle 4. . In addition, the image processing apparatus 2 includes an image processing unit 21 and a captured video determination unit 22. In the figure, the same parts as those shown in FIG.

  Compared with the vehicle monitoring device of the first embodiment, the vehicle monitoring device of this embodiment is provided with a distance measuring device 14 for measuring the distance between the monitoring camera 1 and the vehicle 4.

The distance measuring device 14 measures the distance L from the vehicle 4 using an ultrasonic distance meter or the like, and the illumination control device 12 is expressed by the following equation (1).
P = V * I (I = f (L)) (1)
That is, the power P supplied to the lighting device is adjusted according to the distance L to the vehicle, and the light emission amount is adjusted.

  Expression (1) is an expression for controlling the current I flowing through the lighting device 11 according to the distance from the vehicle 4 by the lighting control unit 12. Based on the set value L = 15 m, control is performed such that a large amount of power is supplied if the vehicle position is farther than that, and a small amount of power is supplied if the vehicle position is close. In this way, by adjusting the light emission amount of the illumination device 11, the vehicle can always be illuminated with brightness suitable for image processing even if the distance from the vehicle 4 is different.

  FIG. 7 is a diagram illustrating an example of the distance L = 15 ± X and the current I supplied to the lighting device when the current value is increased or decreased according to the distance. The reference distance L and the current I supplied to the lighting device at that time are determined, and control is performed so that the difference X between the reference distance and the actual distance is reflected in the current I.

  The vehicle 4 can be photographed under appropriate photographing conditions even if the distance is different by feeding back the measurement result from the distance measuring device 14 to the camera 1 and performing zoom adjustment and focus adjustment of the camera 1.

  As described above, according to the embodiment of the present invention, the subject can be arranged at an appropriate position in consideration of the image processing of the surveillance camera. In addition, even when the distance between the monitoring camera and the subject changes with respect to the installation conditions, it is possible to obtain a captured image with appropriate brightness. For this reason, recognition errors by the image processing apparatus can be suppressed.

DESCRIPTION OF SYMBOLS 1 Surveillance camera 2 Image processing apparatus 3 Display part 4 Vehicle 5 Photographed image 11 Illumination apparatus 12 Illumination control part 13 Camera 14 Distance measuring device 21 Image processing part 22 Photographed image determination part 41 Number plate 51 Processing area

Claims (3)

In a vehicle monitoring device that captures a traveling vehicle with a monitoring camera, analyzes the captured image, and acquires a registration number or a vehicle color of the vehicle,
An inclination detection unit that detects an edge of the image and detects an inclination of the monitoring camera from an inclination of the edge;
Recognizing the width of the license plate in the image, and comprising an image processing device comprising a visual field width detection unit for detecting the visual field width of the camera based on the recognized width and the width of the image;
The image processing apparatus determines whether or not the tilt of the monitoring camera and the interval between the camera and the monitoring target vehicle position are appropriate based on the detected tilt and field of view of the monitoring camera. A vehicle monitoring device comprising: a determination unit that displays information indicating the above on a display device. The vehicle monitoring device according to claim 1,
A distance measuring device that measures the distance from the vehicle position to be imaged, a lighting device that illuminates the vehicle position that is the subject, and a control device that controls the amount of light emitted from the lighting device;
A vehicle monitoring device that controls an irradiation light amount of an illumination device based on a measurement result of the distance measuring device. The vehicle monitoring device according to claim 1,
It has a distance measuring device that measures the distance to the vehicle to be photographed,
The image processing device adjusts zoom and focus of a camera based on a measurement result of the distance measuring device.

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