JP4400258B2 - Height limit excess detection device - Google Patents

Description

  The present invention relates to an apparatus for detecting an approaching vehicle or the like exceeding a restricted height at a place where the height is restricted on a road or a passage. In particular, the present invention relates to an over-height limit detection device that detects a vehicle 2 passing through a location corresponding to the restricted height in the video by installing an ITV camera at a location in front of the height-limited location and processing the video. is there.

There are restrictions on the height of traveling vehicles on the roads and passages under the overpass and under the guard.
If a merchant vehicle enters here and collides with a crossover or guard from a height limit, a serious accident will occur, and various measures are taken to prevent this.
For example, a structure such as a robust gate or signboard equivalent to the restricted height is installed in front of the restricted height C, and even in the worst case, the approaching vehicle interferes with the structure and stops so that the overpass or guard Collision with the body of the.
Furthermore, in addition to physically blocking the intruding vehicle, a sensor for detecting an excessive height limit is installed at a point in front of the height restriction point C to detect the approaching vehicle and issue a warning to the driver. In order to prevent the vehicle from entering the underpass or under the guard.

In Patent Document 1, an ultrasonic sensor is installed above a point in front of the height restriction point C, and the height of the vehicle passing below is measured to detect whether or not the restriction height is exceeded. A device is described that prevents entry into the height-restricted portion C by displaying an alarm at an alarm unit installed near the height-restricted portion C when an excess is detected.
This method (hereinafter referred to as an ultrasonic sensor method) has a transmitter and a receiver in one ultrasonic sensor, emits ultrasonic waves from the transmitter, receives ultrasonic waves reflected by the object, and receives the time difference between them. Is a device that measures the distance from the object to the object. In Patent Document 1, a plurality of these are installed above the passage, and the height of the vehicle passing through the lower part is measured to detect the vehicle exceeding the limit height. .

Patent Document 2 describes a device that includes a sensor that detects the height of a moving object such as a vehicle and a warning device, and that issues a warning to the driver using the warning device when the moving body exceeds the limit height. ing.
Here, the height of the moving body is detected by installing a transmission type height detection sensor on two pillars installed at positions sandwiching the passage.
This method (hereinafter referred to as “transmission optical sensor method”) has pillars on both sides of the road in front of the height restriction point, a light emitter is installed at the restricted height position of one pillar, and the restricted height of the other pillar. In this position, a light receiver is installed to receive the light beam of the light emitter, and when the moving body blocks this light beam, this is detected to detect the moving body exceeding the limit height.

In Patent Document 3, two cameras are installed on the side of the road in front of the height-restricted portion C, and the three-dimensional measurement of the edge in the width direction of the passing vehicle is performed to measure the height of the vehicle and to limit the height. A system for outputting predetermined warning information for vehicles exceeding is described.
This system (hereinafter referred to as a system using two cameras) is installed on one pillar on the side of the road in front of the height-restricted point C at a position where the two cameras are looked down diagonally from above. The edge in the width direction of the vehicle that passes through the observation area is extracted, and the height of the vehicle is measured by measuring the height of the vehicle by performing three-dimensional measurement of the feature point of the vehicle using the corresponding edge coordinates between the images. It detects the vehicle exceeding
The present invention relates to these applications, and relates to an apparatus that is an alternative to a sensor that detects an excessive height limit.
Japanese Patent Application Laid-Open No. 7-26522 “Height Limit Excess Detection / Alarm Device 30” Registered Utility Model No. 3039909 “Warning Device Exceeding Restricted Height of Vehicles” JP-A-11-175880 "Vehicle height measuring device and vehicle monitoring system using this device" JP2002-034808 JP 2002-150294 A References: “Image Processing Handbook” edited by Morio Onoe, Shosodo, 1989

1] Ultrasonic sensor system It is necessary to install a structure higher than the limit height in order to install it above the road.
The installation cost of the structure where the sensor is installed is high, and it is necessary to block traffic during the installation work.
The ultrasonic wave has a certain directivity, and the detection range of the ultrasonic sensor is about one vehicle.
Multiple sensors are required to detect a wide range of height-limited vehicles such as multiple lanes.
This cannot be detected when only part of the vehicle exceeds the limit height (such as the tip of a crane).

2] Light transmission type sensor system It is necessary to install two pillars for the light emitter and the light receiver.
Installation adjustment is difficult because the optical axes of the light emitter and the light receiver need to be exactly aligned.
When light emitters and light receivers are installed on both sides of the road, only the entering vehicle cannot be detected.
When the light emitter and the light receiver are separated, the light spreads and thin objects such as the tip of a crane cannot be detected.

3] Method using two cameras It is necessary to know the positions and postures of the two cameras accurately for three-dimensional measurement, and installation adjustment is difficult.
Adjustment is difficult because the focal length, aperture, focus and synchronization of the two cameras need to be the same.
Since horizontal edges in the image are used, vertical projections such as the tip of a crane cannot be detected.

  A height limit excess detection device according to claim 1 of the present invention that solves the above-mentioned problems is the height of an approaching vehicle or the like that is installed at a point in front of a height restriction point on a road or a passage and exceeds the limit height. In an over-height limit detection device that detects an over-limit object, the apparatus includes an ITV camera and an image processing unit, and the camera has a limit height such as a roadside pillar at a point in front of the road or passage height restriction point. At the same height position, with the road direction facing the optical axis horizontally and perpendicular to the road, the image processing unit inputs the video signal of the camera, and reaches the limit height in the input image A change detection process of the window portion set in the peripheral portion of the corresponding region is performed, and when a change is detected in the window, “exceeding the height limit” is detected and output.

  The height limit excess detection device according to claim 2 of the present invention that solves the above problem is installed at a point in front of a height restriction point on a road or a passage and enters an entry object such as an approaching vehicle that exceeds the limit height. In the height limit excess detection device for detecting a road, it is composed of an ITV camera, an image processing unit, and an image recording unit. The optical processing unit is installed at a position at the same height as the road with the optical axis oriented horizontally and perpendicular to the road, and the image processing unit inputs the video signal of the camera, and the restricted height in the input image A change detection process of the window portion set in the peripheral portion of the area corresponding to the height is performed, and when a change is detected in the window, the presence of “exceeding the height limit” is detected and output. Image at the time of over-limit vehicle detection or before and after Characterized by saving the image.

  According to a third aspect of the present invention, there is provided a height limit excess detection device according to a third aspect of the present invention, wherein the image processing unit inputs a video signal of the camera. Then, the change detection process of the window part set in the peripheral part of the area corresponding to the limit height in the input image is performed, and when the change is detected in the window, the changed area is combined, Calculate geometric features such as area, perimeter, aspect ratio, etc., and detect and output `` exceeding height limit object '' when these calculated values are within the range corresponding to the preset detection target It is characterized by doing.

  According to a fourth aspect of the present invention for solving the above-mentioned problem, the height limit excess detecting device according to the third aspect is the height limit excess detecting device according to the third aspect, wherein the image processing unit inputs a video signal of the camera, When the change detection processing of the window part set in the peripheral part of the area corresponding to the limit height in the inside is performed, and the change is detected in the window, the changed area is combined, and the area and the peripheral length of the area are combined. And geometric features such as aspect ratio are calculated, and when these calculated values are within the range corresponding to the preset detection object, change detection processing is further performed using the entire input image as the target area. The area of the target area including the area that has changed inside the window, the geometric feature amount such as the perimeter and aspect ratio are calculated, and these calculated values are applied to the preset detection target. When within the corresponding range, And outputting by detecting the Limited exceeded object ".

  According to a fifth aspect of the present invention for solving the above-mentioned problem, the height limit excess detecting device according to the first aspect is the height limit excess detecting device according to the first aspect, wherein the image processing unit inputs a video signal of the camera, Set two windows in the horizontal direction at the periphery of the area corresponding to the restricted height in the middle, and perform change detection processing for each of the two set windows, and change in the window farther from the restricted height. When a change is detected in a window closer to the height limit portion after a certain time after detection, “the presence of an object that exceeds the height limit” is detected and output.

  According to a sixth aspect of the present invention for solving the above-described problem, the height limit excess detecting device according to the first or second aspect is the above-described height limit excess detecting device, wherein the image processing unit inputs a video signal of the camera. Then, the change detection processing of the window portion set in the peripheral portion of the area corresponding to the limit height in the input image is performed, and when the change is detected in the window, the movement direction of the changed area is calculated, When the calculated movement direction is a direction approaching a height-restricted location, “height limit exceeding object intrusion” is detected and output.

  The height limit excess detection device according to claim 7 of the present invention for solving the above-described problem is characterized in that the change detection process in the window in the image processing unit of claim 1, 2, 3, 4, 5 or 6 The image is divided into appropriate small areas, and the correlation value between the background image acquired in advance for each small area and the corresponding small area image in the current video is calculated. When a small change area in the window is detected, “exceeding the height limit” is detected and output.

  The height limit excess detection device according to claim 8 of the present invention for solving the above problem is the height limit excess detection device according to claim 1, wherein the image processing unit inputs a video signal of the camera, A plurality of windows are set around the area corresponding to the limit height in the middle, change detection processing of each set window portion is individually performed, and when a change is detected in the window, each window “ A different alarm corresponding to “exceeding height limit” is output.

  A height limit excess detection device according to claim 9 of the present invention that solves the above-described problem is the height of an approaching vehicle or the like that is installed at a point in front of a height limit point on a road or a passage and exceeds the limit height. In an over-height limit detection device that detects an over-limit object, it is composed of an ITV camera and an image processing unit, and the camera restricts a roadside pillar in the vicinity of or near the height-restricted portion of the road or passage. Installed at the same height as the optical axis in the horizontal direction toward the vehicle approach direction of the road, the image processing unit inputs the video signal of the camera and corresponds to the limit height in the input image A change detection process of the window portion set in the periphery of the area to be performed is performed, and when a change is detected in the window, “exceeding the height limit” is detected and output.

  A height limit excess detection device according to claim 10 of the present invention that solves the above-described problems is the height of an approaching vehicle or the like that is installed at a point in front of a height restriction point on a road or a passage and exceeds the limit height. In an over-height limit detection device that detects an over-limit object, it is composed of an ITV camera, an image processing unit, and an image recording unit. The optical processing unit is installed at a position having the same height as the restricted height of the camera, with the optical axis oriented horizontally and in the direction of the restricted height, and the image processing unit inputs the video signal of the camera, and the restricted height in the input image A change detection process of the window portion set in the peripheral portion of the area corresponding to the height is performed, and when a change is detected in the window, the presence of “exceeding the height limit” is detected and output. Image at the time of over-limit vehicle detection or before and after Characterized by saving the image.

  A height limit excess detection device according to an eleventh aspect of the present invention that solves the above-described problems is the height of an approaching vehicle or the like that is installed at a point in front of a height limit location on a road or a passage and exceeds the limit height. In the height limit excess detection device that detects an object that exceeds the limit, it is composed of two ITV cameras, an image processing unit, and an image recording unit that are installed on the opposite side to the front side in the direction of travel of the height limit point. The camera is installed at the same height as the restricted height of the eaves on the road near the height restriction location, with the optical axis oriented horizontally and in the direction of the height restriction location, Install the optical axis horizontally and in the direction of the height-restricted part at the same height as the restricted height of the pillars on the side of the road, etc. The image processing unit individually inputs the video signal of the camera and limits the input image. A change detection process of the window portion set in the periphery of the area corresponding to the height is individually performed, and when the change is detected in the window, the presence of “exceeding the height limit” is detected and output, and the image recording The unit stores the images of the two cameras at the time of detecting the vehicle exceeding the height limit or the images before and after the images.

  A height limit excess detection device according to claim 12 of the present invention that solves the above-described problems is the height of an approaching vehicle or the like that is installed at a point in front of a height restriction point on a road or a passage and exceeds the limit height. In an over-height limit detection device that detects an over-limit object, it is composed of an ITV camera and an image processing unit, and the camera has a lens center on a pillar on the side of the road in front of the road or passage height restriction point. At the same height as the limit height, the optical axis is set in the direction perpendicular to the road and the area around the limit height is imaged downward, and the image processing unit inputs the video signal of the camera Then, change detection processing of the window part set in the peripheral part of the area corresponding to the limit height in the input image is performed, and when a change is detected in the window, “exceeding the height limit” is detected and output. It is characterized by that.

The present invention relates to an apparatus that detects an approaching vehicle or the like that is installed at a point in front of a road or passage height restriction point C and that exceeds the restriction height, and has the following effects.
(1) It is possible to detect in advance a vehicle that is about to enter a height-restricted location.
(2) Vehicles that exceed the height limit across the front of the camera can be detected correctly over a wide range.
(3) Installation of the equipment is easy and there is no need to block traffic during installation work.
(4) Correct detection is possible even when only a part of the vehicle exceeds the limit height.
(5) Installation adjustment and maintenance are easy.
(6) Longitudinal protrusions can be detected correctly.

  The modes described as the following Examples 1 to 12 are the best modes for carrying out the present invention.

A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows a camera installation position of a height limit excess detection device according to the present invention, and is a schematic view of an approach direction of a vehicle 2 having a crane 2a from a height limit point C. FIG. 2 is a configuration diagram of the height limit excess detection device according to the present embodiment. FIG. 3 is an image example of the camera 10 of FIG. 1, and the vehicle 2 exceeding the limit height A indicated by the broken line in the drawing can be seen.
This embodiment is based on the basic concept of the present invention, and is an apparatus for detecting an approaching vehicle 2 or the like that is installed at a point in front of a height restriction point C on a road or a passage and that exceeds the restriction height. It is.

That is, the height limit excess detection device according to the present embodiment includes the ITV camera 10 and the image processing unit 20.
The ITV camera 10 is installed at the same height as the restricted height A of the roadside pillar 1 etc. at a point in front of the restricted height C of the road or passage. The optical axis is set to a direction that is horizontal and orthogonal to the road with the road direction.
The image processing unit 20 inputs a video signal of the ITV camera 10 (image input unit 21), sets a window B in the peripheral portion of the area corresponding to the restricted height A in the input image (window processing unit 22), A change detection process in the set window B is performed (change detection means 23), and when a change is detected in the window B, the “height limit excess” is detected and output to the alarm device 30 (detection output means) 24).

The camera 10 is horizontally installed at the same height as the limit height A of the pillar 1 on the roadside.
In this embodiment, as shown in FIG. 3, a window B is set near the limit height A, and when a change is detected inside the window B, “exceeding the height limit” is detected.
The change detection process in the window B can be realized by a time difference process.
For example, it is possible to temporarily store an image in window B of the previous video, compare it with window B of the current video, and detect a change when there is a different part.
Further, the change detection process in the window B can be performed by a background difference process.
That is, it is also possible to obtain an image without the approaching vehicle 2 as a background image in advance and detect that there is a change when the window B of the current video is different from the window B of the background image.

As described above, according to the first embodiment based on the basic concept of the present invention, the following effects can be obtained.
(1) Since the camera 10 is installed in front of the height-restricted portion C to detect that the height limit has been exceeded, it is possible to detect in advance the vehicle 2 that is about to enter the height-restricted portion C. Based on this, it is possible to take measures such as issuing a warning to the driver.
(2) Whereas the method using an ultrasonic sensor or a light transmission type sensor detects at one point of the sensor installation position, the apparatus of the present invention restricts by observing the entry path of the vehicle 2 from the lateral direction. Since the change in the image of the window B set in the vicinity of the height A is detected and output, it is possible to correctly detect the vehicle over the height limit 2 that crosses the front of the camera 10 over a wide range.
(3) In the method using an ultrasonic sensor, it is necessary to install a gate on the road and install an ultrasonic sensor downward on the top. In the case of a light transmission type sensor, two pillars 1 sandwiching the road are required. On the other hand, in the apparatus of the present invention, since the ITV camera 10 is installed on one pillar 1 on the side of the road, it is possible to detect the height limit excess, so that the apparatus can be easily installed and traffic is prevented during the installation work. There is no need to shut off.

(4) When the distance between the light emitter and the light receiver is far apart with an ultrasonic sensor or a light transmission sensor, the detection range has a certain spread, so only the tip of the crane 2a exceeds the limit height A However, in the apparatus of the present invention, when any moving object is detected in the window B, the limit height A is detected, so that only a part of the vehicle 2 is limited. Even when the height A is exceeded, correct detection is possible.
(5) Installation and adjustment of the light-transmitting sensor is difficult because it is necessary to accurately align the optical axes of the light emitter and the light receiver. However, in the apparatus of the present invention, the camera 10 can be easily installed and adjusted by installing it horizontally. Is completed.
(6) The method of using two cameras 10 requires adjustment to make the focal lengths and diaphragms of both cameras 10 the same, and the installation adjustment is complicated. Since only one unit is used, adjustment is relatively easy.
(7) The method of performing stereo measurement by extracting the horizontal edge in the image cannot detect vertical protrusions such as the tip of the crane 2a. Since the part which moves in the window B is detected by observing from above, the vertical projection can be detected correctly.

Note that the window B set in the present invention may be a rectangular area, a line, a point, or any shape as long as it is set in an area corresponding to the limit height A, and the same effect can be obtained.
However, an area in which the vehicle 2 lower than the limit height A is not erroneously detected must be set.
In addition, the height limit excess detection device of the present invention can also implement the image input means and below with computer software.
This is the same in all the embodiments described below.

A second embodiment of the present invention is shown in FIG. FIG. 4 is a configuration diagram illustrating the height limit excess detection device according to the second embodiment.
The present embodiment is improved so as to record a video image at the time of detection.
In other words, the second embodiment includes the ITV camera 10, the image processing unit 20, and the image recording unit 40.
The ITV camera 10 is installed at the same height as the restricted height A of the roadside pillar 1 etc. at a point in front of the restricted height C of the road or passage. The optical axis is set to a direction that is horizontal and orthogonal to the road with the road direction.

The image processing unit 20 inputs a video signal of the ITV camera 10 (image input unit 21), sets a window B in the peripheral portion of the area corresponding to the restricted height A in the input image (window processing unit 22), A change detection process in the set window B is performed (change detection means 23), and when a change is detected in the window B, the “height limit excess” is detected and output to the alarm device 30 (detection output means) 24).
The image recording unit 40 stores an image at the time of detecting a vehicle exceeding the height limit or images before and after the image.
Thereby, it becomes possible for the operator to visually check the situation at that time by looking at the image when the height limit excess detection stored in the image recording unit 40 or the images before and after the image.

For example, what is the vehicle 2 about to enter, whether a large vehicle 2 exceeding the limit height A is about to enter, or whether a part of the vehicle 2 exceeds the limit height A like a crane car, etc. There is an advantage that information relating to the identification of the approaching vehicle 2 can be obtained.
For example, when the vehicle 2 ignores the warning and enters the height-restricted portion C and damages a structure such as a bridge, a guard, or an overhead wire, it is important information that provides evidence for identifying the vehicle 2. .

As described above, the second embodiment that records the image at the time of detection has the following effects.
(1) In addition to the effects of the first embodiment, it becomes possible for the operator to visually check the situation at the time when the operator sees the image at the time of the height limit excess detection or the images before and after the image.
(2) There is an advantage that information regarding the identification of the approaching vehicle 2 can be obtained. For example, when the vehicle 2 ignores the warning and enters the height-restricted portion C and damages a structure such as a bridge, a guard, or an overhead wire, it is important information that provides evidence for identifying the vehicle 2. .

A third embodiment of the present invention is shown in FIG. As shown in FIG. 5, the present embodiment relates to labeling in the window B, and the change area in the window B is extracted as a lump.
That is, in the height limit excess detection device according to the first embodiment or the second embodiment, the image processing unit 20 inputs the video signal of the ITV camera 10 and puts it in the peripheral portion of the region corresponding to the limit height A in the input image. When the change detection process in the set window B is performed and a change is detected in the window B, the changed areas are combined, in other words, the changed area in the window B is extracted as a lump, and the area ( Calculate the geometric features such as the area of the lump), the perimeter, and the aspect ratio, and when these calculated values are within the range corresponding to the preset detection target, Detect and output to alarm device 30 or the like.

In the first embodiment, when a minute change is detected in the window B, for example, when there is a minute disturbance of the image due to image noise or when a small object such as a leaf or bird crosses the front of the camera 10, there is no entering vehicle 2. Nevertheless, there was a possibility of output with the height limit exceeded.
On the other hand, according to the present embodiment, by evaluating the size or the like of the moving area in the window B, it is possible to reliably detect the approaching vehicle 2 by eliminating erroneous detection caused by these.

As described above, the third embodiment that performs labeling in the window B has the following effects.
(1) In addition to the effects of the first embodiment, it is possible to eliminate the false detection caused by the minute disturbance of the image due to the image noise or the case where a small object such as a leaf or a bush crosses the front of the camera 10 and reliably enter. The vehicle 2 can be detected.

A fourth embodiment of the present invention is shown in FIG.
As shown in FIG. 6, this embodiment extracts the change area in the window B as a lump, and also extracts the change area in the entire image as a lump. When the latter lump includes the former lump, ”There are vehicles exceeding the limit”.
That is, in the height limit excess detection device of the third embodiment, the image processing unit 20 receives the video signal of the ITV camera 10 and sets the window B set in the peripheral portion of the region corresponding to the limit height A in the input image. When change detection is performed in window B and changes are detected in window B, the areas that have changed are combined, and geometric features such as area, perimeter, and aspect ratio are calculated. When the calculated value is within the range corresponding to the detection object set in advance, change detection processing is further performed using the entire input image as the target area, and the changed areas are combined, and there is a change inside the window B. Calculate geometric features such as area, perimeter, and aspect ratio of the target area including the area, and if these calculated values are within the range corresponding to the preset detection target, `` There is an object that exceeds the height limit '' ”Is detected and the alarm device 30 And outputs it to.

In the third embodiment, when a change area of a certain size is detected when the window B is small, for example, a large disturbance due to an environmental change of the shooting location, a newspaper or a large animal flying in the wind, etc. When crossing, there is a possibility of output with the height limit exceeded even though there is no approaching vehicle 2.
On the other hand, according to the present embodiment, by evaluating the size of the moving area in the entire image together with the inside of the window B, it is possible to eliminate erroneous detection caused by these and reliably enter the vehicle 2 Can be detected.

As described above, the fourth embodiment that performs change detection and labeling on the entire video has the following effects.
(1) In addition to the effects of the first and third embodiments, false detection caused by large disturbances due to changes in the environment of the shooting location, or when newspapers or large animals flying in the wind cross the front of the camera 10 Therefore, the approaching vehicle 2 can be reliably detected.

A fifth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 7, in this embodiment, two windows B1 and B2 are set in the traveling direction in the video image of the camera 10, and the traveling direction of the vehicle 2 is determined by evaluating the timing at which each change is detected. The approaching vehicle 2 is detected.
That is, in the height limit excess detection device of the first embodiment, the image processing unit 20 inputs the video signal of the ITV camera 10 and 2 in the lateral direction in the peripheral portion of the region corresponding to the limit height A in the input image. Two windows B1 and B2 are set, change detection processing is performed in the two set windows B1 and B2, and a change is detected in the window B1 farther from the height restriction point C. When a change is detected in the window B2 closer to the restricted portion C, “height limit exceeding object intrusion” is detected and output to the alarm device 30 or the like.
In the first embodiment, when one window B is used and a change is detected here, an output with a height limit exceeded is output, so the traveling direction of the passing vehicle 2 cannot be known.
This also applies to the method using an ultrasonic sensor or a light transmission type sensor when only one sensor is used.

On the other hand, according to the present embodiment, it is possible to know the approach direction of the vehicle 2 by performing motion detection individually in the two windows B1 and B2 set in the lateral direction, so that the direction away from the height restriction point C Vehicle 2 that moves to the vehicle, that is, vehicle 2 that does not affect height restriction point C is excluded from “height restriction excess detection” and only dangerous vehicle 2 that attempts to enter height restriction point C is detected. Is possible.
Moreover, in another method, it is necessary to install two sensors in order to know the approach direction of the vehicle 2, but there is an advantage that only one camera 10 is used in the apparatus of this embodiment and no additional installation is necessary.
Note that the method of evaluating the intrusion direction using the two windows B1 and B2 shown in the present embodiment is used in place of the motion detection in the window B of the image processing unit 20 in the second to fourth embodiments. And has similar advantages with respect to approach direction evaluation.

As described above, the fifth embodiment in which the approach direction is determined by the two windows B1 and B2 has the following effects.
(1) In addition to the effects of the first embodiment, since the direction of entry of the vehicle 2 can be known, the vehicle 2 that moves in a direction away from the height-restricted portion C is excluded and the height-restricted portion C enters. It is possible to detect only the dangerous vehicle 2.
(2) In other methods, it is necessary to install two sensors in order to know the approaching direction of the vehicle 2, but only one camera 10 is used in the apparatus of this embodiment, and no additional installation is necessary.

A sixth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 8, in this embodiment, the approach direction is determined by an optical flow.
That is, in the height limit excess detection device according to the first embodiment or the second embodiment, the image processing unit 20 inputs the video signal of the ITV camera 10 and puts it in the peripheral portion of the region corresponding to the limit height A in the input image. When the change detection process in the set window B is performed and a change is detected in the window B, the movement direction of the changed area is calculated, and the calculated movement direction approaches the height restriction point C. At a certain time, “height limit exceeded object intrusion detected” is detected and output to the alarm device 30 or the like.
The method for calculating the direction of movement of the region that has changed in the window B can be extracted by, for example, the optical flow method (Non-patent Document 1).
In this method, as shown in FIG. 8, the approaching vehicle 2 is detected by calculating the moving direction together with the change in the window B.

According to this, while the two windows B1 and B2 are used in the fifth embodiment, the vehicle 2 that moves in the direction away from the height restriction portion C by the processing of one window B is excluded, and the height is reduced. It is possible to detect only the dangerous vehicle 2 that is going to enter the restricted part C.
In addition, since the number of windows B to be set is small, the setting is relatively easy, and the moving direction of the change area in the window B is directly calculated, so that there is an advantage that an accurate moving direction can be evaluated.
Note that the method of evaluating the intrusion direction of the change area in the window B shown in the present embodiment can be used instead of the motion detection in the window B of the image processing unit 20 in the second to fourth embodiments. There are similar advantages regarding the evaluation of the approach direction.

As described above, the sixth embodiment in which the approach direction is determined by the optical flow has the following effects.
(1) In addition to the effects of the first embodiment, the fifth embodiment has the effects of the fifth embodiment. The vehicle 2 that moves in a direction away from the height-restricted portion C is excluded, and a dangerous vehicle that attempts to enter the height-restricted portion C. Only 2 can be detected.
(2) Since the number of windows B to be set is small, setting is relatively easy.
(3) Since the moving direction of the change area in the window B is directly calculated, the accurate moving direction can be evaluated.

The seventh embodiment of the present invention is eliminated based on FIG.
As shown in FIG. 9, the present embodiment performs change detection processing by local region time correlation change analysis.
That is, in the change detection processing period in the window B in the image processing unit 20 of the first to sixth embodiments, the video is divided into appropriate small areas, the background image acquired in advance for each small area, and the current image. Calculating the correlation value with the image of the corresponding small area in the same video, and detecting “exceeding the height limit” when detecting the small change area in window B based on the temporal change To the alarm device 30 or the like.
The present embodiment uses the stationary obstacle detection method (hereinafter referred to as method 1) of Patent Document 4 as the change detection processing in the first embodiment.

Therefore, there is an advantage that it is possible to detect the state where the object after the change is stationary along with the presence or absence of the change for each small region.
As shown in FIG. 9, the window B set in the camera video is a small area further divided according to the procedure of method 1.
FIG. 10 shows an example of the temporal change of the correlation value of a certain small area.
According to method 1, when the correlation value of a small region changes as shown in FIG. 10, the state of the small region is changed (I), no change (II), and stationary object detection (III). Can be classified.
As a result, it is possible to eliminate erroneous detection due to noise or the like of a fine video in which a change is detected only in a part of the small area, and the vehicle 2 moving in the window B is detected. It is possible to detect a state of entering and stopping.
Further, by appropriately updating the background image by a background image acquisition method based on a temporal correlation change (see Patent Document 5), it is possible to eliminate the risk of erroneously detecting background fluctuations due to weather and time.

As described above, the seventh embodiment that performs the change detection process based on the local region time correlation change analysis has the following effects.
(1) In addition to the effects of the first embodiment, it is possible to eliminate erroneous detection caused by fine video noise or the like in which a change is detected only in a part of a small area.
(2) While detecting the vehicle 2 moving in the window B, it is possible to detect a state in which the vehicle 2 has entered and stopped.
(3) By appropriately updating the background image, it is possible to eliminate the risk of erroneously detecting background changes due to weather and time.

An eighth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 11, in this embodiment, a stepwise alarm is performed in a plurality of windows B1 and B2.
In the height limit excess detection device according to the first embodiment, the image processing unit 20 inputs a video signal of the ITV camera 10 and has a plurality of windows B1 and B2 in a peripheral portion of a region corresponding to the limit height A in the input image. , And change detection processing in each of the set windows B1 and B2 is performed individually, and when a change is detected in the windows B1 and B2, it corresponds to “exceeding the height limit” of each of the windows B1 and B2. A different alarm is output to the alarm device 30 or the like.
For example, as shown in FIG. 11, when two windows B1 and B2 are set in the traveling direction of the vehicle 2, that is, in the horizontal direction, when a change is detected in the window B1 farther from the height restriction point C, “caution” ”Is output, and when a change is detected in the window B2 close to the height restriction point C, an“ alarm ”is output.

As a result, in the case of “caution”, the alarm device 30 turns on a lamp or a warning light at the height-restricted point C to notify the driver of attention and prevent the vehicle 2 from entering in advance. Can be used for stepwise operation of over-height limit monitoring, such as forcibly preventing intrusion of the vehicle 2 with a circuit breaker, etc. or issuing an alarm to the central monitoring station to deal with emergencies early. .
As another example, as shown in FIG. 12, when two windows B3 and B4 are set in the upper and lower height directions of the limit height A, a change is detected in the lower window B4. “Caution” is output, and “warning” is output when a change is detected in the upper window B3.
As a result, the warning device 30 displays a warning of “traveling caution” in the case of “caution” to inform the driver that he / she is careful when traveling because it is close to the limit height A, and in the case of “warning” ”To notify the driver of preventing the vehicle 2 from entering the vehicle, it becomes possible to perform stepwise operation with respect to the warning display for the driver whose height has been exceeded.

In the two examples described above, the two windows B1, B2 or B3, B4 are set in the vertical direction and the horizontal direction. However, the locations of the plurality of windows B1 to B4 depend on the road slope and the situation of the height restriction point C. It may be set at an appropriate position including an oblique direction.
In another method using an ultrasonic sensor or a light transmission type sensor, it is necessary to install a plurality of sensors corresponding to the number of stages in order to realize a stepwise detection of the vehicle height. There is an advantage that the number of cameras 10 used in the apparatus is one and there is no need for expansion.
Note that the method of evaluating the intrusion direction using the plurality of windows B1 to B4 shown in the present embodiment is used instead of the motion detection in the window B of the image processing unit 20 in the second to seventh embodiments. Have the same advantages with respect to phased operations.

As described above, the eighth embodiment in which the stepwise alarm is performed in the plurality of windows B1 to B4 has the following effects.
(1) In addition to the effects of the first embodiment, it is possible to perform the stepwise operation of the height limit excess monitoring.
(2) Step-by-step operation is possible for warning indications for drivers who exceed the height limit.
(3) In other methods, in order to realize stepwise detection of the height of the vehicle 2, it is necessary to install a plurality of sensors corresponding to the number of steps, but the device of this embodiment does not need to be added. .

A ninth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 13, in this embodiment, the installation position and the direction of the ITV camera 11 are changed.
That is, the height limit excess detection device according to the present embodiment includes the ITV camera 11 and the image processing unit 20.
The ITV camera 11 has a vehicle 2 on the road with a horizontal optical axis at a position having the same height as the restricted height A such as the pillar 1 on the side of the road in the vicinity or near the restricted height C of the road or passage. Install in the direction of entry.
The image processing unit 20 inputs the video signal of the ITV camera 11, performs a change detection process in the window B set in the peripheral part of the area corresponding to the restricted height A in the input image, and changes in the window B. When it is detected, the presence of “over height limit” is detected and output to the alarm device 30 or the like.

As shown in FIG. 13, the installation position and direction of the camera 11 of the present embodiment are different from the position and direction in which the camera 10 of the first embodiment faces in the direction orthogonal to the road.
In this embodiment, the camera 10 is installed in the direction in which the entrance direction of the vehicle 2 is seen from the height-restricted portion C, whereas the camera 10 is installed in the direction perpendicular to the road in the first embodiment. Thus, in addition to the same effects as those of the first embodiment, the camera 11 can be installed in the vicinity of the height restriction portion C, so that there is an advantage that it can be easily installed.
For example, when the height restriction point C is a railroad crossing or a crossover, the camera 10 can be directly installed on the bridge pier portion, so that it is not necessary to stand the roadside pillar 1 for installing the camera 10.
Further, the installation location of the ITV camera 11 shown in the present embodiment can be applied as the installation location of the ITV camera 10 in the second to eighth embodiments, and there is a similar advantage with respect to the ease of camera installation.
In particular, in the second embodiment, the operator can view the image stored in the image recording unit 40 when the height limit excess detection is detected or the images before and after the image and visually confirm the situation at that time. Since the image of the camera 10 installed at the position of the camera 10 captures the upper surface direction of the entering vehicle 2, it is possible to capture not only the shape of the vehicle 2 but also the driver and the license plate at the same time. Get more information on identifying

As described above, the ninth embodiment in which the installation position and the direction of the ITV camera are changed has the following effects.
(1) In addition to the effects of the first embodiment, the camera 11 can be easily installed because it can be installed in the vicinity of the height-restricted portion C.
(2) There is no need to stand up the pillar 1 beside the road for installing the camera 11.
(3) Since the front direction of the entering vehicle 2 is imaged in the image of the camera 11 installed at the position of this embodiment, it is possible to simultaneously image not only the shape of the vehicle 2 but also the driver and the license plate. Therefore, more information regarding the identification of the approaching vehicle 2 can be obtained.

A tenth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 13, the present example is a modification of the ninth example.
That is, the height limit excess detection device according to the present embodiment includes the ITV camera 12, the image processing unit 20, and the image recording unit 40.
The ITV camera 12 is positioned at the same height as the restricted height A of the pillar 1 etc. on the side of the road in front of the restricted height C of the road or passage, and the direction of the restricted height C with the optical axis horizontal. Install toward.
The image processing unit 20 receives the video signal from the ITV camera 10, performs a change detection process in the window B set in the peripheral part of the area corresponding to the restricted height A in the input image, and changes the window B. When it is detected, the presence of “over height limit” is detected and output to the alarm device 30 or the like.
The image recording unit 40 stores an image at the time of detecting a vehicle exceeding the height limit or images before and after the image.
As shown in FIG. 13, the installation position and direction of the camera 11 of the present embodiment are different from the position and direction in which the camera 10 of the first embodiment faces the direction orthogonal to the road.

In the present embodiment, the camera 10 is installed in the direction in which the height-restricted portion C is viewed, whereas the camera 10 is installed in a direction orthogonal to the road in the second embodiment. In addition to the effect, there is an advantage that the height restriction point C, for example, the status of a railroad crossing and a crossover can be recorded simultaneously on the image when the height limit excess is detected.
This is because, for example, when an accident occurs that damages the height-restricted portion C in a certain time zone, and a plurality of height-limit excess warnings are issued during that time zone, the vehicle 2 at which the alarm 2 is detected is detected. It will be a means to know if an accident has occurred.
The installation location of the ITV camera 12 shown in the present embodiment can be applied as the installation location of the ITV camera 10 in Embodiments 3 to 8, and has the same advantages.

As described above, the tenth embodiment in which the installation position and direction of the ITV camera are changed has the following effects.
(1) In addition to the effects of the first embodiment, it is possible to simultaneously record the situation of the height restriction portion C on the video when the height limit excess is detected.
(2) For example, when an accident occurs that damages a bird's restriction in a certain time zone, and multiple height limit over warnings are issued during that time zone, the vehicle 2 at which alarm is detected Become a means of knowing if an accident occurred.

An eleventh embodiment of the present invention will be described with reference to FIG.
This embodiment is a combination of the uplink and downlink of the tenth embodiment.
That is, the height limit excess detection device according to the present embodiment includes two ITV cameras 13, 14, an image processing unit 20, and an image recording unit 40 installed on the opposite side of the height limit point C in the traveling direction. Consists of.
One ITV camera 13 is positioned at the same height as the restricted height A of the pillar 1 etc. on the side of the road in front of the restricted height C, and the optical axis is horizontally oriented in the direction of the restricted height C. The other ITV camera 14 is located at the same height as the restricted height A of the roadside pillar 1 etc. on the opposite side of the first camera 10 with respect to the restricted height C. At this position, the optical axis is placed horizontally and in the direction of the height restriction point C.
The image processing unit 20 individually inputs video signals from the ITV camera 10 and individually performs change detection processing in the window B set in the peripheral portion of the region corresponding to the restricted height A in the input image. When a change is detected during B, the “height limit excess” is detected and output to the alarm device 30 or the like.
The image recording part 40 preserve | saves the image of the two ITV cameras 10 at the time of the vehicle over height restriction | limiting detection, or the image | video before and behind that.

As shown in FIG. 14, in this embodiment, the two cameras 13 and 14 are installed at positions that face each other across the height restriction portion C.
In the present embodiment, the camera 12 installed in the direction of viewing the height-restricted portion C of the embodiment 10 is installed as the cameras 13 and 14 in both the upward and downward directions of the road crossing the height-restricted portion C. Since the situation of the height restriction portion C is simultaneously recorded in the images of the cameras 13 and 14 that have detected that the height limit has been exceeded, the front direction of the vehicle 2 that enters is captured in the images of the other cameras 13 and 14. It is possible to simultaneously image not only the shape of the vehicle 2 but also the driver and the license plate, and more information regarding the identification of the approaching vehicle 2 can be obtained.

As described above, the eleventh embodiment linking the uplink and the downlink of the tenth embodiment has the following effects.
(1) In addition to the effects of the first embodiment, the situation of the height restriction portion C is simultaneously recorded on the images of the cameras 13 and 14 that have detected that the height limit is exceeded, and the video of the other cameras 13 and 14 is entered. Since the front direction of the vehicle 2 is imaged, it is possible to simultaneously image not only the shape of the vehicle 2 but also the driver and the license plate, and more information regarding the identification of the approaching vehicle 2 can be obtained.

A twelfth embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 15, in this embodiment, the camera 15 is installed obliquely downward at a limit height A.
That is, the height limit excess detection device according to the present embodiment includes the ITV camera 15 and the image processing unit 20.
The ITV camera 15 has the optical axis orthogonal to the road at a position where the center of the lens is at the same height as the limit height A on the pillar 1 on the side of the road before the height limit point C of the road or passage. In the direction, it is installed downward in the range where the periphery of the restricted height A is imaged.
The image processing unit 20 receives the video signal of the ITV camera 10, performs a change detection process in the window B set in the peripheral part of the region corresponding to the tree height in the input image, and changes the window B. When it is detected, the presence of “over height limit” is detected and output to the alarm device 30 or the like.

As shown in FIG. 15, when the approach direction of the vehicle 2 is viewed from the height restriction point C, the camera 15 is directed downward so that the lens center is positioned at the same height as the restriction height A of the roadside pillar 1. It is installed.
For example, as shown in FIG. 16, the image of the camera 15 can see the entire vehicle 2 because the restricted height A position has moved above the image compared to the camera image of the first embodiment of FIG. 3. It has become.
In the present embodiment, the camera 10 is installed horizontally in the first embodiment, but the camera 15 is installed downward in a range where the periphery of the restricted height A can be seen. However, in this embodiment, it is possible to image the situation of the intruding vehicle or the like in most of the lower part of the video.

According to the installation method of the ITV camera 15 shown in the present embodiment, by making the lens center the same as the limit height A, the position of the limit height A becomes a straight line above the center in the camera image. In addition, it is possible to detect that the height limit has been exceeded in the same manner as in the first to eleventh embodiments, and there are the same advantages as the respective embodiments.
In particular, in the second embodiment, it is possible for the operator to visually check the situation at the time when the operator sees the image at the time when the height limit excess detection stored in the image recording unit 40 or the video before and after that is detected. In the video of the camera 10 installed in the direction, the approaching vehicle 2 is captured larger than in the case of the second embodiment, so that more information regarding the identification of the approaching vehicle 2 can be obtained.

As described above, according to the twelfth embodiment in which the obliquely downward camera is installed at the restricted height A, the following effects are obtained.
(1) In addition to the effects of the first embodiment, it is possible to image the situation of an intruding vehicle or the like in the lower part of the video.
(2) Since the approaching vehicle 2 is captured in the video of the camera 15 larger than in the case of the second embodiment, more information regarding the identification of the approaching vehicle 2 can be obtained.

  INDUSTRIAL APPLICABILITY The present invention is used for an apparatus that detects an approaching vehicle or the like exceeding a restricted height at a place where the height is restricted on a road or a passage.

It is the schematic diagram which looked at the camera installation position of the height restriction excess detection apparatus by this invention from the approach direction of the vehicle 2 from the height restriction location C. FIG. It is a basic lineblock diagram of the height limit excess detection device of the present invention. It is an image figure which can see the vehicle exceeding the restriction | limiting height image | photographed with the camera of FIG. It is a block diagram of the height limit excess detection apparatus of Example 2. FIG. It is explanatory drawing which shows a mode that the change area | region in a window is extracted as a lump. It is explanatory drawing which evaluated the relationship between the lump which is a change area | region in a window, and the lump which is a change area | region in all the images. It is explanatory drawing which shows a mode that two windows were set to the advancing direction in a camera image | video. It is explanatory drawing which shows the mode of the optical flow which calculates a moving direction with the change in a window. It is explanatory drawing which shows a mode that the window set in the camera image | video was further divided | segmented into the small area | region. It is the graph which showed the example of the time change of the correlation value of a small area. It is explanatory drawing which shows a mode that two windows were set to the advancing direction of the vehicle. It is explanatory drawing which shows a mode that two windows were set to the height direction of the upper part of a restriction | limiting height, and a lower part. It is explanatory drawing which shows the installation position and direction of the camera in Example 1, 9, 10. FIG. FIG. 16 is an explanatory diagram illustrating installation positions of two cameras according to an eleventh embodiment. It is the schematic diagram which looked at the camera installation position of the height restriction excess detection apparatus by Example 12 from the height restriction location C from the approach direction of the vehicle. FIG. 16 is an image captured by the camera of Example 12.

Explanation of symbols

1 pillar 2 vehicle 10, 11, 12, 13, 14, 15 ITV camera 20 image processing device 21 image input means 22 window processing means 23 change detection means 24 detection output means 30 alarm device 40 image recording unit A limit height B, B1, B2, B3, B4 Window C Height restriction

Claims (12)

In a height limit excess detection device that detects an object that exceeds the limit height, such as an approaching vehicle, that is installed in front of the height limit point of a road or a passage, the ITV camera and image processing unit The camera is configured so that the optical axis is horizontal and perpendicular to the road, with the road direction facing the same height as the restricted height of the pillars on the roadside, etc., at a point in front of the restricted height of the road or passage. The image processing unit inputs the video signal of the camera, performs change detection processing of the window portion set in the peripheral portion of the area corresponding to the restricted height in the input image, and A height limit excess detection device that detects and outputs “exceeding a height limit” when a change is detected. In an over-height limit detection device that is installed at a point in front of a height-restricted portion of a road or passage and detects an entering object such as an approaching vehicle that exceeds the limit height, an ITV camera, an image processing unit, and an image recording unit The camera has a horizontal optical axis with the direction of the road facing the road at the same height as the restricted height of the roadside pillars etc. The image processing unit inputs the video signal of the camera, performs change detection processing of the window portion set in the peripheral portion of the area corresponding to the restricted height in the input image, and When a change is detected in the vehicle, the presence of “exceeding the height limit” is detected and output, and the image recording unit stores an image at the time of detecting the vehicle exceeding the height limit or images before and after the vehicle. Height limit exceeded detection device. 3. The height limit excess detection device according to claim 1 or 2, wherein the image processing unit inputs a video signal of the camera and is set at a peripheral portion of an area corresponding to the limit height in the input image. When a change is detected in the window and changes are detected in the window, the areas that have changed are combined and the geometric features such as area, perimeter, and aspect ratio are calculated. A height limit excess detection device that detects and outputs “there is an object that exceeds the height limit” when the value is within a range corresponding to a preset detection target. 4. The height limit excess detection device according to claim 3, wherein the image processing unit inputs a video signal of the camera and detects a change in a window portion set in a peripheral portion of a region corresponding to the limit height in the input image. When the change is detected in the window, the areas that have changed are combined, the geometric features such as area, perimeter, and aspect ratio are calculated, and these calculated values are preset. When the change is within the range corresponding to the detected object, the change detection process is further performed using the entire input image as the target area, the areas that have changed are combined, and the area of the target area including the area that has changed inside the window , Geometric lengths such as perimeter, aspect ratio, etc., and when these calculated values are within the range corresponding to the preset detection target, "exceeding height limit object" is detected and output Height restriction characterized by Over-detection device. 2. The height limit excess detection device according to claim 1, wherein the image processing unit inputs a video signal of the camera, and sets two windows in a lateral direction in a peripheral portion of a region corresponding to the limit height in the input image. Then, the change detection processing of each of the two set window portions is performed, and after a change is detected in the window farther from the height restriction location, the change is detected in the window closer to the height restriction location after a certain time. A height limit excess detection device, which sometimes detects and outputs "There is an object that exceeds the height limit". 3. The height limit excess detection device according to claim 1 or 2, wherein the image processing unit inputs a video signal of the camera and is set at a peripheral portion of an area corresponding to the limit height in the input image. When a change is detected in the window and the change is detected in the window, the movement direction of the changed area is calculated, and when the calculated movement direction is a direction approaching the height restriction point, A height limit excess detection device that detects and outputs “excess object intrusion”. The change detection process in the window in the image processing unit according to any one of claims 1 to 6 divides the video into appropriate small areas, and the correspondence between the background image acquired in advance for each small area and the current video The correlation value with the image of the small area to be calculated is calculated, and when the change small area in the window is detected based on the temporal change, it is detected and output that there is an “over height limit” A height limit excess detection device. 2. The height limit excess detection device according to claim 1, wherein the image processing unit inputs a video signal of the camera, sets a plurality of windows in a peripheral portion of an area corresponding to the limit height in the input image, and sets the window. Each window part change detection process is performed individually, and when a change is detected in the window, a different alarm corresponding to “exceeding the height limit” of each window is output. Excess detection device. In a height limit excess detection device that detects an object that exceeds the limit height, such as an approaching vehicle, that is installed in front of the height limit point of a road or a passage, the ITV camera and image processing unit The camera is configured so that the optical axis is horizontal and in the direction of vehicle entry on the road at a position that is the same height as the restricted height of a roadside pillar, etc. The image processing unit inputs the video signal of the camera, performs change detection processing of the window portion set in the peripheral portion of the area corresponding to the restricted height in the input image, and changes in the window A height limit excess detection device that detects and outputs “exceeding a height limit” when an error is detected. In a height limit excess detection device that detects an object exceeding a height limit, such as an approaching vehicle that is installed at a point in front of a height limit point on a road or passage, and that exceeds the limit height, an ITV camera, an image processing unit, The camera is composed of an image recording unit, and the camera is positioned at the same height as the restricted height of the roadside pillars, etc., at a point in front of the restricted height of the road or passage. The image processing unit inputs the video signal of the camera, performs change detection processing of the window portion set in the peripheral portion of the area corresponding to the restricted height in the input image, and When a change is detected in the vehicle, the presence of “exceeding the height limit” is detected and output, and the image recording unit stores an image at the time of detecting the vehicle exceeding the height limit or images before and after the vehicle. Height limit exceeded detection device. In the height limit excess detection device that detects an object that exceeds the height limit, such as an approaching vehicle that is installed in front of the height limit location on a road or passage, Consists of two ITV cameras, an image processing unit, and an image recording unit installed on the opposite side of the front side. One of the cameras is the same as the restricted height of the fences on the roadside in front of the height restriction point. The optical axis is placed horizontally at the height position in the direction of the height restriction location, and the other camera is a pillar on the roadside at a point opposite to the one camera with respect to the height restriction location. Installed at the same height as the restricted height, etc., with the optical axis oriented horizontally and in the direction of the height restricted portion, and the image processing unit individually inputs the video signal of the camera, Change detection processing of the window part set at the periphery of the area corresponding to the limit height of Each is performed individually, and when a change is detected in the window, the presence of “exceeding the height limit” is detected and output, and the image recording unit detects the two cameras when the vehicle exceeds the height limit. A height limit excess detection device characterized in that it stores an image or images before and after the image. In a height limit excess detection device that detects an object that exceeds the limit height, such as an approaching vehicle, that is installed in front of the height limit point of a road or a passage, the ITV camera and image processing unit The camera is configured so that the center of the lens is at the same height as the limit height on a pillar on the side of the road in front of the restricted height of the road or passage, and the optical axis is perpendicular to the road. The window portion is set downward in the range where the periphery of the limit height is imaged, and the image processing unit inputs the video signal of the camera and is set in the periphery of the region corresponding to the limit height in the input image A height limit excess detection device that detects and outputs “exceeds a height limit” when a change is detected in a window.

Images