JP6024349B2 - Monitoring device and monitoring system - Google Patents

Description

  The present invention relates to a monitoring device and a monitoring system that detect an object based on a captured image.

  2. Description of the Related Art Conventionally, there is known an apparatus that detects the presence or absence of an article by photographing a shadow generated by light emitted from one direction (see, for example, Patent Document 1). In a conventional monitoring apparatus, a shadow image of an article is specified by comparing the photographed image with a reference image that has been photographed in advance in the absence of the article, and the presence or absence of the article is detected based on the presence or absence of the shadow image.

JP-A-8-146147

  However, in the conventional monitoring device, since an object is detected based on a shadow generated by light irradiation from one direction, there is a case where there is almost no shadow depending on the direction in which the object is irradiated with light. For example, when an object has a thin shape, it is difficult to detect a shadow caused by light irradiated toward a side surface having a small width.

  Further, in the conventional monitoring device, it is difficult to determine whether the image area shown in black is a shadow of an object or dirt on the road surface. Therefore, there has been a problem that it is misidentified as a shadow in spite of being mere dirt, or misidentified as being dirt despite being a shadow of an object.

  Therefore, the present invention has been made in view of these points, and provides a monitoring device that can detect an object with high accuracy regardless of the shape of the object by irradiating a plurality of lights from different directions. The purpose is to do.

  In order to solve the above problems, in the first aspect of the present invention, an acquisition unit that acquires a captured image from an imaging unit that captures an object and generates a captured image, and a plurality of objects from different directions with respect to the object A control unit that controls an irradiation unit that emits light, a recognition unit that recognizes an image of a shadow generated by the irradiation unit irradiating the object with a plurality of lights, and a shadow that is recognized by the recognition unit. There is provided a monitoring device including a detection unit that detects an object based on at least.

  In the monitoring apparatus described above, the control unit may cause the irradiation unit to sequentially irradiate a plurality of lights from different directions. The monitoring device extracts a shadow image by comparing a captured image extraction unit that extracts a plurality of captured images captured at a timing when the irradiation unit emits light and a plurality of captured images extracted by the captured image extraction unit. And a shadow image extraction unit that performs the operation.

  Moreover, in the monitoring apparatus described above, the control unit may cause the imaging unit to capture images in synchronization with the timing at which the irradiation unit emits light. The monitoring apparatus may further include an object image extraction unit that extracts an image of the object from the captured image, and the detection unit detects the height of the object based on at least one of the image of the object and the image of the shadow. , At least one of area and volume may be detected.

  In the monitoring device, the irradiating unit irradiates the position of the object detected by the detecting unit with coherent light, and the detecting unit is based on the shape of the coherent light reflected in the photographed image, among the height, area, and volume of the object. At least one of the above may be detected. In the monitoring device, the photographing unit may photograph a vehicle traveling on the road, and the irradiating unit may irradiate light while the vehicle is not reflected in a photographed image photographed by the photographing unit.

  According to a second aspect of the present invention, there is provided a monitoring system including an imaging device that captures an object and generates a captured image, an irradiation device that irradiates the object with light, and a data management device that analyzes the captured image. A control unit that controls the irradiation device to irradiate a plurality of lights from different directions on the object, and recognizes an image of a shadow generated by the irradiation device irradiating the object with a plurality of lights in the captured image Provided is a monitoring system including a recognition unit and a detection unit that detects an object based at least on a shadow recognized by the recognition unit.

  According to a third aspect of the present invention, there is provided a monitoring system including an imaging device that captures an object and generates a captured image, and an irradiation device that irradiates the object with light. A control unit that controls the irradiation device to irradiate a plurality of lights from different directions; a recognition unit that recognizes an image of a shadow generated by the irradiation device irradiating the object with a plurality of lights in the captured image; and a recognition unit And a detection unit that detects an object based at least on the shadow recognized by the computer.

  According to the present invention, it is possible to detect an article with high accuracy regardless of the shape of an object by irradiating a plurality of lights from different directions.

The structural example of the monitoring system in 1st Embodiment is shown. An example of the usage aspect of the monitoring system in 1st Embodiment is shown. 1 shows a configuration example of a monitoring apparatus according to a first embodiment. The other structural example of the monitoring apparatus of 1st Embodiment is shown. The position coordinate in a picked-up image is shown. An example of the relationship between the position coordinate in a picked-up image and the position in an actual imaging region is shown. It is a top view of the aspect in which the irradiation part is irradiating the object with light. It is a side view of the aspect in which the irradiation part is irradiating the object with light. The aspect which an irradiation part irradiates coherent light is shown. An example of a captured image showing an object irradiated with coherent light is shown. The structural example of the monitoring system of 2nd Embodiment is shown. The structural example of the monitoring system of 3rd Embodiment is shown.

<First Embodiment>
[Configuration of the monitoring system 10]
FIG. 1 shows a configuration example of a monitoring system 10 in the first embodiment. FIG. 2 shows an example of how the monitoring system 10 is used in the first embodiment.

  In FIG. 1, a monitoring system 10 includes, for example, a plurality of monitoring devices 100 (monitoring device 100-1, monitoring device 100-2,..., Monitoring device 100-n connected in a daisy chain, where n is a natural number of 3 or more. And a data management device 400 connected to the plurality of monitoring devices 100. The data management device 400 is a server, for example. A plurality of monitoring devices 100 are connected by a communication line 50. The communication line 50 is an 8-core cable for LAN (local area network), for example.

  The monitoring system 10 may include a hub 500 between the data management device 400 and the monitoring device 100-1. Each monitoring device 100 may be connected to the data management device 400 via the hub 500. The monitoring system 10 may include a plurality of groups of monitoring devices 100 connected to the hub 500. The monitoring system 10 may include a monitor 600 that displays an image captured by the monitoring device 100.

  As shown in FIG. 2, the monitoring apparatus 100 generates a captured image including an image of an object shadow caused by light emitted from a plurality of different positions and the image of the object. Specifically, the monitoring apparatus 100 detects the object based on the image of the shadow caused by the first light irradiated on the first irradiation range and the second light irradiated on the second irradiation range. Detect the presence or absence. The light may be emitted from a position where the monitoring apparatus 100 is installed, or may be emitted from a position other than the monitoring apparatus 100.

[Basic configuration of monitoring apparatus 100]
FIG. 3 shows a configuration example of the monitoring apparatus 100 according to the first embodiment. The monitoring device 100 includes an imaging unit 110, an acquisition unit 120, an irradiation unit 130, a control unit 140, a recognition unit 142, a detection unit 144, and a transmission / reception unit 150. The photographing unit 110 includes, for example, a lens and a CCD (charge coupled device), and photographs an object to generate a photographed image. It is preferable that the imaging unit 110 has a plurality of lenses and captures a stereoscopic image.

  The acquisition unit 120 acquires a captured image from the imaging unit 110. The acquisition unit 120 may acquire a captured image of the object generated by the imaging unit 110 and transmit a digital image generated by performing analog / digital conversion on an image signal based on the acquired captured image to the recognition unit 142.

  The irradiation unit 130 irradiates the object with a plurality of lights from different directions. For example, the irradiation unit 130 includes a plurality of light sources that can change the irradiation direction. The plurality of light sources may be provided at different positions in the casing of the monitoring apparatus 100, or may be connected to the casing of the monitoring apparatus 100 via a cable. The light irradiated by the irradiation unit 130 may be visible light, or may be infrared light or ultraviolet light.

  The control unit 140 controls the irradiation unit 130. Specifically, the control unit 140 controls at least one of the timing at which the irradiation unit 130 irradiates light, the direction in which light is irradiated, and the intensity of light. The control unit 140 may control the timing at which the imaging unit 110 captures an image.

  In the monitoring device 100 in which the imaging unit 110 captures a vehicle traveling on a road, the control unit 140 causes the irradiation unit 130 to irradiate light, for example, while the vehicle is not in a range where the light irradiated by the irradiation unit 130 reaches. Specifically, the control unit 140 causes the irradiating unit 130 to irradiate light when it is confirmed that the vehicle is not captured in the captured image captured within a predetermined time immediately before. The control unit 140 may cause the irradiation unit 130 to irradiate light at a timing at which the vehicle is not shown in a captured image captured by another adjacent monitoring device 100.

  The recognition unit 142 recognizes an image of a shadow generated by the irradiation unit 130 irradiating the object with a plurality of lights in the captured image. Since the irradiation unit 130 irradiates a plurality of lights from different directions, a shadow having a size that can be recognized by the recognition unit 142 is generated regardless of the shape of the object.

  For example, the recognition unit 142 recognizes a region having a relatively low luminance in the captured image as a shadow image. When the intensity of light emitted by the irradiating unit 130 is sufficiently strong, even if the color of the object itself is black, the area other than the shadow appears white when it hits the light. Therefore, the recognition unit 142 may recognize a predetermined color area (for example, a black area) in the captured image as a shadow image.

  The detection unit 144 detects the presence or absence of an object in the captured image. Specifically, the detection unit 144 detects an object based at least on the shadow image recognized by the recognition unit 142. For example, when the recognition unit 142 recognizes a shadow image, the detection unit 144 detects that a three-dimensional object exists. The detection unit 144 may determine that there is an object when the shadow image recognized by the recognition unit 142 is larger than a predetermined size. The detection unit 144 may notify the other monitoring device 100 and the data management device 400 that an object has been detected.

  The transmission / reception unit 150 transmits to the data management device 400 that the detection unit 144 has detected an object, and receives various types of information from the data management device 400. The transmission / reception unit 150 may transmit / receive data to / from another monitoring device 100 connected in a daisy chain. For example, the transmission / reception unit 150 of the monitoring device 100-2 receives an image from the transmission / reception unit 150 of the adjacent monitoring device 100-3 and transmits the image to the data management device 400 via the transmission / reception unit 150 of the monitoring device 100-1. .

  As described above, the monitoring device 100 detects an object based on a shadow generated by light irradiated from a plurality of different directions, so that even if the object has a thin shape, the object is highly accurate. Can be detected.

[Light is emitted sequentially from different directions]
FIG. 4 shows another configuration example of the monitoring device 100 according to the first embodiment. 4 is different from the monitoring apparatus 100 shown in FIG. 3 in that it further includes a captured image extraction unit 170, a shadow image extraction unit 180, and an object image extraction unit 190.

  The control unit 140 may cause the irradiation unit 130 to sequentially irradiate a plurality of lights from different directions. When the irradiation unit 130 sequentially irradiates the object with a plurality of lights from different directions, the imaging unit 110 generates a plurality of captured images including an image of the object and a shadow image of the object when the light is irradiated from different directions. can do.

  The captured image extraction unit 170 extracts a plurality of captured images captured at the timing when the irradiation unit 130 irradiates light from a plurality of captured images captured by the capturing unit 110. For example, the captured image extraction unit 170 extracts a captured image captured at the timing when the irradiation unit 130 irradiates light based on the luminance of the captured image.

  The shadow image extraction unit 180 extracts a shadow image from the captured image captured by the imaging unit 110. Specifically, the shadow image extraction unit 180 extracts a shadow image by comparing a plurality of captured images extracted by the captured image extraction unit 170. For example, the shadow image extraction unit 180 compares a plurality of captured images with different directions of irradiated light among the captured images extracted by the captured image extraction unit 170, and brightness and chromaticity among the plurality of captured images. A region in which at least one of the two is different is determined as a shadow image.

  The control unit 140 may cause the photographing unit 110 to photograph in synchronization with the timing when the irradiation unit 130 irradiates light. The control unit 140 causes the image capturing unit 110 to perform image capturing in synchronization with the light irradiation timing of the irradiation unit 130, so that the captured image extraction unit 170 needs to extract an image at the time when light is irradiated from a large number of captured images. Disappears.

[Detect the size of an object]
The monitoring apparatus 100 may further include an object image extraction unit 190 that extracts an object image from the captured image in order to calculate the size of the object. For example, the object image extraction unit 190 extracts an area surrounded by a plurality of shadow images extracted by the shadow image extraction unit 180 as an object image. The object image extraction unit 190 may extract an object image based on at least one of luminance and chromaticity in the captured image.

  The detection unit 144 is based on at least one of the object image extracted by the object image extraction unit 190 and the shadow image extracted by the shadow image extraction unit 180, and includes at least one of the height, area, and volume of the object. Detect one. The detection unit 144 may detect the size of the object based on the relationship between the position coordinates in the captured image described below and the actual position on the road.

  FIG. 5 shows position coordinates in the captured image. An X axis is provided in a direction parallel to the traveling direction of the vehicle in the captured image, and a Y axis is provided in a direction perpendicular to the X axis. When the resolution of the captured image is, for example, XGA (number of pixels: 1024 × 768), the maximum value of coordinates on the X axis is 1024, and the maximum value of coordinates on the Y axis is 768. In this specification, the position coordinates of an object whose position on the X-axis is x and whose position on the Y-axis is y are expressed as (x, y). For example, the position coordinates of an object shown in the center of a 1024 × 768 captured image is represented as (512, 384).

  FIG. 6 shows an example of the relationship between the position coordinates in the captured image and the position in the actual capturing area. The trapezoid shown in FIG. 6 indicates an area on the road that is reflected in the image captured by the imaging unit 110. The points A, B, C, D, E, and F on the boundary line of the photographed area are the position coordinates (0, 0), (0, 384), (0, 768), (1024, 0), respectively. , (1024, 384), (1024, 768).

  In the example of FIG. 6, the distance between AD is 5 m and the distance between CF is 10 m, and it can be seen that the actual length per pixel in the X-axis direction differs depending on the position in the Y-axis direction. Similarly, although the number of pixels between AB and the number of pixels between BC are equal, the actual distance between AB is shorter than the distance between BC. Thus, the actual length per pixel in the Y-axis direction also varies depending on the position in the Y-axis direction.

  FIG. 7A is a top view of an aspect in which the irradiation unit 130 irradiates the object with light. FIG. 7B is a side view of the aspect in which the irradiation unit 130 shown in FIG. 7A irradiates the object with light. The monitoring device 100 irradiates light on a rectangular parallelepiped object having a height H, a width W, and a depth D from a position at a height h from the ground. The distance from the monitoring device 100 to the point S at the tip of the shadow is d. Hereinafter, in the present embodiment, it is assumed that the photographing unit 110 is installed on the top of the object and the photographed image illustrated in FIG. 7A is photographed.

  As shown in FIG. 7A, irradiation with light causes a trapezoidal shadow having a length in the X coordinate direction of Hs, a minimum length in the Y coordinate direction of W, and a maximum length of Ws. The detection unit 144 calculates the height H of the object by H = Hs × h / d based on the length Hs of the shadow in the X coordinate direction in the captured image. The detection unit 144 can determine the width W of the object based on the minimum length W of the shadow in the Y coordinate direction. The detection unit 144 can calculate the area A1 of the first side surface farthest from the monitoring device 100 based on the height H and width W of the object.

  Similarly, the detection unit 144 can calculate the length L of the side surface in the direction orthogonal to the first side surface based on the shadow generated in the light irradiated in the Y coordinate direction. The detection unit 144 can calculate the volume V of the object by area A1 × length L.

  The detection unit 144 may calculate the height, area, and volume of the object based on the image of the object. For example, when three sides of a rectangular parallelepiped object are captured in the captured image, the detection unit 144 can calculate the height H of the object based on the length of the side in the Y-axis direction. The detection unit 144 may calculate the area of the side surface by integrating the lengths of the two sides, or may calculate the volume by integrating the height H of the object and the area of the side surface. The detection unit 144 may calculate the height, area, and volume of the object based on the object image and the shadow image.

  The control unit 140 may calculate the risk level of the object based on the size of the object detected by the detection unit 144. The control unit 140 may output at least one of the size and risk level of the object. The control unit 140 may transmit at least one of the size and the risk level of the object to another monitoring device 100 or the data management device 400 via the transmission / reception unit 150.

  As described above, when the monitoring device 100 detects the size of the object, for example, when there is a falling object on the roadway, the monitoring device 100 displays information according to the size of the object, or other data management device. By providing information to the driver, the driver and the road manager can be alerted.

[Detect the size of an object by irradiating coherent light]
The irradiation unit 130 may irradiate the position of the object detected by the detection unit 144 with coherent light, and the detection unit 144 may detect the presence or absence of the object based on the shape of the coherent light reflected in the captured image. Furthermore, the detection unit 144 may detect at least one of the height, area, and volume of the object based on the shape of the coherent light. Here, the coherent light is light having a property of being difficult to diffuse and reaching far, like laser light.

  FIG. 8 shows a mode in which the irradiation unit 130 installed in the tunnel emits coherent light. FIG. 9 shows an example of a photographed image showing an object irradiated with coherent light. The irradiation unit 130 changes the direction in which the coherent light is irradiated so that the predetermined region within the range captured by the imaging unit 110 is sequentially irradiated with the coherent light. When the coherent light hits the object, the imaging unit 110 can capture the streaks of the coherent light on the object.

  The direction of the coherent light changes along the ridgeline of the object. In the example of FIG. 8, after the coherent light travels straight on the road, the traveling direction changes at a position a where the object and the ground contact. Furthermore, after moving straight along a plurality of side surfaces of the object and changing the traveling direction at a position b on the ridgeline of the object, the vehicle travels straight to a position c on another ridgeline.

  The detection unit 144 detects the height, area, and volume of the object based on the length of the coherent light between the position a and the position b and the length of the coherent light between the position b and the position c. can do. The detection unit 144 calculates an actual length between the position a and the position b calculated by referring to a table indicating the relationship between the position coordinates of the position a, the position b, and the position c and the position in the actual imaging region. Further, the size of the object may be calculated based on the actual length between the position b and the position c.

  Specifically, the detection unit 144 can calculate the height of the object based on the length that the coherent light travels straight on the side surface of the object. The detection unit 144 can calculate the area of the side surface by using the lengths of a plurality of straight lines generated when a plurality of coherent lights in different directions irradiate the side surface of the object. For example, the detection unit 144 can calculate the area of the side surface by integrating the straight lines generated by two coherent lights orthogonal to each other. The detection unit 144 can also calculate the volume of the object by integrating the area of one side and the length of the other side.

  The detection unit 144 may detect the contour line of the object by connecting positions where the traveling direction of the coherent light irradiated from various directions changes. The detection unit 144 may calculate at least one of the height, area, and volume of the object based on the detected contour line.

  As described above, the monitoring apparatus 100 detects the size of an object using coherent light, so that it is possible to detect the presence or absence of an object at a distant place where diffused light is difficult to reach and calculate the size of the object.

<Second Embodiment>
[Monitoring system 10 including photographing apparatus 200 and irradiation apparatus 300]
FIG. 10 shows a configuration of the monitoring system 10 according to the second embodiment. The monitoring system 10 according to the present embodiment includes an imaging device 200 that images an object, an irradiation device 300 that irradiates light on the object, and a data management device 400 that analyzes a captured image acquired from the imaging device 200.

  The data management apparatus 400 includes a control unit 440, a recognition unit 442, a detection unit 444, and a transmission / reception unit 450. The control unit 440, the recognition unit 442, the detection unit 444, and the transmission / reception unit 450 correspond to the control unit 140, the recognition unit 142, the detection unit 144, and the transmission / reception unit 150 illustrated in FIG. Function as.

  The control unit 440 controls the irradiation apparatus 300 to irradiate a plurality of lights on the object from different directions via the transmission / reception unit 450. For example, the irradiation device 300 is installed at a plurality of different positions so that light can be emitted to the object from a plurality of directions, and the control unit 440 controls the plurality of irradiation devices 300 installed at different positions. . The control unit 440 may control the irradiation direction and irradiation timing of a plurality of lights that are irradiated to the object from the plurality of irradiation apparatuses 300.

  The monitoring system 10 may include a plurality of photographing devices 200 that photograph an object. The plurality of imaging devices 200 capture a vehicle traveling on the road, and the controller 440 irradiates the irradiation device 300 while the vehicle is not captured in the plurality of captured images captured by the plurality of imaging devices 200 within a predetermined range. May be irradiated with light. For example, the control unit 440 acquires the captured images captured by the plurality of imaging devices 200, and the vehicle is reflected in the captured image generated by the imaging device 200 installed before the point where the irradiation device 300 is installed. If not, it is determined that the vehicle is not approaching, and the irradiation device 300 is controlled to emit light.

  As described above, in the monitoring system 10, the data management apparatus 400 detects an object based on the image acquired from the imaging apparatus 200, thereby detecting the object using the inexpensive imaging apparatus 200 that cannot analyze the image. be able to.

<Third Embodiment>
[Photographing apparatus 200 controls irradiation apparatus 300]
FIG. 11 shows the configuration of the monitoring system 10 according to the third embodiment. The monitoring system 10 according to the present embodiment includes an imaging device 200 that captures an object and an irradiation device 300 that irradiates the object with light.

  The imaging apparatus 200 includes an imaging unit 210, a control unit 240, a recognition unit 242, a detection unit 244 and a transmission / reception unit 250. The imaging unit 210, the control unit 240, the recognition unit 242, the detection unit 244, and the transmission / reception unit 250 correspond to the imaging unit 110, the control unit 140, the recognition unit 142, the detection unit 144, and the transmission / reception unit 150 illustrated in FIG. It has the function of.

  The control unit 240 controls at least one of timing, direction, and intensity at which the irradiation apparatus 300 irradiates light. The control unit may cause the imaging unit 210 to capture an image in synchronization with the timing at which the irradiation apparatus 300 irradiates light.

  As described above, according to the monitoring system 10 according to the present embodiment, the imaging apparatus 200 controls the irradiation apparatus 300 and analyzes the captured image to detect the object, thereby detecting the object without using the data management apparatus 400. Can be detected.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Monitoring system, 50 ... Communication line, 110 ... Imaging | photography part, 120 ... Acquisition part, 130 ... Irradiation part, 140 ... Control part, 142 ... Recognition part, 144 ... Detection unit 150 ... Transmission / reception unit 170 ... Captured image extraction unit 180 ... Shadow image extraction unit 190 ... Object image extraction unit 200 ... Shooting device 210 ... Image capturing unit, 240 ... control unit, 242 ... recognition unit, 244 ... detection unit, 250 ... transmission / reception unit, 300 ... irradiation device, 400 ... data management device, 440 ... Control unit, 442 ... recognition unit, 444 ... detection unit, 450 ... transmission / reception unit, 500 ... hub, 600 ... monitor

Claims (8)

An acquisition unit that acquires the captured image from an imaging unit that captures an object and generates a captured image;
A control unit that controls an irradiation unit that irradiates a plurality of lights from different directions with respect to the object;
A recognition unit for recognizing an image of a shadow generated by the irradiation unit irradiating the object with the plurality of diffused lights in the captured image;
A detection unit that detects the object based at least on the shadow image recognized by the recognition unit ;
The control unit causes the irradiation unit to further irradiate coherent light from a plurality of directions to the position of the object detected by the detection unit,
The detection unit detects a contour line of the object by connecting positions where the traveling direction of the coherent light irradiated from the plurality of directions changes, and based on the detected contour line, the height and area of the object And a monitoring device for detecting at least one of the volumes . The control unit causes the irradiation unit to irradiate the plurality of lights sequentially from different directions,
The monitoring device
A plurality of photographed images photographed at the timing when the irradiating unit radiates the light; a photographed image extracting unit;
The monitoring apparatus according to claim 1, further comprising: a shadow image extraction unit that extracts the shadow image by comparing the plurality of captured images extracted by the captured image extraction unit.   The monitoring apparatus according to claim 1, wherein the control unit causes the imaging unit to perform imaging in synchronization with a timing at which the irradiation unit irradiates the light. An object image extraction unit that extracts an image of the object from the captured image;
4. The detection unit according to claim 1, wherein the detection unit detects at least one of a height, an area, and a volume of the object based on at least one of the image of the object and the image of the shadow. The monitoring device according to one item. The photographing unit photographs a vehicle traveling on a road,
The monitoring device according to any one of claims 1 to 4 , wherein the irradiation unit irradiates the light while the vehicle is not reflected in the captured image captured by the imaging unit. A photographing device for photographing an object and generating a photographed image;
An irradiation device for irradiating the object with light;
A monitoring system comprising a data management device for analyzing the captured image,
A control unit that controls the irradiation apparatus to irradiate the object with a plurality of light beams from different directions;
A recognition unit that recognizes an image of a shadow generated by the irradiation device irradiating the object with the plurality of diffused lights in the captured image;
A detection unit that detects the object based at least on the shadow image recognized by the recognition unit;
The control unit causes the irradiation device to further irradiate coherent light from a plurality of directions on the position of the object detected by the detection unit,
The detection unit detects a contour line of the object by connecting positions where the traveling direction of the coherent light irradiated from the plurality of directions changes, and based on the detected contour line, the height and area of the object And a monitoring system for detecting at least one of the volumes . A plurality of the photographing devices for photographing the object;
The plurality of photographing devices photograph a vehicle traveling on a road,
The monitoring system according to claim 6 , wherein the control unit causes the irradiation apparatus to irradiate the light while the vehicle is not reflected in the plurality of captured images captured by the plurality of imaging apparatuses within a predetermined range. . A photographing device for photographing an object and generating a photographed image;
A monitoring system comprising: an irradiation device for irradiating the object with light,
The imaging device
A control unit that controls the irradiation apparatus to irradiate the object with a plurality of light beams from different directions;
A recognition unit that recognizes an image of a shadow generated by the irradiation device irradiating the object with the plurality of diffused lights in the captured image;
A detection unit that detects the object based at least on the shadow image recognized by the recognition unit;
The control unit causes the irradiation device to further irradiate coherent light from a plurality of directions on the position of the object detected by the detection unit,
The detection unit detects a contour line of the object by connecting positions where the traveling direction of the coherent light irradiated from the plurality of directions changes, and based on the detected contour line, the height and area of the object And a monitoring system for detecting at least one of the volumes .

Images