JP2010186410A - Passage detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a passage detection device capable of detecting a passing object more precisely with a simple configuration. <P>SOLUTION: The passage detection device for detecting a passing object that passes through a passageway formed between a pair of main bodies opposed to each other comprises a first imaging part that is disposed on the passage side of one of the pair of the main bodies with an elevation angle for taking a first image of a predetermined range on the passage side, and a second imaging part that is disposed in parallel with the first imaging part along the passing direction of the passage with the same elevation angle as the elevation angle of the first imaging part for taking a second image of a predetermined range on the passage side. The passage detection device detects the passage state of the passing object based on the first image taken by the first imaging part, and the second image taken by the second imaging part. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a passage detection device that detects an object passing through a predetermined location, for example.

  Currently, traffic control devices are used to manage traffic of people. The traffic control device is provided, for example, at an entrance / exit of a specific area such as a railway, an airport, or a facility. For example, an automatic ticket gate as a traffic control device reads an information storage medium possessed by a user and determines whether or not the user can pass. If the traffic control device determines that the traffic is allowed, the traffic control device opens the door and prompts the user to pass. If the traffic control device determines that the traffic is not allowed, the traffic control device closes the door to prevent the user from passing.

  In the automatic ticket gate, it is necessary to associate the owner of the information storage medium with the person whose traffic is controlled by the door. For this reason, an automatic ticket gate apparatus provided with a plurality of sensors for detecting the passing states of a user and a moving object on the side surface of the main body is provided (for example, see Patent Document 1).

JP 2008-14171 A

  The automatic ticket gate described above determines for each sensor whether a person or an object exists in the detection area. The automatic ticket gate determines that a person or an object exists when the brightness level acquired by the sensor is equal to or lower than a reference value. These sensors are used to pass through a passage formed by arranging the automatic ticket gates. They are arranged at predetermined intervals along the direction.

  The automatic ticket checker determines that the same person or object is detected by the respective sensors when the brightness below the reference value is detected by the adjacent sensors. As a result, the automatic ticket gate described above detects the position of the moving person or object.

  However, the automatic ticket gate described above includes a plurality of light receiving elements that receive light so as to correspond to a plurality of illumination units arranged. For this reason, when an illuminating unit is added to increase the number of points to be detected, it is necessary to add the same number of light receiving elements as the illuminating unit. For this reason, there exists a problem that cost increases.

  For example, when a plurality of people pass through the passage closely, the automatic ticket gate described above may determine that the plurality of persons are the same person. For this reason, there is a problem that the traffic control cannot be performed accurately.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a passage detection device that can detect passing objects with higher accuracy with a simple configuration.

  A passage detection device according to an embodiment of the present invention is a passage detection device that detects a passing object passing through a passage formed between a pair of main bodies provided facing each other, and one of the pair of main bodies. A first imaging unit that is provided on the passage side of the main body with an elevation angle and that captures a first image in a predetermined range on the passage side; and the first imaging unit that has the same elevation angle as the first imaging unit. A first image captured by the first imaging unit, and a second imaging unit that is installed in parallel along the passage direction of the passage and the passage, and that captures a second image in a predetermined range on the passage side And a detection unit that detects a passing state of the passing object based on a second image captured by the second imaging unit.

  Further, the passage detection device as one embodiment of the present invention is a passage detection device that detects a passing object passing through a passage formed between a pair of main bodies provided facing each other, and the pair of both main bodies. The first imaging unit is provided with an elevation angle on each of the passage sides, and captures a first image in a predetermined range on the passage side, and the first imaging unit with the same elevation angle as the first imaging unit. And a second imaging unit that is arranged in parallel in the passage direction of the section and the passage and is installed in each main body and captures a second image in a predetermined range on the passage side, and is captured by the first imaging unit And a detection unit that detects a passing state of the passing object based on the first image and the second image captured by the second imaging unit.

  A ticket gate as an embodiment of the present invention is a ticket gate for performing ticket gate processing on a user who passes through a passage formed between a pair of main bodies provided facing each other. A first imaging unit that is provided with an elevation angle on the passage side of one of the main bodies and that captures a first image in a predetermined range on the passage side, and has the same elevation angle as the first imaging unit. A first imaging unit and a second imaging unit which are installed in parallel along the passage direction of the passage and which captures a second image in a predetermined range on the passage side, and the first imaging unit captures the second image. Based on a first image and a second image captured by the second imaging unit, a detection unit that detects a passing state of the passing object, a reading unit that reads ticket information from a ticket, and the reading unit A traffic determination unit for determining traffic based on the ticket information read by When it is determined as traffic determination NG by the traffic determination unit, or when a passing object is detected by the detection unit in a state where the ticket information is not read, images are captured by the first imaging unit and the second imaging unit. And a storage unit for storing the first image and the second image.

  According to one aspect of the present invention, it is possible to provide a passage detection device capable of detecting a passing object with higher accuracy with a simple configuration.

FIG. 1 is a block diagram for explaining a configuration example of a passage detection device according to an embodiment. FIG. 2 is an explanatory diagram for explaining an example in which a person passes through a passage formed by the passage detection device shown in FIG. FIG. 3 is a diagram illustrating an overview of the passage detection device illustrated in FIG. 1. FIG. 4 is a top view of a passage formed by a pair of traffic control devices. FIG. 5 is a view of a passage formed by a pair of traffic control devices as viewed from the direction of travel. FIG. 6 is an explanatory diagram for describing an image captured by the traffic control device illustrated in FIG. 1. FIG. 7 is an explanatory diagram for describing image processing for the upper image performed by the image processing unit. FIG. 8 is a top view of a passage formed by a pair of traffic control devices. FIG. 9 is a view of a passage formed by a pair of traffic control devices as viewed from the direction of travel. FIG. 10 is an explanatory diagram for describing image processing for the lower image performed by the image processing unit. FIG. 11 is a top view of a passage formed by a pair of traffic control devices. FIG. 12 is a view of a passage formed by a pair of traffic control devices as viewed from the direction of travel. FIG. 13 is a flowchart for explaining the operation of the traffic control device shown in FIG. FIG. 14 is a flowchart for explaining the upper calculation process shown in FIG. FIG. 15 is a flowchart for explaining the lower-side arithmetic processing shown in FIG. FIG. 16 is a diagram illustrating an overview of another example of the traffic control device. FIG. 17 is a diagram illustrating an overview of still another example of the traffic control device. FIG. 18 is a block diagram for explaining a configuration example of a passage detection device according to another embodiment. FIG. 19 is a top view of a passage formed by the traffic control device shown in FIG. 20 is a view of a passage formed by the traffic control device shown in FIG. 18 as viewed from the direction of travel. FIG. 21 is an explanatory diagram for describing an image captured by the traffic control device illustrated in FIG. 18. FIG. 22 is a top view of a passage formed by the passage detection device according to still another embodiment. 23 is a view of a passage formed by the passage detection device shown in FIG. 22 as viewed from the direction of travel. FIG. 24 is an explanatory diagram for describing an image captured by the traffic control device illustrated in FIGS. 22 and 23. FIG. 25 is a block diagram for explaining a configuration example of a ticket gate according to another embodiment.

  Hereinafter, a passage detection device according to an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram for explaining a configuration example of the passage detection apparatus 100 according to the first embodiment.

  As shown in FIG. 1, the passage detection device 100 includes an illumination unit 1, an illumination control unit 4, an imaging unit 5A, an imaging unit 5B, an imaging control unit 6, an image input unit 7, an image processing unit 8, a control unit 9, and the like. It has. The image input unit 7, the image processing unit 8, and the control unit 9 are connected to each other via a bus 10 or the like.

  FIG. 2 is an explanatory diagram for explaining an example in which a person passes through a passage formed by the pair of main bodies 101 and 102 of the passage detection device 100 shown in FIG.

  FIG. 3 is a diagram illustrating an overview of the passage detection device 100 illustrated in FIG. 1.

  As shown in FIG. 3, the illumination unit 1 is installed on the passage side of one main body 101 of the passage detection device 100. The illumination part 1 is comprised by the Light Emitting Diode (LED) etc. which emit the near infrared light which has directivity, for example. As shown in FIG. 3, the illuminating unit 1 is on the passage side of one main body 101 and below the installation position of the imaging unit 5 along the passage direction of the passage formed by the pair of main bodies 101 and 102. Installed horizontally. That is, the illumination unit 1 emits near infrared light having directivity toward the opposite main body 102 horizontally.

  The illumination unit 1 includes a condenser lens. The light emitted from the illumination unit 1 is collected by a condenser lens. The light emitted from the illuminating unit 1 is in the form of a beam having an irradiation range radius of about several centimeters at the maximum distance (about the width of a passage formed by the pair of main bodies 101 and 102).

  The illumination control unit 4 controls the lighting timing and illumination intensity of the illumination unit 1. The illumination control unit 4 includes, for example, an electric board on which a counter IC is mounted. The illumination control unit 4 controls the timing at which the illumination is turned on by switching between ON and OFF of the current flowing through the illumination unit 1, and can adjust the light emission intensity by adjusting the current value. .

  As shown in FIG. 3, the imaging unit 5 </ b> A and the imaging unit 5 </ b> B are installed with an elevation angle on the passage side of one main body 101 of the passage detection device 100. Each of the imaging unit 5A and the imaging unit 5B includes, for example, a camera including an area image sensor such as a CCD or a CMOS. The imaging unit 5A and the imaging unit 5B form an image of light received by an optical system such as a lens on an area image sensor. Each pixel of the area image sensor converts received light into an electrical signal, that is, an image, and outputs it as a digital signal.

  The imaging unit 5A and the imaging unit 5B are arranged side by side with the same elevation angle in parallel along the passage direction of the passage. That is, the imaging unit 5A and the imaging unit 5B function as a stereo camera. That is, the imaging unit 5 </ b> A and the imaging unit 5 </ b> B acquire a stereo photograph of a passing object that passes through a passage formed by the pair of main bodies 101 and 102.

  The imaging control unit 6 controls the timing of imaging by the imaging unit 5A and the imaging unit 5B. That is, the imaging control unit 6 controls the timing so that the imaging unit 5A and the imaging unit 5B perform imaging simultaneously by sharing the horizontal synchronization signal and the vertical synchronization signal.

  The simultaneity of the imaging control unit 6 can be realized, for example, by distributing a synchronization signal by a pulse generator. In addition, the imaging control unit 6 synchronizes with the illumination control unit 4 and the signal so that the imaging unit 5A and the imaging unit 5B perform imaging in synchronization with the lighting timing of the illumination unit 1 and the imaging unit 5A and the imaging unit 5B. The imaging unit 5B is controlled.

  The imaging control unit 6 controls the gains of the area image sensors of the imaging unit 5A and the imaging unit 5B.

  The image input unit 7 sequentially captures images acquired by the imaging unit 5. The image input unit 7 includes, for example, a memory that temporarily stores an image, a timing signal generation unit, and the like. The timing signal generator generates a timing signal for controlling timing for capturing an image.

  The image processing unit 8 performs various image processing on the image input by the image input unit 7. For example, the image processing unit 8 performs background difference processing, edge detection processing, and the like on the input image. The image processing unit 8 performs binarization processing and labeling processing on the input image. Furthermore, the image processing unit 8 specifies the center of gravity of each area labeled by the labeling process.

  The control unit 9 comprehensively controls the operations of the illumination control unit 4, the imaging control unit 6, and the image processing unit 8. The control unit 9 includes a memory that functions as a storage unit. The memory is composed of, for example, a ROM, a RAM, and a nonvolatile memory. The ROM stores a control program, control data, and the like in advance. The RAM functions as a working memory and temporarily stores data being processed by the control unit 9. The nonvolatile memory stores the processing result of the apparatus.

  The control unit 9 functions as a detection unit. The control unit 9 calculates the distance from the main body of the passage detection device 100 to the passing object and the height of the passing object based on the images captured by the imaging unit 5A and the imaging unit 5B, and passes the passage of the passing object. The width in the direction and the thickness of the passing material between the bodies are detected.

4 and 5 are explanatory diagrams for explaining an example in which an object (person) passes through a passage formed by a pair of main bodies 101 and 102. FIG.
FIG. 4 is a view of a passage formed by the pair of main bodies 101 and 102 as viewed from above.
FIG. 5 is a view of a passage formed by the pair of main bodies 101 and 102 as viewed from the direction of travel.

  As shown in FIGS. 4 and 5, when a passing object exists in the imaging range of the imaging unit 5A and the imaging unit 5B, that is, when a person passes through the passage, it is installed on the passage side of the main body 101. The light emitted from the illuminated lighting unit 1 irradiates the person.

  FIG. 6 is an explanatory diagram for describing an image captured by the passage detection device 100 illustrated in FIGS. 1 to 5. Note that the image illustrated in FIG. 6A is an image captured by the imaging unit 5A illustrated in FIGS. 4 and 5. Further, the image shown in FIG. 6B is an image taken by the imaging unit 5B shown in FIGS.

  As shown in FIGS. 6A and 6B, an image (input image) captured by the imaging unit 5A and the imaging unit 5B and input by the image input unit 7 is 2Nhor in the X-axis direction (lateral direction). And 2Nver pixels in the Y-axis direction (vertical direction). The input image includes a passing object and a bright spot Q generated by irradiating the passing object with light emitted from the illumination unit 1.

  In addition, since there is parallax between the imaging unit 5A and the imaging unit 5B, the position where the passing object appears is shifted between the image captured by the imaging unit 5A and the image captured by the imaging unit 5B. This deviation increases when the passing object is close to the main body 101 and decreases when the passing object is far from the main body 101. That is, the control unit 9 can calculate the distance from the main body of the passage detection device 100 to the passing object and the height of the passing object based on the position where the passing object is reflected in each image.

  Further, as shown in FIGS. 6A and 6B, the input image is divided into an upper image and a lower image at a predetermined position in the Y-axis direction. The imaging unit 5A and the imaging unit 5B are installed with an elevation angle, and the illumination unit 1 is installed so as to emit light horizontally. For this reason, the upper end of the passing object is mainly reflected in the upper image. In addition, the lower image includes a bright spot Q that is generated when a passing object is irradiated by the illumination unit 1.

  Next, a method for calculating the distance from the main body of the passage detection device 100 to the passing object and the height of the passing object will be described in detail. In the present embodiment, a method for obtaining the distance from the apparatus to the passing object using the principle of triangulation will be described, but the method for obtaining the distance may be any other method.

First, processing for an input image will be described.
FIG. 7 is an explanatory diagram for describing processing performed on the upper image of the input image illustrated in FIG. 6.

  The images shown in FIGS. 7A and 7B are upper images in the input image. The image illustrated in FIG. 7A is an upper image in the image captured by the imaging unit 5A. Further, the image shown in FIG. 7B is an upper image in the image captured by the imaging unit 5B.

  The image processing unit 8 performs background difference processing on the upper image. That is, the image processing unit 8 compares the background image captured in advance with the upper image, and extracts pixels having a difference. The image processing unit 8 extracts the image shown in FIG. 7C from the image shown in FIG. 7A by the background difference processing. Similarly, the image processing unit 8 extracts the image shown in FIG. 7D from the image shown in FIG.

  The image processing unit 8 functions as an edge detection processing unit. The image processing unit 8 performs edge detection processing on the image that has been subjected to background difference processing. That is, the image processing unit 8 extracts the outline of the passing object by obtaining a difference from the adjacent pixel for each pixel by using a differential filter such as a SOBEL operator filter. That is, the image processing unit 8 extracts the area of the passing object. By the edge extraction process, the image processing unit 8 extracts the image shown in FIG. 7E from the image shown in FIG. Similarly, the image processing unit 8 extracts the image shown in FIG. 7F from the image shown in FIG.

  Further, the image processing unit 8 functions as a vertex specifying unit. That is, the image processing unit 8 performs a process of specifying the vertex based on the image subjected to the edge detection process. That is, the image processing unit 8 specifies, as vertices, pixels that are not more than a specific threshold and that are the uppermost in the vertical axis direction in the images illustrated in FIGS. 7E and 7F. Thereby, the image processing unit 8 specifies the vertex A in FIG. Similarly, the image processing unit 8 specifies the vertex B in FIG.

  Furthermore, the image processing unit 8 functions as a parallax calculation unit. The image processing unit 8 combines the images shown in FIGS. 7E and 7F as shown in FIG. 7G, and calculates the difference between the vertex A and the vertex B. That is, the image processing unit 8 calculates the distance (number of pixels) N1 between the vertex A and the vertex B in the horizontal axis direction. Further, the image processing unit 8 calculates a distance N2 between the vertexes A and B in the vertical axis direction and the lower side of the upper image. The imaging unit 5A and the imaging unit 5B are installed at the same elevation and the same height. For this reason, the difference in the vertical axis direction between the vertex A and the vertex B is almost zero.

  Next, a method for calculating the distance from the main body of the passage detection device 100 to the passing object based on the parallax of the imaging unit 5A and the imaging unit 5B will be described in detail.

  FIG. 8 is an explanatory diagram for explaining the relationship of the arrangement of the components of the passage detection device 100.

As shown in FIG. 8, the imaging unit 5A and the imaging unit 5B are installed with a distance of Dbase. The angle of view in the horizontal direction of the imaging unit 5A and the imaging unit 5B is θhor. The distance between the main body 101 and the main body 102 is LM. Here, the distance from the main body 101 to the passing object is La. Further, the distance in the passage direction of the passage of the imaging range at this distance La is Dhor. In this case, the distance La can be expressed as the following formula 1.
La = Dhor / (2 tan (θhor / 2)) (Equation 1)
In this case, since 2Nhor and Dhor of the input image correspond to each other and N1 and Dbase correspond to each other, the following Expressions 2 and 3 are established.
Dbase / Dhor = N1 / 2Nhor (Formula 2)
Dhor = (Dbase · 2Nhor) / N1 (Equation 3)
By substituting Equation 3 into Equation 1, the distance La can be expressed as Equation 4 below.
La = (Dbase · Nhor) / (N1 · tan (θhor / 2)) (Equation 4)
θhor and Dbase are constants based on conditions such as the installation state of the imaging unit 5A and the imaging unit 5B. Nhor / N1 is a value obtained from the upper image. For this reason, the control unit 9 of the passage detection device 100 can calculate the horizontal distance La from the main body 101 to the passing object based on the upper image.

  Next, a method for calculating the height of a passing object based on images captured by the imaging unit 5A and the imaging unit 5B will be described in detail.

  FIG. 9 is an explanatory diagram for explaining the arrangement relationship of the components of the passage detection device 100.

  As shown in FIG. 9, the imaging unit 5A and the imaging unit 5B are installed at a height in the vertical direction Dcam. The angles of view in the vertical direction of the imaging unit 5A and the imaging unit 5B are each θver. The imaging unit 5A and the imaging unit 5B are installed such that the optical axis has an elevation angle of θel with respect to the horizontal.

  Here, the distance to the point F in the optical axis direction of the imaging unit 5A and the imaging unit 5B is Lc. A surface in a direction orthogonal to the optical axis direction of the imaging unit 5A and the imaging unit 5B at the distance Lc is defined as a frame surface. In this frame plane, the distance between the vertices A and B and the optical axes of the imaging units 5A and 5B is Dx. Furthermore, let R be a point where a straight line that forms an angle of 1 / 2θver with the optical axes of the imaging unit 5A and the imaging unit 5B and the frame surface intersect. In this case, the distance between the point R and the point F (distance that is 1/2 of the image frame width in the vertical direction) is Dver.

When each part is arranged in the above relationship, Nver and Dver of the input image correspond to each other, and N2 and Dx correspond to each other.
Dver / Dx = N2 / Nver (Formula 5)
Further, Dver can be expressed as the following Expression 6.
Dver = tan (θver / 2) · Lc (Expression 6)
Here, Lc can be expressed as Equation 7 below.
Lc = Dxtan θel + La / cos θel (Expression 7)
When Expression 7 is substituted into Expression 6, the following Expression 8 is obtained.
Dver = tan (θver / 2) · (Dxtanθel + La / cosθel)
... (Formula 8)
When Equation 8 is substituted into Equation 5 and solved for Dx, the following Equation 9 is obtained.

Further, the height Dt of the passing object can be expressed as the following Expression 10.
Dt = Dcam + La · tan θel + Dx / cos θel (Equation 10)
θver, θel, and Dcam are constants based on conditions such as the installation state of the imaging unit 5A and the imaging unit 5B. Nver / N2 is a value obtained from the upper image. Therefore, the control unit 9 of the passage detection device 100 can calculate the height Dt of the passing object by substituting Dx obtained by Equation 9 into Equation 10.

  As described above, the control unit 9 of the passage detection device 100 detects the vertex A and the vertex B based on the images captured by the imaging unit 5A and the imaging unit 5B. The control unit 9 can calculate the distance La between the main body 101 and the passing object and the height Dt of the passing object based on the installation conditions of the imaging unit 5A and the imaging unit 5B and the coordinates of the vertex A and the vertex B. it can.

  In the automatic ticket gate, it is determined that a person whose height is 125 cm or more is an adult. In this case, the control unit 9 determines whether or not Dt is 125 cm or more, and determines whether or not the passing object (person) is an adult.

  Next, another method for calculating the distance from the main body of the passage detection device 100 to the passing object will be described in detail.

First, processing for an input image will be described.
FIG. 10 is an explanatory diagram for describing processing performed on the lower image of the input image illustrated in FIG. 6.

  FIG. 10A is a diagram illustrating an example of a lower image of an image captured by the imaging unit 5A or the imaging unit 5B.

  The image processing unit 8 performs binarization processing on the lower image. That is, the image processing unit 8 compares a threshold value stored in a memory (not shown) with the value of each pixel of the lower image, and “0 (dark)” is set for pixels that are less than the threshold value, and “1” is set for pixels that are equal to or greater than the threshold value. (Ming) ”.

  Here, a threshold value is set in the memory such that a portion where the irradiation light from the illumination unit 1 is reflected by a passing object passing through the passage becomes “bright” and other portions become “dark”. ing. By the above binarization process, the image processing unit 8 extracts an image as shown in FIG. 10B from the image shown in FIG.

  The image processing unit 8 performs a labeling process on the binarized image. That is, the image processing unit 8 finds one pixel that is “bright” in the image shown in FIG. 10B and has no label added, and adds a label. The image processing unit 8 adds the same label to the “bright” pixels among the four neighboring pixels connected to the labeled pixels.

  By performing this process on the entire image, “bright” regions (bright spots) are classified as groups. By the above labeling process, data as shown in FIG. 10C is obtained. FIG. 10C is a diagram illustrating an example of label information added to each pixel by the labeling process. In the figure, three areas are detected as illumination positions.

  In the present embodiment, the labeling process is performed so as to add a label to pixels in the vicinity of four “bright” pixels. However, the present invention is not limited to this. The labeling process may be performed in any range. Since the pixels may vary depending on the size of the illumination, the uniformity of the illumination light, the influence of noise, etc., the range for the labeling process should be set as appropriate, for example, around 8 pixels or around 24 pixels. Can do.

  Further, the image processing unit 8 performs a centroid calculation process for calculating the centroid of each group based on the image on which the labeling process has been performed. That is, the image processing unit 8 obtains the coordinates (center of gravity) of the center of each illumination based on the coordinates and the number of pixels of each pixel in the area.

FIG. 10D is a diagram illustrating one region classified by the labeling process. As shown in FIG. 10D, there are five pixels in the classified area. When the coordinates of the center of gravity of this area are (Xc, Yc), the coordinates of each pixel in the area are (Xi, Yi), and the number of pixels in the area is n, the following Expressions 11 and 12 hold.

  The center of gravity (Xc, Yc) can be specified by Expressions 11 and 12 above. The image processing unit 8 calculates a distance N3 in the X-axis direction between the specified center of gravity and the upper center point M of the lower image. Further, the image processing unit 8 calculates a distance N4 in the Y-axis direction between the specified center of gravity and the upper center point M of the lower image.

  Next, a method for calculating the distance from the main body of the passage detection device 100 to the passing object based on the lower image will be described in detail.

  FIG. 11 is an explanatory diagram for explaining the arrangement relationship of the components of the passage detection device 100. Here, the description is based on the assumption that the distance from the main body of the passage detection device 100 to the passing object is calculated based on the image captured by the imaging unit 5A. However, even when the distance from the main body of the passage detection device 100 to the passing object is calculated based on the image picked up by the image pickup unit 5B, the same result can be obtained by the same processing.

  As shown in FIG. 11, the imaging unit 5A and the illumination unit 1 are installed with a distance of Ws in the passage direction of the passage. The illuminating unit 1 is one of a plurality of illuminating units 1 installed on the passage side of the main body 101, and the optical axis thereof is different from the optical axis of the imaging unit 5A in the passage direction of the passage. To do.

The angle of view in the horizontal direction of the imaging unit 5A is θhor. The distance between the main body 101 and the main body 102 is LM. In addition, an angle formed by a line connecting the portion (bright spot) Q irradiated with light from the illumination unit 1 in the passing object and the imaging unit 5A and the optical axis of the imaging unit 5A is defined as θa. Further, when the distance in the horizontal direction between the imaging unit 5 and the illumination position Q is La, the following Expression 13 is established.
tan θa = Ws / La (Formula 13)
Here, a distance to a point F in the optical axis direction of the imaging unit 5A is Lc, and a plane perpendicular to the optical axis direction at the distance Lc is a frame plane. Further, a point where an extension line of the line connecting the imaging unit 5A and the point Q and the frame surface intersect is defined as Q ′. In this case, the distance Wa between the point Q ′ and the point F is expressed as the following Expression 14.
Wa = Lc · tan θa (Formula 14)
Here, S is a point where a straight line forming an angle of 1 / 2θhor with the optical axis of the imaging unit 5A intersects the frame surface. In this case, the distance between the point S and the point F (a distance that is ½ of the image frame width in the vertical direction) Whor is expressed as Equation 15 below.
Whor = Lc · tan (θhor / 2) (Formula 15)
In this case, since Nhor and Whor of the input image correspond to each other and N3 and Wa correspond to each other, the following Expression 16 is established.
Wa / Wor = N3 / Nhor (Expression 16)
When Equations 13 to 16 are solved for La, the following Equation 17 is obtained.
La = Ws · Nhor / N3 · tan (θhor / 2) (Expression 17)
θhor and Ws are constants based on conditions such as the installation state of the illumination unit 1 and the imaging unit 5A. N3 / Nhor is a value obtained from the image. For this reason, the control unit 9 of the passage detection device 100 can calculate the horizontal distance La from the main body 101 to the passing object based on the image acquired by the imaging unit 5A.

  Next, another method for calculating the distance of the passing object from the main body of the passage detection device 100 based on the lower image will be described in detail.

  FIG. 12 is an explanatory diagram for explaining the arrangement relationship of the components of the passage detection device 100.

  As shown in FIG. 12, the imaging unit 5A and the imaging unit 5B are installed at a height in the vertical direction Dcam. The angles of view in the vertical direction of the imaging unit 5A and the imaging unit 5B are each θver. The imaging unit 5A and the imaging unit 5B are installed such that the optical axis has an elevation angle of θel with respect to the horizontal. In addition, the illumination unit 1 is disposed below the imaging unit 5A and the imaging unit 5B by a distance of Ds. In addition, an angle formed by a line connecting a portion (bright spot) Q irradiated with light from the illumination unit 1 and the imaging unit 5A in the passing object and the horizontal is θa.

Here, the distance to the point F in the optical axis direction of the imaging unit 5A and the imaging unit 5B is Lc. A surface in a direction orthogonal to the optical axis direction of the imaging unit 5A and the imaging unit 5B at the distance Lc is defined as a frame surface. Also, let Q ′ be the line where the extension line of the line connecting the imaging unit 5A and the imaging unit 5B and the bright spot Q intersects the frame surface. Here, when the distance between the point F and the point Q ′ is Da, Da can be expressed by the following Expression 18.
Da = Lc · tan (θel + θa) (Formula 18)
Here, let R be the point where a straight line that forms an angle of 1 / 2θver with the optical axes of the imaging unit 5A and the imaging unit 5B and the frame plane intersect. In this case, the distance Dver between the point R and the point F (distance that is ½ of the image frame width in the vertical direction) Dver is expressed as the following Expression 19.
Dver = Lc · (θver / 2) (Equation 19)
In this case, since Nver and Dver of the input image correspond to each other and N4 and Da correspond to each other, the following Expression 20 is established.
Da / Dver = N4 / Nver (Equation 20)
When Equations 18 to 20 are solved for La, the following Equation 21 is obtained.
La = Ds · (C · tan θel + 1) / (C−tan θel) (Formula 21)
C is expressed by the following formula 22.
C = N2 · tan (θver / 2) / Nver (Equation 22)
θel, θver, and Ds are constants based on conditions such as the installation state of the illumination unit 1, the imaging unit 5A, and the imaging unit 5B. N4 / Nver is a value obtained from the image. Therefore, the control unit 9 of the passage detection device 100 calculates a distance La (horizontal distance to the bright spot Q) La from the main body 101 based on the image acquired by the imaging unit 5A or the imaging unit 5B. can do.

  As described above, the control unit 9 of the passage detection device 100 specifies the barycentric point of the bright spot Q based on the image captured by the imaging unit 5A or the imaging unit 5B. The control unit 9 calculates the distance La between the main body 101 and the passing object based on the coordinates of the center of gravity of the specified bright spot Q and the installation conditions of the imaging unit 5A, the imaging unit 5B, and the illumination unit 1. Can do.

  The angles of the optical axes of the imaging units 5A and 5B may be arranged at any angle as long as they do not intersect with the optical axis of the illumination unit 1 at least.

  Further, as described above, by calculating the distance La from both sides of the pair of main bodies 101 and 102, it is possible to calculate the thickness Lw of the passing material between the main bodies. That is, when the distance from one main body 101 to the passing object is La1, the distance from the other main body 102 to the passing object is La2, and the distance between the pair of main bodies 101 and the main body 102 is LM, The thickness Lw in the direction between the main bodies can be obtained by the equation Lw = LM− (La1 + La2). Thereby, for example, it is possible to prevent a person having a small thickness such as a bag from being mistaken as a person.

  As described above, the example in which the distance from the main body to the passing object is calculated by two methods for the same illumination has been described, but the distance may not be calculated accurately. For example, when the interval between bright spots is narrow, or when the illumination unit 1 is continuous illumination, it is not possible to associate the distance to the object with the position in the horizontal direction. Accordingly, La can be calculated using the method described in FIG. 12, and Ws can be back calculated by the following formula 23 to use the method shown in FIG. 11 to accurately calculate the distance La.

Ws = N3 · tan (θhor / 2) · La / Nhor (Equation 23)
FIG. 13 is a flowchart for explaining the operation of the passage detection apparatus 100 shown in FIG.
First, the passage detection device 100 acquires an image within an angle of view by the imaging unit 5A and the imaging unit 5B (step S11). The image processing unit 8 and the control unit 9 of the passage detection device 100 divide the acquired image into an upper image and a lower image (step S12).

  The image processing unit 8 and the control unit 9 perform upper calculation processing on the upper image (step S13). Further, the image processing unit 8 and the control unit 9 perform a lower calculation process on the lower image (step S14). That is, the control unit 9 calculates the distance La and the height Dt by the upper calculation process and the lower calculation process.

  The control unit 9 writes the processing results (distance La and height Dt) of the upper calculation process and the lower calculation process to the RAM (random access memory) in the image processing unit 8 (step S15), and ends the process.

FIG. 14 is a flowchart for explaining the upper calculation process shown in FIG.
The image processing unit 8 of the passage detection device 100 performs background difference processing on the upper image (step S21). That is, the image processing unit 8 compares the background image captured in advance with the upper image, and extracts pixels having a difference.

  The image processing unit 8 performs edge detection processing on the image that has been subjected to background difference processing (step S22). That is, the image processing unit 8 extracts the outline of the passing object by obtaining a difference from the adjacent pixel for each pixel by, for example, differentiation processing.

  The image processing unit 8 performs a process of specifying a vertex based on the image subjected to the edge detection process (step S23). That is, the image processing unit 8 specifies, as an apex, a pixel that is equal to or higher than a specific threshold and that is uppermost in the vertical axis direction in the image subjected to the edge detection process. Note that the image processing unit 8 specifies a vertex in each of the image captured by the imaging unit 5A and the image captured by the imaging unit 5A.

  Next, the control unit 9 of the passage detection device 100 calculates the difference between the coordinates of the vertices of each identified upper image, and calculates the distance La between the main body 101 and the passing object based on the calculated difference (step S24). .

  Further, the control unit 9 of the passage detection device 100 calculates the vertex height Dt based on the coordinate height of the vertex of each identified upper image (step S25).

FIG. 15 is a flowchart for explaining the lower-side arithmetic processing shown in FIG.
The image processing unit 8 of the passage detection device 100 performs binarization processing on the lower image (step S31). In other words, the image processing unit 8 compares the threshold value with the value of each pixel of the input image, and replaces the pixels below the threshold value with “dark” and the pixels above the threshold value with “light”.

  The image processing unit 8 performs a labeling process on the binarized image (step S32). That is, the image processing unit 8 performs the process of attaching the same label to adjacent “bright” pixels on the entire image subjected to the binarization process.

  The image processing unit 8 performs a centroid calculation process for calculating the centroid point of each group based on the image subjected to the labeling process (step S33). That is, the image processing unit 8 obtains the coordinates (centroid point) of the center of the bright spot Q based on the coordinates and the number of pixels of each pixel in the region.

  Next, the control unit 9 of the passage detection device 100 calculates the distance La between the main body 101 and the passing object based on the calculated coordinates of the center of gravity of the bright spot Q (step S34).

  As described above, the passage detection device 100 can perform the upper calculation process and the lower calculation process based on the images captured by the imaging unit 5A and the imaging unit 5B, and obtain the distance La between the main body and the passing object. As a result, it is possible to provide a passage detection device capable of detecting a passing object with higher accuracy with a simple configuration.

  In the above-described embodiment, the passage detection device 100 has been described as including the imaging unit 5A and the imaging unit 5B provided with a predetermined interval, and the illumination units 1 arranged in a plurality horizontally. However, it is not limited to this configuration. For example, the number of illumination units 1 may be further increased.

  FIG. 16 is a diagram illustrating an overview of another example of the passage detection device 100. As illustrated in FIG. 16, the passage detection device 100 includes a plurality of rows of illumination units 1. In other words, the passage detection device 100 includes a plurality of illumination units 1 that are horizontally arranged at different heights. Thus, by arranging the illumination units 1 in a plurality of rows, the passage detection device 100 can detect the distance to the passing object at different heights.

  FIG. 17 is a diagram illustrating an overview of still another example of the passage detection device 100. As illustrated in FIG. 17, the passage detection device 100 includes a line-shaped continuous parallel illumination 11 as an illumination unit. By using the parallel illumination 11 as the illumination unit in this way, the horizontal resolution can be increased.

  Next, the passage detection apparatus according to the second embodiment of the present invention will be described in detail.

  FIG. 18 is a block diagram for explaining a configuration example of the passage detection apparatus 100 according to the second embodiment. The same reference numerals are given to the same components as those of the passage detection device 100 of the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 18, the passage detection device 100 includes an illumination unit 1, an illumination unit 2, an illumination control unit 4, an imaging unit 5A, an imaging unit 5B, an imaging control unit 6, an image input unit 7, an image processing unit 8, and A control unit 9 and the like are provided. The image input unit 7, the image processing unit 8, and the control unit 9 are connected to each other via a bus 10 or the like.

  The illumination unit 1 described in the first embodiment is referred to as the first illumination unit 1, and the illumination unit 2 added in the present embodiment is distinguished as the second illumination unit 2.

  As shown in FIGS. 19 and 20, a plurality of second illumination units 2 are arranged horizontally on the passage side of the other main body 102 opposite to the main body 101 on which the imaging unit 5A and the imaging unit 5B are installed. Installed in a state. The 2nd illumination part 2 is comprised by LED etc. which emit near-infrared light, for example. Moreover, the 2nd illumination part 2 is provided with the diffusion plate which is not shown in figure. That is, the light emitted from the LED is diffused by the diffusion plate and is incident on the imaging unit 5A and the imaging unit 5B installed on one main body 101.

  The first illuminating unit 1 and the second illuminating unit 2 are arranged in the height direction so that the illumination from the first illuminating unit 1 does not hit the light exit of the second illuminating unit 2 or , Are displaced from each other in the horizontal direction. Or you may shift the lighting timing of the illumination of the 1st illumination part 1 and the 2nd illumination part 2 mutually, without shifting an installation position.

  FIG. 21 is an explanatory diagram for describing images captured by the imaging unit 5A and the imaging unit 5B of the passage detection device 100 illustrated in FIG. The image illustrated in FIG. 21A is an image captured by the imaging unit 5A. In addition, the image illustrated in FIG. 21B is an image captured by the imaging unit 5B.

  As shown in FIG. 21, the lower image of this embodiment includes the bright spot Q by the first illumination unit 1 described in the first embodiment. Furthermore, the bright spot S by the second illumination unit 2 is reflected in the lower image of the present embodiment.

  The bright spot S by the second illumination unit 2 always appears in the same position. However, when a passing object exists between the second illumination unit 2 and the imaging unit 5A and the imaging unit 5B, the light from the second illumination unit 2 is blocked, so that the bright spot S does not appear. The control unit 9 detects the presence or absence of a passing object based on whether or not the bright spot S exists at a predetermined position in the image. That is, when it is determined that the bright spot S exists at a predetermined position, the control unit 9 determines that there is no passing object in the passage. Further, when the control unit 9 determines that the bright spot S does not exist at the predetermined position, the control unit 9 determines that there is a passing object in the passage.

  In addition, when determining whether or not the bright spot S exists at a predetermined position for one pixel, an accurate determination may not be performed due to noise. Therefore, the presence / absence of the bright spot S may be determined based on an average value of a plurality of (for example, 8 neighboring) pixels in the vicinity of the position coordinate of the illumination to be determined.

  With this configuration, it is possible to detect a passing object that cannot be detected by illumination from the first illumination unit 1, such as a passing object with low reflectance. As a result, it is possible to provide a passage detection device that can detect passing objects with a simple configuration with higher accuracy.

  In the first and second embodiments described above, the one-side main body 101 is described as including the illumination unit 1, the imaging unit 5A, and the imaging unit 5B. However, the present invention is not limited to this. Both main bodies 101 and 102 of the passage detection device 100 that form the passage may include the illumination unit 1, the imaging unit 5A, and the imaging unit 5B, respectively.

  22 to 24 are explanatory diagrams for describing an example in which both main bodies 101 and 102 of the passage detection device 100 forming the passage include the illumination unit 1, the imaging unit 5A, and the imaging unit 5B, respectively.

  FIG. 22 is a diagram for explaining a function of each main body by disassembling a view of a passage formed by the pair of main bodies 101 and 102 as viewed from above. FIG. 23 is a diagram for explaining the passage formed by the pair of main bodies 101 and 102 as seen from the direction of travel, with the functions of the main bodies disassembled.

  As shown in FIGS. 22 and 23, one main body (first main body) 101 of the passage detection device 100 includes an illumination unit 1, an imaging unit 5A, and an imaging unit 5B. The other main body (second main body) 102 of the passage detection device 100 also includes the illumination unit 1, the imaging unit 5A, and the imaging unit 5B.

  As shown in FIGS. 22 and 23, the passing object exists within the imaging range of the imaging unit 5A and the imaging unit 5B. For this reason, the light inject | emitted from the illumination part 1 installed in multiple numbers by the channel | path side of the main body 101 and the main body 102 is reflected by a passing material.

  Here, for example, when it is assumed that the distance La1 between the passing object and the main body 101 is longer than the distance La2 between the passing object and the main body 102, images as shown in FIGS. 24A to 24D are captured. The

  FIG. 24 is an explanatory diagram for describing an example of an image captured by the imaging unit 5A and the imaging unit 5B of the passage detection device 100 illustrated in FIGS. 22 and 23.

  FIG. 24A shows an image captured by the imaging unit 5A of the main body 101. FIG. As shown in FIG. 24A, a passing object is reflected at a position on the right side of the image. FIG. 24B is an image captured by the imaging unit 5B of the main body 101. As shown in FIG. 24B, a passing object is reflected at a position on the left side of the image.

  FIG. 24C is an image captured by the imaging unit 5A of the main body 102. As shown in FIG. 24C, a passing object is reflected at a position on the left side of the image. FIG. 24D is an image captured by the imaging unit 5B of the main body 102. As shown in FIG. 24D, a passing object is reflected at a position on the right side of the image.

  In the example shown in FIG. 24C and FIG. 24D, since the passing object is closer to the main body than in the example shown in FIG. 24A and FIG. 24B, the passing object is reflected larger. . In addition, the bright spot Q is reflected in the lower part of the lower image as compared with the example shown in FIGS. 24 (A) and 24 (B).

  As described above, the illumination unit 1, the imaging unit 5 </ b> A, and the imaging unit 5 </ b> B are installed in both main bodies of the passage detection device 100 that forms a passage. Thereby, the distance to a passing thing is computable from the main body of both sides. The passage detection device 100 can detect the thickness of the passing object in the direction between the main bodies.

Next, a third embodiment in which the above passage detection device is used as a ticket gate will be described.
FIG. 25 is a block diagram for explaining a configuration example of the ticket gate 200. The same reference numerals are given to the same components as those of the passage detection device 100 of the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 25, the ticket gate 200 includes an illumination unit 1, an illumination control unit 4, an imaging unit 5A, an imaging unit 5B, an imaging control unit 6, an image input unit 7, an image processing unit 8, a control unit 9, and a ticket. A processing unit 12, a door control unit 13, a display unit 14, and the like are provided. The ticket gate 200 is provided with a door (not shown).

  The ticket gate 200 is installed at a ticket gate of a station and performs a ticket gate process on a ticket (IC card or magnetic ticket) possessed by a user at the ticket gate.

  When functioning as the ticket gate 200, the control unit 9 stores a program for calculating a fare in the memory, fare information necessary for the fare calculation process, and the like.

  The ticket processing unit 12 is a reading unit that reads ticket information from a magnetic ticket or an IC card (portable electronic device) that functions as a ticket. The ticket processing unit 12 reads money amount information, boarding station information, and the like as ticket information. When updating ticket information, the ticket processing unit 12 transmits write data and a write command to the IC card.

  The door control unit 13 functions as a traffic control unit. The door control part 13 controls a user's passage. The door control unit 13 includes, for example, a door opening / closing mechanism (not shown) that controls a door that prevents a user from passing. The door is installed so as to close a passage formed by a pair of main bodies of the ticket gate 200. The door control unit 13 controls the opening and closing of the door based on the determination shown in the first and second embodiments by the control unit 9 and the result of the ticket gate process.

  That is, the control unit 9 calculates a fare based on the ticket information read by the ticket processing unit 12. The control unit 9 performs a ticket gate process for determining whether or not the user can pass based on the calculated fare and the amount information of the ticket information. That is, in this case, the control unit 9 functions as a traffic determination unit.

  When the determination is NG as a result of the ticket gate process by the control unit 9, the door control unit 13 performs control to close the door. Further, when the ticket information is not read by the ticket processing unit 12 and the control unit 9 determines that there is a passing object in the passage formed by the main body of the ticket gate 200, the control is performed to close the door. . Further, the door control unit 13 performs control to open the door when the determination is OK as a result of the ticket gate process by the control unit 9.

  The display unit 14 includes a display device that displays guidance information to the user, the result of the ticket gate processing, and the like.

  The control unit 9 includes a history storage unit 9a. The history storage unit 9a is a storage unit that stores images and processing results in association with each other. As described above, when the result of the ticket gate process is NG, or when a passing object is detected in a state where the ticket information is not read, the control unit 9 uses the images captured by the imaging units 5A and 5B as the history. Save in the history storage unit 9a. With this configuration, the face image of the unauthorized user can be stored in the history storage unit 9a as a stereo photograph. As a result, a ticket gate with higher security can be realized with a simple configuration.

  In addition, this invention is not limited to the said embodiment as it is, It can implement by changing a component in the range which does not deviate from the summary in an implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

  DESCRIPTION OF SYMBOLS 1 ... Illumination part, 2 ... Illumination part, 4 ... Illumination control part, 5A ... Imaging part, 5B ... Imaging part, 6 ... Imaging control part, 7 ... Image input part, 8 ... Image processing part, 9 ... Control part, 10 DESCRIPTION OF SYMBOLS ... Bus, 11 ... Parallel illumination, 12 ... Passage ticket processing part, 13 ... Door control part, 14 ... Display part, 100 ... Passage detection apparatus, 101 ... Main body, 102 ... Main body, 200 ... Ticket gate.

Claims (10)

A passage detection device that detects a passing substance passing through a passage formed between a pair of main bodies provided facing each other,
A first imaging unit that is provided with an elevation angle on the passage side of one of the pair of main bodies, and that captures a first image in a predetermined range on the passage side;
The second imaging unit is installed in parallel with the first imaging unit in the passage direction of the passage with the same elevation angle as the first imaging unit, and captures a second image in a predetermined range on the passage side. An imaging unit;
A detection unit that detects a passing state of the passing object based on a first image captured by the first imaging unit and a second image captured by the second imaging unit;
A passage detection device comprising: An edge detection processing unit that extracts outlines of passing objects from the first image captured by the first imaging unit and the second image captured by the second imaging unit;
A vertex identifying unit that identifies the first vertex and the second coordinate based on the outline of the passing object detected by the edge detection processing unit;
A parallax calculation unit that calculates a distance in a horizontal axis direction between the first vertex in the first image and the second vertex in the second image;
Further comprising
The detection unit detects a distance between the main body and the passing object based on a distance between the first vertex and the second vertex calculated by the parallax calculation unit;
The passage detection apparatus according to claim 1.   The detection unit detects the height of the passing object based on the vertical axis coordinates of the first vertex and the second vertex and the detected distance between the main body and the passing object. The passage detection device according to claim 2. A plurality of illuminating units installed along the passage direction of the passage below the first and second imaging units at an angle at which light is emitted horizontally;
The detection unit is based on any one of coordinates of a plurality of bright spots illuminated by the plurality of illumination units reflected in the images captured by the first and second imaging units, The passage detection apparatus according to claim 1, wherein a horizontal distance from the main body to a bright spot is detected. The main body in which the first and second imaging units are installed is provided in plural along the passage direction of the passage on the passage side of the other main body and illuminates the one main body with light. Further comprising
The detection unit includes a passing object in the passage based on the first image captured by the first and second imaging units or the coordinates of the bright spot illuminated by the illumination unit in the second image. The passage detection device according to claim 1, wherein the passage detection device detects whether or not. A passage detection device that detects a passing substance passing through a passage formed between a pair of main bodies provided facing each other,
A first imaging unit that is provided with an elevation angle on the passage side of both of the pair of main bodies, and that captures a first image of a predetermined range on each of the passage sides;
The first imaging unit having the same elevation angle as that of the first imaging unit and arranged in parallel in the passage direction of the passage and installed in each main body, captures a second image in a predetermined range on the passage side A second imaging unit that
A detection unit that detects a passing state of the passing object based on a first image captured by the first imaging unit and a second image captured by the second imaging unit;
A passage detection device comprising: An edge detection processing unit for extracting outlines of passing objects from the first image and the second image captured by the first imaging unit and the second imaging unit installed in the same main body;
A vertex identifying unit that identifies the first vertex and the second coordinate based on the outline of the passing object detected by the edge detection processing unit;
A parallax calculation unit that calculates a distance in a horizontal axis direction between the first vertex in the first image and the second vertex in the second image;
Further comprising
The detection unit detects a distance between the main body and the passing object based on a distance between the first vertex and the second vertex calculated by the parallax calculation unit;
The passage detection device according to claim 6.   The said detection part detects the thickness of the passing material of the direction between main bodies based on the distance from each detected said main body to a passing material, and the distance between said pair of main bodies. The passage detection device described.   The detection unit detects the height of the passing object based on the vertical axis coordinates of the first vertex and the second vertex and the detected distance between the main body and the passing object. The passage detection device according to claim 7. A ticket gate machine that performs ticket gate processing on a user who passes through a passage formed between a pair of main bodies provided facing each other,
A first imaging unit that is provided with an elevation angle on the passage side of one of the pair of main bodies, and that captures a first image in a predetermined range on the passage side;
The second imaging unit is installed in parallel with the first imaging unit in the passage direction of the passage with the same elevation angle as the first imaging unit, and captures a second image in a predetermined range on the passage side. An imaging unit;
A detection unit that detects a passing state of the passing object based on a first image captured by the first imaging unit and a second image captured by the second imaging unit;
A reading unit for reading the ticket information from the ticket;
A traffic determination unit that performs traffic determination based on the ticket information read by the reading unit;
When the passage determination unit determines that the traffic determination is NG, or when a passing object is detected by the detection unit without reading the ticket information, the first imaging unit and the second imaging unit capture images. A storage unit for storing the first image and the second image,
A ticket gate characterized by comprising:

Images