JP2013175131A - Image type vehicle sensor and vehicle sensing program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image type vehicle sensor and a vehicle sensing program capable of reducing interruption of a process for sensing a vehicle.SOLUTION: An image type vehicle sensor 1 comprises a first image sensing process section 32, a second image sensing process section 34 and a selection section 35. The first image sensing process section 32 executes a sensing process for each vehicle on the basis of first image data acquired by photographing a vehicle travelling in a first measurement area of a road. The second image sensing process section 34 executes a sensing process for each vehicle on the basis of second image data acquired by photographing each vehicle after passing through the first measurement area. The selection section 35 is capable of selecting which one is output, from a sensing process result in the first image sensing process section 32 or a sensing process result in the second image sensing process section 34.

Description

  The present invention relates to an image-type vehicle detector and a vehicle detection program for performing vehicle detection processing based on image data obtained by photographing a vehicle traveling on a road.

  Japanese Patent Laid-Open No. 2000-99877 (Patent Document 1) discloses an image type vehicle detector. This detector installs a camera for each lane and digitizes the vehicle image for each lane. And a processing part analyzes the digital image | video for every lane, and measures the number of vehicles and vehicle speed for every lane.

JP 2000-99877 A ([Summary])

  In the configuration described in Patent Document 1, the lens is prevented from being stained by applying a photocatalyst to the lens of the camera. However, it is impossible to completely prevent the lens from becoming dirty. For this reason, it is necessary to periodically clean the lens of the camera. During this cleaning operation, the lens is wiped with a cleaning member such as a cloth. For this reason, while the cleaning work is being performed, the camera on which the cleaning work is being performed cannot shoot the vehicle. That is, the photographing process for detecting the vehicle is interrupted.

  In the configuration described in Patent Document 1, a camera is installed for each lane, but the shooting range of each camera is different. Thus, for example, a camera that captures the right lane cannot capture a vehicle traveling in the left lane. For this reason, a plurality of cameras are not configured to supplement the shooting process, and the above-described interruption of the shooting process cannot be prevented.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an image type vehicle sensor and a vehicle detection program that can suppress interruption of processing for detecting a vehicle.

  (1) In order to solve the above-described problem, an image-type vehicle detector according to an aspect of the present invention photographs one or a plurality of vehicles passing through a first measurement area on a road along a predetermined traveling direction. A first processing unit capable of performing a sensing process for each of the vehicles based on the first image data obtained in step 2; and a second of the roads to which the vehicles have passed through the first measurement area. Based on the second image data obtained by photographing the measurement area, a second processing unit capable of performing sensing processing of each vehicle, a sensing processing result in the first processing unit, and the second A selection unit capable of selecting which of the sensing processing results in the processing unit is to be output.

  According to such a configuration, even if it is in a state in which vehicle detection cannot be performed for one of the first image data and the second image data, the vehicle detection process is performed using the other image data. It can be performed. Thereby, the interruption of the process for detecting a vehicle can be suppressed. For example, the second image data can be obtained by using the photographing unit for obtaining the second image data even when the photographing operation for obtaining the first image data is performed. Similarly, for example, even when a cleaning operation is performed on an imaging unit for obtaining the second image data, the first image data can be obtained using the imaging unit for obtaining the first image data. Accordingly, it is possible to realize an image type vehicle detector that can suppress interruption of processing for detecting the vehicle.

  (2) Preferably, the first processing unit and the second processing unit are capable of performing sensing processing of each vehicle in parallel, and the selection unit is configured to perform sensing processing results in the first processing unit. And any of the sensing processing results in the second processing unit can be output.

  As a result, it is possible to more quickly switch from the state in which the sensing processing result by one processing unit is output to the state in which the sensing processing result by the other processing unit is output. As a result, it is possible to reduce the loss of the vehicle sensing process result.

  (3) Preferably, the first processing unit and the second processing unit are configured by one processing unit, and the selection unit transmits the first image data and the first processing unit to the one processing unit. Based on which of the two image data, it is possible to instruct whether to perform the sensing process for each vehicle.

  As a result, both the vehicle sensing process using the first image data and the vehicle sensing process using the second image data can be performed by one processing unit. Therefore, the manufacturing cost of the image type vehicle sensor can be further reduced.

  (4) Preferably, an image data output unit that outputs at least one of the first image data and the second image data is further provided.

  Thereby, at least one of the first image data and the second image data can be output to, for example, a traffic control center. As a result, an image of the road can be shown on a monitor of a traffic control center. As a result, at least one of the first image data and the second image data obtained by photographing for vehicle sensing can also be used for road monitoring by an operator's visual observation. Thereby, for example, when an accident occurs on a road, the road condition can be confirmed for at least one of the first measurement area and the second measurement area. Thereby, the first image data and the second image data can be used more effectively, for example, for road monitoring by visual observation by the operator.

  (5) Preferably, each vehicle that passes through the first measurement area is photographed from the front side of each vehicle, and each vehicle that passes through the second measurement area is each vehicle. And a second photographing unit for photographing from the rear side.

  According to such a configuration, the direction from the first photographing unit to the vehicle photographed by the first photographing unit and the direction from the second photographing unit to the vehicle photographed by the second photographing unit are roads In the component parallel to the traveling direction, the directions are opposite. For this reason, for example, even when the amount of sunlight reflected in the first image specified by the first image data is large, the amount of sunlight reflected is small in the second image specified by the second image data. A second image can be obtained. Similarly, for example, even if the amount of sunlight reflected in the second image specified by the second image data is large, the amount of sunlight reflected is small in the first image specified by the first image data. A first image can be obtained. That is, during the time when the morning sun rises, the vehicle sensing process can be performed based on the image data of the first image and the second image with the smaller amount of reflected sunrise. Further, in the time zone when the sunset is set, the vehicle sensing process can be performed based on the image data of the first image and the second image with the smaller amount of sunset reflected. As a result, the vehicle sensing process can be performed on the basis of the image data of the image in which the direct sunlight is suppressed from being excessively reflected in both the time when the sun rises and the time when the sunset falls. . Therefore, it is possible to suppress a decrease in vehicle sensing performance caused by strong light such as sunlight. Further, for example, even when one of the first photographing unit and the second photographing unit cannot perform photographing for vehicle sensing due to maintenance or failure, the other photographing can be performed for vehicle sensing. it can. Thereby, the interruption of the process for detecting a vehicle can be suppressed more reliably.

  (6) Preferably, the said 1st imaging | photography part and the said 2nd imaging | photography part are arrange | positioned in the mutually opposite direction regarding the said advancing direction.

  Accordingly, the first photographing unit can photograph the vehicle head (front end) of the vehicle more reliably. In addition, the second photographing unit can more reliably photograph the stern (rear end) of the vehicle.

  (7) Preferably, an optical member is further provided, and the optical member optically guides the first image obtained by viewing the first measurement area from the front side of the first measurement area to the first photographing unit. And a second guide for optically guiding the second image obtained by viewing the second measurement area from the rear side of the second measurement area to the second imaging unit.

  Accordingly, the first image and the second image are guided to the corresponding first photographing unit and second photographing unit by the optical member, respectively. Therefore, the first photographing unit and the second photographing unit can indirectly photograph the first measurement area and the second measurement area via the optical member, respectively. Therefore, the first photographing unit and the second photographing unit do not need to be directly incident with sunlight, for example. Thereby, it can suppress that unnecessary light injects into a 1st imaging | photography part and a 2nd imaging | photography part. Accordingly, it is possible to further suppress a decrease in vehicle detection accuracy caused by strong light such as sunlight.

  (8) Preferably, an optical member and a single photographing unit that photographs an image from the optical member are further provided. The optical member includes a first guide unit for optically guiding a first image of the first measurement area viewed from the front side of the first measurement area to the one photographing unit; A second guide unit for optically guiding the second image obtained by viewing the measurement area from the rear side of the second measurement area to the one photographing unit. The first image data is based on the first image, and the second image data is based on the second image.

  According to such a configuration, the direction from the imaging unit toward the first measurement area and the direction from the imaging unit toward the second measurement area are opposite in the component parallel to the traveling direction of the road. For this reason, for example, even when the amount of sunlight reflected in the first image specified by the first image data is large, the amount of sunlight reflected is small in the second image specified by the second image data. A second image can be obtained. Similarly, for example, even if the amount of sunlight reflected in the second image specified by the second image data is large, the amount of sunlight reflected is small in the first image specified by the first image data. A first image can be obtained. That is, during the time when the morning sun rises, the vehicle sensing process can be performed based on the image data of the first image and the second image with the smaller amount of reflected sunrise. Further, in the time zone when the sunset is set, the vehicle sensing process can be performed based on the image data of the first image and the second image with the smaller amount of sunset reflected. As a result, the vehicle sensing process can be performed on the basis of the image data of the image in which the direct sunlight is suppressed from being excessively reflected in both the time when the sun rises and the time when the sunset falls. . Therefore, it is possible to suppress a decrease in vehicle sensing performance caused by strong light such as sunlight. The first image and the second image are each guided to the photographing unit by the optical member. Thereby, the imaging | photography part can image | photograph a 1st measurement area and a 2nd measurement area indirectly via an optical member. Therefore, for example, the photographing unit does not need to be directly incident with sunlight. Thereby, it can suppress that unnecessary light injects into an imaging | photography part. Accordingly, it is possible to further suppress a decrease in vehicle detection accuracy caused by strong light such as sunlight. Furthermore, the first measurement area and the second measurement area can be photographed by one photographing unit. Thereby, it is not necessary to provide two photographing units, and the manufacturing cost of the image type vehicle sensor can be further reduced. In addition, when either one of the photographing part where the first image is photographed or the second image is photographed is cleaned, vehicle detection is performed using image data obtained from the other part. Processing can continue. Therefore, even when there is one photographing unit, it is possible to suppress interruption of processing for sensing the vehicle.

  (9) Preferably, the selection unit outputs a sensing process result of the first processing unit in a predetermined first period, and the second unit in a predetermined second period different from the first period. The detection processing result of the processing unit is output.

  Thereby, the sensing result obtained using the image data more suitable for the sensing process of the vehicle among the first image data and the second image data can be output from the image type vehicle sensor.

  (10) More preferably, in the first period, the sunrise or the sun in the second image specified by the second image data is stronger than the intensity of the sunrise or the sunset in the first image specified by the first image data. Including a first shooting period in which the intensity of sunset is large, and the second period is specified by the first image data rather than the intensity of sunset or sunrise in the second image specified by the second image data. The second shooting period in which the intensity of sunset or morning sun in one image is large is included.

  As a result, during the first shooting period, vehicle detection is performed using the first image data obtained by shooting the first image with the smaller amount of reflection of the morning sun or the sunset from the first image and the second image. Processing can be performed. Accordingly, the vehicle sensing process can be performed with higher accuracy in a state where the influence of the morning sun or sunset is suppressed. Further, in the second shooting period, the vehicle sensing process is performed using the second image data obtained by shooting the second image with a smaller amount of sunset or sunrise in the first image and the second image. It can be performed. Accordingly, the vehicle sensing process can be performed with higher accuracy in a state where the influence of the sunset or the morning sun is suppressed.

  Preferably, the selection unit sets a period including a predetermined afternoon time zone as the second imaging period.

  As described above, the vehicle sensing process can be performed in a state in which the influence of the sunset is suppressed with a simple configuration in which the predetermined time zone in the afternoon is set as the second period. That is, a time-consuming process of measuring the intensity of sunset in the first image and the second image is not necessary.

  Preferably, the selection unit sets a period including a predetermined morning time zone as the first imaging period.

  Thus, the vehicle sensing process can be performed with a simple configuration in which a predetermined time zone in the morning is set as the first period, with the influence of Asahi being suppressed. That is, the time-consuming process of measuring the intensity of the morning sun in the first image and the second image is not necessary.

  (11) Preferably, the first period includes a first maintenance period for maintaining the second imaging unit that images the second measurement area, and the second period images the first measurement area. A second maintenance period for maintaining the first imaging unit is included.

  Note that “maintenance” includes at least one of cleaning the imaging unit, adjusting the orientation or position of the imaging unit, and checking whether there is an abnormality in the imaging unit.

  Thereby, the period which maintains a 1st imaging | photography part and the period which maintains a 2nd imaging | photography part can be varied. Therefore, even while one of the first photographing unit and the second photographing unit is being maintained, the other vehicle can be photographed on the road. As a result, the interruption of the process for sensing the vehicle can be more reliably suppressed.

  (12) In order to solve the above-described problem, a vehicle detection program according to an aspect of the present invention images one or a plurality of vehicles passing through a first measurement area on a road along a predetermined traveling direction on a computer. A step of accepting the first image data obtained in this manner, and second image data obtained by photographing the second measurement area on the road to which each of the vehicles that have passed through the first measurement area is taken. A program for executing an acceptable step and a step of outputting a sensing process result obtained by sensing each vehicle based on one of the first image data and the second image data.

  According to such a configuration, even if it is in a state in which vehicle detection cannot be performed for one of the first image data and the second image data, the vehicle detection process is performed using the other image data. It can be performed. Thereby, the interruption of the process for detecting a vehicle can be suppressed. For example, the second image data can be obtained by using the photographing unit for obtaining the second image data even when the photographing operation for obtaining the first image data is performed. Similarly, for example, even when a cleaning operation is performed on an imaging unit for obtaining the second image data, the first image data can be obtained using the imaging unit for obtaining the first image data. Therefore, the interruption of the process for detecting the vehicle can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the image-type vehicle sensor and vehicle detection program which can suppress the interruption of the process for detecting a vehicle are realizable.

(A) is a typical top view which shows an example of the image type vehicle sensor in 1st Embodiment of this Embodiment, (b) looked the periphery of the image type vehicle sensor from the width direction of the road. It is a typical side view. It is a functional block diagram of a vehicle detection part. It is a flowchart for demonstrating the vehicle detection operation | movement in the image type vehicle sensor which concerns on 1st Embodiment of this invention. It is a functional block diagram of the vehicle detection part of the image type vehicle sensor which concerns on 2nd Embodiment of this invention. It is a flowchart for demonstrating the vehicle detection operation | movement in the image type vehicle sensor which concerns on 2nd Embodiment. (A) is a typical perspective view which shows an example of the image type vehicle sensor in 3rd Embodiment of this Embodiment, (b) saw the periphery of the image type vehicle sensor from the width direction of the road. It is a typical side view. It is typical sectional drawing which shows the whole structure of an imaging device, and has shown one part by the side. (A) And (b) is a typical partial cross section side view of the principal part for demonstrating a some optical member. (A) And (b) is a partial cross section side view of the principal part for demonstrating the cleaning operation | work of an optical member. It is sectional drawing which shows the imaging device of the image type vehicle sensor which concerns on 4th Embodiment of this invention, and has shown one part by the side. It is a functional block diagram of the vehicle detection part of the image type vehicle sensor which concerns on 4th Embodiment of this invention. (A) And (b) is a figure for demonstrating the image correction process in an image correction part. It is a flowchart for demonstrating the vehicle detection operation | movement in the image type vehicle sensor concerning 4th Embodiment. It is a functional block diagram of the vehicle detection part of the image type vehicle sensor which concerns on 5th Embodiment of this invention. It is a flowchart for demonstrating the vehicle detection operation | movement in the image type vehicle sensor concerning 5th Embodiment.

[First embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Configuration of image-type vehicle detector]
FIG. 1A is a schematic plan view showing an example of the image type vehicle sensor 1 in the first embodiment. In FIG. 1A, the image type vehicle detector 1 is installed on the road 100. FIG. 1B is a schematic side view of the periphery of the image type vehicle detector 1 as viewed from the width direction of the road 100.

  As shown in FIGS. 1A and 1B, the image type vehicle detector 1 is provided for detecting one or a plurality of vehicles 101 passing through a road 100. In the present embodiment, “sensing” refers to sensing at least one of the presence / absence of the vehicle 101, the speed of each vehicle 101, and the number (traffic volume) of each vehicle 101, for example. Each vehicle 101 is, for example, a small car or a large car.

  In the present embodiment, an example will be described in which the road 100 is an asphalt-paved road, a three-lane straight road extending in the east-west direction, and a one-way road. In this embodiment, road 100 is installed in a place exposed to sunlight. On the road 100, the vehicle 101 passes along a predetermined traveling direction D1. That is, the traveling direction D1 is a direction along the east-west direction, and in this embodiment, is the east direction.

  The image type vehicle detector 1 is installed on the road 100. The image-type vehicle detector 1 is located between the first measurement area 2 and the second measurement area 3 in the traveling direction D1. The first measurement area 2 is an area provided on the road 100, and the vehicle 101 passes through the first measurement area 2. For example, the first measurement area 2 is provided over substantially the entire region in the width direction W1 of the road 100 and is provided over a length of several tens of meters in the traveling direction D1. The second measurement area 3 is provided at a predetermined distance, for example, several tens of meters from the first measurement area 2 toward the traveling direction D1.

  The second measurement area 3 is an area provided on the road 100, and the vehicle 101 that has passed through the first measurement area 2 passes through. That is, the first measurement area 2 and the second measurement area 3 are arranged side by side along the traveling direction D1. For example, the length of the second measurement area 3 is set to be approximately the same as the length of the first measurement area 2 in each of the width direction W1 and the traveling direction D1. In the present embodiment, the second measurement area 3 is arranged so as to be directly visible from the first measurement area 2.

  In the present embodiment, neither the exit nor the entrance of the vehicle 101 with respect to the road 100 is arranged between the first measurement area 2 and the second measurement area 3. Therefore, all the vehicles 101 that have passed through the first measurement area 2 pass through the second measurement area 3 unless an abnormal situation such as an accident occurs.

  During the time when the morning sun rises, the sun S1 is located near the horizontal plane. The time zone in which the morning sun rises is, for example, around 7 am to 8 am in winter in Japan. When the second measurement area 3 is viewed from the imaging device 4 (to be described later) of the image type vehicle sensor 1 during this time zone, the second measurement area 3 is accurately visually recognized due to the morning sun (eastern sun) such as direct sunlight. It becomes difficult to do.

  On the other hand, the sun S2 is located near the horizontal plane during the second shooting period as a time zone when the sunset goes. The second shooting period is a predetermined time zone in the afternoon, and is, for example, around 4 pm to 5 pm in winter in Japan. When the first measurement area 2 is viewed from the photographing device 4 during this time period, it is difficult to accurately visually recognize the first measurement area 2 due to sunset (western sun) such as direct sunlight.

  Therefore, when the second measurement area 3 is photographed and the vehicle 101 is sensed during the second photographing period, it is possible to prevent detection omission and erroneous detection of each vehicle 101 due to direct sunlight. Further, in the first shooting period other than the second shooting period, the first measurement area 2 may be shot and the vehicle 101 may be sensed.

  The image-type vehicle detector 1 is configured to be able to perform a sensing process for the vehicle 101 passing through the first measurement area 2 and a sensing process for the vehicle 101 passing through the second measurement area 3 in parallel. . Further, the image-type vehicle detector 1 alternatively outputs a detection process result of the vehicle 101 passing through the first measurement area 2 and a detection process result of the vehicle 101 passing through the second measurement area 3. Is configured to be possible.

  The image type vehicle detector 1 includes a photographing device 4 and a vehicle sensing unit 5.

  The photographing device 4 is provided for photographing the first measurement area 2 and the second measurement area 3. The imaging device 4 is attached to a portal column 100a installed on the road 100. The portal column 100a has column portions extending upward from both the left and right shoulders 100b of the road 100, and beam portions extending in the width direction W1 between these column portions. For example, the beam portion is arranged at a height of several m to several tens m from the road surface of the road 100. The imaging device 4 is attached to the column part. In the present embodiment, the photographing device 4 is configured to directly photograph the road 100.

  The imaging device 4 includes a first imaging unit 11 and a second imaging unit 12.

  The first photographing unit 11 is provided for photographing the first image 21. The first image 21 is an image of the first measurement area 2 viewed from the front side of the first measurement area 2 in the traveling direction D1. The first imaging unit 11 captures the first image 21 to capture one or more vehicles 101 that pass along the traveling direction D <b> 1 on the road 100 from the front side of each vehicle 101. An area photographed by the first photographing unit 11 in the road 100 is a first measurement area 2.

  The first imaging unit 11 generates first image data by capturing an incident image. The first imaging unit 11 is, for example, a CCD (Charge Coupled Device) camera or a CMOS (Complementary Metal Oxide Semiconductor) camera. The first imaging unit 11 is disposed, for example, at the center of the portal column 100a in the width direction W1.

  The first imaging unit 11 includes a case 13 supported by the beam portion of the portal column 100 a and an incident unit 14 supported by the case 13.

  The case 13 is formed in a box shape elongated in one direction. The case 13 is fixed to the portal column 100a using a bracket or the like (not shown) in a state where the case 13 is disposed so as to proceed downward as it proceeds in the direction opposite to the traveling direction D1. A cable (not shown) for outputting image data or the like extends from the front end of the case 13 in the traveling direction D1. This cable is connected to the vehicle sensing unit 5 through the portal column 100a. An incident portion 14 is disposed at the rear end portion of the case 13 in the traveling direction D1.

  The incident part 14 is provided as a part into which light is incident, and is configured by, for example, a lens. Incident portion 14 extends downward as it proceeds in the direction opposite to traveling direction D <b> 1, i.e., it faces diagonally downward and faces the road surface of road 100. The image incident on the incident unit 14 is incident on the image sensor included in the first imaging unit 11. The first photographing unit 11 outputs the image data generated by the image sensor or the like to the vehicle sensing unit 5 as first image data. A second imaging unit 12 is arranged so as to be adjacent to the first imaging unit 11.

  The second photographing unit 12 is provided for photographing the second image 22. The second image 22 is an image of the second measurement area 3 viewed from the rear side of the second measurement area 3 in the traveling direction D1. The second imaging unit 12 captures the second image 22 to capture one or more vehicles 101 that pass along the road 100 along the traveling direction D1 from the rear side of each vehicle 101. An area photographed by the second photographing unit 12 in the road 100 is the second measurement area 3.

  The second imaging unit 12 generates second image data by capturing an incident image. The second imaging unit 12 is, for example, a CCD camera or a CMOS camera, like the first imaging unit 11. The 2nd imaging | photography part 12 is arrange | positioned at the center part of the portal column 100a in the width direction W1, for example.

  The positions of the second photographing unit 12 and the first photographing unit 11 in the traveling direction D1 are substantially aligned. Moreover, the 2nd imaging | photography part 12 and the 1st imaging | photography part 11 are arrange | positioned in the mutually opposite direction regarding the advancing direction D1.

  The second imaging unit 12 includes a case 15 supported by the beam part of the portal column 100a and an incident part 16 supported by the case 15.

  The case 15 is formed in a box shape that is elongated in one direction. The case 15 is fixed to the portal column 100a using a bracket or the like (not shown) in a state where the case 15 is disposed so as to proceed downward as it proceeds in the traveling direction D1. A cable (not shown) for outputting image data or the like extends from the rear end of the case 15 in the traveling direction D1. This cable is connected to the vehicle sensing unit 5 through the portal column 100a. An incident portion 16 is disposed at the front end portion of the case 13 in the traveling direction D1.

  The incident portion 16 is provided as a portion where light is incident, and is configured by, for example, a lens. The incident portion 16 extends downward as it proceeds in the traveling direction D <b> 1, that is, faces obliquely downward and faces the road surface of the road 100. The image incident on the incident unit 16 is incident on the image sensor included in the second imaging unit 12. The second photographing unit 12 outputs the image data generated by the image sensor or the like to the vehicle sensing unit 5 as second image data.

  Next, the configuration of the vehicle sensing unit 5 will be described. FIG. 2 is a functional block diagram of the vehicle sensing unit 5. As shown in FIG. 1A and FIG. 2, the vehicle sensing unit 5 is disposed on the side of the road 100 and adjacent to the portal column 100 a and is electrically connected to the imaging device 4. . Further, the vehicle sensing unit 5 is electrically connected to the central processing unit 102 via a communication line or the like. The vehicle detection unit 5 outputs the vehicle detection result and the image data from each of the imaging units 11 and 12 to the central processing unit 102. The central processing unit 102 is, for example, a traffic control center.

  The vehicle sensing unit 5 performs the sensing process of the vehicle 101 based on the first image data generated by the imaging of the first imaging unit 11 and the second image data generated by the imaging of the second imaging unit 12. Do. In the present embodiment, the vehicle sensing unit 5 is configured to sense the presence / absence of the vehicle 101, the speed of each vehicle 101, and the number of each vehicle 101 for each of the measurement areas 2 and 3. The vehicle sensing unit 5 has a configuration as a computer including a CPU, a RAM, a ROM, and the like.

  The vehicle detection unit 5 includes a first image input unit 31, a first image detection processing unit 32, a second image input unit 33, a second image detection processing unit 34, a selection unit 35, and a detection data transmission unit 36. A timing unit 37, a maintenance information input unit 38, and an image data transmission unit 39. The first image detection processing unit 32 is configured using a CPU, and the second image detection processing unit 34 is configured using a CPU different from the first image detection processing unit 32. As described above, the first image detection processing unit 32 and the second image detection processing unit 34 are configured using two CPUs.

  The first image data generated by the first imaging unit 11 is input to the first image input unit 31. The first image input unit 31 outputs the first image data to the image data transmission unit 39.

  The first image input unit 31 outputs the first image data to the first image detection processing unit 32. The first image sensing processing unit 32 is provided as a first processing unit, and performs sensing processing of each vehicle 101 passing through the first measurement area 2 based on the first image data.

  The first image detection processing unit 32 includes a vehicle head point detection unit 41 and a first measurement unit 42.

  The vehicle head point detector 41 detects the vehicle head (front end) point of each vehicle 101 based on the first image data obtained by photographing the first image 21. Specifically, for example, the first image data includes each luminance P1 (i1, j1) of the image signal at each point of M1 × N1 coordinates (i1, j1). The coordinates (i1, j1) are coordinates determined from M1 sample points along the width direction W1 of the road 100 and N1 sample points along the traveling direction D1 of the road 100.

  Then, the vehicle head point detection unit 41 obtains a differential P1 ′ (i1, j1) of each luminance P1 (i1, j1) by performing a spatial differential process on the first image data. Further, the vehicle head point detection unit 41 binarizes all pixels subjected to the spatial differentiation process. That is, if the derivative P1 ′ (i1, j1) is greater than or equal to a predetermined threshold, P1 ′ (i1, j1) = 1 is set, and the derivative P1 ′ (i1, j1) is less than the predetermined threshold. If there is, P1 ′ (i1, j1) = 0 is set. Further, the vehicle head point detection unit 41 detects the vehicle head point of the vehicle 101 based on the distribution of the differential P1 ′ (i1, j1) and the like. The vehicle head point detection unit 41 outputs vehicle head point data specifying the detected vehicle head point to the first measurement unit 42.

  The first measurement unit 42 senses that the vehicle 101 is present in the first measurement area 2 when the vehicle head point detection unit 41 detects the vehicle head point of the vehicle 101. In this case, the first measurement unit 42 senses the speed of the vehicle 101 in the first measurement area 2 by measuring the position change of the head point of the vehicle 101 that senses the presence. Further, the first measurement unit 42 senses the number of vehicles 101 (traffic volume). The first measurement unit 42 outputs first sensing data indicating these sensing results to the selection unit 35.

  The second image data generated by the second imaging unit 12 is input to the second image input unit 33. The second image input unit 33 outputs the second image data to the image data transmission unit 39.

  Further, the second image input unit 33 outputs the second image data to the second image detection processing unit 34. The second image sensing processing unit 34 is provided as a second processing unit, and performs sensing processing for each vehicle 101 passing through the second measurement area 3 based on the second image data.

  In the present embodiment, two image detection processing units, a first image detection processing unit 32 and a second image detection processing unit 34, are provided. Thereby, the sensing process of the vehicle 101 by the first image sensing processor 32 and the sensing process of the vehicle 101 by the second image sensing processor 34 are performed in parallel.

  The second image detection processing unit 34 includes a vehicle tail point detection unit 43 and a second measurement unit 44.

  The vehicle tail point detector 43 detects the vehicle tail point in the same manner as the vehicle head point detector 41. Specifically, the vehicle tail point detector 43 detects the vehicle rear (rear end) point of each vehicle 101 based on the second image data obtained by photographing the second image 22. For example, the image data of the second measurement area 3 includes each luminance P2 (i2, j2) of the image signal at each point of M2 × N2 coordinates (i2, j2). The coordinates (i2, j2) are coordinates determined from M2 sample points along the width direction W1 of the road 100 and N2 sample points along the traveling direction D1 of the road 100.

  Then, the vehicle tail point detection unit 43 performs a spatial differentiation process on the second image data to obtain a differential P2 ′ (i2, j2) of each luminance P2 (i2, j2). Further, the vehicle tail point detection unit 43 binarizes all the pixels subjected to the spatial differentiation process. That is, if the derivative P2 ′ (i2, j2) is equal to or greater than a predetermined threshold, P2 ′ (i2, j2) = 1 is set, and the derivative P2 ′ (i2, j2) is less than the predetermined threshold. If there is, P2 ′ (i2, j2) = 0 is set. Further, the vehicle tail point detection unit 43 detects the vehicle tail point of the vehicle 101 based on the distribution of the derivative P2 ′ (i2, j2) and the like. The vehicle rear point detection unit 43 outputs vehicle rear point data for specifying the detected vehicle rear point to the second measurement unit 44.

  The second measurement unit 44 senses that the vehicle 101 is present in the second measurement area 3 when the vehicle tail point of the vehicle 101 is detected by the vehicle tail point detection unit 43. In this case, the second measurement unit 44 senses the speed of the vehicle 101 in the second measurement area 3 by measuring a change in the position of the tail point of the vehicle 101 that has sensed the presence. Furthermore, the second measuring unit 44 senses the number of vehicles 101 (traffic volume). The second measuring unit 44 outputs second sensing data indicating these sensing results to the selecting unit 35.

  The selection unit 35 is configured to be able to select which of the detection processing result in the first image detection processing unit 32 and the detection processing result in the second image detection processing unit 34 is output. That is, the selection unit 35 is configured to be able to select which of the first sensing data and the second sensing data is output.

  The selection unit 35 selects which of the first sensing data and the second sensing data is output based on the time information of the time measuring unit 37 or the maintenance information input to the maintenance information input unit 38.

  The timer 37 is, for example, a clock, and has time information at the place where the image type vehicle detector 1 is installed. The timer 37 is connected to the selector 35. The selector 35 determines the time by reading the time information of the timer 37.

  When the current time is a time within the first imaging period, the selection unit 35 outputs the first sensing data to the sensing data transmission unit 36. The first photographing period is a period in which the intensity of the morning sun in the second image specified by the second image data is greater than the intensity (illuminance) of the morning sun in the first image specified by the first image data. Including. The selection unit 35 sets a time zone including a predetermined morning time zone as the first imaging period. The predetermined time zone in the morning is the time zone in which the morning sun rises as described above.

  On the other hand, when the current time is a time within the second shooting period, the selection unit 35 outputs the second sensing data to the sensing data transmission unit 36. The second shooting period includes a period in which the sunset intensity in the first image specified by the first image data is larger than the sunset intensity in the second image specified by the second image data. The selection unit 35 sets a predetermined afternoon time zone as the second imaging period. The predetermined time zone in the morning is the time zone in which the sunset is set as described above. A period other than the second shooting period is set as the first shooting period.

  A maintenance information input unit 38 is connected to the selection unit 35. The maintenance information input unit 38 is connected to the central processing unit 102, for example. Maintenance information related to the imaging device 4 is output from the central processing unit 102 to the maintenance information input unit 38. In the present embodiment, “maintenance” refers to cleaning, adjusting the orientation or position of each of the first imaging unit 11 and the second imaging unit 12, and confirming whether there is an abnormality. Of at least one.

  Maintenance information is output from the central processing unit 102 to the maintenance information input unit 38. This maintenance information is output, for example, when the operator operates an output device (not shown). The maintenance information includes information indicating that maintenance is performed on the first imaging unit 11 or the second imaging unit 12. For example, the maintenance information is output when an operator or the like confirms that the images photographed by the photographing units 11 and 12 are abnormal or have a certain level of dirt.

  That is, when an operator or the like decides to maintain the first imaging unit 11, information indicating that the first imaging unit 11 is maintained is output from the central processing unit 102 to the maintenance information input unit 38. This information includes information indicating when the second maintenance period as a period for maintaining the first imaging unit 11 is. Further, when an operator or the like determines that the second imaging unit 12 needs to be maintained, information indicating that the second imaging unit 12 is maintained is output from the central processing unit 102 to the maintenance information input unit 38. This information includes information on when the first maintenance period as a period for maintaining the second imaging unit 12 is.

  The maintenance information may be periodically output to the maintenance information input unit 38 by an apparatus provided in the central processing unit 102 or the like.

  The maintenance information output to the maintenance information input unit 38 is output from the maintenance information input unit 38 to the selection unit 35. The selection unit 35 reads the given maintenance information. The selection unit 35 outputs the first sensing data to the sensing data transmission unit 36 during a period corresponding to the first maintenance period. On the other hand, the selection unit 35 outputs the second sensing data to the sensing data transmission unit 36 during the period corresponding to the second maintenance period.

  Hereinafter, the first imaging period and the first maintenance period are collectively referred to as “first period”. In addition, the second imaging period and the second maintenance period are collectively referred to as “second period”.

  As described above, the first sensing data or the second sensing data output to the sensing data transmission unit 36 is output from the sensing data transmission unit 36 to the central processing unit 102. The central processing unit 102 is connected to the sensing data transmission unit 36 and is also connected to the image data transmission unit 39.

  As described above, the image data transmission unit 39 is connected to the first image input unit 31 and the second image input unit 33. The image data transmission unit 39 is provided as an image data output unit that outputs at least one of the first image data and the second image data to the central processing unit 102. For example, the image data transmission unit 39 outputs at least one of the first image data and the second image data to the central processing unit 102 based on a command signal from the central processing unit 102.

  The central processing unit 102 is provided with a monitor (not shown) that can be viewed by an operator. The image data output to the central processing unit 102 is output to the monitor. As a result, at least one of the first image 21 and the second image 22 is displayed on the monitor.

[Vehicle sensing operation in image type vehicle detector]
FIG. 3 is a flowchart for explaining a vehicle sensing operation in the image type vehicle sensor 1 according to the first embodiment of the present invention. The image type vehicle sensor 1 reads out each step of each flowchart shown below from a memory (not shown) and executes it. This program can be installed externally. The installed program is distributed in a state stored in a recording medium, for example.

  The vehicle sensing operation will be described with reference to FIGS. 1 and 2 as appropriate in addition to FIG. The first image data generated by the imaging operation of the first imaging unit 11 is output to the first image input unit 31, and further output from the first image input unit 31 to the vehicle head point detection unit 41 (step S11). . In parallel with this processing, the second image data generated by the photographing operation of the second photographing unit 12 is output to the second image input unit 33, and further from the second image input unit 33 to the vehicle tail point detection unit 43. (Step S11).

  The vehicle head point detection unit 41 reads the first image data and performs the above-described spatial differentiation process to detect the vehicle head point of each vehicle 101 (step S12). In parallel with this process, the vehicle head point detection unit 43 detects the tail point of each vehicle 101 by reading the second image data and performing the above-described spatial differentiation process or the like (step S12).

  Next, the first measurement unit 42 performs a sensing process for sensing the presence / absence of each vehicle 101, the speed of each vehicle 101, and the number of vehicles 101 based on the detected change in the vehicle head point, etc. 1 sense data is generated (step S13). In parallel with this processing, the second measuring unit 44 senses the presence / absence of each vehicle 101, the speed of each vehicle 101, and the number of vehicles 101 based on the detected change in the tail point of the vehicle. Processing is performed to generate second sensing data (step S13).

  Next, the selection unit 35 determines whether the current time is the first period or the second period (step S14).

  When the current time is the first period, that is, when it is the first imaging period or the first maintenance period (the first period in step S14), the selection unit 35 generates the first generated by the first measurement unit 42. The sensing data is output to the sensing data transmission unit 36. The sense data transmission unit 36 outputs the first sense data to the central processing unit 102 (step S15).

  On the other hand, when the current time is the second period, that is, when it is the second imaging period or the second maintenance period (the second period in step S14), the selection unit 35 is generated by the second measurement unit 44. The second sensing data is output to the sensing data transmission unit 36. The sensing data transmission unit 36 outputs the second sensing data to the central processing unit 102 (step S16).

  In step S14, a case where the first imaging period and the second maintenance period overlap, or a case where the second imaging period and the first maintenance period overlap may be considered. In this case, for example, the maintenance period is prioritized, that is, whether the first period or the second period is determined based on the maintenance period.

[Installation work of image type vehicle detector]
As shown in FIG. 1A and FIG. 1B, when the image type vehicle detector 1 is installed on the road 100, first, the photographing device 4 is installed on the portal column 100a. Further, the vehicle sensing unit 5 is installed on the road shoulder 100b. Next, the ranges of the measurement areas 2 and 3 such as the direction with respect to the road 100 are adjusted for each of the imaging units 11 and 12. During this adjustment, the section between the lanes of the road 100 and the shooting magnification of each lane are also adjusted.

  Next, each imaging unit 11, 12 is activated, and images taken by each imaging unit 11, 12 are confirmed. Thereafter, the plurality of vehicles 101 are run on a trial basis. Then, evaluation of the average speed, the number of vehicles traveling, and the vehicle type obtained by sensing these vehicles 101 is performed, and various parameters are adjusted as necessary. Thereby, the installation work of the image type vehicle detector 1 is completed.

  As described above, in the image type vehicle sensor according to the embodiment of the present invention, the selection unit 35 includes the detection processing result in the first image detection processing unit 32 and the detection processing result in the second image detection processing unit 34. Which of these can be output can be selected. That is, the selection unit 35 can select which of the sensing process result using the first image data and the sensing process result using the second image data is to be output. As a result, even if one of the first image data and the second image data is in a state where vehicle detection cannot be performed, vehicle detection processing can be performed using the other image data. . Thereby, the interruption of the process for detecting a vehicle can be suppressed. For example, even when the first photographing unit 11 is cleaned, the second image data can be obtained using the second photographing unit 12. Similarly, for example, even when the second photographing unit 12 is cleaned, the first image data can be obtained using the first photographing unit 11. Therefore, it is possible to realize an image type vehicle detector that can suppress interruption of processing for detecting the vehicle 101.

  Further, regarding the reason why the interruption of the process for sensing the vehicle 101 can be suppressed, the first image data and the second image data are selected from the one photographing unit by changing the direction of one photographing unit. This will be explained in comparison with the case of receiving it as a single unit. In order to selectively receive the first image data and the second image data from one photographing unit, in order to switch between a state in which the first image data is output from one photographing unit and a state in which the second image data is output. Requires time to change the orientation of the one photographing unit. Therefore, the vehicle 101 cannot be photographed in such a manner that the vehicle 101 can be sensed while the direction of the one photographing unit is changed. For this reason, the photographing process for sensing the vehicle 101 is interrupted. In addition, the photographing process for sensing the vehicle 101 is interrupted while a maintenance operation such as cleaning the lens is performed for one photographing unit. Furthermore, when a failure occurs in the drive mechanism for changing the orientation of one photographing unit, the photographing process for sensing the vehicle 101 is interrupted during the repair of the drive mechanism.

  On the other hand, in the image type vehicle sensor according to the embodiment of the present invention, it is possible to receive the first image data and the second image data from the first photographing unit 11 and the second photographing unit 12, respectively. . Therefore, when switching between the state in which the first image data is output from the first image capturing unit 11 and the state in which the second image data is output from the second image capturing unit 12, it is necessary to displace any of the image capturing units 11 and 12. There is no. Therefore, a blank time does not occur while switching between the state in which the vehicle detection process is performed using the first image data and the state in which the vehicle detection process is performed using the second image data. Thereby, the interruption of the imaging process for sensing the vehicle 101 can be suppressed. In addition, for example, while one of the first photographing unit 11 and the second photographing unit 12 is performing a maintenance operation such as cleaning a lens, the photographing operation of the vehicle 101 can be continued on the other. . Therefore, it is possible to suppress interruption of the photographing process for sensing the vehicle 101 even while the maintenance work is being performed. Furthermore, since a drive mechanism that changes the orientation of the photographing units 11 and 12 is not necessary, interruption of the photographing process due to a failure of the drive mechanism can be suppressed.

  Further, in the image type vehicle detector according to the embodiment of the present invention, the first image detection processing unit 32 and the second image detection processing unit 34 can perform the detection processing of each vehicle in parallel. The selection unit 35 can output either the detection processing result in the first image detection processing unit 32 or the detection processing result in the second image detection processing unit 34. As a result, it is possible to more quickly switch from the state in which the detection processing result by one of the first image detection processing unit 32 and the second image detection processing unit 34 is output to the state in which the detection processing result by the other is output. Can be done. As a result, the loss of the sensing processing result of the vehicle 101 can be reduced.

  In the image type vehicle sensor according to the embodiment of the present invention, an image data transmission unit 39 that outputs at least one of the first image data and the second image data is provided. Thereby, at least one of the first image data and the second image data can be output to the central processing unit 102. Thereby, the image of the road 100 can be copied on the monitor of the central processing unit 102. As a result, at least one of the first image data and the second image data obtained by photographing for vehicle sensing can also be used for road monitoring by an operator's visual observation. Thereby, for example, when an accident occurs on the road 100, the road condition can be confirmed for at least one of the first measurement area 2 and the second measurement area 3. Thereby, the first image data and the second image data can be used more effectively, for example, for road monitoring by visual observation by the operator.

  In the image type vehicle sensor according to the embodiment of the present invention, the first photographing unit 11 for photographing each vehicle 101 passing through the first measurement area 2 from the front side of each vehicle 101, and the second measurement. A second imaging unit 12 for imaging each vehicle 101 passing through the area 3 from the rear side of each vehicle 101 is provided. Thus, the direction from the first photographing unit 11 toward the vehicle 101 photographed by the first photographing unit 11 and the direction from the second photographing unit 12 toward the vehicle 101 photographed by the second photographing unit 12 are: The component parallel to the traveling direction D1 of the road 100 is in the opposite direction. Therefore, even if the amount of sunlight reflected in the first image specified by the first image data is large, the amount of sunlight reflected is small in the second image specified by the second image data. Two images can be obtained. Similarly, even if the amount of sunlight reflected in the second image specified by the second image data is large, the amount of sunlight reflected is small in the first image specified by the first image data. One image can be obtained. That is, during the time when the morning sun rises, the sensing process of the vehicle 101 can be performed based on the first image data of the first image of the first image and the second image with a small amount of reflected sunrise. . In addition, during the sunset time, the vehicle 101 can be detected based on the second image data of the second image with the least amount of sunset reflected out of the first image and the second image. . As a result, the vehicle 101 can be detected based on the image data of an image in which direct sunlight is suppressed from being excessively reflected in both the time when the sun rises and the time when the sunset falls. it can. Therefore, it is possible to suppress a decrease in vehicle sensing performance caused by strong light such as sunlight. Furthermore, for example, even when one of the first photographing unit 11 and the second photographing unit 12 cannot perform photographing for vehicle detection due to maintenance or failure, the other photographing is performed for vehicle detection. be able to. Thereby, the interruption of the process for detecting a vehicle can be suppressed more reliably.

  Further, in the image type vehicle sensor according to the embodiment of the present invention, the first photographing unit 11 and the second photographing unit 12 are arranged in opposite directions with respect to the traveling direction D1. Accordingly, the first photographing unit 11 can more reliably photograph the vehicle head (front end) of the vehicle 101. In addition, the second photographing unit 12 can photograph the tail (rear end) of the vehicle 101 more reliably.

  In the image type vehicle sensor according to the embodiment of the present invention, the selection unit 35 outputs the detection processing result of the first image detection processing unit 32 in the first period, and is different from the first period. In the period, the detection processing result of the second image detection processing unit 34 is output. As a result, a sensing result obtained using image data more suitable for sensing processing of the vehicle 101 out of the first image data and the second image data can be output from the image type vehicle sensor.

  More specifically, in the image type vehicle sensor according to the embodiment of the present invention, the first period is specified by the second image data rather than the strength of the morning sun in the first image specified by the first image data. Including a first shooting period in which the intensity of the morning sun in the second image is large, and the second period is specified by the first image data rather than the intensity of the sunset in the second image specified by the second image data. A second shooting period in which the intensity of sunset in the first image is large is included. Thereby, in the first shooting period, the vehicle 101 is used by using the first image data obtained by shooting the first image 21 of the first image 21 and the second image 22 having a smaller amount of reflected sunrise. Can be detected. As a result, the sensing process of the vehicle 101 can be performed with higher accuracy while the influence of Asahi is suppressed. Further, in the second shooting period, the second image data obtained by shooting the second image 22 of the first image 21 and the second image 22 with a smaller amount of reflected sunset is used. Sensing processing can be performed. Thereby, the sensing process of the vehicle 101 can be performed with higher accuracy while the influence of the sunset is suppressed.

  In the image type vehicle sensor according to the embodiment of the present invention, the selection unit 35 sets a period including a predetermined afternoon time period as the second imaging period. In this way, the sensing process of the vehicle 101 can be performed with a simple configuration in which the predetermined time zone in the afternoon is set as the second period and the influence of the sunset is suppressed. That is, the time-consuming process of measuring the intensity of sunset in the first image 21 and the second image 22 is not necessary.

  Further, in the image type vehicle sensor according to the embodiment of the present invention, the selection unit 35 sets a period including a predetermined morning time period as the first imaging period. In this way, the sensing process of the vehicle 101 can be performed with a simple configuration in which a predetermined time zone in the morning is set as the first period, with the influence of Asahi being suppressed. That is, the time-consuming process of measuring the intensity of the morning sun in the first image 21 and the second image 22 is not necessary.

  In the image-type vehicle detector according to the embodiment of the present invention, the first period includes a first maintenance period for maintaining the second imaging unit 12 that images the second measurement area 3, and the second period. Includes a second maintenance period for maintaining the first imaging unit 11 that images the first measurement area 2. Thereby, the period which maintains the 1st imaging | photography part 11 and the period which maintains the 2nd imaging | photography part 12 can be varied. Therefore, even while one of the first photographing unit 11 and the second photographing unit 12 is being maintained, the other can photograph the vehicle 101 passing through the road 100. As a result, the interruption of the process for sensing the vehicle 101 can be more reliably suppressed.

[Second Embodiment]
FIG. 4 is a functional block diagram of the vehicle sensing unit 5B of the image type vehicle sensor according to the second embodiment of the present invention. As shown in FIG. 4, the main difference between the image type vehicle sensor according to the second embodiment of the present invention and the image type vehicle sensor according to the first embodiment is that one image detection processing unit 51. Thus, the sensing process of the vehicle 101 is performed.

  The vehicle sensing unit 5B includes a first image input unit 31, a second image input unit 33, a selection unit 52, an image sensing processing unit 51, a sensing data transmission unit 36, a timing unit 37, and a maintenance information input unit. 38 and an image data transmission unit 39. The image sensing processing unit 51 is configured using, for example, one CPU.

  The first image input unit 31 outputs the first image data output from the first imaging unit 11 to the selection unit 52 and the image data transmission unit 39.

  The second image input unit 33 outputs the second image data output from the second imaging unit 12 to the selection unit 52 and the image data transmission unit 39.

  The selection unit 52 is configured to be able to select which of the first image data and the second image data is output to the image detection processing unit 51. That is, the selection unit 52 can instruct the image detection processing unit 51 to perform the detection processing of the vehicle 101 based on which of the first image data and the second image data. . The selection unit 52 selects whether to output the first image data or the second image data based on the time information of the time measuring unit 37 or the maintenance information input to the maintenance information input unit 38.

  When the current time is a time within the first shooting period, the selection unit 52 outputs the first image data to the image sensing processing unit 51. On the other hand, when the current time is a time within the second shooting period, the selection unit 52 outputs the second image data to the image sensing processing unit 51.

  Further, the selection unit 52 outputs the first image data to the image sensing processing unit 51 during the period corresponding to the first maintenance period. On the other hand, the selection unit 52 outputs the second image data to the image sensing processing unit 51 during the period corresponding to the second maintenance period.

  The image sensing processing unit 51 functions as a first processing unit that performs sensing processing of the vehicle 101 based on the first image data, and as a second processing unit that performs sensing processing of the vehicle 101 based on the second image data. And has a function.

  The image sensing processing unit 51 includes a vehicle head point detection unit 41, a vehicle rear point detection unit 43, and a measurement unit 53.

  The selection unit 52 outputs the first image data to the vehicle head point detection unit 41 in the first period. In this case, the vehicle head point detection unit 41 outputs vehicle head point data specifying the detected vehicle head point to the measurement unit 53. On the other hand, the selection unit 52 outputs the second image data to the vehicle tail point detection unit 43 in the second period. In this case, the vehicle tail point detection unit 43 outputs vehicle tail point data for specifying the detected vehicle rear point to the measurement unit 53.

  When the vehicle head point detection unit 41 detects the vehicle head point of the vehicle 101, the measurement unit 53 senses that the vehicle 101 exists in the first measurement area 2. Further, the measurement unit 53 senses the speed of the vehicle 101 in the first measurement area 2 by measuring a change in the position of the head point of the vehicle 101 that has sensed the presence. Further, the measurement unit 53 senses the number of vehicles 101. In the measurement unit 53, first sensing data indicating these sensing processing results is generated.

  On the other hand, the measurement unit 53 senses that the vehicle 101 exists in the second measurement area 3 when the vehicle rear point detection unit 43 detects the vehicle rear point of the vehicle 101. In this case, the measurement unit 53 senses the speed of the vehicle 101 in the second measurement area 3 by measuring the position change of the tail point of the vehicle 101 that has sensed the presence. Further, the measurement unit 53 senses the number of vehicles 101. In the measurement unit 53, second sensing data indicating these sensing processing results is generated.

  The measurement unit 53 outputs the first sensing data or the second sensing data to the sensing data transmission unit 36. The sensing data transmission unit 36 outputs the first sensing data or the second sensing data to the central processing unit 102.

[Vehicle sensing operation in the image type vehicle sensor according to the second embodiment]
FIG. 5 is a flowchart for explaining a vehicle sensing operation in the image type vehicle sensor according to the second embodiment. A vehicle sensing operation in the image type vehicle sensor according to the second embodiment will be described with reference to FIGS. 4 and 5.

  The first image data generated by the imaging operation of the first imaging unit 11 is output to the first image input unit 31, and is further output from the first image input unit 31 to the selection unit 52 (step S21). In parallel with this processing, the second image data generated by the photographing operation of the second photographing unit 12 is output to the second image input unit 33, and further output from the second image input unit 33 to the selection unit 52. (Step S21).

  When the current time is the first period, that is, when it is the first imaging period or the first maintenance period (the first period in step S22), the selection unit 52 converts the first image data into the vehicle head point detection unit 41. (Step S23). In this case, the vehicle head point detection unit 41 detects the vehicle head point and outputs vehicle head point data to the measurement unit 53 (step S24). The measurement unit 53 performs a sensing process for each vehicle 101 based on the detected vehicle head point, and generates first sensing data (step S25).

  On the other hand, when the current time is the second period, that is, when it is the second imaging period or the second maintenance period (second period in step S22), the selection unit 52 performs the stern inspection on the second image data. It outputs to the output part 43 (step S26). In this case, the vehicle rear point detection unit 43 detects the vehicle rear point and outputs vehicle rear point data to the measurement unit 53 (step S27). The measurement unit 53 performs a sensing process for each vehicle 101 based on the detected vehicle tail point, and generates second sensing data (step S28).

  The first sensing data or the second sensing data generated by the measurement unit 53 is output from the sensing data transmission unit 36 to the central processing unit 102 (step S29).

  As described above, in the image type vehicle sensor according to the embodiment of the present invention, the selection unit 52 selects one of the first image data and the second image data for one image detection processing unit 51. It is possible to instruct whether to perform the sensing process of each vehicle 101 based on the above. Thereby, both the vehicle sensing process using 1st image data and the vehicle sensing process using 2nd image data can be performed with one image sensing process part 51. FIG. Therefore, the manufacturing cost of the image type vehicle sensor can be further reduced.

[Third embodiment]
FIG. 6A is a schematic perspective view illustrating an example of the image type vehicle detectors 1C and 1CC in the third embodiment. In Fig.6 (a), the image type vehicle detectors 1C and 1CC have shown the state installed in the road 100C. FIG. 6B is a schematic side view of the periphery of the image type vehicle detector 1C as viewed from the width direction of the road 100C.

  In the following, the image type vehicle sensor 1C out of the image type vehicle detectors 1C and 1CC will be mainly described. Regarding the image type vehicle sensor 1CC, the difference from the image type vehicle sensor 1C will be described, and the description of the same configuration will be omitted.

  As shown in FIGS. 6A and 6B, the image-type vehicle detector 1C is provided to detect one or a plurality of vehicles 101 passing through the road 100C. In the present embodiment, the road 100C is a one-lane road.

  The image type vehicle detector 1C is installed beside the road 100C. The image type vehicle detector 1C is located between the first measurement area 2C and the second measurement area 3C in the traveling direction D1. The first measurement area 2C and the second measurement area 3C are provided, for example, over substantially the entire region in the width direction W1 of the road 100C.

  During the time when the morning sun rises, the sun S1 is located near the horizontal plane. When the second measurement area 3C is viewed from the imaging device 4C, which will be described later, of the image type vehicle sensor 1C during this time period, the second measurement area 3C is accurately visually recognized due to the morning sun (eastern sun) such as direct sunlight. It becomes difficult to do.

  On the other hand, the sun S2 is located near the horizontal plane during the second shooting period as a time zone when the sunset goes. When the first measurement area 2C is viewed from the imaging device 4C during this time period, it is difficult to accurately view the first measurement area 2C due to sunset (western sun) such as direct sunlight.

  Therefore, when the second measurement area 3C is photographed and the vehicle 101 is sensed during the second photographing period, it is possible to prevent detection omission and erroneous detection of each vehicle 101 due to direct sunlight. Further, in the first shooting period other than the second shooting period, the sensing process of the vehicle 101 may be performed by shooting the first measurement area 2C.

  The image type vehicle detector 1 </ b> C includes a photographing device 4 </ b> C and a vehicle detection unit 5.

  The photographing device 4C is installed beside the road 100C. The imaging device 4C has, for example, a shape extending in the up-down direction Z1 as a direction perpendicular to the road surface of the road 100C. The imaging device 4C is disposed between the first measurement area 2C and the second measurement area 3C in the traveling direction D1.

  FIG. 7 is a schematic cross-sectional view showing the overall configuration of the photographing apparatus 4C, and shows a part on the side. As shown in FIG. 7, the imaging device 4C includes a base unit 106, a first shaft 107, an optical member 108, a second shaft 109, a support base 110, a first imaging unit 11C, and a second imaging unit. 12C and a housing 113.

  The base unit 106 is provided as a basic part of the photographing apparatus 4C. The base portion 106 is disposed on the shoulder 100b on the side of the road 100C. For example, the base portion 106 has a shape in which a lid is attached to each of an upper end and a lower end of a cylinder. The base portion 106 supports the lower portion of the first shaft 107 through a bearing 120 so as to be rotatable.

  The first shaft 107 is provided to rotatably support the optical member 108. The first shaft 107 extends straight along the vertical direction Z <b> 1 and extends upward from the base portion 106. Thereby, the 1st axis | shaft 107 is supported so that rotation to the periphery of the central axis L1 parallel to the up-down direction Z1 is possible. The central axis L1 is also the central axis of the first shaft 107. The diameter of the upper end portion of the first shaft 107 is made smaller than the diameter of the intermediate portion of the first shaft 107. An optical member 108 is detachably attached to the upper end portion.

  As shown in FIGS. 6B and 7, the optical member 108 is provided to optically guide the image of the road 100C to the photographing unit 11C. More specifically, the optical member 108 optically transmits the first image 21C as an image obtained by viewing the first measurement area 2C from the front side of the first measurement area 2C in the traveling direction D1 to the first imaging unit 11C. It is provided for guidance. Further, the optical member 108 optically guides the second image 22C as an image obtained by viewing the second measurement area 3C from the rear side of the second measurement area 3C in the traveling direction D1 to the second imaging unit 12C. Is provided.

  The optical member 108 is, for example, a reflecting member that reflects light. A mirror can be illustrated as such a reflecting member. Examples of the mirror include a mirror-finished metal, and a metal obtained by vapor-depositing a metal on one side of a transparent plate glass or plastic plate. Among these, as the optical member 108, it is preferable to use one obtained by vapor-depositing metal on one side of a transparent plate glass or plastic plate. With such a configuration, in the optical member 108, generation of rust caused by exhaust gas from the vehicle 101, rainwater, and the like can be suppressed.

  The optical member 108 has a frustum shape as a tapered shape in which the cross-sectional area perpendicular to the up-down direction Z1 becomes smaller as it goes downward. In the present embodiment, the optical member 108 is formed in a truncated cone shape whose diameter decreases as it proceeds downward. Thereby, in this Embodiment, the whole optical member 108 comprises the truncated cone shape part. The optical member 108 only needs to include a truncated cone-shaped portion at least partially, and may include other shapes. A shaft insertion hole is formed in the optical member 108. The shaft insertion hole is open to the lower end surface of the optical member 108, and the upper end portion of the first shaft 107 is fixed by press-fitting, for example. The optical member 108 can rotate around the first shaft 107 by, for example, manual work by an operator. The optical member 108 is rotated, for example, when the outer peripheral surface 108a of the optical member 108 is cleaned.

  The outer peripheral surface 108a of the optical member 108 is contaminated with foreign matter such as dust, fine particles contained in exhaust gas, and rainwater (hereinafter also simply referred to as foreign matter). In particular, half of the outer peripheral surface 108 a of the optical member 108 facing the road 100 </ b> C is easily contaminated by exhaust gas from the vehicle 101. However, the photographing device 4C is disposed on the road shoulder 100b spaced from the road 100C in the width direction W1, and the degree of contamination of the outer peripheral surface 108a due to the exhaust gas and dust rising from the road 100C can be relatively small.

  The optical member 108 only needs to be detachable from the first shaft 107, and the manner of fixing to the first shaft 107 is not limited to the above configuration. The optical member 108 is supported coaxially with the first shaft 107 by the first shaft 107.

  The outer peripheral surface 108a of the optical member 108 faces downward in the vertical direction Z1. When the outer peripheral surface 108a is viewed from the side, the generatrix L2 of the outer peripheral surface 108a has a predetermined inclination angle θ with respect to the central axis L1. The inclination angle θ of the optical member 108 is appropriately set according to the range of the first measurement area 2C and the range of the second measurement area 3C.

  The first image 21C and the second image 22C are configured to enter the outer peripheral surface 108a of the optical member 108. Specifically, a first guide part 121 and a second guide part 122 are formed on the outer peripheral surface 108 a of the optical member 108.

  The first guide 121 is provided to optically guide the first image 21C to the first photographing unit 11C. The first guide portion 121 is formed by a portion of the outer peripheral surface 108a of the optical member 108 that faces the first measurement area 2C side. In the present embodiment, the range in which the first guide portion 121 is formed in the circumferential direction of the optical member 108 is set to be less than a half circumference of the outer peripheral surface 108a. Further, in the height direction of the optical member 108, that is, in the vertical direction Z1, the range in which the first guide portion 121 is formed is set to a part of the height of the outer peripheral surface 108a. The first guide part 121 reflects the incident light, that is, the first image 21C downward. Thereby, the first image 21C is reflected toward the first imaging unit 11C located at a first position P1 described later. The 2nd guide part 122 is arrange | positioned in the position adjacent to the 1st guide part 121 in the circumferential direction of the outer peripheral surface 108a.

  The second guide unit 122 is provided to optically guide the second image 22C to the second imaging unit 12C. The second guide portion 122 is formed by a portion of the outer peripheral surface 108a of the optical member 108 that faces the second measurement area 3C side. In the present embodiment, the range in which the second guide portion 122 is formed in the circumferential direction of the optical member 108 is set to be less than a half circumference of the outer peripheral surface 108a. Further, in the height direction of the optical member 108, that is, the vertical direction Z1, the range in which the second guide portion 122 is formed is set to a part of the height of the outer peripheral surface 108a. The second guide part 122 reflects the incident second image 22C downward. Thereby, the second image 22C is reflected toward the second imaging unit 12C located at a second position P2 described later.

  The optical member 108 is disposed at the uppermost part of the photographing apparatus 4 </ b> C and has a function as an umbrella for each member positioned below the optical member 108. Specifically, the optical member 108 covers at least a part of the first imaging unit 11C and the second imaging unit 12C from above. In the present embodiment, the optical member 108 covers all of the first imaging unit 11C and the second imaging unit 12C from above.

  Further, the optical member 108 covers all parts of the photographing apparatus 4C other than the optical member 108 from above. Thus, the optical member 108 covers at least a part (all in the present embodiment) of the housing 113 from above. A second shaft 109 is disposed below the optical member 108 having the above configuration.

  The second shaft 109 is provided to support the first imaging unit 11C and the second imaging unit 12C. The second shaft 109 is formed in a hollow cylindrical shape that extends straight along the vertical direction Z1 and surrounds the first shaft 107. The second shaft 109 is fixed to the base portion 106. The second shaft 109 extends upward from the base portion 106. A support base 110 is fixed to the upper part of the second shaft 109. The second shaft 109 supports the first imaging unit 11C and the second imaging unit 12C via the support base 110.

  The support base 110 is an annular member formed by a plate member having a predetermined thickness. For example, the first photographing unit 11C and the second photographing unit 12C are fixed to the upper surface of the support base 110, for example.

  The first imaging unit 11C generates first image data by capturing an image incident from the optical member 108. 11C of 1st imaging | photography parts are arrange | positioned in the 1st position P1 on the support stand 110. FIG. At the first position P1, the first photographing unit 11C can photograph only the first measurement area 2C out of the first measurement area 2C and the second measurement area 3C. The first position P1 is, for example, a position below the first guide 121.

  The case 13C of the first imaging unit 11C is fixed to the support base 110. The case 13C is formed in an elongated shape in the vertical direction Z1, and the upper end portion of the case 13C is distanced from the support base 110. Thereby, it can suppress that the foreign material collected on the support stand 110 adheres to the upper end part of case 13C. A cable (not shown) for outputting image data of a photographed image extends from the lower end of the case 13C. This cable passes through the base portion 106 and is connected to the vehicle sensing portion 5. Yes. An incident portion 14C is fixed to the upper end portion of the case 13C.

  The incident portion 14C is provided as a portion where the light from the optical member 108 is incident, and is configured by, for example, a lens. The incident portion 14C faces upward and faces the optical member 108 in the vertical direction Z1. The image incident on the incident unit 14C is incident on the image sensor included in the first imaging unit 11C. 11C of 1st imaging | photography parts output the 1st image data produced | generated by the image pick-up element etc. to the vehicle detection part 5. FIG. A second imaging unit 12C is arranged so as to line up with the first imaging unit 11C in the traveling direction D1.

  The second imaging unit 12C generates second image data by capturing an image incident from the optical member 108. The second imaging unit 12C is disposed at the second position P2 on the support base 110. At the second position P2, the second photographing unit 12C can photograph only the second measurement area 3C out of the first measurement area 2C and the second measurement area 3C. The second position P2 is a position below the second guide part 122, for example.

  The case 15C of the second imaging unit 12C is fixed to the support base 110. The case 15C is formed in an elongated shape in the vertical direction Z1, and the upper end of the case 15C is distanced from the support base 110. Thereby, it can suppress that the foreign material collected on the support stand 110 adheres to the upper end part of case 15C. A cable (not shown) for outputting image data of a photographed image extends from the lower end portion of the case 15C. This cable passes through the base portion 106 and is connected to the vehicle sensing portion 5. Yes. An incident portion 16C is fixed to the upper end portion of the case 15C.

  The incident portion 16C is provided as a portion where light from the optical member 108 is incident, and is configured by, for example, a lens. The incident portion 16C faces upward, and faces the optical member 108 in the vertical direction Z1. The image incident on the incident unit 16C is incident on the image sensor included in the second imaging unit 12C. The second imaging unit 12C outputs the second image data generated by the image sensor or the like to the vehicle sensing unit 5.

  The first imaging unit 11C and the second imaging unit 12C are surrounded by the housing 113. The housing 113 is provided to prevent foreign matters from adhering to the first imaging unit 11C and the second imaging unit 12C. The housing 113 is formed in a cylindrical shape that extends vertically in parallel with the first shaft 107, and is formed in a cylindrical shape in the present embodiment. The housing 113 is formed of, for example, a steel pipe. Note that the housing 113 may be formed using a non-transparent material or may be formed using a transparent material. The lower end portion of the housing 113 is fixed to the outer peripheral portion at the upper end of the base portion 106. In the vertical direction Z1, the position of the upper end portion of the housing 113 is higher than the positions of the incident portions 14C and 16C of the imaging units 11C and 12C. As a result, the housing 113 surrounds a part of the first shaft 107, most of the second shaft 109, the support base 110, and the imaging units 11C and 12C.

  The housing 113 is provided with a fan 128 as an airflow generating member and a maintenance window 129. The fan 128 is provided to ventilate the inside of the housing 113. For example, one or a plurality of fans 128 are arranged at positions higher than the height positions of the photographing units 11C and 12C in the vertical direction Z1. In the present embodiment, two fans 128 are provided at positions separated from each other in the circumferential direction of the housing 113 and are adjacent to the imaging units 11C and 12C. For example, the fan 128 sucks the inside of the housing 113 to generate an air flow inside the housing 113. As a result, the foreign matter that has entered the inside of the housing 113 is guided by the airflow and discharged to the outside of the housing 113. Instead of the fan 128, another member for airflow generation such as a vent may be provided in the housing 113.

  The window 129 is provided for maintaining members inside the housing 113 such as the photographing units 11C and 12C. One or more windows 129 are arranged below the fan 128. In the present embodiment, the window 129 is disposed below each fan 128 and is adjacent to each imaging unit 11C, 12C. The window 129 is fitted in an opening formed in the housing 113 and can be removed from the opening. The window 129 may be formed using a transparent material, or may be formed using a non-transparent material. For example, when the worker cleans the incident portions 14C and 16C of the photographing units 11C and 12C, the window 129 is removed from the housing 113. Thereby, an operator's arm etc. can be inserted from the exterior of the housing | casing 113 through an opening part inside.

[Optical member selection]
FIG. 8A and FIG. 8B are schematic partial cross-sectional side views of main parts for describing the plurality of optical members 108 and 108C. As shown in FIGS. 8A and 8B, in the present embodiment, the image type vehicle sensor 1C includes a plurality of optical members 108 and 108C. The plurality of optical members 108 and 108 </ b> C can be alternatively attached to the first shaft 107.

  The optical members 108 and 108C have different outer peripheral surface shapes. Specifically, in the optical member 108, the inclination angle θ of the generatrix L2 with respect to the central axis L1 is defined. In the optical member 108C, an inclination angle θC of the bus L2C with respect to the central axis L1 is defined. The inclination angles θ and θC are different. For example, the inclination angle θ <θC is set.

  As a result, the first measurement area when the optical member 108C is attached to the first shaft 107, compared to the length of the first measurement area 2C in the traveling direction D1 when the optical member 108 is attached to the first shaft 107. The length of the traveling direction D1 of 2C becomes larger. That is, when the optical member 108 is used among the optical members 108 and 108C, the first measurement area 2C becomes longer.

  On the other hand, compared with the length of the first measurement area 2C in the width direction W1 when the optical member 108 is attached to the first shaft 107, the first measurement area when the optical member 108C is attached to the first shaft 107. The length in the width direction W1 of 2C becomes larger. That is, when the optical member 108C is used among the optical members 108 and 108C, the first measurement area 2C is wide. The same applies to the size of the second measurement area 3C. For example, when the photographing apparatus 4C is installed on a wide road such as one side three lanes, it is preferable to use the optical member 108C among the optical members 108 and 108C.

  The operator can appropriately select the optical member 108 or the optical member 108C according to the size of the area photographed by each of the photographing units 11C and 12C. As described above, in the present embodiment, the optical member 108 of the optical members 108 and 108 </ b> C is attached to the first shaft 107.

[Cleaning of optical components]
Next, the cleaning operation of the optical member 108 will be described. FIG. 9A and FIG. 9B are side views of the main part for explaining the cleaning operation of the optical member 108. As shown in FIG. 9A, dust 201 adheres to a portion of the outer peripheral surface 108a of the optical member 108 that does not face the road 100C, and the outer surface 108a faces the road 100C. The case where the outer peripheral surface 108a of the optical member 108 is cleaned from the state where the dust 202 adheres to the side portion will be described.

  In this case, when cleaning the optical member 108, the worker forms a portion of the outer peripheral surface 108 a of the optical member 108 that forms the first guide portion 121 and the second guide portion 122. A portion other than the portion being cleaned is cleaned by the cleaning member 203. For example, the cleaning member 203 cleans a portion of the outer peripheral surface 108a that does not face the road 100C (not shown). Thereby, foreign matters such as dust 201 adhering to the outer peripheral surface 108a are removed.

  Next, the worker rotates the optical member 108 around the first shaft 107 by a predetermined angle as shown in FIG. Next, the worker cleans the outer peripheral surface 108 a of the optical member 108 with the cleaning member 203 except for the portion where the first guide portion 121 is formed and the portion where the second guide portion 122 is formed. . For example, the cleaning member 203 cleans a portion of the outer peripheral surface 108a that does not face the road 100C. Thereby, foreign matters such as dust 202 attached to the outer peripheral surface 108a are removed. Thereby, the cleaning operation of the outer peripheral surface 108a of the optical member 108 is completed.

  Note that the image type vehicle detector 1CC shown in FIG. 6A includes a photographing device 4CC and a vehicle detection unit 5. The imaging device 4CC is installed on the upper part of the portal column 100a installed on the road 100C. The imaging device 4CC has a configuration similar to that of the imaging device 4C except that the length of the first shaft 107 and the length of the housing 113 are different. As described above, the image-type vehicle sensor 1C and the image-type vehicle having a total height corresponding to the installation height from the road 100C can be obtained with a simple configuration in which the length of the first shaft 107 and the length of the housing 113 are made different. The sensor 1CC can be manufactured.

  In addition, in this Embodiment, although the structure which uses the vehicle detection part 5 was demonstrated, it is not limited to this. Instead of the vehicle sensing unit 5, a vehicle sensing unit 5B may be used.

  As described above, in the image type vehicle sensor according to the third embodiment of the present invention, the optical member 108 is provided. The optical member 108 includes a first guide 121 for optically guiding the first image 21C when the first measurement area 2C is viewed from the front side of the first measurement area 2C to the first photographing unit 11C, and a second And a second guide unit 122 for optically guiding the second image 22C when the measurement area 3C is viewed from the rear side of the second measurement area 3C to the second imaging unit 12C.

  Thereby, the first image 21C and the second image 22C are guided to the corresponding first imaging unit 11C and second imaging unit 12C by the optical member 108, respectively. Therefore, the first imaging unit 11C and the second imaging unit 12C can indirectly image the first measurement area 2C and the second measurement area 3C via the optical member 108, respectively. Therefore, the first imaging unit 11C and the second imaging unit 12C do not need to directly enter sunlight. Thereby, it can suppress that unnecessary light injects into the 1st imaging | photography part 11C and the 2nd imaging | photography part 12C. Accordingly, it is possible to further suppress a decrease in vehicle detection accuracy caused by strong light such as sunlight.

[Fourth embodiment]
FIG. 10 is a cross-sectional view showing a photographing device 4D of an image type vehicle sensor according to the fourth embodiment of the present invention, and a part thereof is shown by a side. FIG. 11 is a functional block diagram of the vehicle sensing unit 5D of the image type vehicle sensor according to the fourth embodiment of the present invention.

  As shown in FIGS. 10 and 11, the image type vehicle sensor according to the fourth embodiment of the present invention is different from the image type vehicle sensor according to the third embodiment mainly in the following two points. It is. That is, (1) the imaging device 4D captures both the first image 21C and the second image 22C simultaneously by one imaging unit 150, and (2) the vehicle sensing unit 5D includes the first image 21C and the second image 21C. The point is that the sensing processing of each vehicle 101 is performed based on the image data of the photographed image obtained by photographing both of the images 22C.

  In the imaging device 4D, the imaging unit 150 has the same configuration as the first imaging unit 11C, except that the imaging unit 150 is arranged at the third position P3. At the third position P3, the photographing unit 150 can photograph both the first image 21C reflected by the first guide unit 121 and the second image 22C reflected by the second guide unit 122 of the optical member 108. . The third position P3 is, for example, the center position of the optical member 108 in the traveling direction D1, and the first shaft 107 is a position aligned in the width direction W1 of the road 100C. In this way, the first guide 121 of the optical member 108 optically guides the first image 21C to the photographing unit 150, and the second guide 122 122 optically guides the second image 22C to the photographing unit 150. To do.

  The vehicle sensing unit 5D includes an image input unit 151, an image correction unit 152, a selection unit 52, an image sensing processing unit 51, a sensing data transmission unit 36, a timing unit 37, a maintenance information input unit 38, and an image. And a data transmission unit 39.

  The image input unit 151 outputs captured image data as image data captured by the image capturing unit 150. The image input unit 151 outputs the captured image data to the image correction unit 152.

  FIG. 12A and FIG. 12B are diagrams for explaining the image correction processing in the image correction unit 152. As shown in FIGS. 11, 12A, and 12B, the image correction unit 152 is provided to correct captured image data. Specifically, the image 153 including both the first image 21C and the second image 22C is reflected on the outer peripheral surface 108a of the optical member 108. The imaging unit 150 captures the image 153 to generate captured image data. The image correction unit 152 reads the captured image data.

  As shown in FIG. 11 and FIG. 12B, the image correction unit 152 corrects the captured image data, thereby correcting the first image data as the image data of the captured image of the first image 21C, and The image is separated into second image data as image data of the captured image of the second image 22C.

  The image correction unit 152 outputs the first image data and the second image data to the image data transmission unit 39 and also to the selection unit 52.

[Vehicle sensing operation in the image type vehicle sensor according to the fourth embodiment]
FIG. 13 is a flowchart for explaining a vehicle sensing operation in the image type vehicle sensor according to the fourth embodiment. This vehicle sensing operation will be described with reference to FIGS. 10 to 12 in addition to FIG. The captured image data from the imaging unit 150 is output to the image input unit 151, and further output from the image input unit 151 to the image correction unit 152 (step S41).

  Next, the image correction unit 152 performs image correction processing (step S42). The image correction unit 152 generates first image data and second image data based on the captured image data. Then, the image correction unit 152 outputs the first image data and the second image data to the selection unit 52 (step S43).

  Subsequent steps S122 to S129 are the same as steps S22 to S29 (see FIG. 5) of the vehicle sensing operation in the image type vehicle sensor according to the second embodiment, and thus description thereof is omitted.

  In the image type vehicle sensor according to the fourth embodiment of the present invention, an optical member 108 and a single photographing unit 150 for photographing an image 153 from the optical member 108 are provided. The optical member 108 includes a first guide 121 for optically guiding the first image 21C when the first measurement area 2C is viewed from the front side of the first measurement area 2C to the photographing unit 150, and a second measurement. A second guide unit 122 for optically guiding the second image 22C when the area 3C is viewed from the rear side of the second measurement area 3C to one photographing unit 150. The first image data is based on the first image 21C, and the second image data is based on the second image 22C.

  Thereby, the direction from the imaging unit 150 toward the first measurement area 2C and the direction from the imaging unit 150 toward the second measurement area 3C are opposite in the component parallel to the traveling direction D1 of the road 100C. . Therefore, even if the amount of sunlight reflected in the first image specified by the first image data is large, the amount of sunlight reflected is small in the second image specified by the second image data. Two images can be obtained. Similarly, for example, even if the amount of sunlight reflected in the second image specified by the second image data is large, the amount of sunlight reflected is small in the first image specified by the first image data. A first image can be obtained. That is, during the time when the morning sun rises, the sensing process of the vehicle 101 can be performed based on the first image data of the first image of the first image and the second image with a small amount of reflected sunrise. . In addition, during the sunset time, the vehicle 101 can be detected based on the second image data of the second image with the least amount of sunset reflected out of the first image and the second image. . As a result, the vehicle 101 can be detected based on the image data of an image in which direct sunlight is suppressed from being excessively reflected in both the time when the sun rises and the time when the sunset falls. it can. Therefore, it is possible to suppress a decrease in vehicle sensing performance caused by strong light such as sunlight. The first image 21C and the second image 22C are guided to the photographing unit 150 by the optical member 108, respectively. Thereby, the imaging unit 150 can indirectly image the first measurement area 2C and the second measurement area 3C via the optical member 108. Therefore, for example, the photographing unit 150 does not need to directly enter sunlight. Thereby, it can suppress that unnecessary light injects into the imaging | photography part 150. FIG. Accordingly, it is possible to further suppress a decrease in vehicle detection accuracy caused by strong light such as sunlight. Furthermore, the first measurement area 2 </ b> C and the second measurement area 3 </ b> C can be photographed by one photographing unit 150. Thereby, it is not necessary to provide two photographing units 150, and the manufacturing cost of the image type vehicle sensor can be further reduced. In addition, when one of the part where the first image 21C is photographed and the part where the second image 22C is photographed is cleaned in the photographing unit 150, the image data obtained from the other is used. The vehicle sensing process can be continued. Therefore, even when there is only one photographing unit 150, it is possible to suppress interruption of processing for sensing the vehicle 101.

[Fifth Embodiment]
FIG. 14 is a functional block diagram of the vehicle sensing unit 5E of the image type vehicle sensor according to the fifth embodiment of the present invention. As shown in FIG. 14, the vehicle detection unit 5E of the image type vehicle detector according to the fifth embodiment of the present invention is different from the vehicle detection unit 5D of the image type vehicle sensor according to the fourth embodiment. The point is that vehicle detection processing is performed by two image detection processing units.

  The vehicle detection unit 5E includes an image input unit 151, an image correction unit 152, a first image detection processing unit 32, a second image detection processing unit 34, a selection unit 35, a detection data transmission unit 36, and a timing unit. 37, a maintenance information input unit 38, and an image data transmission unit 39.

  In the present embodiment, the image correction unit 152 outputs the generated first image data to the vehicle head point detection unit 41 of the first image detection processing unit 32. In addition, the image correction unit 152 outputs the generated second image data to the vehicle tail point detection unit 43 of the second image detection processing unit 34. In addition, the image correction unit 152 outputs the first image data and the second image data to the image data transmission unit 39.

  The configuration of the first image detection processing unit 32, the second image detection processing unit 34, the selection unit 35, the detection data transmission unit 36, the timing unit 37, the maintenance information input unit 38, and the image data transmission unit 39 of the vehicle detection unit 5E is as follows. Since it is the same as that of the structure corresponding to the vehicle detection part 5 (refer FIG. 2) in 1st Embodiment of this invention, detailed description is abbreviate | omitted.

[Vehicle sensing operation in the image type vehicle sensor according to the fifth embodiment]
FIG. 15 is a flowchart for explaining a vehicle sensing operation in the image type vehicle sensor according to the fifth embodiment. This vehicle sensing operation will be described with reference to FIG. 14 as appropriate in addition to FIG.

  The captured image data from the imaging unit 150 is output to the image input unit 151, and is further output from the image input unit 151 to the image correction unit 152 (step S51). Next, the image correction unit 152 performs image correction processing (step S52). The image correction unit 152 generates first image data and second image data based on the captured image data output from the imaging unit 150. Then, the image correction unit 152 outputs the first image data and the second image data to the vehicle head point detection unit 41 and the vehicle rear point detection unit 43, respectively (step S53).

  Since subsequent steps S112 to S116 are the same as steps S12 to S16 (see FIG. 3) of the vehicle sensing operation in the image type vehicle sensor according to the first embodiment, the description thereof is omitted.

[Modification]
In the image-type vehicle detector according to the embodiment of the present invention, the configuration in which the image data used for vehicle detection is changed in association with the rising time zone, the sunset time zone, or the maintenance period has been described. However, the present invention is not limited to this. For example, when the lens of one of the two imaging units 11 and 12 becomes very dirty, the image data for vehicle detection may be acquired using the image data from the other imaging unit. Good. Thereby, it is possible to easily adjust the timing of the cleaning operation of each of the imaging units 11 and 12 without interrupting the imaging for vehicle detection. Therefore, the operation of the image type vehicle detector can be performed more flexibly. In addition, adjustment of said cleaning time includes adjustment of the schedule and time slot | zone which considered the weather. The photographing units 11C and 12C are the same as the photographing units 11 and 12.

  In addition, in the image type vehicle detector according to the embodiment of the present invention, either the first image data or the second image data is used for vehicle detection, and regardless of this, the first image data and the second image data are used. Although the configuration in which at least one of these is output for monitor display of the central processing unit 102 has been described, the present invention is not limited to this. For example, one of the first image data and the second image data may be used for vehicle detection, and the other may be output for monitor display of the central processing unit 102.

  In addition, any one of the first image data and the second image data may be used for vehicle detection and output for monitor display of the central processing unit 102. In this case, only one of the photographing units 11 and 12 can be used for photographing for vehicle detection and photographing for monitor display. Therefore, even if the other of the photographing units 11 and 12 is out of order, it is possible to perform photographing for vehicle detection and photographing for monitor display. As a result, the operation of the image type vehicle detector can be performed more flexibly. The same applies to the imaging units 11C and 12C.

  In the image type vehicle sensor according to the embodiment of the present invention, the image data used for vehicle detection is based on time regardless of the actual value of the illuminance of the sun in the first image 21 and the second image 22. Although the configuration for switching has been described, the present invention is not limited to this. For example, the value of the illuminance of the sun in the first image 21 and the second image 22 may be measured, and the image data used for vehicle sensing may be switched based on the measured value. The same applies to the first image 21C and the second image 22C.

  In the image type vehicle detector according to the embodiment of the present invention, the configuration in which the selection unit 35 or 52 determines which of the first image data and the second image data is used for vehicle detection has been described. However, the present invention is not limited to this. For example, a manual switch for setting which of the first image data and the second image data is used for vehicle detection may be provided.

  In the image type vehicle sensor according to the embodiment of the present invention, the configuration in which both the photographing units 11 and 12 are always driven has been described. However, the present invention is not limited to this. For example, a manual switch for stopping the operation of the photographing units 11 and 12 may be provided in the central processing unit 102 or the vehicle sensing unit. In this case, it is possible to perform maintenance such as cleaning, adjustment of the orientation or position, confirmation of the presence or absence of an abnormality, and repair and replacement work for one of the photographing units 11 and 12 in which the operation is stopped. . In this case, on the other of the photographing units 11 and 12 where the operation is not stopped, photographing for vehicle sensing and monitoring display of the central processing unit 102 can be performed. When the maintenance work is completed, the manual switch is operated to restart the operation of one of the photographing units. The same applies to the imaging units 11C and 12C.

  In the image type vehicle detector according to the embodiment of the present invention, the first sensing data and the second sensing data are not particularly associated with each other. However, the present invention is not limited to this. For example, more accurate sensing data may be output by comparing the first sensing data and the second sensing data.

  Furthermore, in the image type vehicle sensor according to the embodiment of the present invention, the configuration in which there is no particular association between the image type vehicle sensors in the case where a plurality of image type vehicle sensors are provided has been described. It is not limited to. For example, a plurality of image-type vehicle detectors are provided between interchanges (ICs) on a highway, and the detection data of each image-type vehicle detector can be compared so that more accurate detection data can be output. May be.

  Further, in the image type vehicle sensor according to the embodiment of the present invention, the imaging units 11 and 12 of the imaging device 4 have been described as being arranged opposite to each other in the traveling direction D1 of the road 100. It is not limited. For example, the imaging units 11 and 12 may be aligned in the same direction in the traveling direction D1. In this case, a reflecting member that reflects the light from the second measurement area 3 to the incident portion 16 is disposed in one of the photographing portions 11 and 12, for example, in the vicinity of the incident portion 16 of the photographing portion 12. The reflecting member is, for example, a mirror. Thereby, the second measurement area 3 can be photographed by the photographing unit 12.

  In the image type vehicle sensor according to the embodiment of the present invention, the configuration using the mirror that reflects light as the optical member 108 has been described. However, the present invention is not limited to this. For example, the optical member may be a member that refracts light, such as a prism.

  In the image type vehicle sensor according to the embodiment of the present invention, the configuration in which the optical member 108 has a truncated cone shape has been described. However, the present invention is not limited to this. For example, the reflecting member may have a polygonal frustum shape or a hemispherical shape that bulges downward.

  In the image type vehicle sensor according to the embodiment of the present invention, the configuration in which the plurality of optical members 108 and 108C are prepared has been described, but the present invention is not limited to this. For example, the reflection member may be one type.

  Further, in the image type vehicle sensor according to the embodiment of the present invention, a configuration in which the incident portions 14C and 16C are arranged upward with respect to each of the photographing portions 11C and 12C for photographing the light from the optical member 108 will be described. However, the present invention is not limited to this. For example, the incident portions 14C and 16C may face the horizontal direction. The incident portions 14C and 16C only have to be arranged so that the first image 21C and the second image 22C from the optical member 108 can enter, and the direction and the arrangement location are not particularly limited.

  In the image type vehicle sensor according to the embodiment of the present invention, the optical member 108 has been described as rotating around the first shaft 107 by the operator's manual operation, but the present invention is not limited to this. For example, the optical member 108 may be rotated by providing a displacement mechanism including an electric motor and rotating the first shaft 107 by the displacement mechanism. In this case, for example, an operator periodically looks at images captured by the image capturing units 11C and 12C or the image capturing unit 150 using the monitor of the central processing unit 102. Then, when the operator determines that the degree of unclearness of the image is large, the optical member 108 can be rotated. As a result, a portion of the outer peripheral surface 108a of the optical member 108 that does not face the road 100C and that is relatively less contaminated faces the road 100C, and this portion is referred to as the first guide portion 121 and the second guide portion. 122 can be used.

  In the image type vehicle detector according to the embodiment of the present invention, the first photographing units 11 and 11C are arranged to photograph the west side of the roads 100 and 100C, and the second photographing units 12 and 12C Although the structure arrange | positioned so that the east side of 100,100C may be image | photographed was demonstrated, it is not limited to this. For example, the first photographing units 11 and 11C may be arranged so as to photograph the east side of the roads 100 and 100C, and the second photographing units 12 and 12C may be arranged so as to photograph the west side of the roads 100 and 100C. . In this case, the first photographing period is a period in which the sunset intensity in the second image specified by the second image data is larger than the sunset intensity in the first image specified by the first image data. Is set. In addition, the second shooting period is a period in which the intensity of the morning sun in the first image specified by the first image data is greater than the intensity of the morning sun in the second image specified by the second image data. Is set.

  In the image type vehicle detector according to the embodiment of the present invention, as shown in FIGS. 2 and 14, the selection unit 35 has been described as being included in the vehicle detection units 5 and 5E. However, the present invention is not limited to this. Not what you want. For example, the selection unit 35 and the sensing data transmission unit 36 may be included in the central processing unit 102. In this case, the central processing unit 102 constitutes a part of the image type vehicle sensor. In this case, both the detection processing result of the first image detection processing unit 32 and the detection processing result of the second image detection processing unit 34 are transmitted to the central processing unit 102.

  Further, in the image type vehicle sensor according to the embodiment of the present invention, as shown in FIGS. 4 and 11, the selection unit 52 has been described as being included in the vehicle detection units 5B and 5D, but the present invention is not limited thereto. Not what you want. For example, the selection unit 52, the image detection processing unit 51, and the detection data transmission unit 36 may be included in the central processing unit 102. In this case, the central processing unit 102 constitutes a part of the image type vehicle sensor. In this case, the detection processing of the image detection processing unit 51 is performed in the central processing unit 102.

  In the image type vehicle sensor according to the embodiment of the present invention, the image correction unit 152 uses the first image data and the second image based on the captured image data of the image 153 generated by the imaging unit 150. The configuration for dividing data has been described. However, the present invention is not limited to this. For example, the vehicle sensing units 5D and E select the first image data or the second image data from the photographed image data without separating the photographed image data generated by the photographing unit 150, and detect the vehicle 101. Processing may be performed.

  Moreover, although the image type vehicle sensor which concerns on embodiment of this invention demonstrated the structure installed in the road extended east and west, it is not limited to this. The traveling direction of the road where the image type vehicle sensor is installed is not particularly limited.

  Moreover, although the image type vehicle sensor which concerns on embodiment of this invention demonstrated the structure arrange | positioned in the place exposed to sunlight, it is not limited to this. The image-type vehicle sensor may be disposed in the tunnel. In this case, for example, when the illumination in the tunnel is directly radiated to one imaging unit or one guide part of the optical member, the image of the vehicle is used to capture the image from the other guide unit. Sensing processing can be performed.

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1,1C Image type vehicle detector 2,2C 1st measurement area 3,3C 2nd measurement area 8,8C Optical member 11,11C 1st imaging | photography part 12,12C 2nd imaging | photography part 21C 1st image 22C 2nd image 32 First image sensing processor (first processor)
34 Second image sensing processor (second processor)
35 selection unit 39 image data transmission unit (image data output unit)
51 Image sensing processor (one processor, first processor, second processor)
52 selection unit 100, 100C road 101 vehicle 121 first guide unit 122 second guide unit 150 imaging unit (one imaging unit)
152 Image correction unit (correction unit)
D1 Direction of travel

Claims (12)

Based on the first image data obtained by photographing one or a plurality of vehicles passing through the first measurement area on the road along a predetermined traveling direction, a sensing process for each of the vehicles can be performed. One processing unit;
It is possible to perform the sensing process for each vehicle based on the second image data obtained by photographing the second measurement area on the road to which each vehicle that has passed through the first measurement area is taken. A second processing unit;
A selection unit capable of selecting which of a sensing process result in the first processing unit and a sensing process result in the second processing unit is to be output;
An image-type vehicle detector. The first processing unit and the second processing unit can perform sensing processing of each vehicle in parallel,
The image type vehicle sensor according to claim 1, wherein the selection unit is capable of outputting either a sensing process result in the first processing unit or a sensing process result in the second processing unit. The first processing unit and the second processing unit are configured by one processing unit,
The selection unit can instruct the one processing unit to perform sensing processing of each vehicle based on which of the first image data and the second image data. The image type vehicle sensor according to claim 1.   The image type vehicle sensor according to any one of claims 1 to 3, further comprising an image data output unit that outputs at least one of the first image data and the second image data. A first photographing unit for photographing each vehicle passing through the first measurement area from the front side of each vehicle;
A second photographing unit for photographing each vehicle passing through the second measurement area from the rear side of each vehicle;
The image type vehicle sensor according to any one of claims 1 to 4, further comprising:   The image-type vehicle detector according to claim 5, wherein the first photographing unit and the second photographing unit are disposed in opposite directions with respect to the traveling direction. An optical member;
The optical member includes a first guide unit for optically guiding a first image of the first measurement area viewed from the front side of the first measurement area to the first photographing unit, and the second measurement area. The image-type vehicle detector according to claim 5, further comprising: a second guide unit for optically guiding a second image of the second measurement area viewed from the rear side of the second measurement area to the second imaging unit. An optical member;
A single photographing unit for photographing an image from the optical member, and
The optical member includes a first guide unit for optically guiding a first image of the first measurement area viewed from the front side of the first measurement area to the one photographing unit, and the second measurement area. A second guide unit for optically guiding a second image of the second measurement area viewed from the rear side to the one photographing unit,
The image according to any one of claims 1 to 4, wherein the first image data is based on the first image, and the second image data is based on the second image. Type vehicle detector.   The selection unit outputs a sensing process result of the first processing unit in a predetermined first period, and a sensing process result of the second processing unit in a predetermined second period different from the first period. The image type vehicle sensor according to any one of claims 1 to 8, wherein: In the first period, the intensity of the sunrise or sunset in the second image specified by the second image data is greater than the intensity of the sunrise or sunset in the first image specified by the first image data. Including one shooting period,
In the second period, the intensity of the sunset or sunrise in the first image specified by the first image data is greater than the intensity of sunset or sunrise in the second image specified by the second image data. The image type vehicle sensor according to claim 9, comprising two shooting periods. The first period includes a first maintenance period for maintaining a second imaging unit that images the second measurement area,
11. The image type vehicle sensor according to claim 9, wherein the second period includes a second maintenance period for maintaining the first photographing unit that photographs the first measurement area. On the computer,
Accepting first image data obtained by photographing one or more vehicles passing through a first measurement area on a road along a predetermined traveling direction;
Accepting second image data obtained by photographing the second measurement area on the road to which each of the vehicles that have passed through the first measurement area is taken; and
Outputting a sensing process result obtained by performing a sensing process on each vehicle based on one of the first image data and the second image data;
A vehicle sensing program for executing

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