JPWO2008010308A1 - License plate information acquisition apparatus and license plate information acquisition method - Google Patents

Abstract

The license plate information acquisition device detects a vehicle that is about to pass a front point from detection data obtained by a vehicle detection sensor such as a camera, gives vehicle identification information, and passes until the vehicle passes a rear point from the front point. The vehicle identification information is added to the vehicle, the vehicle is tracked, and the front license plate information acquired from the image data of the front camera when the vehicle enters the front point is associated with the vehicle identification information. When the vehicle enters the rear point, similarly, the rear license plate information and the vehicle identification information are held in association with each other, the vehicle identification information is compared, and the same vehicle identification information is given. Correlate front license plate information and rear license plate information.

Description

  The present invention relates to a license plate information acquisition device, a license plate information acquisition method, and a license plate information acquisition program.

  Conventionally, the number plates of the front and rear vehicles in motion are imaged, and the number plate information read on the front and rear number plates is read from the image by character recognition. A technique for associating plate information with the same vehicle has been devised.

  For example, Patent Document 1 discloses a technique described below. That is, as shown in FIG. 19A, when the vehicle 1901 enters the front imaging point 1902, the front license plate reading device 1903 reads the front part read by imaging the front license plate of the vehicle 1901. The license plate information (for example, serial number “12-34”, etc.) is stored in the front license plate information storage unit 1905 of the information processing apparatus 1904 in association with the time T1 when the front license plate information is read. The sensor 1906 measures the speed V (m / sec) of the vehicle and the total length l (m) of the vehicle.

  Here, the information processing apparatus 1904 sets the rear imaging point 1907 from V (m / sec), l (m), and a known distance L (m) from the front imaging point 1902 to the rear imaging point 1907. An expected time T2 at which the vehicle enters is obtained.

  Then, as shown in FIG. 19B, when the vehicle 1901 enters the rear imaging point 1907, the rear license plate reader 1908 similarly reads the license plate read by imaging the rear license plate of the vehicle 1901. The information is stored in the rear license plate information storage unit 1909 of the information processing apparatus 1904 in association with the time T3 when the license plate information is read.

  Then, as shown in FIG. 19C, the information processing apparatus 1904, when the time T3 is within the range of the time T2 ± ΔT obtained by adding or subtracting the error ΔT to the expected time T2, reads before the time T1. The part number plate information and the rear part number plate information read at time T3 are associated with each other as the same vehicle, and stored in the associated number plate information storage unit 1910 that the self part number is associated with. The information processing apparatus 1904 determines whether or not the vehicle is a violation vehicle by collating the associated front and rear license plate information, and warns on the spot or warns at a later date. Realized.

JP 2003-228793 A

  By the way, the above-described conventional technology has a problem that the front license plate information and the rear license plate information cannot be associated with each other depending on the movement of the vehicle. For example, when the vehicle pauses in the section between the front imaging point and the rear imaging point, re-starts and enters the rear imaging point, the estimated time of arrival at the rear imaging point of the vehicle Therefore, the front license plate information cannot be associated with the rear license plate information with consistency. In addition, if another vehicle overtakes a temporarily stopped vehicle and enters the rear imaging point at a time within the range where the error is adjusted in the estimated time of arrival at the rear imaging point of the vehicle, the front number of the overtaken vehicle Since the plate information and the rear license plate information of the overtaken vehicle are associated with each other, an incorrect association is performed and the association cannot be performed with consistency. Furthermore, application to multiple lanes is not always consistent because the errors caused by the vehicle changing lanes cannot be determined unambiguously, and multiple front and rear imaging points must be associated with consideration of vehicle lane changes. Could not be associated with sex.

  Accordingly, the present invention has been made to solve the above-described problems of the prior art, and the front and rear license plate information is consistent with those of the same vehicle without being influenced by the movement of the vehicle. It is an object to provide a license plate information acquisition device, a license plate information acquisition method, and a license plate information acquisition program that can be associated with each other.

  In order to solve the above-described problems and achieve the object, the invention according to claim 1 acquires the front license plate information displayed on the front license plate of the vehicle passing through the front point, and the rear point. A license plate information acquisition device that acquires rear license plate information displayed on a rear license plate of a passing vehicle and associates the front license plate information and the rear license plate information with each other, and tries to pass the front point The vehicle is detected and the vehicle is tracked while maintaining the state in which the vehicle identification information for uniquely identifying the vehicle is given to the vehicle until the detected vehicle passes from the front point to the rear point. Vehicle tracking means, and the vehicle tracking means for the vehicle from which the front license plate information is acquired Front information holding means for acquiring vehicle identification information that is acquired and associating and holding front license plate information and vehicle identification information acquired from the vehicle, and a vehicle from which the rear license plate information is acquired. A rear information holding means for acquiring the vehicle identification information given by the vehicle tracking means and holding the rear license plate information and the vehicle identification information acquired from the vehicle in association with each other, the front information holding means, The vehicle identification information held in the rear information holding means is compared, and the front number plate information to which the same vehicle identification information is assigned and the front rear correspondence means for associating the rear number plate information are provided. It is characterized by.

  Further, in the invention according to claim 2, in the above invention, the vehicle tracking means tries to pass the front point by processing an image obtained by imaging an area including the front point and the rear point. And detecting the vehicle to be tracked while keeping the state where the vehicle identification information is given to the vehicle.

  Further, in the invention according to claim 3, in the above invention, the vehicle tracking unit processes the reflected wave returned by the electromagnetic wave transmitted toward the region including the front point and the rear point, While detecting the vehicle which is going to pass the front point, the vehicle is tracked while maintaining the state where the vehicle identification information is given to the vehicle.

  In the invention according to claim 4, in the above invention, the vehicle tracking means images a front license plate of a vehicle passing through the front point on a pillar located between the front point and the rear point. Together with the front license plate information acquisition means for acquiring the front license plate information, and the rear license plate information acquisition means for capturing the rear license plate information by imaging the rear license plate of the vehicle passing through the rear point. The vehicle is installed and detects a vehicle that is about to pass the front point, and the vehicle is tracked while maintaining the state in which the vehicle identification information is given to the vehicle.

  According to a fifth aspect of the present invention, in the above invention, the vehicle tracking means includes a front license plate of a vehicle passing through the front point on a column located upstream or downstream from the front point and the rear point. Front license plate information acquisition means for imaging and acquiring the front license plate information, and rear license plate information acquisition for acquiring the rear license plate information by imaging the rear license plate of the vehicle passing through the rear point The vehicle is installed separately from the means, and detects a vehicle that is about to pass through the front point, and tracks the vehicle while maintaining a state in which the vehicle identification information is given to the vehicle.

  In the invention according to claim 6, in the above invention, the front license plate information and the rear license plate information are acquired for each lane in a plurality of lanes, and the vehicle tracking means A state in which a vehicle that tries to pass the front point is detected for each lane, and the vehicle identification information is given to the vehicle until the detected vehicle passes a rear point of any lane from the front point. The front information holding means and the rear information holding means hold the license plate information and the vehicle identification information in association with each lane, and the front / rear association means Front number play in which the same vehicle identification information is given by comparing the vehicle identification information of the same lane held in the front information holding means and the rear information holding means When there is information and rear license plate information, the front license plate information and rear license plate information are associated with each other, and there is no front license plate information and rear license plate information to which the same vehicle identification information is given. For comparing the vehicle identification information of the different lanes held in the front information holding means and the rear information holding means, the front license plate information and the rear license plate information to which the same vehicle identification information is given are It is characterized by associating.

  The invention according to claim 7 is the color information and shape information of the vehicle from which the front license plate information is acquired, and the color information and shape of the vehicle from which the rear license plate information is acquired. Color shape information acquisition means for acquiring information respectively, wherein the front information holding means and the rear information holding means are adapted to obtain the color information and shape information acquired by the color shape information acquisition means from the license plate information and the vehicle. The front rear part association unit compares the vehicle identification information, the color information, and the shape information held in the front part information holding unit and the rear part information holding unit, and stores the same vehicle. Associating front license plate information with identification information, color information and shape information with rear license plate information And features.

  Further, in the invention according to claim 8, in the above invention, time information indicating the time when the front license plate information is acquired and time information indicating the time when the rear license plate information is acquired are respectively acquired. Further comprising time information acquisition means, wherein the front information holding means and the rear information holding means hold the time information acquired by the time information acquisition means in association with the license plate information and the vehicle identification information, The front / rear association means compares the vehicle identification information and time information held in the front information holding means and the rear information holding means, and is given the same vehicle identification information or adjacent time information. The front license plate information and the rear license plate information are associated with each other.

  The invention according to claim 9 is the above invention, wherein the front license plate information and the rear license plate information associated with each other by the front / rear associating means are compared with each other to determine whether they belong to the same vehicle. It is further characterized by further comprising collation means for collating these.

  According to a tenth aspect of the present invention, in the above invention, the front number plate information displayed on the front number plate of the vehicle passing through the front point is acquired and the rear number of the vehicle passing through the rear point is acquired. It is a license plate information acquisition program that acquires the rear license plate information displayed on the plate, associates the front license plate information and the rear license plate information, detects a vehicle passing through the front point, and Until the detected vehicle passes from the front point to the rear point, a vehicle tracking procedure for tracking the vehicle while maintaining a state in which vehicle identification information for uniquely identifying the vehicle is given to the vehicle; Given to the vehicle from which the front license plate information is acquired by the vehicle tracking procedure. A front information holding procedure for acquiring vehicle identification information and associating and holding the front license plate information and the vehicle identification information acquired from the vehicle, and the vehicle for which the rear license plate information is acquired. A rear information holding procedure for acquiring the vehicle identification information given by the tracking procedure and holding the rear license plate information and the vehicle identification information acquired from the vehicle in association with each other, and the front information holding procedure and the rear information holding. The vehicle rearrangement procedure for comparing the vehicle identification information held in the procedure and associating the front license plate information and the rear license plate information to which the same vehicle identification information is assigned is provided. To do.

  Moreover, the invention which concerns on Claim 11 is displayed on the rear number plate of the vehicle which passes the back point while acquiring the front number plate information currently displayed on the front number plate of the vehicle which passes the front point. A license plate information acquisition method for acquiring the rear license plate information and associating the front license plate information and the rear license plate information, detecting a vehicle that is about to pass through the front point, and detecting the vehicle A vehicle tracking step for tracking the vehicle while maintaining a state in which vehicle identification information for uniquely identifying the vehicle is given to the vehicle from the front point to the rear point, and the front number plate The vehicle identification information given by the vehicle tracking process is acquired for the vehicle from which the information is acquired. A front information holding step for holding the front license plate information and the vehicle identification information acquired from the vehicle in association with each other, and a vehicle given by the vehicle tracking step to the vehicle from which the rear license plate information is acquired. A rear information holding step of acquiring identification information and associating and holding rear license plate information and vehicle identification information acquired from the vehicle, and vehicle identification information held in the front information holding step and rear information holding step And a front / rear association step of associating the front license plate information and the rear license plate information to which the same vehicle identification information is assigned.

  According to the first, tenth, or eleventh aspects of the present invention, a vehicle that is about to pass through the front point is detected, and the vehicle is uniquely identified until the detected vehicle passes through the rear point from the front point. The vehicle identification information is assigned to the vehicle for which the front license plate information is acquired, and the front license plate information acquired from the vehicle is retained. Vehicle identification information associated with the vehicle, the vehicle identification information assigned to the vehicle from which the rear license plate information is acquired, and the rear license plate information and vehicle identification information acquired from the vehicle The vehicle identification information is compared, and the front license plate information and the rear license plate information to which the same vehicle identification information is assigned are compared. Since put, without being affected by the movements of the vehicle, it is possible to associate with the integrity of the front and rear license plate information as the same vehicle.

  According to the invention of claim 2, by processing an image obtained by imaging a region including the front point and the rear point, a vehicle that is about to pass the front point is detected, and the vehicle identification information is Since the vehicle is tracked while maintaining the state given to the vehicle, it is possible to track the vehicle even in a situation where a plurality of vehicles are dense, as compared with a method using electromagnetic waves.

  According to the invention of claim 3, while detecting the vehicle which is going to pass the front point by processing the reflected wave returned by the electromagnetic wave transmitted toward the region including the front point and the rear point. Since the vehicle is tracked while maintaining the state in which the vehicle identification information is given to the vehicle, the vehicle can be used even in situations where it is difficult to recognize an image (for example, at night) as compared with a method using image recognition technology. Can be tracked.

  According to the invention of claim 4, the vehicle tracking means captures the front license plate information by imaging the front license plate of the vehicle passing through the front location on the pillar located between the front location and the rear location. It is installed together with the front license plate information acquisition means for acquiring and the rear license plate information acquisition means for acquiring the rear license plate information by imaging the rear license plate of the vehicle passing through the rear point and trying to pass the front point. Since the vehicle is tracked while detecting the vehicle and maintaining the state where the vehicle identification information is given to the vehicle, it is possible to reduce the cost of installation compared to the method of installing the vehicle tracking means at a remote position. It becomes possible.

  According to the invention of claim 5, the vehicle tracking means includes a front camera that images the front license plate of the vehicle passing through the front point on a column located upstream or downstream from the front point and the rear point, and The vehicle is installed separately from the rear camera that images the rear license plate of the vehicle passing through the rear point, and detects the vehicle that is about to pass through the front point and maintains the state in which the vehicle identification information is given to the vehicle. For example, compared to a method in which a vehicle tracking means using a fisheye lens is installed on the same column in order to image the monitoring range, the time taken to correct the image captured by the fisheye lens is reduced. Only the vehicle tracking processing speed can be increased.

  According to the invention of claim 6, the front license plate information and the rear license plate information are acquired for each lane in a plurality of lanes, and a vehicle that is about to pass through the front point for each lane. Until the detected vehicle passes through the rear point of any lane from the front point, the vehicle is tracked while maintaining the state where the vehicle identification information is given to the vehicle, and the license plate information for each lane And vehicle identification information in association with each other, comparing vehicle identification information of the same lane, and if there is front license plate information and rear license plate information to which the same vehicle identification information is assigned, Number plate information and rear number plate information are associated and front number plate information and rear portion to which the same vehicle identification information is assigned When there is no number plate information, the vehicle identification information of different lanes is compared, and the front license plate information and the rear license plate information to which the same vehicle identification information is assigned are associated with each other. Even if the lane is changed, it is possible to associate the front and rear license plate information with consistency as those of the same vehicle, and in comparison with the method of collectively holding information generated in multiple lanes, The processing speed for associating the front license plate information and the rear license plate information can be increased by the amount of time required for the search.

  Further, according to the invention of claim 7, the color information and shape information of the vehicle from which the front license plate information was acquired, and the color information and shape information of the vehicle from which the rear license plate information was acquired, respectively, Front part to which color information and shape information are associated with license plate information and vehicle identification information, and vehicle identification information, color information and shape information are compared, and the same vehicle identification information, color information and shape information are given Since the license plate information and the rear license plate information are associated with each other, there are a plurality of criteria for determining consistency, and the reliability of consistency can be increased.

  According to the invention of claim 8, the time information indicating the time when the front license plate information is acquired and the time information indicating the time when the rear license plate information is acquired are respectively acquired, and the license plate information The vehicle identification information is compared with the vehicle identification information, and the vehicle identification information and the time information are compared, and the front license plate information and the rear license plate information to which the same vehicle identification information or adjacent time information is assigned are associated with each other. Even if tracking cannot be performed, it is possible to associate with consistency based on time information.

  According to the ninth aspect of the present invention, the associated front license plate information and rear license plate information are compared to check whether or not they belong to the same vehicle. Can be increased. That is, since the license plate information acquisition device collates the front license plate information and the rear license plate information in a consistent state, it is possible to increase the accuracy of finding a violation vehicle.

FIG. 1 is a diagram for explaining the outline and features of a license plate information acquisition apparatus. FIG. 2 is a diagram showing an overview of the license plate information acquisition apparatus. FIG. 3 is a block diagram showing the configuration of the license plate information acquisition apparatus. FIG. 4 is a diagram illustrating an example of information stored in the front license plate information storage unit. FIG. 5 is a diagram illustrating an example of reading license plate information. FIG. 6 is a diagram illustrating an example of information stored in the rear license plate information storage unit. FIG. 7 is a diagram illustrating an example of a situation in which a vehicle is tracked. FIG. 8 is a diagram illustrating an example of information stored in the front and rear license plate information storage unit. FIG. 9 is a flowchart showing the flow of the front license plate information generation process. FIG. 10 is a flowchart showing the flow of the rear license plate information generation process. FIG. 11 is a flowchart showing the flow of the vehicle tracking process. FIG. 12 is a flowchart showing the flow of the license plate information association process. FIG. 13 is a flowchart showing the flow of the license plate information matching process. FIG. 14 is a diagram illustrating an overview of the license plate information acquisition apparatus according to the second embodiment. FIG. 15 is a block diagram illustrating the configuration of the license plate information acquisition apparatus according to the second embodiment. FIG. 16 is a flowchart illustrating the flow of the license plate information association processing according to the second embodiment. FIG. 17 is a diagram illustrating an overview of the license plate information acquisition apparatus according to the third embodiment. FIG. 18 is a diagram illustrating a computer that executes a license plate information acquisition program. FIG. 19 is a diagram for explaining a conventional license plate information association processing technique.

Explanation of symbols

1 pillar 2 vehicle 3 forward point 4 backward point 5 pillar 6 first lane forward point 7 first lane backward point 8 second lane forward point 9 second lane backward point 10 license plate information acquisition device 20 front license plate information generation device 21 Front camera 22 Front image temporary storage unit 23 Front license plate image storage unit 24 Front license plate information storage unit 25 Front vehicle detection processing unit 26 Front license plate recognition unit 27 Front license plate information reading unit 30 Rear license plate information generating device 31 Rear camera 32 Rear image temporary storage unit 33 Rear license plate image storage unit 34 Rear license plate information storage unit 35 Rear vehicle detection processing unit 36 Rear license plate recognition unit 37 Rear license plate information reading unit 40 Vehicle Tracking device 41 Fisheye lens camera 4 Monitoring the image storage unit 43 vehicle tracking unit 44 vehicle identification information transmitting unit 50 license plate information matching device 51 front and rear license plate information storage unit 52 sends the correspondence processing section 53 matching unit 54 unit

  Embodiments of a license plate information acquisition apparatus, a license plate information acquisition method, and a license plate information acquisition program according to the present invention will be described below in detail with reference to the accompanying drawings. In the following, the outline and features of the license plate information acquisition device according to the first embodiment, the configuration of the license plate information acquisition device and the flow of processing will be described in order, and then the license plate information acquisition device according to the second embodiment. First, another embodiment will be described.

[Outline and Features of License Plate Information Acquisition Device According to Embodiment 1]
First, the outline and characteristics of the license plate information acquisition apparatus according to the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a diagram illustrating an overview and characteristics of a license plate information acquisition apparatus according to the first embodiment. FIG. 2 is a diagram illustrating an overview of the license plate information acquisition apparatus according to the first embodiment.

  As shown in FIG. 2, the license plate information acquisition device 10 is fixed to the pillar 1 standing on the side of the roadway, and the front camera 21, the rear camera 31, and the fish-eye lens camera 41 have the pillar 1 protruding above the roadway. The license plate information acquisition device 10, the front camera 21, the rear camera 31, and the fisheye lens camera 41 are connected by a dedicated cable.

  The front camera 21 always images the front point 3 that is the imaging area of the front camera 21, and outputs the image data to the license plate information acquisition device 10. The rear camera 31 is similarly the rear camera 31. The rear point 4, which is the imaging area, is always imaged, and the image data is output to the license plate information acquisition device 10. Further, the fisheye lens camera 41 always images a wide area including the front point 3 and the rear point 4. Similarly, the image data is output to the license plate information acquisition apparatus 10.

  Now, the outline of this license plate information acquisition device 10 is to acquire the front license plate information displayed on the front license plate of the vehicle 2 passing through the front point 3 and the vehicle 2 passing through the rear point 4. The rear license plate information displayed on the rear license plate is acquired, and the front license plate information and the rear license plate information are associated with each other. The license plate information acquisition apparatus 10 is mainly characterized in that the license plate information on the front and rear parts is associated with the same vehicle with consistency without depending on the movement of the vehicle.

  Explaining this main feature, the license plate information acquisition device 10 detects a vehicle that is about to pass through the front point 3 and continues until the detected vehicle passes from the front point 3 to the rear point 4. The vehicle is tracked while maintaining the state where the vehicle identification information for uniquely identifying the vehicle is given.

  Specifically, as shown in FIG. 1A, the license plate information acquisition apparatus 10 detects the vehicle 2 that is about to pass the front point 3 by processing the image data received from the fisheye lens camera 41. The vehicle identification information “A” is given (see (1) in FIG. 1A). And as shown to (B), (C), (D) of the figure, the number plate information acquisition apparatus 10 is vehicle identification information "" until the vehicle 2 passes the back point 4 from the front point 3. The vehicle 2 is tracked while maintaining the state of “A”.

  Next, the license plate information acquisition device 10 holds the vehicle identification information given to the vehicle in association with the front license plate information obtained from the vehicle, and is similarly given to the vehicle. The vehicle identification information is stored in association with the rear license plate acquired from the vehicle.

  Specifically, as shown in FIG. 1B, the license plate information acquisition apparatus 10 holds the vehicle 2 (hereinafter referred to as the vehicle “A”) that keeps track of the state to which the vehicle identification information “A” is given. ) Enters forward point 3, front license plate information (for example, serial number “00-11”) acquired by processing image data received from front camera 21 and vehicle identification information “A” Are stored and held in the front license plate information storage unit 24 (see (2) in FIG. 1B).

  As shown in FIG. 1D, the license plate information acquisition device 10 receives the rear number acquired by processing the image data received from the rear camera 31 when the vehicle “A” enters the rear point 4. Plate information (for example, serial number “00-11”) and vehicle identification information “A” are associated with each other and stored in the rear license plate information storage unit 34 (see (3) in FIG. 1D). ).

  Finally, the license plate information acquisition apparatus 10 compares the vehicle identification information and associates the front license plate information and the rear license plate information to which the same vehicle identification information is assigned.

  Specifically, as shown in FIG. 1D, the license plate information acquisition device 10 includes information held in the front license plate information storage unit 24, information held in the rear license plate information storage unit 34, and Are compared based on the vehicle identification information, and the front license plate information “00-11” to which the same vehicle identification information “A” is assigned is associated with the rear license plate information “00-11”. And stored in the front and rear license plate information storage unit 51 (see (4) in FIG. 1D). The license plate information acquisition apparatus 10 collates the associated front license plate information “00-11” with the rear license plate information “00-11” and transmits the collation result to a preset transmission destination. To do.

  For this reason, the license plate information acquisition apparatus 10 according to the first embodiment is not affected by the movement of the vehicle as described above, that is, the vehicle is located between the front imaging point and the rear imaging point. Even if the vehicle is temporarily stopped in the section, if another vehicle overtakes the temporarily stopped vehicle, or if the vehicle changes lanes in multiple lanes, the license plate information on the front and rear Can be associated with consistency as those of the same vehicle.

[Configuration of License Plate Information Acquisition Device According to Embodiment 1]
Next, the configuration of the license plate information acquisition apparatus 10 shown in FIGS. 1 and 2 will be described with reference to FIG. FIG. 3 is a block diagram showing a configuration of the license plate information acquisition apparatus 10. As shown in the figure, the license plate information acquisition device 10 includes a front license plate information generation device 20, a rear license plate information generation device 30, a vehicle tracking device 40, and a license plate information verification device 50. Is done.

  The front license plate information generating device 20 includes a front image temporary storage unit 22, a front license plate image storage unit 23, a front license plate information storage unit 24, a front vehicle detection processing unit 25, and a front unit. A license plate recognition unit 26 and a front license plate information reading unit 27 are provided and connected to the front camera 21. The front license plate information storage unit 24 corresponds to the “front information holding unit” recited in the claims.

  The front camera 21 always images a front point upstream of the roadway and outputs image data of the front point to the front image temporary storage unit 22 in real time. The front image temporary storage unit 22 temporarily stores the image data of the front point received via the front camera 21.

  The front license plate image storage unit 23 stores image data including a front license plate of the vehicle. Specifically, the front license plate image storage unit 23 receives and stores image data including the front license plate from a front license plate recognition unit 26 described later.

  The front license plate information storage unit 24 is a vehicle that is output from the front license plate information acquired from the vehicle and a vehicle identification information transmission unit 44 of the vehicle tracking device 40 to be described later when the vehicle enters the front point. The identification information is stored in association with each other. Specifically, front license plate information and vehicle identification information are received from a front license plate information reading unit 27 described later, and stored in association with each other. For example, as shown in FIG. 4, the front license plate information storage unit 24 stores vehicle identification information “A” and front license plate information “00-11” in association with each other.

  The front vehicle detection processing unit 25 processes the image data of the front point in real time and determines whether or not the vehicle has entered the image. Specifically, the front vehicle detection processing unit 25 reads the image data of the front point from the front image temporary storage unit 22 and recognizes a temporally varying region in the image (background difference or interframe difference). Or the like, or the pattern recognition technology or the like detects the entry of the vehicle in the image, and determines that the vehicle has entered, the image data including the front number plate in the front number plate recognition unit 26 described later. Outputs a signal instructing acquisition of.

  The front license plate recognition unit 26 recognizes the front license plate in the image, cuts out a region including the license plate, and acquires the image data. Specifically, when the front license plate recognition unit 26 receives a signal from the front vehicle detection processing unit 25, the front license plate recognition unit 26 reads the image data of the front point where the vehicle entered from the front image temporary storage unit 22, and the pattern recognition technology. For example, the front license plate in the image is recognized, a region including the license plate is cut out, and the image data is stored in the front license plate image storage unit 23.

  The front license plate information reading unit 27 generates front license plate information from image data including the front license plate. Specifically, the front license plate information reading unit 27 reads image data including the front license plate from the front license plate image storage unit 23, and is written on the front license plate by OCR (Optical Character Reader) technology or the like. Information is read and front license plate information is generated. Further, the front license plate information reading unit 27 receives the vehicle identification information from the vehicle identification information transmitting unit 44 provided in the vehicle tracking device 40 described later, and displays the vehicle identification information and the generated front license plate information in the front part. It is stored in the license plate information storage unit 24.

  For example, as shown in FIG. 5, the front license plate information reading unit 27 converts the serial number that is one of the information described in the front license plate from the image data 701 to text data 702 “79-36”. To generate front license plate information. Here, the front license plate information reading unit 27 reads only the serial number and generates the front license plate information. However, in addition to the serial number, the information written on the license plate, that is, the land transportation branch office code, etc. The application code or the vehicle type code may be read, and any one or more including the serial number may be generated as the front license plate information.

  Returning to the description of FIG. 3, the rear license plate information generation device 30 includes a rear image temporary storage unit 32, a rear license plate image storage unit 33, a rear license plate information storage unit 34, and a rear vehicle detection processing unit 35. The rear license plate recognition unit 36 and the rear license plate information reading unit 37 are connected to the rear camera 31. The rear image temporary storage unit 32, the rear license plate image storage unit 33, the rear vehicle detection processing unit 35, the rear license plate recognition unit 36, and the rear license plate information reading unit 37 are respectively a front image. The same processing as the temporary storage unit 22, the front license plate image storage unit 23, the front vehicle detection processing unit 25, the front license plate recognition unit 26, and the front license plate information reading unit 27 will be described. In the following, only the rear license plate information storage unit 34 will be described. The rear license plate information storage unit 34 corresponds to the “rear information holding unit” recited in the claims.

  The rear camera 31 always images a rear point downstream of the roadway and outputs image data of the rear point to the rear image temporary storage unit 32 in real time.

  The rear license plate information storage unit 34 includes rear license plate information acquired from the vehicle, and vehicle identification information output when the vehicle enters a rear point by the vehicle identification information transmission unit 44 of the vehicle tracking device 40 described later. Are stored in association with each other. Specifically, the rear license plate information and the vehicle identification information are received from the rear license plate information reading unit 37 and stored in association with each other. For example, as shown in FIG. 6, the rear license plate information storage unit 34 stores vehicle identification information “A” and front license plate information “00-11” in association with each other.

  Returning to the description of FIG. 3, the vehicle tracking device 40 includes a monitoring image storage unit 42, a vehicle tracking unit 43, and a vehicle identification information transmission unit 44, and is connected to the fisheye lens camera 41. The vehicle tracking unit 43 corresponds to “vehicle tracking means” recited in the claims.

  The fisheye lens camera 41 always captures a wide area, which is an area including the front point and the rear point, and outputs image data of the wide area to the monitoring image storage unit 42 in real time. The monitoring image storage unit 42 stores image data of a wide area received via the fisheye lens camera 41.

  The vehicle tracking unit 43 detects a vehicle that is about to pass through the front point, and provides vehicle identification information for uniquely identifying the vehicle until the detected vehicle passes from the front point to the rear point. The vehicle is tracked while maintaining the state assigned to.

  Specifically, the vehicle tracking unit 43 reads a wide range of image data from the monitoring image storage unit 42, recognizes a temporally varying region in the image (background difference, interframe difference, etc.), When a vehicle is detected in the image by the pattern recognition technology, the vehicle is tracked by a technology such as an optical flow while giving vehicle identification information to the vehicle. In addition, the vehicle tracking unit 43 transmits the vehicle identification information given to the vehicle and the vehicle identification information to the front license plate information generation device 20 when the vehicle passes the front point or the rear point, respectively. The transmission destination information indicating whether to transmit to the rear license plate information generation device 30 is output to the vehicle identification information transmission unit 44.

  For example, as shown in FIG. 7A, the vehicle tracking unit 43 gives vehicle identification information “A” to the vehicle 801 detected in the image, and tracks the vehicle “A”. Further, since the vehicle “A” passes through the front point, the vehicle tracking unit 43 uses the vehicle identification information “A” and the destination information indicating transmission to the front license plate information generation device 20 as the vehicle. It outputs to the identification information transmission part 44.

  Then, as shown in FIG. 7B, the vehicle tracking unit 43 recognizes the vehicle “A” and continues tracking even when the vehicle 801 is stopped between the front point and the rear point. Here, the vehicle tracking unit 43 detects the vehicle 802 behind the vehicle 801, adds vehicle identification information “B”, and tracks the vehicle “B”.

  As shown in FIG. 7C, the vehicle tracking unit 43 recognizes the vehicle 802 as the vehicle “B” and continues to track the vehicle 802 even when the vehicle 802 overtakes the vehicle 801. 801 is recognized as the vehicle “A” and tracking is continued. The vehicle tracking unit 43 sends the vehicle identification information “B” to the front license plate information generation device 20 when the vehicle “B” passes the front point and the rear point, respectively. Information on the transmission destination indicating transmission or information on the transmission destination indicating transmission to the rear license plate information generation device 30 is output to the vehicle identification information transmission unit 44.

  Then, as illustrated in FIG. 7D, the vehicle tracking unit 43 recognizes the vehicle “A” and continues tracking even when the vehicle 801 starts. The vehicle tracking unit 43 uses the vehicle identification information “A” and the transmission destination information indicating transmission to the rear license plate information generating device 30 when the vehicle “A” passes the rear point. The data is output to the transmission unit 44.

  Returning to the description of FIG. 3, the vehicle identification information transmission unit 44 outputs the vehicle identification information to the front license plate information generation device 20 or the rear license plate information generation device 30. Specifically, when the vehicle identification information transmitting unit 44 receives the vehicle identification information from the vehicle tracking unit 43, the front number plate information generating device 20 or the rear number is based on the transmission destination information received together with the vehicle identification information. The vehicle identification information is transmitted to the plate information generation device 30.

  The license plate information matching device 50 includes a front and rear part number plate information storage unit 51, a correspondence processing unit 52, a matching unit 53, and a transmission unit 54. The association processing unit 52 corresponds to “front / rear association unit” recited in the claims.

  The front / rear license plate information storage unit 51 stores front license plate information and rear license plate information in association with each other. Specifically, the front license plate information and the rear license plate information are received from the association processing unit 52 described later, and stored in association with each other. For example, as shown in FIG. 8, the front and rear number plate information storage unit 51 stores front number plate information “00-11” and rear number plate information “00-11” in association with each other.

  The correspondence processing unit 52 compares the vehicle identification information stored in the front license plate information storage unit 24 and the rear license plate information storage unit 34, and the front license plate information to which the same vehicle identification information is assigned and Correlate the rear license plate information. Specifically, when a predetermined time (for example, every 6 hours) elapses, the front license plate information storage unit 24 and the rear license plate information storage unit 34 are based on the vehicle identification information associated with the license plate information. The front license plate information and the rear license plate information are read from and stored in the front and rear license plate information storage unit 51 in association with each other. When the association processing unit 52 reads all the information stored in the front license plate information storage unit 24 and the rear license plate information storage unit 34, the front license plate information associated with the verification unit 53 to be described later. And a signal for instructing collation of the rear license plate information.

  The collation unit 53 compares the front license plate information and the rear license plate information associated with each other by the association processing unit 52 to collate whether or not they belong to the same vehicle. Specifically, when receiving the signal from the association processing unit 52, the collation unit 53 reads out the associated front license plate information and rear license plate information from the front and rear license plate information storage unit 51 and compares them. If both are the same, a signal instructing transmission of information relating to “normal vehicle passage” is output to the transmission unit 54, and if both are different, transmission of information relating to “abnormal vehicle passage” is instructed. The signal to be output is output to the transmission unit 54.

  The transmission part 54 transmits the information regarding the presence or absence of abnormality of the passing vehicle to a preset transmission destination (for example, a VICS center or each prefectural traffic control center). Specifically, when a signal is received from the verification unit 53, the information related to “normal vehicle passage” or the information related to “abnormal vehicle passage” is transmitted to a preset transmission destination.

[Processing of License Plate Information Acquisition Device According to Embodiment 1]
Next, various processes of the license plate information acquisition apparatus 10 will be described with reference to FIGS. 9 is a flowchart showing the flow of the front license plate information generation process, FIG. 10 is a flowchart showing the flow of the rear license plate information generation process, and FIG. 11 is a flowchart showing the flow of the vehicle tracking process. FIG. 12 is a flowchart showing the flow of the license plate information association process, and FIG. 13 is a flowchart showing the flow of the license plate information matching process.

(1) Front License Plate Information Generation Processing As shown in FIG. 9, the front license plate information generation device 20 detects a vehicle in the image of the front point by the front vehicle detection processing unit 25 (Yes in step S901). The front number plate recognition unit 26 recognizes the front number plate in the image at the front point (step S902), cuts out an area including the front number plate, and stores the image data in the front number plate image storage unit 23. (Step S903).

  Then, the front license plate information generation device 20 generates front license plate information by the front license plate information reading unit 27 (step S904), and receives vehicle identification information from the vehicle identification information transmission unit 44 (step S905). (Yes), the vehicle identification information and the front license plate information are associated with each other and stored in the front license plate image storage unit 23 (step S906), and the process ends.

(2) Rear License Plate Information Generation Processing As shown in FIG. 10, the rear license plate information generation device 30 detects the vehicle in the rear point image by the rear vehicle detection processing unit 35 (Yes in step S1001), and the rear number. The plate number recognition unit 36 recognizes the rear license plate in the rear point image (step S1002), cuts out the area including the rear number plate, and stores the image data in the rear number plate image storage unit 33 (step S1003). .

  Then, the rear license plate information generation device 30 generates the rear license plate information by the rear license plate information reading unit 37 (step S1004), and receives the vehicle identification information from the vehicle identification information transmission unit 44 (Yes in step S1005). The vehicle identification information and the rear license plate information are associated with each other and stored in the rear license plate image storage unit 33 (step S1006), and the process ends.

(3) Vehicle Tracking Process As shown in FIG. 11, when the vehicle tracking device 40 detects a vehicle in the image of the monitoring range by the vehicle tracking unit 43 (step S1101), the vehicle tracking device 40 tracks the vehicle by providing vehicle identification information. (Step S1102). When the vehicle being tracked enters the forward point (step S1103), the vehicle tracking device 40 transmits the vehicle identification information given to the vehicle to the front license plate information reading unit 27 by the vehicle identification information transmitting unit 44. (Step S1104). Then, the vehicle tracking device 40 continues to track the vehicle, and when the vehicle enters the rear point (step S1105), the vehicle identification information given to the vehicle is read by the rear license plate information by the vehicle identification information transmitting unit 44. It transmits to the part 37 (step S1106), and complete | finishes a process.

(4) Correspondence processing between front license plate information and rear license plate As shown in FIG. 12, the license plate information collation apparatus 50, when a predetermined time has elapsed (Yes in step S1201), causes the correspondence processing unit 52 to One front license plate information is acquired from the license plate information storage unit 24 (step S1202), and the same from the rear license plate information storage unit 34 based on the vehicle identification information associated with the front license plate information. The rear license plate information associated with the vehicle identification information is acquired (step S1203), and both are associated with each other and stored in the front and rear license plate information storage unit 51 (step S1204). If the license plate information matching device 50 has not acquired all the front license plate information (No at step S1205), the license plate information collating device 50 continues the same operation until all the front license plate information is acquired. When the front license plate information is acquired (Yes at step S1205), the processing by the association processing unit 52 is terminated.

(5) License Plate Information Collation Processing As shown in FIG. 13, when the collation unit 53 receives a signal from the association processing unit 52 (step S1301), the license plate information collation device 50 is associated with the front number. The plate information and the rear license plate information are acquired from the front and rear license plate information storage unit 51 by the verification unit 53, and both are verified (step S1302). When the license plate information matching device 50 matches the two (Yes in step S1303), the transmission unit 54 transmits information related to “passing through the normal vehicle” to a preset transmission destination (step S1304). ) If they are different (No at Step S1303), the transmission unit 54 transmits information related to “abnormal vehicle passage” to a preset transmission destination (Step S1305). Then, the license plate information collating apparatus 50 determines that all collations for the associated front license plate information and rear license plate information stored in the front and rear license plate information storage unit 51 have not been completed (No in step S1306). ), The same operation is continued until all the collations are completed, and when all the collations are completed (Yes in step S1306), the processes by the collation unit 53 and the transmission unit 54 are terminated.

[Effect of Example 1]
As described above, according to the first embodiment, a vehicle that is about to pass through the front point is detected, and the vehicle is uniquely identified until the detected vehicle passes from the front point to the rear point. The state in which the vehicle identification information is given to the vehicle is maintained, the vehicle is tracked, the vehicle identification information given to the vehicle from which the front license plate information is obtained is obtained, and the vehicle identification information obtained before the vehicle is obtained. The part number plate information and the vehicle identification information are stored in association with each other, the vehicle identification information given to the vehicle from which the rear part number plate information is obtained is obtained, and the rear number plate information and the vehicle obtained from the vehicle are obtained. The identification number is held in association with each other, the vehicle identification information held is compared, and the front license plate information and the rear number assigned the same vehicle identification information. Since associates plate information, without being affected by the movements of the vehicle, it is possible to associate with the integrity of the front and rear license plate information as the same vehicle. In other words, even when the vehicle pauses between the front and rear points, re-starts and enters the rear point, the front and rear license plate information is consistently associated with the same vehicle. In addition, even when another vehicle overtakes a temporarily stopped vehicle, it is possible to associate the front and rear license plate information with the same vehicle in a consistent manner. Even when the vehicle changes lanes, it is possible to associate the front and rear license plate information with the same vehicle with consistency.

  In addition, according to the first embodiment, by processing an image obtained by imaging a region including the front point and the rear point, a vehicle that attempts to pass the front point is detected, and vehicle identification information is transmitted to the vehicle. Since the vehicle is tracked while maintaining the imparted state, it is possible to track the vehicle even in a situation where a plurality of vehicles are dense, as compared with a method using electromagnetic waves.

  Further, according to the first embodiment, the fisheye lens camera connected to the vehicle tracking device is installed on the pillar located between the front point and the rear point together with the front camera and the rear camera. In addition to detecting, the vehicle is tracked while maintaining the state where the vehicle identification information is given to the vehicle. Therefore, compared to the method of installing an imaging unit that outputs image data to the vehicle tracking device at a remote position, Such costs can be reduced.

  Also, according to the first embodiment, the front license plate information and the rear license plate information associated by the license plate information verification device are compared to verify whether they are of the same vehicle. It is possible to improve the accuracy of finding the. That is, since the license plate information acquisition device collates the front license plate information and the rear license plate information in a consistent state, it is possible to increase the accuracy of finding a violation vehicle.

  In the first embodiment, the method of associating the vehicle front license plate information and the rear license plate information in one lane has been described. In the second embodiment, the vehicle front license plate information and the rear license plate in two lanes are described. A method for associating information will be described.

  First, an overview of the license plate information acquisition apparatus according to the second embodiment will be described with reference to FIG. FIG. 14 is a diagram illustrating an overview of the license plate information acquisition apparatus according to the second embodiment.

  As shown in the figure, the license plate information acquisition device 60 is fixed to the pillar 1 standing on the side of the rear roadway in the same manner as in the first embodiment, and includes a first lane front camera 71 and a first lane rear part. The camera 81 and the fisheye lens camera 91 are fixed to a portion where the pillar 1 protrudes upward in the roadway. The second lane front camera 101 and the second lane rear camera 111 are installed on the pillar 5 standing on the side of the roadway in front, and the license plate information acquisition device 60 and the first lane front camera 71 are installed. The first lane rear camera 81, the fisheye lens camera 91, the second lane front camera 101, and the second lane rear camera 111 are connected by a dedicated cable.

  The first lane front camera 71 always images the first lane front point 6 which is the imaging area of the first lane front camera 71, outputs the image data to the license plate information acquisition device 60, and Similarly, the lane rear camera 81 always images the first lane rear point 7 which is the imaging area of the first lane rear camera 81 and outputs the image data to the license plate information acquisition device 60. The second lane front camera 101 always images the second lane front point 8 which is the imaging area of the second lane front camera 101, and outputs the image data to the license plate information acquisition device 60. Similarly, the second lane rear camera 111 constantly images the second lane rear point 9 which is the imaging area of the second lane rear camera 111 and outputs the image data to the license plate information acquisition device 60. Further, the fisheye lens camera 91 always images a wide area including the first lane front point 6, the first lane rear point 7, the second lane front point 8, and the second lane rear point 9, and similarly, the image data Is output to the license plate information acquisition device 60.

[Configuration of License Plate Information Acquisition Device According to Example 2]
Next, the configuration of the license plate information acquisition apparatus 60 shown in FIG. 14 will be described with reference to FIG. FIG. 15 is a block diagram showing the configuration of the license plate information acquisition device 60. As shown in the figure, the license plate information acquisition device 60 includes a first lane front license plate information generation device 70, a first lane rear license plate information generation device 80, a vehicle tracking device 90, and a second lane. It consists of a front license plate information generation device 100, a second lane rear license plate information generation device 110, and a license plate information collation device 120.

  The first lane front number plate information generating device 70 includes a first lane front image temporary storage unit 72, a first lane front number plate image storage unit 73, and a first lane front number plate information storage unit. 74, a first lane front vehicle detection processing unit 75, a first lane front license plate recognition unit 76, and a first lane front license plate information reading unit 77, and a first lane front camera 71, Connected. The first lane front license plate information storage unit 74 corresponds to “front information holding means” described in the claims.

  The first lane rear license plate information generator 80 includes a first lane rear image temporary storage unit 82, a first lane rear license plate image storage unit 83, a first lane rear license plate information storage unit 84, A one-lane rear vehicle detection processing unit 85, a first lane rear number plate recognition unit 86, and a first lane rear number plate information reading unit 87 are connected to the first lane rear camera 81. The first lane rear license plate information storage unit 84 corresponds to the “rear information holding unit” recited in the claims.

  The vehicle tracking device 90 includes a monitoring image storage unit 92, a vehicle tracking unit 93, and a vehicle identification information transmission unit 94, and is connected to the fisheye lens camera 91. The vehicle tracking unit 93 corresponds to “vehicle tracking means” described in the claims.

  The second lane front license plate information generating device 100 includes a second lane front image temporary storage unit 102, a second lane front license plate image storage unit 103, and a second lane front license plate information storage unit. 104, a second lane front vehicle detection processing unit 105, a second lane front license plate recognition unit 106, and a second lane front license plate information reading unit 107, and a second lane front camera 101, Connected. The second lane front license plate information storage unit 104 corresponds to “front information holding means” described in the claims.

  The second lane rear license plate information generator 110 includes a second lane rear image temporary storage unit 112, a second lane rear license plate image storage unit 113, a second lane rear license plate information storage unit 114, A two-lane rear vehicle detection processing unit 115, a second lane rear license plate recognition unit 116, and a second lane rear license plate information reading unit 117 are provided, and are connected to the second lane rear camera 111. The second lane rear license plate information storage unit 114 corresponds to “rear information holding means” described in the claims.

  The license plate information collation apparatus 120 includes a front / rear number plate information storage unit 121, a correspondence processing unit 122, a collation unit 123, and a transmission unit 124. The association processing unit 122 corresponds to “front / rear association means” recited in the claims.

  It should be noted that the first lane front image temporary storage unit 72 and the second lane front image temporary storage unit 102 in the first lane front license plate information generation device 70 and the second lane front license plate information generation device 100, and A first lane front license plate image storage unit 73 and a second lane front license plate image storage unit 103; a first lane front license plate information storage unit 74; a second lane front license plate information storage unit 104; A first lane front vehicle detection processing unit 75 and a second lane front vehicle detection processing unit 105, a first lane front number plate recognition unit 76, a second lane front number plate recognition unit 106, and a first lane front The license plate information reading unit 77 and the second lane front number plate information reading unit 107 are respectively the front part number according to the first embodiment. Front image temporary storage unit 22, front license plate image storage unit 23, front license plate information storage unit 24, front vehicle detection processing unit 25, and front license plate recognition unit in plate information generating device 20 26 and the same processing as that performed by the front license plate information reading unit 27, and the description thereof will be omitted.

  The first lane rear license plate information generator 80, the second lane rear license plate information generator 110, the first lane rear image temporary storage unit 82, the second lane rear image temporary storage unit 112, and the first lane rear number. Plate image storage unit 83 and second lane rear license plate image storage unit 113, first lane rear license plate information storage unit 84, second lane rear license plate information storage unit 114, and first lane rear vehicle detection processing unit 85 The second lane rear vehicle detection processing unit 115, the first lane rear license plate recognition unit 86, the second lane rear license plate recognition unit 116, the first lane rear license plate information reading unit 87, and the second lane rear license plate. The information reading unit 117 is a rear number according to the first embodiment. Rear image temporary storage unit 32, rear license plate image storage unit 33, rear license plate information storage unit 34, rear vehicle detection processing unit 35, rear license plate recognition unit 36, and rear number in plate information generating device 30 Since the same processing as that of the plate information reading unit 37 is performed, the description thereof is omitted.

  Further, the monitoring image storage unit 92 in the vehicle tracking device 90 performs the same processing as the monitoring image storage unit in the vehicle tracking device 40 according to the first embodiment, and thus the description thereof is omitted, and the front and rear part numbers in the license plate information matching device 120 are omitted. The plate information storage unit 121, the verification unit 123, and the transmission unit 124 are respectively the front and rear license plate information storage unit 51, the verification unit 53, and the transmission unit 54 in the license plate information verification device 50 according to the first embodiment. Since the same processing is performed, the description is omitted. Therefore, only the vehicle tracking unit 93, the vehicle identification information transmission unit 94, and the association processing unit 122 will be described below.

  The vehicle tracking unit 93 detects a vehicle that is about to pass through the first lane forward point or the second lane forward point, and the detected vehicle moves from the first lane forward point or the second lane forward point to the first lane backward point or The vehicle is tracked while maintaining the state in which the vehicle identification information for uniquely identifying the vehicle is given to the vehicle until the vehicle passes the second lane point.

  Specifically, the vehicle tracking unit 93 reads image data of a wide area from the monitoring image storage unit 92, and when the vehicle is detected in the image, the vehicle tracking unit 93 tracks the vehicle while giving vehicle identification information to the vehicle. The vehicle tracking unit 93 also includes vehicle identification information given to the vehicle when the vehicle passes through the first lane front point, the second lane front point, the first lane rear point, or the second lane rear point, and The vehicle identification information is transmitted to the first lane front license plate information generation device 70, transmitted to the first lane rear license plate information generation device 80, or transmitted to the second lane front license plate information generation device 100. Or the transmission destination information indicating whether to transmit to the second lane rear license plate information generation device 110 is output to the vehicle identification information transmission unit 94.

  The vehicle identification information transmission unit 94 transmits vehicle identification information to the first lane front license plate information generation device 70, the first lane rear license plate information generation device 80, the second lane front license plate information generation device 100, or the second lane. The information is output to the rear license plate information generation device 110.

  Specifically, the vehicle identification information transmission unit 94 receives a vehicle from the vehicle tracking unit 93 when the vehicle passes the first lane front point, the second lane front point, the first lane rear point, or the second lane rear point. When the identification information is received, the first lane front license plate information generation device 70, the first lane rear license plate information generation device 80, and the second lane front license plate based on the destination information received together with the vehicle identification information. The vehicle identification information is transmitted to the information generation device 100 or the second lane rear license plate information generation device 110.

  The correspondence processing unit 122 includes a first lane front license plate information storage unit 74, a first lane rear license plate information storage unit 84, a second lane front license plate information storage unit 104, and a second lane rear license plate information storage. The vehicle identification information stored in the unit 114 is compared, and the front license plate information and the rear license plate information to which the same vehicle identification information is assigned are associated.

  Specifically, when a predetermined time (for example, every 6 hours) elapses, the first lane front license plate information storage unit 74, the first lane rear part, based on the vehicle identification information associated with the license plate information. The front license plate information and the rear license plate information are read from the license plate information storage section 84, the second lane front license plate information storage section 104, and the second lane rear license plate information storage section 114, and the front and rear sections are associated with each other. It is stored in the license plate information storage unit 121. The processing of the association processing unit 122 will be described later with reference to FIG.

[Processing of License Plate Information Acquisition Device According to Embodiment 2]
Next, processing of the license plate information acquisition device 60 will be described with reference to FIG. FIG. 16 is a flowchart illustrating the flow of the license plate information association processing according to the second embodiment.

  As shown in FIG. 16, the license plate information matching device 120, when a predetermined time has elapsed (Yes in step S1601), causes the corresponding processing unit 122 to change the first lane front from the first lane front license plate information storage unit 74. Part number plate information is acquired (step S1602), and the same vehicle identification information is handled from the first lane rear number plate information storage unit 84 based on the vehicle identification information associated with the first lane front number plate information. The attached first lane rear license plate information is searched (step S1603).

  When the license plate information collating device 120 finds the first lane rear license plate information associated with the same vehicle identification information by the association processing unit 122 (Yes in step S1604), the license plate information collating device 120 associates the two with each other. The license plate information is stored in the license plate information storage unit 121 (step S1605), and if it is not found (No in step S1604), the second lane rear license plate information storage unit 114 is searched and the second license plate information associated with the same vehicle identification information is searched. Two-lane rear license plate information is found, and both are associated and stored in the front and rear license plate information storage unit 121 (step S1606).

  If the license plate information collating device 120 has not acquired all the first lane front license plate information (No in step S1607), the license plate information collating device 120 is associated until it acquires all the first lane front license plate information. If the same operation is continued by the processing unit 122 and all the first lane front number plate information is acquired (Yes in step S1607), the corresponding processing unit 122 similarly similarly uses the second lane front number plate information storage unit 104. One second lane front license plate information is acquired (step S1608), and from the second lane rear license plate information storage unit 114 based on the vehicle identification information associated with the second lane front license plate information. The second lane rear license plate information associated with the same vehicle identification information is searched (step by step). Flop S1609).

  Then, when the second lane rear license plate information associated with the same vehicle identification information is found (Yes at step S1610), the license plate information matching device 120 associates the two with the corresponding processing unit 122, and then Stored in the part number plate information storage unit 121 (step S1611), and if not found (No in step S1610), the first lane rear part number plate information storage unit 84 is searched, and the number corresponding to the same vehicle identification information is searched. One-lane rear license plate information is found, and both are associated and stored in the front and rear license plate information storage unit 121 (step S1612).

  If the license plate information collation device 120 has not acquired all the second lane front license plate information (No in step S1613), the license plate information collating device 120 is associated until it acquires all the first lane front license plate information. If the same operation is continued by the processing unit 122 and all the second lane front license plate information is acquired (Yes at step S1613), the processing by the association processing unit 122 is terminated.

  In the second embodiment, the license plate information acquisition device in two lanes has been described. However, in a plurality of lanes of two or more lanes, a front camera and a rear camera are installed for each lane, and front license plate information for each lane is provided. If the rear license plate information is generated, it is possible to associate them with consistency.

[Effect of Example 2]
As described above, according to the second embodiment, the front license plate information and the rear license plate information are acquired for each lane in a plurality of lanes, and the vehicle is about to pass the front point for each lane. The vehicle is tracked while maintaining the state in which the vehicle identification information is given to the vehicle until the detected vehicle passes through the rear point of any lane from the front point. Plate information and vehicle identification information in association with each other, comparing vehicle identification information of the same lane, if there is front license plate information and rear license plate information to which the same vehicle identification information is given, The front license plate information and the rear license plate information are associated with each other, and the front license plate information is assigned the same vehicle identification information. In the case where there is no rear license plate information, the vehicle identification information of different lanes is compared, and the front license plate information and the rear license plate information to which the same vehicle identification information is assigned are associated. Even if the vehicle changes lanes, the front and rear license plate information can be consistently associated with the same vehicle, and compared to a method that collectively holds information generated in multiple lanes. Thus, the processing speed for associating the front license plate information and the rear license plate information can be increased by the amount of time required for the search.

  By the way, although the license plate information acquisition apparatus which concerns on Example 1 or 2 was demonstrated until now, this invention may be implemented with a various different form other than an above-described Example. Therefore, in the following, as license plate information acquisition apparatuses according to the third embodiment, different embodiments will be described by dividing them into (1) to (7).

(1) Matching Condition In the above-described first or second embodiment, the association processing unit of the license plate information acquisition device is based on the front license plate information and the rear part only based on the vehicle identification information associated with the license plate information. Although the case where the license plate information is associated with consistency has been described, the present invention is not limited to this, and consistency is determined not only by the vehicle identification information but also by vehicle color information and shape information. You may do it.

  For example, in the license plate information acquisition apparatus 10 according to the first embodiment, the vehicle tracking unit 43 includes the vehicle color information and shape information acquired from the image data in addition to the vehicle identification information given to the vehicle. 44. By doing so, for example, the front license plate information storage unit 24 stores the front license plate information in association with vehicle identification information, vehicle color information, and vehicle shape information. Then, the association processing unit 52 associates the front license plate information and the rear license plate information with consistency based on the vehicle identification information, the vehicle color information, and the vehicle shape information. That is, the association processing unit 52 associates the front license plate information and the rear license plate information with consistency on condition that the vehicle identification information, the vehicle color information, and the vehicle shape information are all the same. May be performed.

  Thus, the color information and shape information of the vehicle from which the front license plate information was acquired, and the color information and shape information of the vehicle from which the rear license plate information was acquired, respectively, the color information and shape information, Front number plate information and rear number assigned with the same vehicle identification information, color information and shape information by comparing the vehicle identification information, color information and shape information in correspondence with the license plate information and vehicle identification information Since the plate information is associated with each other, there are a plurality of criteria for determining consistency, and the reliability of consistency can be increased.

(2) Time information In the above-described first or second embodiment, the association processing unit of the license plate information acquisition apparatus is configured based on the front license plate information and the rear part based only on the vehicle identification information associated with the license plate information. The case where the license plate information is associated with the consistency has been described, but the present invention is not limited to this, and in addition to the vehicle identification information, the front portion is information on the time when the vehicle passes the front point. Consistency may be determined based on time information or rear time information that is information on the time of passing through a rear point.

  For example, in the license plate information acquisition device 10 according to the first embodiment, if the vehicle tracking device 40 cannot track the vehicle for some reason, the front license plate information storage unit 24 or the rear license plate information storage unit 34 Stores front license plate information and rear license plate information not associated with vehicle identification information. Therefore, the vehicle tracking device 40 transmits the front time information and the rear time information to the front license plate information generation device 20 and the rear license plate information generation device 30, respectively, in addition to the vehicle identification information, and stores the front license plate information. In addition to the vehicle identification information, the front license plate information associated with the front time information and the rear license plate information associated with the rear time information are stored in the unit 24 and the rear license plate information storage unit 34. The

  And the corresponding | compatible process part 52 judges consistency with respect to the front number plate information and rear part number plate information which are not matched with vehicle identification information based on front time information and rear part time information ( For example, consistency is determined based on the fact that the difference between the front time information and the rear time information is within a predetermined time), and the two are associated with each other and stored in the front / rear license plate information storage unit 51.

  In this manner, time information indicating the time when the front license plate information is acquired and time information indicating the time when the rear license plate information is acquired are respectively acquired and associated with the license plate information and the vehicle identification information. When the vehicle identification information and the time information are compared, and the front license plate information and the rear license plate information to which the same vehicle identification information or adjacent time information is assigned are associated with each other, so that the vehicle cannot be tracked. However, it is possible to associate with consistency based on the time information.

(3) Installation position In Example 1 or 2 described above, the license plate information acquisition device has been described as being fixedly installed on one pillar, but the present invention is not limited to this, For example, as shown in FIG. 17, in the license plate information acquisition apparatus 10 according to the first embodiment, a wide area that includes the front point and the rear point is imaged, and the image data is output to the vehicle tracking unit 42. An imaging unit 130 that replaces the fisheye lens camera 41 may be provided, and the imaging unit 130 may be fixed to the pillar 170 located downstream of the pillar 1. The imaging unit 130 does not need to be equipped with a fisheye lens. For example, the imaging unit 130 is equipped with a wide-angle lens or the like to image a wide area and outputs the image data to the vehicle tracking unit 43.

  In this way, the front camera that images the front license plate of the vehicle passing through the front point and the rear license plate of the vehicle passing through the rear point are arranged on the column located upstream or downstream from the front point and the rear point. Since it is installed separately from the rear camera that captures the image and detects the vehicle that is about to pass through the front point and tracks the vehicle while maintaining the state in which the vehicle identification information is given to the vehicle, for example, the monitoring range is imaged. Therefore, compared with the method in which the vehicle tracking means using the fisheye lens is installed on the same column, the processing speed of the vehicle tracking can be increased by the amount of time required for correcting the image captured by the fisheye lens. It becomes.

(4) Vehicle Tracking In the first or second embodiment described above, the license plate information acquisition device senses a vehicle by imaging a wide area, which is an area including the front point and the rear point, and processing the image data. However, the present invention is not limited to this. For example, an electromagnetic wave such as a millimeter wave is transmitted to a wide area, and the vehicle is detected by capturing the reflected wave. You may make it track.

  In this way, by processing the reflected wave returned by the electromagnetic wave transmitted toward the area including the front point and the rear point, the vehicle that is about to pass the front point is detected, and the vehicle identification information is stored in the vehicle. Since the vehicle is tracked while maintaining the state given to the vehicle, it is possible to track the vehicle even in situations where it is difficult to recognize the image (for example, at night) compared to the method using image recognition technology. Become.

(5) License plate information storage unit In the second embodiment, the license plate information acquisition device 60 has described the case where the front license plate information and the rear license plate information are stored separately for each lane. For example, the first lane front number plate information storage unit 74 and the second lane front number plate information storage unit 104 are integrated, and the first lane rear number plate is not limited thereto. Provide a rear storage unit that integrates the information storage unit 84 and the second lane rear license plate information storage unit 114 so that the front license plate information and the rear license plate information are held together without being divided into lanes. Also good. In this case, the association processing unit 122 acquires the front license plate information from the front storage unit without distinguishing between lanes, and searches the rear storage unit, thereby matching the same vehicle identification information. Search the rear license plate information and associate them.

(6) System Configuration, etc. The processing procedures, control procedures, specific names, information including various data and parameters shown in the above documents and drawings can be arbitrarily changed unless otherwise specified. For example, in the processing procedure shown in FIG. 16, the case where the first lane front license plate information is sequentially acquired from the first lane front license plate information storage unit has been described, but the present invention is not limited to this. For example, the second lane front license plate information may be sequentially acquired from the second lane front license plate information storage unit. Further, for example, the vehicle identification information shown in FIG. 1 is written in alphabets, but the present invention is not limited to this. For example, at least a license plate information acquisition device such as a number can uniquely identify a vehicle. If it is.

  Each component of the illustrated devices (the license plate information acquisition device 10 and the license plate information acquisition device 60) is functionally conceptual and does not necessarily have to be physically configured as illustrated. That is, the specific form of distribution / integration of each device is not limited to the illustrated one. For example, the vehicle tracking unit 43 and the vehicle identification information transmission unit 44 are integrated, or the collation unit 53 and the transmission unit 54 are integrated. For example, all or a part thereof can be configured to be functionally or physically distributed / integrated in an arbitrary unit according to various loads or usage conditions. Further, all or any part of each processing function performed in each device may be realized by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware by wired logic.

(7) License plate information acquisition program In the above-described first or second embodiment, the case where various processes are realized by hardware logic has been described. However, the present invention is not limited to this and is prepared in advance. The program may be realized by executing the program on a computer. Therefore, in the following, an example of a computer that executes a license plate information acquisition program having the same function as the license plate information acquisition apparatus 10 shown in the first embodiment will be described with reference to FIG. FIG. 18 is a diagram illustrating a computer that executes a license plate information acquisition program.

  As shown in the figure, a computer 130 serving as a license plate information acquisition device has a front camera 131, a rear camera 132, a fisheye lens camera 133, a CPU 134, a ROM 135, an HDD 136, a RAM 137, and an output antenna 138 connected by a bus 139 or the like. Composed.

  In the ROM 135, a license plate information acquisition program that exhibits the same function as the license plate information acquisition device 10 shown in the first embodiment, that is, as shown in FIG. Part number plate recognition program 135b, front part number plate information reading program 135c, vehicle tracking program 135d, vehicle identification information transmission program 135e, rear part vehicle detection processing program 135f, rear part number plate recognition program 135g, rear part number A plate information reading program 135h, a correspondence processing program 135i, a collation program 135j, and a transmission program 135k are stored in advance. In addition, about these programs 135a-135k, you may integrate or disperse | distribute suitably like each component of the license plate information acquisition apparatus 10 shown in FIG.

  And CPU134 reads these programs 135a-135k from ROM135, and as shown in FIG. 18, each program 135a-135k is the front vehicle detection process 134a, the front license plate recognition process 134b. Front license plate information reading process 134c, vehicle tracking process 134d, vehicle identification information transmission process 134e, rear vehicle detection processing process 134f, rear license plate recognition process 134g, rear license plate information reading process 134h, association processing process 134i, It functions as a collation process 134j and a transmission process 134k. Each of the processes 134a to 134k includes the front vehicle detection processing unit 25, the front license plate recognition unit 26, the front license plate information reading unit 27, the vehicle tracking unit 43, and the vehicle identification information transmission unit 44 illustrated in FIG. , Corresponding to the rear vehicle detection processing unit 35, the rear license plate recognition unit 36, the rear license plate information reading unit 37, the association processing unit 52, the verification unit 53, and the transmission unit 54.

  Further, as shown in FIG. 18, the HDD 136 has a front image data 136a, a front license plate image data 136b, a front license plate information table 136c, monitoring image data 136d, a rear image data 136e, A rear license plate image data 136f, a rear license plate information table 136g, and a front and rear license plate information table 136h are provided. The front image data 136a, the front license plate image data 136b, the front license plate information table 136c, the monitoring image data 136d, the rear image data 136e, the rear license plate image data 136f, the rear license plate information table 136g, and the front and rear portions The license plate information table 136h includes a front image temporary storage unit 22, a front license plate image storage unit 23, a front license plate information storage unit 24, a monitoring image storage unit 42, and a rear image shown in FIG. These correspond to the temporary storage unit 32, the rear license plate image storage unit 33, the rear license plate information storage unit 34, and the front and rear license plate information storage unit 51, respectively.

  The CPU 134 then controls the front image data 136a, the front license plate image data 136b, the front license plate information table 136c, the monitoring image data 136d, the rear image data 136e, the rear license plate image data 136f, and the rear license plate information table 136g. The front image data 137a, the front license plate image data 137b, the front license plate information table 137c, the monitoring image data 137d, the rear image data 137e, the rear license plate image data 137f, the rear The license plate information table 137g and the front and rear license plate information table 137h are read out and stored in the RAM 137, and the front image data stored in the RAM 137 37a, front license plate image data 137b, front license plate information table 137c, monitoring image data 137d, rear image data 137e, rear license plate image data 137f, rear license plate information table 137g and front and rear license plate information table 137h Based on the above, vehicle tracking, front license plate information generation, etc. are executed.

  Note that the above-described programs 135a to 135k are not necessarily stored in the ROM 135 from the beginning. For example, a flexible disk (FD), a CD-ROM, an MO disk, a DVD disk, an optical disk inserted into the computer 130, and the like. Via a “portable physical medium” such as a magnetic disk or an IC card, or a “fixed physical medium” such as an HDD provided inside or outside the computer 130, or via a public line, the Internet, a LAN, a WAN, etc. Each program may be stored in “another computer (or server)” connected to the computer 130, and the computer 130 may read and execute each program therefrom.

  As described above, the license plate information acquisition device, the license plate information acquisition method, and the license plate information acquisition program according to the present invention are configured so that the front license plate information displayed on the front license plate of the vehicle passing through the front point is displayed. It is useful for acquiring the rear license plate information displayed on the rear license plate of the vehicle passing through the rear point and associating the front license plate information and the rear license plate information. It is suitable for matching the license plate information of the front part and the rear part of the same vehicle with consistency without depending on movement.

  The present invention relates to a license plate information acquisition apparatus and a license plate information acquisition method.

  Conventionally, the number plates of the front and rear vehicles in motion are imaged, and the number plate information read on the front and rear number plates is read from the image by character recognition. A technique for associating plate information with the same vehicle has been devised.

  For example, Patent Document 1 discloses a technique described below. That is, as shown in FIG. 19A, when the vehicle 1901 enters the front imaging point 1902, the front license plate reading device 1903 reads the front part read by imaging the front license plate of the vehicle 1901. The license plate information (for example, serial number “12-34”, etc.) is stored in the front license plate information storage unit 1905 of the information processing apparatus 1904 in association with the time T1 when the front license plate information is read. The sensor 1906 measures the speed V (m / sec) of the vehicle and the total length l (m) of the vehicle.

  Here, the information processing apparatus 1904 sets the rear imaging point 1907 from V (m / sec), l (m), and a known distance L (m) from the front imaging point 1902 to the rear imaging point 1907. An expected time T2 at which the vehicle enters is obtained.

  Then, as shown in FIG. 19B, when the vehicle 1901 enters the rear imaging point 1907, the rear license plate reader 1908 similarly reads the license plate read by imaging the rear license plate of the vehicle 1901. The information is stored in the rear license plate information storage unit 1909 of the information processing apparatus 1904 in association with the time T3 when the license plate information is read.

  Then, as shown in FIG. 19C, the information processing apparatus 1904, when the time T3 is within the range of the time T2 ± ΔT obtained by adding or subtracting the error ΔT to the expected time T2, reads before the time T1. The part number plate information and the rear part number plate information read at time T3 are associated with each other as the same vehicle, and stored in the associated number plate information storage unit 1910 that the self part number is associated with. The information processing apparatus 1904 determines whether or not the vehicle is a violation vehicle by collating the associated front and rear license plate information, and warns on the spot or warns at a later date. Realized.

JP 2003-228793 A

  By the way, the above-described conventional technology has a problem that the front license plate information and the rear license plate information cannot be associated with each other depending on the movement of the vehicle. For example, when the vehicle pauses in the section between the front imaging point and the rear imaging point, re-starts and enters the rear imaging point, the estimated time of arrival at the rear imaging point of the vehicle Therefore, the front license plate information cannot be associated with the rear license plate information with consistency. In addition, if another vehicle overtakes a temporarily stopped vehicle and enters the rear imaging point at a time within the range where the error is adjusted in the estimated time of arrival at the rear imaging point of the vehicle, the front number of the overtaken vehicle Since the plate information and the rear license plate information of the overtaken vehicle are associated with each other, an incorrect association is performed and the association cannot be performed with consistency. Furthermore, application to multiple lanes is not always consistent because the errors caused by the vehicle changing lanes cannot be determined unambiguously, and multiple front and rear imaging points must be associated with consideration of vehicle lane changes. Could not be associated with sex.

  Accordingly, the present invention has been made to solve the above-described problems of the prior art, and the front and rear license plate information is consistent with those of the same vehicle without being influenced by the movement of the vehicle. It is an object to provide a license plate information acquisition device and a license plate information acquisition method that can be associated with each other.

  In order to solve the above-described problems and achieve the object, the invention according to claim 1 acquires the front license plate information displayed on the front license plate of the vehicle passing through the front point, and the rear point. A license plate information acquisition device that acquires rear license plate information displayed on a rear license plate of a passing vehicle and associates the front license plate information and the rear license plate information with each other, and tries to pass the front point The vehicle is detected and the vehicle is tracked while maintaining the state in which the vehicle identification information for uniquely identifying the vehicle is given to the vehicle until the detected vehicle passes from the front point to the rear point. Vehicle tracking means, and the vehicle tracking means for the vehicle from which the front license plate information is acquired Front information holding means for acquiring vehicle identification information that is acquired and associating and holding front license plate information and vehicle identification information acquired from the vehicle, and a vehicle from which the rear license plate information is acquired. A rear information holding means for acquiring the vehicle identification information given by the vehicle tracking means and holding the rear license plate information and the vehicle identification information acquired from the vehicle in association with each other, the front information holding means, The vehicle identification information held in the rear information holding means is compared, and the front number plate information to which the same vehicle identification information is assigned and the front rear correspondence means for associating the rear number plate information are provided. It is characterized by.

  Further, in the invention according to claim 2, in the above invention, the vehicle tracking means tries to pass the front point by processing an image obtained by imaging an area including the front point and the rear point. And detecting the vehicle to be tracked while keeping the state where the vehicle identification information is given to the vehicle.

  Further, in the invention according to claim 3, in the above invention, the vehicle tracking unit processes the reflected wave returned by the electromagnetic wave transmitted toward the region including the front point and the rear point, While detecting the vehicle which is going to pass the front point, the vehicle is tracked while maintaining the state where the vehicle identification information is given to the vehicle.

  The invention according to claim 4 is the above invention, wherein the front license plate information and the rear license plate information are acquired for each lane in a plurality of lanes, and the vehicle tracking means A state in which a vehicle that tries to pass the front point is detected for each lane, and the vehicle identification information is given to the vehicle until the detected vehicle passes a rear point of any lane from the front point. The front information holding means and the rear information holding means hold the license plate information and the vehicle identification information in association with each lane, and the front / rear association means Front number play in which the same vehicle identification information is given by comparing the vehicle identification information of the same lane held in the front information holding means and the rear information holding means When there is information and rear license plate information, the front license plate information and rear license plate information are associated with each other, and there is no front license plate information and rear license plate information to which the same vehicle identification information is given. For comparing the vehicle identification information of the different lanes held in the front information holding means and the rear information holding means, the front license plate information and the rear license plate information to which the same vehicle identification information is given are It is characterized by associating.

  Moreover, the invention which concerns on Claim 5 is displayed on the rear number plate of the vehicle which passes the back point while acquiring the front number plate information currently displayed on the front number plate of the vehicle which passes the front point. A license plate information acquisition method for acquiring the rear license plate information and associating the front license plate information and the rear license plate information, detecting a vehicle that is about to pass through the front point, and detecting the vehicle A vehicle tracking step for tracking the vehicle while maintaining a state in which vehicle identification information for uniquely identifying the vehicle is given to the vehicle from the front point to the rear point, and the front number plate Vehicle identification information given by the vehicle tracking step to the vehicle from which the information is acquired, A front information holding step for holding the front license plate information and vehicle identification information acquired from both in association with each other, and a vehicle that is given by the vehicle tracking step to the vehicle from which the rear license plate information is acquired. A rear information holding step of acquiring identification information and associating and holding rear license plate information and vehicle identification information acquired from the vehicle, and vehicle identification information held in the front information holding step and rear information holding step And a front / rear association step of associating the front license plate information and the rear license plate information to which the same vehicle identification information is assigned.

  According to the first and fifth aspects of the present invention, a vehicle for detecting a vehicle that is about to pass through the front point and uniquely identifying the vehicle until the detected vehicle passes from the front point to the rear point. The state where the identification information is given to the vehicle is held, the vehicle identification information given to the vehicle from which the front number plate information is obtained, the front number plate information and the vehicle obtained from the vehicle The identification information is held in association with each other, the vehicle identification information given to the vehicle for which the rear license plate information is acquired is acquired, and the rear license plate information and the vehicle identification information acquired from the vehicle are associated with each other. Holding and comparing the vehicle identification information and associating the front license plate information and the rear license plate information to which the same vehicle identification information is assigned. Without being affected by the movements of the vehicle, it is possible to associate with the integrity of the front and rear license plate information as the same vehicle.

  According to the invention of claim 2, by processing an image obtained by imaging a region including the front point and the rear point, a vehicle that is about to pass the front point is detected, and the vehicle identification information is Since the vehicle is tracked while maintaining the state given to the vehicle, it is possible to track the vehicle even in a situation where a plurality of vehicles are dense, as compared with a method using electromagnetic waves.

  According to the invention of claim 3, while detecting the vehicle which is going to pass the front point by processing the reflected wave returned by the electromagnetic wave transmitted toward the region including the front point and the rear point. Since the vehicle is tracked while maintaining the state in which the vehicle identification information is given to the vehicle, the vehicle can be used even in situations where it is difficult to recognize an image (for example, at night) as compared with a method using image recognition technology. Can be tracked.

  According to the invention of claim 4, the front license plate information and the rear license plate information are acquired for each lane in a plurality of lanes, and a vehicle that is about to pass through the front point for each lane. Until the detected vehicle passes through the rear point of any lane from the front point, the vehicle is tracked while maintaining the state where the vehicle identification information is given to the vehicle, and the license plate information for each lane And vehicle identification information in association with each other, comparing vehicle identification information of the same lane, and if there is front license plate information and rear license plate information to which the same vehicle identification information is assigned, Number plate information and rear number plate information are associated and front number plate information and rear portion to which the same vehicle identification information is assigned When there is no number plate information, the vehicle identification information of different lanes is compared, and the front license plate information and the rear license plate information to which the same vehicle identification information is assigned are associated with each other. Even if the lane is changed, it is possible to associate the front and rear license plate information with consistency as those of the same vehicle, and in comparison with the method of collectively holding information generated in multiple lanes, The processing speed for associating the front license plate information and the rear license plate information can be increased by the amount of time required for the search.

  Embodiments of a license plate information acquisition apparatus and license plate information acquisition method according to the present invention will be described below in detail with reference to the accompanying drawings. In the following, the outline and features of the license plate information acquisition device according to the first embodiment, the configuration of the license plate information acquisition device and the flow of processing will be described in order, and then the license plate information acquisition device according to the second embodiment. First, another embodiment will be described.

[Outline and Features of License Plate Information Acquisition Device According to Embodiment 1]
First, the outline and characteristics of the license plate information acquisition apparatus according to the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a diagram illustrating an overview and characteristics of a license plate information acquisition apparatus according to the first embodiment. FIG. 2 is a diagram illustrating an overview of the license plate information acquisition apparatus according to the first embodiment.

  As shown in FIG. 2, the license plate information acquisition device 10 is fixed to the pillar 1 standing on the side of the roadway, and the front camera 21, the rear camera 31, and the fish-eye lens camera 41 have the pillar 1 protruding above the roadway. The license plate information acquisition device 10, the front camera 21, the rear camera 31, and the fisheye lens camera 41 are connected by a dedicated cable.

  The front camera 21 always images the front point 3 that is the imaging area of the front camera 21, and outputs the image data to the license plate information acquisition device 10. The rear camera 31 is similarly the rear camera 31. The rear point 4, which is the imaging area, is always imaged, and the image data is output to the license plate information acquisition device 10. Further, the fisheye lens camera 41 always images a wide area including the front point 3 and the rear point 4. Similarly, the image data is output to the license plate information acquisition apparatus 10.

  Now, the outline of this license plate information acquisition device 10 is to acquire the front license plate information displayed on the front license plate of the vehicle 2 passing through the front point 3 and the vehicle 2 passing through the rear point 4. The rear license plate information displayed on the rear license plate is acquired, and the front license plate information and the rear license plate information are associated with each other. The license plate information acquisition apparatus 10 is mainly characterized in that the license plate information on the front and rear parts is associated with the same vehicle with consistency without depending on the movement of the vehicle.

  Explaining this main feature, the license plate information acquisition device 10 detects a vehicle that is about to pass through the front point 3 and continues until the detected vehicle passes from the front point 3 to the rear point 4. The vehicle is tracked while maintaining the state where the vehicle identification information for uniquely identifying the vehicle is given.

  Specifically, as shown in FIG. 1A, the license plate information acquisition apparatus 10 detects the vehicle 2 that is about to pass the front point 3 by processing the image data received from the fisheye lens camera 41. The vehicle identification information “A” is given (see (1) in FIG. 1A). And as shown to (B), (C), (D) of the figure, the number plate information acquisition apparatus 10 is vehicle identification information "" until the vehicle 2 passes the back point 4 from the front point 3. The vehicle 2 is tracked while maintaining the state of “A”.

  Next, the license plate information acquisition device 10 holds the vehicle identification information given to the vehicle in association with the front license plate information obtained from the vehicle, and is similarly given to the vehicle. The vehicle identification information is stored in association with the rear license plate acquired from the vehicle.

  Specifically, as shown in FIG. 1B, the license plate information acquisition apparatus 10 holds the vehicle 2 (hereinafter referred to as the vehicle “A”) that keeps track of the state to which the vehicle identification information “A” is given. ) Enters forward point 3, front license plate information (for example, serial number “00-11”) acquired by processing image data received from front camera 21 and vehicle identification information “A” Are stored and held in the front license plate information storage unit 24 (see (2) in FIG. 1B).

  As shown in FIG. 1D, the license plate information acquisition device 10 receives the rear number acquired by processing the image data received from the rear camera 31 when the vehicle “A” enters the rear point 4. Plate information (for example, serial number “00-11”) and vehicle identification information “A” are associated with each other and stored in the rear license plate information storage unit 34 (see (3) in FIG. 1D). ).

  Finally, the license plate information acquisition apparatus 10 compares the vehicle identification information and associates the front license plate information and the rear license plate information to which the same vehicle identification information is assigned.

  Specifically, as shown in FIG. 1D, the license plate information acquisition device 10 includes information held in the front license plate information storage unit 24, information held in the rear license plate information storage unit 34, and Are compared based on the vehicle identification information, and the front license plate information “00-11” to which the same vehicle identification information “A” is assigned is associated with the rear license plate information “00-11”. And stored in the front and rear license plate information storage unit 51 (see (4) in FIG. 1D). The license plate information acquisition apparatus 10 collates the associated front license plate information “00-11” with the rear license plate information “00-11” and transmits the collation result to a preset transmission destination. To do.

  For this reason, the license plate information acquisition apparatus 10 according to the first embodiment is not affected by the movement of the vehicle as described above, that is, the vehicle is located between the front imaging point and the rear imaging point. Even if the vehicle is temporarily stopped in the section, if another vehicle overtakes the temporarily stopped vehicle, or if the vehicle changes lanes in multiple lanes, the license plate information on the front and rear Can be associated with consistency as those of the same vehicle.

[Configuration of License Plate Information Acquisition Device According to Embodiment 1]
Next, the configuration of the license plate information acquisition apparatus 10 shown in FIGS. 1 and 2 will be described with reference to FIG. FIG. 3 is a block diagram showing a configuration of the license plate information acquisition apparatus 10. As shown in the figure, the license plate information acquisition device 10 includes a front license plate information generation device 20, a rear license plate information generation device 30, a vehicle tracking device 40, and a license plate information verification device 50. Is done.

  The front license plate information generating device 20 includes a front image temporary storage unit 22, a front license plate image storage unit 23, a front license plate information storage unit 24, a front vehicle detection processing unit 25, and a front unit. A license plate recognition unit 26 and a front license plate information reading unit 27 are provided and connected to the front camera 21. The front license plate information storage unit 24 corresponds to the “front information holding unit” recited in the claims.

  The front camera 21 always images a front point upstream of the roadway and outputs image data of the front point to the front image temporary storage unit 22 in real time. The front image temporary storage unit 22 temporarily stores the image data of the front point received via the front camera 21.

  The front license plate image storage unit 23 stores image data including a front license plate of the vehicle. Specifically, the front license plate image storage unit 23 receives and stores image data including the front license plate from a front license plate recognition unit 26 described later.

  The front license plate information storage unit 24 is a vehicle that is output from the front license plate information acquired from the vehicle and a vehicle identification information transmission unit 44 of the vehicle tracking device 40 to be described later when the vehicle enters the front point. The identification information is stored in association with each other. Specifically, front license plate information and vehicle identification information are received from a front license plate information reading unit 27 described later, and stored in association with each other. For example, as shown in FIG. 4, the front license plate information storage unit 24 stores vehicle identification information “A” and front license plate information “00-11” in association with each other.

  The front vehicle detection processing unit 25 processes the image data of the front point in real time and determines whether or not the vehicle has entered the image. Specifically, the front vehicle detection processing unit 25 reads the image data of the front point from the front image temporary storage unit 22 and recognizes a temporally varying region in the image (background difference or interframe difference). Or the like, or the pattern recognition technology or the like detects the entry of the vehicle in the image, and determines that the vehicle has entered, the image data including the front number plate in the front number plate recognition unit 26 described later. Outputs a signal instructing acquisition of.

  The front license plate recognition unit 26 recognizes the front license plate in the image, cuts out a region including the license plate, and acquires the image data. Specifically, when the front license plate recognition unit 26 receives a signal from the front vehicle detection processing unit 25, the front license plate recognition unit 26 reads the image data of the front point where the vehicle entered from the front image temporary storage unit 22, and the pattern recognition technology. For example, the front license plate in the image is recognized, a region including the license plate is cut out, and the image data is stored in the front license plate image storage unit 23.

  The front license plate information reading unit 27 generates front license plate information from image data including the front license plate. Specifically, the front license plate information reading unit 27 reads image data including the front license plate from the front license plate image storage unit 23, and is written on the front license plate by OCR (Optical Character Reader) technology or the like. Information is read and front license plate information is generated. Further, the front license plate information reading unit 27 receives the vehicle identification information from the vehicle identification information transmitting unit 44 provided in the vehicle tracking device 40 described later, and displays the vehicle identification information and the generated front license plate information in the front part. It is stored in the license plate information storage unit 24.

  For example, as shown in FIG. 5, the front license plate information reading unit 27 converts the serial number that is one of the information described in the front license plate from the image data 701 to text data 702 “79-36”. To generate front license plate information. Here, the front license plate information reading unit 27 reads only the serial number and generates the front license plate information. However, in addition to the serial number, the information written on the license plate, that is, the land transportation branch office code, etc. The application code or the vehicle type code may be read, and any one or more including the serial number may be generated as the front license plate information.

  Returning to the description of FIG. 3, the rear license plate information generation device 30 includes a rear image temporary storage unit 32, a rear license plate image storage unit 33, a rear license plate information storage unit 34, and a rear vehicle detection processing unit 35. The rear license plate recognition unit 36 and the rear license plate information reading unit 37 are connected to the rear camera 31. The rear image temporary storage unit 32, the rear license plate image storage unit 33, the rear vehicle detection processing unit 35, the rear license plate recognition unit 36, and the rear license plate information reading unit 37 are respectively a front image. The same processing as the temporary storage unit 22, the front license plate image storage unit 23, the front vehicle detection processing unit 25, the front license plate recognition unit 26, and the front license plate information reading unit 27 will be described. In the following, only the rear license plate information storage unit 34 will be described. The rear license plate information storage unit 34 corresponds to the “rear information holding unit” recited in the claims.

  The rear camera 31 always images a rear point downstream of the roadway and outputs image data of the rear point to the rear image temporary storage unit 32 in real time.

  The rear license plate information storage unit 34 includes rear license plate information acquired from the vehicle, and vehicle identification information output when the vehicle enters a rear point by the vehicle identification information transmission unit 44 of the vehicle tracking device 40 described later. Are stored in association with each other. Specifically, the rear license plate information and the vehicle identification information are received from the rear license plate information reading unit 37 and stored in association with each other. For example, as shown in FIG. 6, the rear license plate information storage unit 34 stores vehicle identification information “A” and front license plate information “00-11” in association with each other.

  Returning to the description of FIG. 3, the vehicle tracking device 40 includes a monitoring image storage unit 42, a vehicle tracking unit 43, and a vehicle identification information transmission unit 44, and is connected to the fisheye lens camera 41. The vehicle tracking unit 43 corresponds to “vehicle tracking means” recited in the claims.

  The fisheye lens camera 41 always captures a wide area, which is an area including the front point and the rear point, and outputs image data of the wide area to the monitoring image storage unit 42 in real time. The monitoring image storage unit 42 stores image data of a wide area received via the fisheye lens camera 41.

  The vehicle tracking unit 43 detects a vehicle that is about to pass through the front point, and provides vehicle identification information for uniquely identifying the vehicle until the detected vehicle passes from the front point to the rear point. The vehicle is tracked while maintaining the state assigned to.

  Specifically, the vehicle tracking unit 43 reads a wide range of image data from the monitoring image storage unit 42, recognizes a temporally varying region in the image (background difference, interframe difference, etc.), When a vehicle is detected in the image by the pattern recognition technology, the vehicle is tracked by a technology such as an optical flow while giving vehicle identification information to the vehicle. In addition, the vehicle tracking unit 43 transmits the vehicle identification information given to the vehicle and the vehicle identification information to the front license plate information generation device 20 when the vehicle passes the front point or the rear point, respectively. The transmission destination information indicating whether to transmit to the rear license plate information generation device 30 is output to the vehicle identification information transmission unit 44.

  For example, as shown in FIG. 7A, the vehicle tracking unit 43 gives vehicle identification information “A” to the vehicle 801 detected in the image, and tracks the vehicle “A”. Further, since the vehicle “A” passes through the front point, the vehicle tracking unit 43 uses the vehicle identification information “A” and the destination information indicating transmission to the front license plate information generation device 20 as the vehicle. It outputs to the identification information transmission part 44.

  Then, as shown in FIG. 7B, the vehicle tracking unit 43 recognizes the vehicle “A” and continues tracking even when the vehicle 801 is stopped between the front point and the rear point. Here, the vehicle tracking unit 43 detects the vehicle 802 behind the vehicle 801, adds vehicle identification information “B”, and tracks the vehicle “B”.

  As shown in FIG. 7C, the vehicle tracking unit 43 recognizes the vehicle 802 as the vehicle “B” and continues to track the vehicle 802 even when the vehicle 802 overtakes the vehicle 801. 801 is recognized as the vehicle “A” and tracking is continued. The vehicle tracking unit 43 sends the vehicle identification information “B” to the front license plate information generation device 20 when the vehicle “B” passes the front point and the rear point, respectively. Information on the transmission destination indicating transmission or information on the transmission destination indicating transmission to the rear license plate information generation device 30 is output to the vehicle identification information transmission unit 44.

  Then, as illustrated in FIG. 7D, the vehicle tracking unit 43 recognizes the vehicle “A” and continues tracking even when the vehicle 801 starts. The vehicle tracking unit 43 uses the vehicle identification information “A” and the transmission destination information indicating transmission to the rear license plate information generating device 30 when the vehicle “A” passes the rear point. The data is output to the transmission unit 44.

  Returning to the description of FIG. 3, the vehicle identification information transmission unit 44 outputs the vehicle identification information to the front license plate information generation device 20 or the rear license plate information generation device 30. Specifically, when the vehicle identification information transmitting unit 44 receives the vehicle identification information from the vehicle tracking unit 43, the front number plate information generating device 20 or the rear number is based on the transmission destination information received together with the vehicle identification information. The vehicle identification information is transmitted to the plate information generation device 30.

  The license plate information matching device 50 includes a front and rear part number plate information storage unit 51, a correspondence processing unit 52, a matching unit 53, and a transmission unit 54. The association processing unit 52 corresponds to “front / rear association unit” recited in the claims.

  The front / rear license plate information storage unit 51 stores front license plate information and rear license plate information in association with each other. Specifically, the front license plate information and the rear license plate information are received from the association processing unit 52 described later, and stored in association with each other. For example, as shown in FIG. 8, the front and rear number plate information storage unit 51 stores front number plate information “00-11” and rear number plate information “00-11” in association with each other.

  The correspondence processing unit 52 compares the vehicle identification information stored in the front license plate information storage unit 24 and the rear license plate information storage unit 34, and the front license plate information to which the same vehicle identification information is assigned and Correlate the rear license plate information. Specifically, when a predetermined time (for example, every 6 hours) elapses, the front license plate information storage unit 24 and the rear license plate information storage unit 34 are based on the vehicle identification information associated with the license plate information. The front license plate information and the rear license plate information are read from and stored in the front and rear license plate information storage unit 51 in association with each other. When the association processing unit 52 reads all the information stored in the front license plate information storage unit 24 and the rear license plate information storage unit 34, the front license plate information associated with the verification unit 53 to be described later. And a signal for instructing collation of the rear license plate information.

  The collation unit 53 compares the front license plate information and the rear license plate information associated with each other by the association processing unit 52 to collate whether or not they belong to the same vehicle. Specifically, when receiving the signal from the association processing unit 52, the collation unit 53 reads out the associated front license plate information and rear license plate information from the front and rear license plate information storage unit 51 and compares them. If both are the same, a signal instructing transmission of information relating to “normal vehicle passage” is output to the transmission unit 54, and if both are different, transmission of information relating to “abnormal vehicle passage” is instructed. The signal to be output is output to the transmission unit 54.

  The transmission part 54 transmits the information regarding the presence or absence of abnormality of the passing vehicle to a preset transmission destination (for example, a VICS center or each prefectural traffic control center). Specifically, when a signal is received from the verification unit 53, the information related to “normal vehicle passage” or the information related to “abnormal vehicle passage” is transmitted to a preset transmission destination.

[Processing of License Plate Information Acquisition Device According to Embodiment 1]
Next, various processes of the license plate information acquisition apparatus 10 will be described with reference to FIGS. 9 is a flowchart showing the flow of the front license plate information generation process, FIG. 10 is a flowchart showing the flow of the rear license plate information generation process, and FIG. 11 is a flowchart showing the flow of the vehicle tracking process. FIG. 12 is a flowchart showing the flow of the license plate information association process, and FIG. 13 is a flowchart showing the flow of the license plate information matching process.

(1) Front License Plate Information Generation Processing As shown in FIG. 9, the front license plate information generation device 20 detects a vehicle in the image of the front point by the front vehicle detection processing unit 25 (Yes in step S901). Then, the front license plate is recognized by the front license plate recognition unit 26 in the image of the front point (step S902), the area including the front license plate is cut out, and the image data is stored in the front license plate image storage unit 23. (Step S903).

  Then, the front license plate information generation device 20 generates front license plate information by the front license plate information reading unit 27 (step S904), and receives vehicle identification information from the vehicle identification information transmission unit 44 (step S905). (Yes), the vehicle identification information and the front license plate information are associated with each other and stored in the front license plate image storage unit 23 (step S906), and the process ends.

(2) Rear License Plate Information Generation Processing As shown in FIG. 10, the rear license plate information generation device 30 detects the vehicle in the rear point image by the rear vehicle detection processing unit 35 (Yes in step S1001), and the rear number. The plate number recognition unit 36 recognizes the rear license plate in the rear point image (step S1002), cuts out the area including the rear number plate, and stores the image data in the rear number plate image storage unit 33 (step S1003). .

  Then, the rear license plate information generation device 30 generates the rear license plate information by the rear license plate information reading unit 37 (step S1004), and receives the vehicle identification information from the vehicle identification information transmission unit 44 (Yes in step S1005). The vehicle identification information and the rear license plate information are associated with each other and stored in the rear license plate image storage unit 33 (step S1006), and the process ends.

(3) Vehicle Tracking Process As shown in FIG. 11, when the vehicle tracking device 40 detects a vehicle in the image of the monitoring range by the vehicle tracking unit 43 (step S1101), the vehicle tracking device 40 tracks the vehicle by providing vehicle identification information. (Step S1102). When the vehicle being tracked enters the forward point (step S1103), the vehicle tracking device 40 transmits the vehicle identification information given to the vehicle to the front license plate information reading unit 27 by the vehicle identification information transmitting unit 44. (Step S1104). Then, the vehicle tracking device 40 continues to track the vehicle, and when the vehicle enters the rear point (step S1105), the vehicle identification information given to the vehicle is read by the rear license plate information by the vehicle identification information transmitting unit 44. It transmits to the part 37 (step S1106), and a process is complete | finished.

(4) Correspondence processing between front license plate information and rear license plate As shown in FIG. 12, the license plate information collation apparatus 50, when a predetermined time has elapsed (Yes in step S1201), causes the correspondence processing unit 52 to One front license plate information is acquired from the license plate information storage unit 24 (step S1202), and the same from the rear license plate information storage unit 34 based on the vehicle identification information associated with the front license plate information. The rear license plate information associated with the vehicle identification information is acquired (step S1203), and both are associated with each other and stored in the front and rear license plate information storage unit 51 (step S1204). If the license plate information matching device 50 has not acquired all the front license plate information (No at step S1205), the license plate information collating device 50 continues the same operation until all the front license plate information is acquired. When the front license plate information is acquired (Yes at step S1205), the processing by the association processing unit 52 is terminated.

(5) License Plate Information Collation Processing As shown in FIG. 13, when the collation unit 53 receives a signal from the association processing unit 52 (step S1301), the license plate information collation device 50 is associated with the front number. The plate information and the rear license plate information are acquired from the front and rear license plate information storage unit 51 by the verification unit 53, and both are verified (step S1302). When the license plate information matching device 50 matches the two (Yes in step S1303), the transmission unit 54 transmits information related to “passing through the normal vehicle” to a preset transmission destination (step S1304). ) If they are different (No at Step S1303), the transmission unit 54 transmits information related to “abnormal vehicle passage” to a preset transmission destination (Step S1305). Then, the license plate information collating apparatus 50 determines that all collations for the associated front license plate information and rear license plate information stored in the front and rear license plate information storage unit 51 have not been completed (No in step S1306). ), The same operation is continued until all the collations are completed, and when all the collations are completed (Yes in step S1306), the processes by the collation unit 53 and the transmission unit 54 are terminated.

[Effect of Example 1]
As described above, according to the first embodiment, a vehicle that is about to pass through the front point is detected, and the vehicle is uniquely identified until the detected vehicle passes from the front point to the rear point. The state in which the vehicle identification information is given to the vehicle is maintained, the vehicle is tracked, the vehicle identification information given to the vehicle from which the front license plate information is obtained is obtained, and the vehicle identification information obtained before the vehicle is obtained. The part number plate information and the vehicle identification information are stored in association with each other, the vehicle identification information given to the vehicle from which the rear part number plate information is obtained is obtained, and the rear number plate information and the vehicle obtained from the vehicle are obtained. The identification number is held in association with each other, the vehicle identification information held is compared, and the front license plate information and the rear number assigned the same vehicle identification information. Since associates plate information, without being affected by the movements of the vehicle, it is possible to associate with the integrity of the front and rear license plate information as the same vehicle. In other words, even when the vehicle pauses between the front and rear points, re-starts and enters the rear point, the front and rear license plate information is consistently associated with the same vehicle. In addition, even when another vehicle overtakes a temporarily stopped vehicle, it is possible to associate the front and rear license plate information with the same vehicle in a consistent manner. Even when the vehicle changes lanes, it is possible to associate the front and rear license plate information with the same vehicle with consistency.

  In addition, according to the first embodiment, by processing an image obtained by imaging a region including the front point and the rear point, a vehicle that attempts to pass the front point is detected, and vehicle identification information is transmitted to the vehicle. Since the vehicle is tracked while maintaining the imparted state, it is possible to track the vehicle even in a situation where a plurality of vehicles are dense, as compared with a method using electromagnetic waves.

  Further, according to the first embodiment, the fisheye lens camera connected to the vehicle tracking device is installed on the pillar located between the front point and the rear point together with the front camera and the rear camera. In addition to detecting, the vehicle is tracked while maintaining the state where the vehicle identification information is given to the vehicle. Therefore, compared to the method of installing an imaging unit that outputs image data to the vehicle tracking device at a remote position, Such costs can be reduced.

  Also, according to the first embodiment, the front license plate information and the rear license plate information associated by the license plate information verification device are compared to verify whether they are of the same vehicle. It is possible to improve the accuracy of finding the. That is, since the license plate information acquisition device collates the front license plate information and the rear license plate information in a consistent state, it is possible to increase the accuracy of finding a violation vehicle.

  In the first embodiment, the method of associating the vehicle front license plate information and the rear license plate information in one lane has been described. In the second embodiment, the vehicle front license plate information and the rear license plate in two lanes are described. A method for associating information will be described.

  First, an overview of the license plate information acquisition apparatus according to the second embodiment will be described with reference to FIG. FIG. 14 is a diagram illustrating an overview of the license plate information acquisition apparatus according to the second embodiment.

  As shown in the figure, the license plate information acquisition device 60 is fixed to the pillar 1 standing on the side of the rear roadway in the same manner as in the first embodiment, and includes a first lane front camera 71 and a first lane rear part. The camera 81 and the fisheye lens camera 91 are fixed to a portion where the pillar 1 protrudes upward in the roadway. The second lane front camera 101 and the second lane rear camera 111 are installed on the pillar 5 standing on the side of the roadway in front, and the license plate information acquisition device 60 and the first lane front camera 71 are installed. The first lane rear camera 81, the fisheye lens camera 91, the second lane front camera 101, and the second lane rear camera 111 are connected by a dedicated cable.

  The first lane front camera 71 always images the first lane front point 6 which is the imaging area of the first lane front camera 71, outputs the image data to the license plate information acquisition device 60, and Similarly, the lane rear camera 81 always images the first lane rear point 7 which is the imaging area of the first lane rear camera 81 and outputs the image data to the license plate information acquisition device 60. The second lane front camera 101 always images the second lane front point 8 which is the imaging area of the second lane front camera 101, and outputs the image data to the license plate information acquisition device 60. Similarly, the second lane rear camera 111 constantly images the second lane rear point 9 which is the imaging area of the second lane rear camera 111 and outputs the image data to the license plate information acquisition device 60. Further, the fisheye lens camera 91 always images a wide area including the first lane front point 6, the first lane rear point 7, the second lane front point 8, and the second lane rear point 9, and similarly, the image data Is output to the license plate information acquisition device 60.

[Configuration of License Plate Information Acquisition Device According to Example 2]
Next, the configuration of the license plate information acquisition apparatus 60 shown in FIG. 14 will be described with reference to FIG. FIG. 15 is a block diagram showing the configuration of the license plate information acquisition device 60. As shown in the figure, the license plate information acquisition device 60 includes a first lane front license plate information generation device 70, a first lane rear license plate information generation device 80, a vehicle tracking device 90, and a second lane. It consists of a front license plate information generation device 100, a second lane rear license plate information generation device 110, and a license plate information collation device 120.

  The first lane front number plate information generating device 70 includes a first lane front image temporary storage unit 72, a first lane front number plate image storage unit 73, and a first lane front number plate information storage unit. 74, a first lane front vehicle detection processing unit 75, a first lane front license plate recognition unit 76, and a first lane front license plate information reading unit 77, and a first lane front camera 71, Connected. The first lane front license plate information storage unit 74 corresponds to “front information holding means” described in the claims.

  The first lane rear license plate information generator 80 includes a first lane rear image temporary storage unit 82, a first lane rear license plate image storage unit 83, a first lane rear license plate information storage unit 84, A one-lane rear vehicle detection processing unit 85, a first lane rear number plate recognition unit 86, and a first lane rear number plate information reading unit 87 are connected to the first lane rear camera 81. The first lane rear license plate information storage unit 84 corresponds to the “rear information holding unit” recited in the claims.

  The vehicle tracking device 90 includes a monitoring image storage unit 92, a vehicle tracking unit 93, and a vehicle identification information transmission unit 94, and is connected to the fisheye lens camera 91. The vehicle tracking unit 93 corresponds to “vehicle tracking means” described in the claims.

  The second lane front license plate information generating device 100 includes a second lane front image temporary storage unit 102, a second lane front license plate image storage unit 103, and a second lane front license plate information storage unit. 104, a second lane front vehicle detection processing unit 105, a second lane front license plate recognition unit 106, and a second lane front license plate information reading unit 107, and a second lane front camera 101, Connected. The second lane front license plate information storage unit 104 corresponds to “front information holding means” described in the claims.

  The second lane rear license plate information generator 110 includes a second lane rear image temporary storage unit 112, a second lane rear license plate image storage unit 113, a second lane rear license plate information storage unit 114, A two-lane rear vehicle detection processing unit 115, a second lane rear license plate recognition unit 116, and a second lane rear license plate information reading unit 117 are provided, and are connected to the second lane rear camera 111. The second lane rear license plate information storage unit 114 corresponds to “rear information holding means” described in the claims.

  The license plate information collation apparatus 120 includes a front / rear number plate information storage unit 121, a correspondence processing unit 122, a collation unit 123, and a transmission unit 124. The association processing unit 122 corresponds to “front / rear association means” recited in the claims.

  It should be noted that the first lane front image temporary storage unit 72 and the second lane front image temporary storage unit 102 in the first lane front license plate information generation device 70 and the second lane front license plate information generation device 100, and A first lane front license plate image storage unit 73 and a second lane front license plate image storage unit 103; a first lane front license plate information storage unit 74; a second lane front license plate information storage unit 104; A first lane front vehicle detection processing unit 75 and a second lane front vehicle detection processing unit 105, a first lane front number plate recognition unit 76, a second lane front number plate recognition unit 106, and a first lane front The license plate information reading unit 77 and the second lane front number plate information reading unit 107 are respectively the front part number according to the first embodiment. Front image temporary storage unit 22, front license plate image storage unit 23, front license plate information storage unit 24, front vehicle detection processing unit 25, and front license plate recognition unit in plate information generating device 20 26 and the same processing as that performed by the front license plate information reading unit 27, and the description thereof will be omitted.

  The first lane rear license plate information generator 80, the second lane rear license plate information generator 110, the first lane rear image temporary storage unit 82, the second lane rear image temporary storage unit 112, and the first lane rear number. Plate image storage unit 83 and second lane rear license plate image storage unit 113, first lane rear license plate information storage unit 84, second lane rear license plate information storage unit 114, and first lane rear vehicle detection processing unit 85 The second lane rear vehicle detection processing unit 115, the first lane rear license plate recognition unit 86, the second lane rear license plate recognition unit 116, the first lane rear license plate information reading unit 87, and the second lane rear license plate. The information reading unit 117 is a rear number according to the first embodiment. Rear image temporary storage unit 32, rear license plate image storage unit 33, rear license plate information storage unit 34, rear vehicle detection processing unit 35, rear license plate recognition unit 36, and rear number in plate information generating device 30 Since the same processing as that of the plate information reading unit 37 is performed, the description thereof is omitted.

  Further, the monitoring image storage unit 92 in the vehicle tracking device 90 performs the same processing as the monitoring image storage unit in the vehicle tracking device 40 according to the first embodiment, and thus the description thereof is omitted, and the front and rear part numbers in the license plate information matching device 120 are omitted. The plate information storage unit 121, the verification unit 123, and the transmission unit 124 are respectively the front and rear license plate information storage unit 51, the verification unit 53, and the transmission unit 54 in the license plate information verification device 50 according to the first embodiment. Since the same processing is performed, the description is omitted. Therefore, only the vehicle tracking unit 93, the vehicle identification information transmission unit 94, and the association processing unit 122 will be described below.

  The vehicle tracking unit 93 detects a vehicle that is about to pass through the first lane forward point or the second lane forward point, and the detected vehicle moves from the first lane forward point or the second lane forward point to the first lane backward point or The vehicle is tracked while maintaining the state in which the vehicle identification information for uniquely identifying the vehicle is given to the vehicle until the vehicle passes the second lane point.

  Specifically, the vehicle tracking unit 93 reads image data of a wide area from the monitoring image storage unit 92, and when the vehicle is detected in the image, the vehicle tracking unit 93 tracks the vehicle while giving vehicle identification information to the vehicle. The vehicle tracking unit 93 also includes vehicle identification information given to the vehicle when the vehicle passes through the first lane front point, the second lane front point, the first lane rear point, or the second lane rear point, and The vehicle identification information is transmitted to the first lane front license plate information generation device 70, transmitted to the first lane rear license plate information generation device 80, or transmitted to the second lane front license plate information generation device 100. Or the transmission destination information indicating whether to transmit to the second lane rear license plate information generation device 110 is output to the vehicle identification information transmission unit 94.

  The vehicle identification information transmission unit 94 transmits vehicle identification information to the first lane front license plate information generation device 70, the first lane rear license plate information generation device 80, the second lane front license plate information generation device 100, or the second lane. The information is output to the rear license plate information generation device 110.

  Specifically, the vehicle identification information transmission unit 94 receives a vehicle from the vehicle tracking unit 93 when the vehicle passes the first lane front point, the second lane front point, the first lane rear point, or the second lane rear point. When the identification information is received, the first lane front license plate information generation device 70, the first lane rear license plate information generation device 80, and the second lane front license plate based on the destination information received together with the vehicle identification information. The vehicle identification information is transmitted to the information generation device 100 or the second lane rear license plate information generation device 110.

  The correspondence processing unit 122 includes a first lane front license plate information storage unit 74, a first lane rear license plate information storage unit 84, a second lane front license plate information storage unit 104, and a second lane rear license plate information storage. The vehicle identification information stored in the unit 114 is compared, and the front license plate information and the rear license plate information to which the same vehicle identification information is assigned are associated.

  Specifically, when a predetermined time (for example, every 6 hours) elapses, the first lane front license plate information storage unit 74, the first lane rear part, based on the vehicle identification information associated with the license plate information. The front license plate information and the rear license plate information are read from the license plate information storage section 84, the second lane front license plate information storage section 104, and the second lane rear license plate information storage section 114, and the front and rear sections are associated with each other. It is stored in the license plate information storage unit 121. The processing of the association processing unit 122 will be described later with reference to FIG.

[Processing of License Plate Information Acquisition Device According to Embodiment 2]
Next, processing of the license plate information acquisition device 60 will be described with reference to FIG. FIG. 16 is a flowchart illustrating the flow of the license plate information association processing according to the second embodiment.

  As shown in FIG. 16, the license plate information matching device 120, when a predetermined time has elapsed (Yes in step S1601), causes the corresponding processing unit 122 to change the first lane front from the first lane front license plate information storage unit 74. Part number plate information is acquired (step S1602), and the same vehicle identification information is handled from the first lane rear number plate information storage unit 84 based on the vehicle identification information associated with the first lane front number plate information. The attached first lane rear license plate information is searched (step S1603).

  When the license plate information collating device 120 finds the first lane rear license plate information associated with the same vehicle identification information by the association processing unit 122 (Yes in step S1604), the license plate information collating device 120 associates the two with each other. The license plate information is stored in the license plate information storage unit 121 (step S1605), and if it is not found (No in step S1604), the second lane rear license plate information storage unit 114 is searched and the second license plate information associated with the same vehicle identification information is searched. Two-lane rear license plate information is found, and both are associated and stored in the front and rear license plate information storage unit 121 (step S1606).

  If the license plate information collating device 120 has not acquired all the first lane front license plate information (No in step S1607), the license plate information collating device 120 is associated until it acquires all the first lane front license plate information. If the same operation is continued by the processing unit 122 and all the first lane front number plate information is acquired (Yes in step S1607), the corresponding processing unit 122 similarly similarly uses the second lane front number plate information storage unit 104. One second lane front license plate information is acquired (step S1608), and from the second lane rear license plate information storage unit 114 based on the vehicle identification information associated with the second lane front license plate information. The second lane rear license plate information associated with the same vehicle identification information is searched (step by step). Flop S1609).

  Then, when the second lane rear license plate information associated with the same vehicle identification information is found (Yes at step S1610), the license plate information matching device 120 associates the two with the corresponding processing unit 122, and then Stored in the part number plate information storage unit 121 (step S1611), and if not found (No in step S1610), the first lane rear part number plate information storage unit 84 is searched, and the number corresponding to the same vehicle identification information is searched. One-lane rear license plate information is found, and both are associated and stored in the front and rear license plate information storage unit 121 (step S1612).

  If the license plate information collation device 120 has not acquired all the second lane front license plate information (No in step S1613), the license plate information collating device 120 is associated until it acquires all the first lane front license plate information. If the same operation is continued by the processing unit 122 and all the second lane front license plate information is acquired (Yes at step S1613), the processing by the association processing unit 122 is terminated.

  In the second embodiment, the license plate information acquisition device in two lanes has been described. However, in a plurality of lanes of two or more lanes, a front camera and a rear camera are installed for each lane, and front license plate information for each lane is provided. If the rear license plate information is generated, it is possible to associate them with consistency.

[Effect of Example 2]
As described above, according to the second embodiment, the front license plate information and the rear license plate information are acquired for each lane in a plurality of lanes, and the vehicle is about to pass the front point for each lane. The vehicle is tracked while maintaining the state in which the vehicle identification information is given to the vehicle until the detected vehicle passes through the rear point of any lane from the front point. Plate information and vehicle identification information in association with each other, comparing vehicle identification information of the same lane, if there is front license plate information and rear license plate information to which the same vehicle identification information is given, The front license plate information and the rear license plate information are associated with each other, and the front license plate information is assigned the same vehicle identification information. In the case where there is no rear license plate information, the vehicle identification information of different lanes is compared, and the front license plate information and the rear license plate information to which the same vehicle identification information is assigned are associated. Even if the vehicle changes lanes, the front and rear license plate information can be consistently associated with the same vehicle, and compared to a method that collectively holds information generated in multiple lanes. Thus, the processing speed for associating the front license plate information and the rear license plate information can be increased by the amount of time required for the search.

  By the way, although the license plate information acquisition apparatus which concerns on Example 1 or 2 was demonstrated until now, this invention may be implemented with a various different form other than an above-described Example. Therefore, in the following, as license plate information acquisition apparatuses according to the third embodiment, different embodiments will be described by dividing them into (1) to (7).

(1) Matching Condition In the above-described first or second embodiment, the association processing unit of the license plate information acquisition device is based on the front license plate information and the rear part only based on the vehicle identification information associated with the license plate information. Although the case where the license plate information is associated with consistency has been described, the present invention is not limited to this, and consistency is determined not only by the vehicle identification information but also by vehicle color information and shape information. You may do it.

  For example, in the license plate information acquisition apparatus 10 according to the first embodiment, the vehicle tracking unit 43 includes the vehicle color information and shape information acquired from the image data in addition to the vehicle identification information given to the vehicle. 44. By doing so, for example, the front license plate information storage unit 24 stores the front license plate information in association with vehicle identification information, vehicle color information, and vehicle shape information. Then, the association processing unit 52 associates the front license plate information and the rear license plate information with consistency based on the vehicle identification information, the vehicle color information, and the vehicle shape information. That is, the association processing unit 52 associates the front license plate information and the rear license plate information with consistency on condition that the vehicle identification information, the vehicle color information, and the vehicle shape information are all the same. May be performed.

  Thus, the color information and shape information of the vehicle from which the front license plate information was acquired, and the color information and shape information of the vehicle from which the rear license plate information was acquired, respectively, the color information and shape information, Front number plate information and rear number assigned with the same vehicle identification information, color information and shape information by comparing the vehicle identification information, color information and shape information in correspondence with the license plate information and vehicle identification information Since the plate information is associated with each other, there are a plurality of criteria for determining consistency, and the reliability of consistency can be increased.

(2) Time information In the above-described first or second embodiment, the association processing unit of the license plate information acquisition apparatus is configured based on the front license plate information and the rear part based only on the vehicle identification information associated with the license plate information. The case where the license plate information is associated with the consistency has been described, but the present invention is not limited to this, and in addition to the vehicle identification information, the front portion is information on the time when the vehicle passes the front point. Consistency may be determined based on time information or rear time information that is information on the time of passing through a rear point.

  For example, in the license plate information acquisition device 10 according to the first embodiment, if the vehicle tracking device 40 cannot track the vehicle for some reason, the front license plate information storage unit 24 or the rear license plate information storage unit 34 Stores front license plate information and rear license plate information not associated with vehicle identification information. Therefore, the vehicle tracking device 40 transmits the front time information and the rear time information to the front license plate information generation device 20 and the rear license plate information generation device 30, respectively, in addition to the vehicle identification information, and stores the front license plate information. In addition to the vehicle identification information, the front license plate information associated with the front time information and the rear license plate information associated with the rear time information are stored in the unit 24 and the rear license plate information storage unit 34. The

  And the corresponding | compatible process part 52 judges consistency with respect to the front number plate information and rear part number plate information which are not matched with vehicle identification information based on front time information and rear part time information ( For example, consistency is determined based on the fact that the difference between the front time information and the rear time information is within a predetermined time), and the two are associated with each other and stored in the front / rear license plate information storage unit 51.

  In this manner, time information indicating the time when the front license plate information is acquired and time information indicating the time when the rear license plate information is acquired are respectively acquired and associated with the license plate information and the vehicle identification information. When the vehicle identification information and the time information are compared, and the front license plate information and the rear license plate information to which the same vehicle identification information or adjacent time information is assigned are associated with each other, so that the vehicle cannot be tracked. However, it is possible to associate with consistency based on the time information.

(3) Installation position In Example 1 or 2 described above, the license plate information acquisition device has been described as being fixedly installed on one pillar, but the present invention is not limited to this, For example, as shown in FIG. 17, in the license plate information acquisition apparatus 10 according to the first embodiment, a wide area that includes the front point and the rear point is imaged, and the image data is output to the vehicle tracking unit 42. An imaging unit 130 that replaces the fisheye lens camera 41 may be provided, and the imaging unit 130 may be fixed to the pillar 170 located downstream of the pillar 1. The imaging unit 130 does not need to be equipped with a fisheye lens. For example, the imaging unit 130 is equipped with a wide-angle lens or the like to image a wide area and outputs the image data to the vehicle tracking unit 43.

  In this way, the front camera that images the front license plate of the vehicle passing through the front point and the rear license plate of the vehicle passing through the rear point are arranged on the column located upstream or downstream from the front point and the rear point. Since it is installed separately from the rear camera that captures the image and detects the vehicle that is about to pass through the front point and tracks the vehicle while maintaining the state in which the vehicle identification information is given to the vehicle, for example, the monitoring range is imaged. Therefore, compared with the method in which the vehicle tracking means using the fisheye lens is installed on the same column, the processing speed of the vehicle tracking can be increased by the amount of time required for correcting the image captured by the fisheye lens. It becomes.

(4) Vehicle Tracking In the first or second embodiment described above, the license plate information acquisition device senses a vehicle by imaging a wide area, which is an area including the front point and the rear point, and processing the image data. However, the present invention is not limited to this. For example, an electromagnetic wave such as a millimeter wave is transmitted to a wide area, and the vehicle is detected by capturing the reflected wave. You may make it track.

  In this way, by processing the reflected wave returned by the electromagnetic wave transmitted toward the area including the front point and the rear point, the vehicle that is about to pass the front point is detected, and the vehicle identification information is stored in the vehicle. Since the vehicle is tracked while maintaining the state given to the vehicle, it is possible to track the vehicle even in situations where it is difficult to recognize the image (for example, at night) compared to the method using image recognition technology. Become.

(5) License plate information storage unit In the second embodiment, the license plate information acquisition device 60 has described the case where the front license plate information and the rear license plate information are stored separately for each lane. For example, the first lane front number plate information storage unit 74 and the second lane front number plate information storage unit 104 are integrated, and the first lane rear number plate is not limited thereto. Provide a rear storage unit that integrates the information storage unit 84 and the second lane rear license plate information storage unit 114 so that the front license plate information and the rear license plate information are held together without being divided into lanes. Also good. In this case, the association processing unit 122 acquires the front license plate information from the front storage unit without distinguishing between lanes, and searches the rear storage unit, thereby matching the same vehicle identification information. Search the rear license plate information and associate them.

(6) System Configuration, etc. The processing procedures, control procedures, specific names, information including various data and parameters shown in the above documents and drawings can be arbitrarily changed unless otherwise specified. For example, in the processing procedure shown in FIG. 16, the case where the first lane front license plate information is sequentially acquired from the first lane front license plate information storage unit has been described, but the present invention is not limited to this. For example, the second lane front license plate information may be sequentially acquired from the second lane front license plate information storage unit. Further, for example, the vehicle identification information shown in FIG. 1 is written in alphabets, but the present invention is not limited to this. For example, at least a license plate information acquisition device such as a number can uniquely identify a vehicle. If it is.

  Each component of the illustrated devices (the license plate information acquisition device 10 and the license plate information acquisition device 60) is functionally conceptual and does not necessarily have to be physically configured as illustrated. That is, the specific form of distribution / integration of each device is not limited to the illustrated one. For example, the vehicle tracking unit 43 and the vehicle identification information transmission unit 44 are integrated, or the collation unit 53 and the transmission unit 54 are integrated. For example, all or a part thereof can be configured to be functionally or physically distributed / integrated in an arbitrary unit according to various loads or usage conditions. Further, all or any part of each processing function performed in each device may be realized by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware by wired logic.

(7) License plate information acquisition program In the above-described first or second embodiment, the case where various processes are realized by hardware logic has been described. However, the present invention is not limited to this and is prepared in advance. The program may be realized by executing the program on a computer. Therefore, in the following, an example of a computer that executes a license plate information acquisition program having the same function as the license plate information acquisition apparatus 10 shown in the first embodiment will be described with reference to FIG. FIG. 18 is a diagram illustrating a computer that executes a license plate information acquisition program.

  As shown in the figure, a computer 130 serving as a license plate information acquisition device has a front camera 131, a rear camera 132, a fisheye lens camera 133, a CPU 134, a ROM 135, an HDD 136, a RAM 137, and an output antenna 138 connected by a bus 139 or the like. Composed.

  In the ROM 135, a license plate information acquisition program that exhibits the same function as the license plate information acquisition device 10 shown in the first embodiment, that is, as shown in FIG. Part number plate recognition program 135b, front part number plate information reading program 135c, vehicle tracking program 135d, vehicle identification information transmission program 135e, rear part vehicle detection processing program 135f, rear part number plate recognition program 135g, rear part number A plate information reading program 135h, a correspondence processing program 135i, a collation program 135j, and a transmission program 135k are stored in advance. In addition, about these programs 135a-135k, you may integrate or disperse | distribute suitably like each component of the license plate information acquisition apparatus 10 shown in FIG.

  And CPU134 reads these programs 135a-135k from ROM135, and as shown in FIG. 18, each program 135a-135k is the front vehicle detection process 134a, the front license plate recognition process 134b. Front license plate information reading process 134c, vehicle tracking process 134d, vehicle identification information transmission process 134e, rear vehicle detection processing process 134f, rear license plate recognition process 134g, rear license plate information reading process 134h, association processing process 134i, It functions as a collation process 134j and a transmission process 134k. Each of the processes 134a to 134k includes the front vehicle detection processing unit 25, the front license plate recognition unit 26, the front license plate information reading unit 27, the vehicle tracking unit 43, and the vehicle identification information transmission unit 44 illustrated in FIG. , Corresponding to the rear vehicle detection processing unit 35, the rear license plate recognition unit 36, the rear license plate information reading unit 37, the association processing unit 52, the verification unit 53, and the transmission unit 54.

  Further, as shown in FIG. 18, the HDD 136 has a front image data 136a, a front license plate image data 136b, a front license plate information table 136c, monitoring image data 136d, a rear image data 136e, A rear license plate image data 136f, a rear license plate information table 136g, and a front and rear license plate information table 136h are provided. The front image data 136a, the front license plate image data 136b, the front license plate information table 136c, the monitoring image data 136d, the rear image data 136e, the rear license plate image data 136f, the rear license plate information table 136g, and the front and rear portions The license plate information table 136h includes a front image temporary storage unit 22, a front license plate image storage unit 23, a front license plate information storage unit 24, a monitoring image storage unit 42, and a rear image shown in FIG. These correspond to the temporary storage unit 32, the rear license plate image storage unit 33, the rear license plate information storage unit 34, and the front and rear license plate information storage unit 51, respectively.

  The CPU 134 then controls the front image data 136a, the front license plate image data 136b, the front license plate information table 136c, the monitoring image data 136d, the rear image data 136e, the rear license plate image data 136f, and the rear license plate information table 136g. The front image data 137a, the front license plate image data 137b, the front license plate information table 137c, the monitoring image data 137d, the rear image data 137e, the rear license plate image data 137f, the rear The license plate information table 137g and the front and rear license plate information table 137h are read out and stored in the RAM 137, and the front image data stored in the RAM 137 37a, front license plate image data 137b, front license plate information table 137c, monitoring image data 137d, rear image data 137e, rear license plate image data 137f, rear license plate information table 137g and front and rear license plate information table 137h Based on the above, vehicle tracking, front license plate information generation, etc. are executed.

  The above-described programs 135a to 135k are not necessarily stored in the ROM 135 from the beginning. For example, a flexible disk (FD), a CD-ROM, an MO disk, a DVD disk, an optical disk inserted into the computer 130, and the like. Via a “portable physical medium” such as a magnetic disk or an IC card, or a “fixed physical medium” such as an HDD provided inside or outside the computer 130, or via a public line, the Internet, a LAN, a WAN, etc. Each program may be stored in “another computer (or server)” connected to the computer 130, and the computer 130 may read and execute each program from these.

  As described above, the license plate information acquisition device and the license plate information acquisition method according to the present invention acquire the front license plate information displayed on the front license plate of the vehicle passing through the front point, and the rear point. It is useful for acquiring the rear license plate information displayed on the rear license plate of the vehicle passing through the vehicle and associating the front license plate information with the rear license plate information, and particularly depending on the movement of the vehicle. Rather, it is suitable for matching the license plate information of the front part and the rear part of the same vehicle with consistency.

FIG. 1 is a diagram for explaining the outline and features of a license plate information acquisition apparatus. FIG. 2 is a diagram showing an overview of the license plate information acquisition apparatus. FIG. 3 is a block diagram showing the configuration of the license plate information acquisition apparatus. FIG. 4 is a diagram illustrating an example of information stored in the front license plate information storage unit. FIG. 5 is a diagram illustrating an example of reading license plate information. FIG. 6 is a diagram illustrating an example of information stored in the rear license plate information storage unit. FIG. 7 is a diagram illustrating an example of a situation in which a vehicle is tracked. FIG. 8 is a diagram illustrating an example of information stored in the front and rear license plate information storage unit. FIG. 9 is a flowchart showing the flow of the front license plate information generation process. FIG. 10 is a flowchart showing the flow of the rear license plate information generation process. FIG. 11 is a flowchart showing the flow of the vehicle tracking process. FIG. 12 is a flowchart showing the flow of the license plate information association process. FIG. 13 is a flowchart showing the flow of the license plate information matching process. FIG. 14 is a diagram illustrating an overview of the license plate information acquisition apparatus according to the second embodiment. FIG. 15 is a block diagram illustrating the configuration of the license plate information acquisition apparatus according to the second embodiment. FIG. 16 is a flowchart illustrating the flow of the license plate information association processing according to the second embodiment. FIG. 17 is a diagram illustrating an overview of the license plate information acquisition apparatus according to the third embodiment. FIG. 18 is a diagram illustrating a computer that executes a license plate information acquisition program. FIG. 19 is a diagram for explaining a conventional license plate information association processing technique.

Explanation of symbols

1 pillar 2 vehicle 3 forward point 4 backward point 5 pillar 6 first lane forward point 7 first lane backward point 8 second lane forward point 9 second lane backward point 10 license plate information acquisition device 20 front license plate information generation device 21 Front camera 22 Front image temporary storage unit 23 Front license plate image storage unit 24 Front license plate information storage unit 25 Front vehicle detection processing unit 26 Front license plate recognition unit 27 Front license plate information reading unit 30 Rear license plate information generating device 31 Rear camera 32 Rear image temporary storage unit 33 Rear license plate image storage unit 34 Rear license plate information storage unit 35 Rear vehicle detection processing unit 36 Rear license plate recognition unit 37 Rear license plate information reading unit 40 Vehicle Tracking device 41 Fisheye lens camera 4 Monitoring the image storage unit 43 vehicle tracking unit 44 vehicle identification information transmitting unit 50 license plate information matching device 51 front and rear license plate information storage unit 52 sends the correspondence processing section 53 matching unit 54 unit

Claims (11)

Obtaining the front license plate information displayed on the front license plate of the vehicle passing through the front point, and acquiring the rear license plate information displayed on the rear license plate of the vehicle passing through the rear point, A license plate information acquisition device that associates front license plate information and rear license plate information,
Vehicle identification information for uniquely identifying the vehicle is given to the vehicle until the vehicle that is about to pass the front point is detected and the detected vehicle passes from the front point to the rear point. Vehicle tracking means for maintaining the state and tracking the vehicle;
The vehicle identification information given by the vehicle tracking means is acquired for the vehicle from which the front license plate information is acquired, and the front license plate information and the vehicle identification information acquired from the vehicle are stored in association with each other. Front information holding means,
A rear part that acquires vehicle identification information given by the vehicle tracking means to a vehicle from which the rear license plate information is acquired, and that associates and holds the rear license plate information and vehicle identification information acquired from the vehicle. Information holding means;
A front-rear association that associates the front license plate information and the rear license plate information to which the same vehicle identification information is assigned by comparing the vehicle identification information held in the front information holding means and the rear information holding means Means,
A license plate information acquisition apparatus comprising:   The vehicle tracking means detects a vehicle that is about to pass through the front point by processing an image obtained by imaging a region including the front point and the rear point, and sends the vehicle identification information to the vehicle. The license plate information acquiring apparatus according to claim 1, wherein the license plate information is tracked while maintaining the applied state.   The vehicle tracking means detects a vehicle passing through the front point by processing a reflected wave returned by an electromagnetic wave transmitted toward a region including the front point and the rear point, and the vehicle The license plate information acquisition apparatus according to claim 1, wherein the vehicle is tracked while maintaining a state in which the identification information is given to the vehicle.   The front number plate information for acquiring the front number plate information by imaging the front number plate of the vehicle passing through the front point on the pillar located between the front point and the rear point. It is installed together with an acquisition means and a rear license plate information acquisition means for capturing the rear license plate information by imaging the rear license plate of the vehicle passing through the rear spot, and detects a vehicle that is about to pass through the front spot. The license plate information acquisition apparatus according to claim 1, wherein the vehicle is tracked while maintaining a state in which the vehicle identification information is given to the vehicle.   The vehicle tracking means obtains the front number plate information by imaging a front number plate of a vehicle passing through the front point on a column located upstream or downstream from the front point and the rear point. Plate information acquisition means, and rear license plate information acquisition means for acquiring the rear license plate information by imaging the rear license plate of the vehicle passing through the rear spot, and trying to pass the front spot The license plate information acquisition apparatus according to claim 1, wherein the license plate information acquisition device according to claim 1, wherein the license plate information is tracked while detecting a vehicle and maintaining a state in which the vehicle identification information is given to the vehicle. The front license plate information and the rear license plate information are acquired for each lane in a plurality of lanes,
The vehicle tracking means detects a vehicle that is about to pass through the front point for each lane, and the vehicle identification information until the detected vehicle passes through a rear point of any lane from the front point. Keep track of the vehicle,
The front information holding means and the rear information holding means hold license plate information and vehicle identification information in association with each lane,
The front / rear association means compares the vehicle identification information of the same lane held in the front information holding means and the rear information holding means, and the front license plate information to which the same vehicle identification information is given and When there is rear license plate information, the front license plate information and rear license plate information are associated with each other, and when there is no front license plate information and rear license plate information to which the same vehicle identification information is given. The vehicle identification information of different lanes held in the front information holding means and the rear information holding means is compared, and the front license plate information and the rear license plate information to which the same vehicle identification information is assigned are associated with each other. The license plate information acquisition apparatus according to claim 1. Color shape information acquisition means for acquiring color information and shape information of the vehicle from which the front license plate information was acquired, and color information and shape information of the vehicle from which the rear license plate information was acquired, respectively.
The front information holding means and the rear information holding means hold the color information and shape information acquired by the color shape information acquisition means in association with the license plate information and vehicle identification information,
The front / rear association means compares the vehicle identification information, the color information and the shape information held in the front information holding means and the rear information holding means, and the same vehicle identification information, color information and shape information are The license plate information acquisition apparatus according to claim 1, wherein the assigned front license plate information and the rear license plate information are associated with each other. Time information indicating the time when the front license plate information was acquired, and time information acquisition means for acquiring time information indicating the time when the rear license plate information was acquired, respectively.
The front information holding means and the rear information holding means hold the time information acquired by the time information acquisition means in association with the license plate information and vehicle identification information,
The front / rear association means compares the vehicle identification information and time information held in the front information holding means and the rear information holding means, and is given the same vehicle identification information or adjacent time information. 2. The license plate information acquisition apparatus according to claim 1, wherein front license plate information and rear license plate information are associated with each other.   The apparatus further comprises collating means for comparing the front license plate information and the rear license plate information associated by the front / rear associating means to collate whether or not they belong to the same vehicle. The license plate information acquisition apparatus as described in any one of Claims 1-8. Obtaining the front license plate information displayed on the front license plate of the vehicle passing through the front point, and acquiring the rear license plate information displayed on the rear license plate of the vehicle passing through the rear point, A license plate information acquisition program that associates front license plate information and rear license plate information,
Vehicle identification information for uniquely identifying the vehicle is given to the vehicle until the vehicle that is about to pass the front point is detected and the detected vehicle passes from the front point to the rear point. A vehicle tracking procedure to keep track of the vehicle while maintaining state,
The vehicle identification information given by the vehicle tracking procedure is acquired for the vehicle from which the front license plate information is acquired, and the front license plate information and the vehicle identification information acquired from the vehicle are stored in association with each other. Front information retention procedure to
The rear part that acquires the vehicle identification information given by the vehicle tracking procedure for the vehicle from which the rear number plate information is acquired, and associates and holds the rear number plate information and the vehicle identification information acquired from the vehicle. Information retention procedures;
Front-rear association that compares the vehicle identification information held in the front information holding procedure and the rear information holding procedure and associates the front license plate information and the rear license plate information to which the same vehicle identification information is assigned. Procedure and
A license plate information acquisition program characterized by comprising: Obtaining the front license plate information displayed on the front license plate of the vehicle passing through the front point, and acquiring the rear license plate information displayed on the rear license plate of the vehicle passing through the rear point, A license plate information acquisition method for associating front license plate information and rear license plate information,
Vehicle identification information for uniquely identifying the vehicle is given to the vehicle until the vehicle that is about to pass the front point is detected and the detected vehicle passes from the front point to the rear point. A vehicle tracking process for tracking the vehicle while maintaining the state;
The vehicle identification information given by the vehicle tracking process is acquired for the vehicle from which the front license plate information is acquired, and the front license plate information and the vehicle identification information acquired from the vehicle are associated and held. Front information holding step to perform,
A rear part that acquires vehicle identification information given by the vehicle tracking step for a vehicle from which the rear license plate information is acquired, and associates and holds the rear license plate information and the vehicle identification information acquired from the vehicle. Information retention process;
A front-rear association that compares the vehicle identification information held in the front information holding step and the rear information holding step and associates the front license plate information and the rear license plate information to which the same vehicle identification information is assigned. Process,
The license plate information acquisition method characterized by including.

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