JP2008152627A - Vehicle color discrimination system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle color discrimination system that can provide an almost 100% accuracy rate with the use of a vehicle color discrimination apparatus having an insufficient accuracy rate. <P>SOLUTION: The vehicle color discrimination system comprises: a roadside apparatus 2 comprising a color camera 1 for imaging a vehicle running on a road, and an image processing part 22 having a license plate recognition part 221 for reading license plate information from the image captured by the color camera and a vehicle color discrimination part 222 for discriminating the color of the vehicle from the image captured by the color camera; and a central apparatus 1 having a vehicle color discrimination result verification part 112 for receiving the discrimination result determined by the vehicle color discrimination part and determining the validity of the received discrimination result, and a storage part 13 recording correspondences between vehicle license plate information and vehicle colors. The vehicle color discrimination result verification part determines the validity of the vehicle color discriminated by the vehicle color discrimination part by matching the vehicle color discriminated by the vehicle color discrimination part against the vehicle color retrieved from the storage part on the license plate information identified by the license plate recognition part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle color discrimination system, and more particularly to a vehicle color discrimination system that can improve accuracy at a low cost.

  Search and identify traveling vehicles by taking pictures of the traveling vehicles and monitoring the captured images to be used for road traffic monitoring, traffic surveys, search for specific vehicles, or business marketing. The technology to do is known. In such a vehicle search technology, the color information of the characteristic part of the vehicle is useful information for specifying the vehicle.

In Patent Document 1, a license plate of a vehicle is detected from a color image obtained by photographing the vehicle, a position coordinate of the detected license plate is set, and a vehicle body color is set in a region of a relative position predetermined from the set position coordinate. A vehicle color discrimination device that sets a discrimination area 31 and discriminates the color of the set area as a car color is disclosed.
JP 2006-201817 A

 However, the accuracy rate (83.5%) of the discrimination result of the vehicle color discrimination device disclosed in Patent Document 1 is not a sufficient value. As described above, the color information of the characteristic part of the vehicle is used for searching for the vehicle, and the accuracy rate is preferably 100%. However, cameras for photographing vehicles are often installed outdoors and are affected by sunlight. Also, it is difficult to set the correct answer rate to 100% due to the influence of the correct answer value (color) varying depending on the subjectivity of the person to be judged.

  The present invention has been made in view of these problems, and provides a vehicle color discrimination system that can obtain a value that is close to 100% even when a vehicle color discrimination device with an insufficient accuracy rate is used. Is.

  In order to solve the above problems, the present invention employs the following means.

  A color camera that captures a vehicle traveling on the road, a license plate recognition unit that reads number plate information based on an image captured by the color camera, and a vehicle color of the vehicle based on an image captured by the color camera. A road device provided with an image processing unit having a vehicle color discrimination unit to discriminate, a vehicle color discrimination result confirmation unit that receives a discrimination result discriminated by the vehicle color discrimination unit, and judges the validity of the received discrimination result; A central unit having a storage unit that records the correspondence between the license plate information of the vehicle and the vehicle color, and the vehicle color determination result confirmation unit includes the vehicle color determined by the vehicle color determination unit and the license plate recognition unit The vehicle color obtained by searching the storage unit based on the license plate information identified by the vehicle is checked to determine the validity of the vehicle color determined by the vehicle color determination unit.

  Since the present invention has the above-described configuration, it is possible to provide a vehicle color discrimination system that can obtain a value with a correct answer rate close to 100% using a vehicle color discriminator with an insufficient accuracy rate.

  Hereinafter, the best embodiment will be described with reference to the accompanying drawings. FIG. 1 is a diagram for explaining the configuration of a vehicle color discrimination system according to an embodiment of the present invention.

  In FIG. 1, the vehicle color discrimination system includes a central device 1 and a plurality of road devices 2-1 to 2-N. Data transmission / reception between the central device 1 and the plurality of road devices 2-1 to 2-N is performed via the wide area network 3.

  Each of the plurality of road devices 2-1 to 2-N includes an imaging unit 21 and an image processing unit 22. The imaging unit 21 includes a color camera 211. The image processing unit 22 includes a license plate recognition unit 221, a car. A color determination unit 222 and a vehicle information transmission unit 222 are provided.

  The license plate recognition unit 221 monitors a vehicle traveling on the road through the color camera 211, detects that the vehicle has entered the field of view of the color camera 211 for reading the license plate, and reads the license plate information. Note that the reading (recognition) and reading time (vehicle detection time) of the license plate information can be performed relatively easily by an already known image recognition method.

  The read license plate information and the vehicle detection time are transmitted to the vehicle color determination unit 222 and the vehicle information transmission unit 223.

  The vehicle color discrimination group 222 AD-converts the image transmitted from the color camera 211 and stores it in an internal memory installed in the image processing unit 22. Further, when the vehicle color determination unit 222 receives the vehicle detection time from the license plate recognition unit 221, the vehicle color determination unit 222 extracts a color image transmitted from the color camera 211 at that time and determines the vehicle color. The discrimination of the vehicle color can be performed relatively easily by an already known image recognition method.

  Then, the vehicle color determination unit 222 transmits the determined vehicle color and detection time information to the vehicle information transmission city 223. The vehicle information transmission unit 223 transmits the license plate information, vehicle detection time information, vehicle color information, and detected point information on the road (information on the point where the road device is arranged) to the central device 1 via the wide area network 3. To do.

  The central device 1 includes a vehicle color determination unit 11, a vehicle search unit 12 that searches for a specific vehicle, and a storage unit 13. The vehicle color determination unit 11 includes a vehicle information reception unit 111 and a single color determination result confirmation unit 112.

  The vehicle information receiving unit 111 receives the license plate information, vehicle detection time information, vehicle color information, and road point information transmitted by the road devices 2-1 to 2-N, and stores the received information in the storage unit 13. At the same time, it is transmitted to the vehicle color discrimination result confirmation unit 112.

  As will be described later, the vehicle color discrimination result confirmation unit 112 determines whether the received data is valid, and corrects the data stored in the storage unit 13 when it is not valid.

  The vehicle search unit 12 includes a vehicle information search unit 121 and a search result display unit 122. The vehicle information search unit 121 searches the license plate information or vehicle color information of the vehicle stored in the storage unit 13 to extract and specify the vehicle that matches the specific vehicle information, the position information of the specified vehicle, etc. Is transmitted to the result display unit 122. The result display unit 122 displays the position information and the like transmitted from the vehicle information search unit 121 on the display.

  FIG. 2 is a diagram illustrating an example in which a vehicle color discrimination unit is provided on the central device side. As shown in FIG. 2, the road device 2 transmits the image captured by the color camera 221 to the vehicle information transmission unit 223 at the timing when the license plate recognition unit 221 detects the vehicle, and the vehicle information transmission unit 223 receives the image. The video is transmitted to the central apparatus 1 via the wide area network 3.

  The vehicle information receiving unit 111 of the central device 1 receives the license plate information, vehicle detection time information, road point information, and color camera image transmitted by the road devices 2-1 to 2-N, and stores the received information as the storage unit 13. And transmitted to the vehicle color discrimination unit 113. The vehicle color discrimination unit 113 discriminates the vehicle color, stores the result in the storage unit 13, and transmits the result to the vehicle color discrimination result confirmation unit 112.

  FIG. 3 is a diagram for explaining a processing example of the vehicle color discrimination result confirmation unit. First, the license plate information and the vehicle color discrimination result are received from the vehicle information receiving unit 111. Here, as an example, it is assumed that the received license plate information is “Hitachi 11 1234” and the vehicle color discrimination result is “red” (step S101).

  Next, based on the received license plate information, the storage unit 13 is accessed, and the vehicle information stored when the vehicle color determined is determined in the past is searched. The license plate information at this time must be unique. Further, the search period is specified in a short period such as one day, and is repeated until the number of extracted search results is, for example, five or more. However, the search process ends when the search period exceeds, for example, one week. FIG. 4 shows an example of the search result (step S102).

  Next, the validity of the vehicle color discrimination result is confirmed from the search result. In this example, the vehicle color discrimination result is “red” as described above. However, when looking at past traffic histories of vehicles having the same license plate information, the vehicle color of the vehicle having “Hitachi 11 1234” is stored as “gray”. For this reason, it determines with the said vehicle color discrimination | determination result not being appropriate (step S103, 104).

  Next, according to the determination result of step S104, the determination result is corrected to “gray”, and the corrected determination result is stored in the storage unit 13.

  FIG. 5 is a diagram illustrating an example in which a plurality of vehicle color discrimination results (first candidate and second candidate in the example in the figure) are stored in the storage unit. For example, the first candidate of the vehicle color discrimination result of a vehicle having license plate information of “Hitachi 11a 1234” is “red” and the second candidate is “gray”, and the storage unit is stored based on the license plate information. Assume that the search result is as shown in FIG. Here, the first candidate indicates a color determined to be most likely (highly valid) by the vehicle color determination unit 222 or 113, and the second candidate indicates a color having the second highest validity.

  In the case of this example, in the determination of step S103, the first candidate is determined to be “ash” based on the majority rule, and the second candidate is corrected in the first candidate. Is determined.

  FIG. 6 is a diagram illustrating an example in which a color camera and a near-infrared camera (or an ultraviolet camera) are provided in the imaging unit. In FIG. 6, the near-infrared camera 212 can read license plate information stably even at night. Since the color camera 211 cannot secure the brightness required for vehicle color determination at night, the single color determination unit 222 cannot correctly determine the vehicle color.

  For this reason, the vehicle color determination unit 222 sets the vehicle color determination result to “unknown” at night. The vehicle color discrimination result is transmitted to the central apparatus 1 via the vehicle information transmission unit 223 and the wide area network 3 as described above. In this case, the central device 1 determines the vehicle color according to the example of FIG.

  7 and 8 are diagrams for explaining correction processing of information stored in the storage unit of the central device. 7 and 8, the vehicle information receiving unit 111 receives the license plate information, vehicle detection time information, vehicle color information, and point information on the road transmitted by the road devices 2-1 to 2-N, and receives the received information. While storing in the memory | storage part 13, it transmits to the vehicle color discrimination | determination result confirmation part 112 (step S201).

  The vehicle color discrimination result confirmation unit 112 searches for previously acquired vehicle information based on the received license plate information. Here, as an example, it is assumed that the received license plate information “Hitachi 11 1234” and the vehicle color discrimination result is “red”. Therefore, in this example, the storage unit 13 is searched to extract a vehicle whose license plate information is “Hitachi 11a 1234” (step S202).

  Next, the extracted vehicle color discrimination result of the vehicle is compared with the received vehicle color discrimination result (step S203). As an example, the extracted vehicle color discrimination result of the vehicle is “yellow”. Since the received vehicle color discrimination result is “red” as described above, it can be seen that it is different from the vehicle color discrimination result “yellow” performed in the past. As described above, when the vehicle color discrimination result performed in the past is different from the received vehicle color discrimination result, the vehicle information search unit 121 is notified that the vehicle color discrimination result is different (steps S204 and 205). ).

  When the vehicle information search unit 121 receives a notification that the vehicle determination results are different, the vehicle information search unit 121 pops up a message indicating that the vehicle color determination result is abnormal on the search result display unit 122.

  The reason for the difference between the past car color discrimination result and the received car color discrimination result (current car color discrimination result) is that there is an error in the past or current car color discrimination result, or there is an error in the license plate recognition result. There is one of them.

  Therefore, for example, when a pop-up display indicating the abnormality is made on the search result display unit 122, a list of vehicles that are considered to be the same as the vehicle whose vehicle color has been determined in the past is displayed. The list of vehicles is assembled with the color camera image. Thus, the user can determine which is the correct vehicle color discrimination result by referring to the list of vehicles. Further, the user can rewrite the list to a correct result.

  As described above, according to the embodiment of the present invention, the current vehicle color discrimination result is compared with the past vehicle color discrimination result, and the current vehicle color discrimination result is corrected automatically or manually according to the comparison result. can do. Thereby, the correct answer rate of a vehicle color discrimination | determination result can be improved. According to this method, for example, when many road devices are installed, the correct rate of the license plate reading result is 95% (actual operation result value), and the correct rate of the vehicle color discrimination is 83.5%, The accuracy rate of the color discrimination result can be increased to 98.9%. It should be noted that the worst value is a correct answer rate of about 95%, which is the same as when the answer is incorrect due to an error in the license plate reading result.

  Thus, due to an incorrect answer of the license plate reading result or the like, there is a possibility that the vehicle color determination result is erroneously determined to be incorrect even though the vehicle color determination result is originally correct. Therefore, a method for storing a plurality of vehicle color discrimination results (first candidate and second candidate) as shown in FIG. 5 in a storage unit or a method including a vehicle color discrimination result confirmation unit as shown in FIG. This is effective for improving the vehicle color discrimination result.

  In addition, according to the embodiment of the present invention, (1) a vehicle is photographed as needed, and license plate information and vehicle color information of a characteristic part are recognized from the photographed image. (2) At this time, based on the license plate reading result, the past passing vehicle data (vehicle data to be read) is retrieved from the storage device, and the validity of the vehicle color discrimination result is confirmed.

  Considering the use as a vehicle color discriminating means capable of obtaining a correct answer rate of 80% or more, it is desirable to confirm the validity by using the discrimination results of the past five times. Further, as described above, when the current vehicle color discrimination result is clearly different from the past vehicle color discrimination result, the vehicle color discrimination result is corrected and registered in the storage device. As a result, even if the vehicle color is misclassified due to some factor, the misclassification result is automatically corrected, and the correct answer rate can be close to 100%.

  Further, in the above (1), a plurality (two) of vehicle color discrimination result candidates are output, and when the car color of the characteristic part is discriminated, the candidate with the highest validity is the first candidate and the second validity. When the candidate with a high value is defined as the second candidate, the result of searching past passing vehicle data and the majority rule are used for determination, and the determination result is determined as the first candidate and the first candidate before determination using the majority rule. As a second candidate, it is stored in the storage device. As a result, although the vehicle color is correctly recognized, data can be retained by the second candidate even if the vehicle color is erroneously corrected.

  In addition, when the vehicle color cannot be determined at night, the past passing vehicle data is applied as the vehicle color information of the vehicle that has passed. Thereby, vehicle color information with a high accuracy rate can be added even at night.

  In addition, when manually searching for a storage device that accumulates vehicle information, the validity of the vehicle color discrimination result is confirmed and erroneous data is corrected. Thereby, it is possible to reduce the load on the device that occurs every time the vehicle information recognition result is accumulated in the storage device.

It is a figure explaining the composition of the car color discriminating system concerning the embodiment of the present invention. It is a figure explaining the example provided with the vehicle color discrimination | determination part at the central apparatus side. It is a figure explaining the process of a vehicle color discrimination | determination result confirmation part. It is a figure which shows the example of a search result. It is a figure explaining the example which memorize | stores several vehicle color discrimination | determination result in a memory | storage part. It is a figure explaining the example provided with a color camera and a near-infrared camera in an imaging part. It is a figure explaining the correction process of the information memorize | stored in the memory | storage part of the central apparatus. It is a figure explaining the correction process of the information memorize | stored in the memory | storage part of the central apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Central apparatus 2 Road apparatus 11 Car color discrimination | determination part 12 Vehicle search part 13 Memory | storage part 21 Image pick-up part 22 Image processing part 111 Vehicle information reception part 112 Car color discrimination | determination result confirmation part 113 Car color discrimination | determination part 121 Vehicle information search part 122 Search result Display unit 211 Color camera 212 Near-infrared camera 221 Number plate recognition unit 222 Car color determination unit 223 Vehicle information transmission unit

Claims (5)

A color camera that captures a vehicle traveling on the road, a license plate recognition unit that reads number plate information based on an image captured by the color camera, and a vehicle color of the vehicle based on an image captured by the color camera. A road device including an image processing unit having a vehicle color discrimination unit for discrimination;
A vehicle color discrimination result confirmation unit that receives a discrimination result discriminated by the vehicle color discrimination unit and determines the validity of the received discrimination result, and a storage unit that records a correspondence relationship between vehicle license plate information and vehicle color With a central device,
The vehicle color discrimination result confirmation unit compares the vehicle color identified by the vehicle color discrimination unit with the vehicle color obtained by searching the storage unit based on the license plate information identified by the license plate recognition unit. And determining the validity of the vehicle color determined by the vehicle color determination unit. A road camera having a color camera for shooting a vehicle traveling on the road, and an image processing unit having a license plate recognition unit for reading number plate information based on an image shot by the color camera;
A vehicle color discrimination unit that discriminates the vehicle color of the vehicle based on an image photographed by the color camera, a vehicle color discrimination result confirmation unit that judges the validity of the discrimination result discriminated by the vehicle color discrimination unit, and a vehicle A central device having a storage unit that records the correspondence between license plate information and car color,
The vehicle color discrimination result confirmation unit compares the vehicle color determined by the vehicle color discrimination unit with the vehicle color obtained by searching the storage unit based on the license plate information identified by the license plate recognition unit. Then, the vehicle color discrimination system characterized by determining the validity of the vehicle color determined by the vehicle color determination unit. A color camera that captures a vehicle traveling on the road, a license plate recognition unit that reads number plate information based on an image captured by an infrared or ultraviolet camera, and a vehicle of the vehicle based on an image captured by the color camera A road device including an image processing unit having a vehicle color determination unit for determining a color;
A vehicle color discrimination result confirmation unit that receives the discrimination result discriminated by the vehicle color discrimination unit and determines the validity of the received discrimination result, and a storage unit that records the correspondence between vehicle license plate information and vehicle color With a central device,
The vehicle color determination result confirmation unit compares the vehicle color determined by the vehicle color determination unit with the vehicle color obtained by searching the storage unit based on the license plate information identified by the license plate recognition unit. And determining the validity of the vehicle color determined by the vehicle color determination unit. A road camera having a color camera for shooting a vehicle traveling on the road, and an image processing unit having a license plate recognition unit for reading number plate information based on an image shot by an infrared or ultraviolet camera;
A vehicle color discrimination unit that discriminates the vehicle color of the vehicle based on an image photographed by the color camera, a vehicle color discrimination result confirmation unit that judges the validity of the discrimination result discriminated by the vehicle color discrimination unit, and a vehicle A central device having a storage unit that records the correspondence between license plate information and car color,
The vehicle color discrimination result confirmation unit compares the vehicle color determined by the vehicle color discrimination unit with the vehicle color obtained by searching the storage unit based on the license plate information identified by the license plate recognition unit. Then, the vehicle color discrimination system characterized by determining the validity of the vehicle color determined by the vehicle color determination unit. The color discrimination system according to claim 1,
The vehicle color discrimination result confirmation unit registers a plurality of vehicle color candidates in a storage device in descending order of validity, and performs majority processing of a plurality of discrimination results for the same vehicle in the past, and When the majority processing results are different, the majority processing result is determined as the most appropriate vehicle color, the most appropriate vehicle color candidate is determined as the second most appropriate vehicle color, and the determination result is stored. A vehicle color discrimination system which is registered in a device.

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