METHODS FOR IDENTIFYING A VEHICLE FROM CAPTURED IMAGE DATA

• US 20160379487A1
• Filed: 06/22/2016
• Published: 12/29/2016
• Est. Priority Date: 06/23/2015
• Status: Active Grant

• Current Assignee: Hunter Engineering Company
• Original Assignee: Hunter Engineering Company
• Inventors: Voeller, David A., Heine, William D., Klarer, John D.
• Granted Patent: US 9,990,376 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/51 Indexing; Data structures therefor; Storage structures
• CPC Class Codes: G06F 16/583 using metadata automatically derived from the content
• CPC Class Codes: G06V 10/245 by locating a pattern; Special marks for positioning
• CPC Class Codes: G06V 20/48 Matching video sequences
• CPC Class Codes: G06V 20/584 of vehicle lights or traffic lights
• CPC Class Codes: G06V 20/625 License plates
• CPC Class Codes: G08G 1/0175 by photographing vehicles, e.g. when violating traffic rules
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/80 Camera processing pipelines; Components thereof
• CPC Class Codes: H04N 23/90 Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums

Abstract

An imaging sensor observes a field of view through which a vehicle passes, at an orientation and position suitable for acquisition of license plate data from a surface of the vehicle. Responsive to the vehicle position, at least one image of a surface of the vehicle including a license plate is acquired and evaluated to extract license plate data. The position of the vehicle for acquisition of the image is established by a trigger in a fixed relationship with the imaging sensor.

Claims

1. A vehicle identification process for use with a vehicle service system, comprising:

monitoring an observation area through which a vehicle will pass to detect the presence of said vehicle;

responsive to a detection of said vehicle within said monitored observation area, acquiring at least one image of a surface of the vehicle on which a license plate is expected;

processing said at least one acquired image to detect the presence of a license plate on the vehicle and to extract identifying data from said image, said identifying data associated with said detected license plate; and

associating said extracted identifying data with at least one item of vehicle-specific data.

2. The vehicle identification process of claim 1 wherein said at least one item of vehicle-specific data is retrieved from a database.

3. The vehicle identification process of claim 1 wherein said at least one item of vehicle-specific data includes at least one of a vehicle identification number, a vehicle make, a vehicle model, a vehicle owner, a vehicle service history, a vehicle recall record, a recommended vehicle service, or vehicle inspection results.

4. The vehicle identification process of claim 1 wherein said at least one item of vehicle-specific data is an image of said vehicle.

5. The vehicle identification process of claim 1 wherein said step of monitoring includes

establishing an optical target feature within a field of view encompassing said monitored observation area, said optical target feature established in a fixed position which is obscured by the passage of a vehicle through said monitored observation area;

acquiring a sequence of images of said field of view; and

evaluating each of said images to detect a presence or an absence of said optical target feature within each of said images.

6. The method of claim 1 wherein said step of monitoring includes receiving a signal from a vehicle measurement system, said signal indicating the presence of said vehicle at a known location relative to said observation area.

7. The method of claim 6 wherein said signal is either a trigger signal associated with the presence of said vehicle or a data associated with a measurement acquired from said vehicle by said vehicle measurement system.

8. The vehicle identification process of claim 1 wherein said step of monitoring includes

acquiring measurements representative of a distance to a surface within said monitored observation area, said distance measurements acquired along a measurement axis which is intersected by the presence of a vehicle within said monitored observation area, whereby said measured distance is decreased when said vehicle is present, indicating a detection of said vehicle.

9. The vehicle identification process of claim 8 wherein said measurement axis is parallel to an optical axis of said imaging system.

10. The vehicle identification process of claim 8 wherein said measurements representative of distance are acquired acoustically.

11. The vehicle identification process of claim 1 wherein said step of monitoring includes

selecting an image frame from a set of images of said observation area sequentially captured by an imaging sensor, comprising:

evaluating a region within each of said captured images to identify either the presence or absence of an observed target feature; and

selecting for image processing, at least one captured image in said set of images based on a change in the identified presence or absence of said observed target feature between a pair of sequentially captured images.

12. The method of claim 11 wherein said target feature is stationary within said observation area, and wherein said observation area is fixed.

13. The method of claim 11 wherein said step of evaluating includes selectively processing only said region of each captured image to identify the presence or absence of said target feature, said region of each captured image associated with a set of image pixels which are optically aligned with the expected location of said target feature in said observation area.

14. The method of claim 11 wherein said imaging sensor is associated with a vehicle inspection system, and wherein said target feature is temporarily obscured from said imaging sensor by the presence of a vehicle within said observation area.

15. The method of claim 14 wherein said target feature is located such that either a rear surface of said vehicle is present within said observation when visibility of said target feature is initially restored to said imaging sensor by movement of said vehicle;

or

a front surface of said vehicle is present within said observation area when visibility of said target feature is initially blocked from said imaging sensor by movement of said vehicle.

16. The method of claim 15 wherein said processing of said selected image identifies license plate data associated with said vehicle;

and

further including the step of utilizing said license plate data to associate at least one identifying item with said vehicle.

17. The method of claim 16 wherein said at least one identifying item includes at least one of a vehicle identification number, a vehicle photograph, a vehicle make, a vehicle model, a vehicle owner, a vehicle service history, a vehicle recall record, a recommended vehicle service, or vehicle inspection results.

18. A vehicle identification method for use with a vehicle inspection system, comprising:

monitoring an observation area through which a vehicle undergoing inspection will pass to detect a presence of said vehicle;

responsive to subsequent detection of said vehicle within said monitored observation area, acquiring at least one image of a surface of said vehicle on which a license plate is present;

processing said at least one acquired image to extract identifying license plate data; and

associating said extracted identifying license plate data with at least one item of vehicle-specific data.

19. The method of claim 18 wherein said step of associating said extracted identifying license plate data includes retrieving said at least one item of vehicle-specific data from a database of vehicle-specific data indexed by said identifying license plate data.

20. The method of claim 19 wherein said at least one item of vehicle-specific data is a vehicle identification number.

21. The method of claim 19 wherein said database is a remote database, and wherein said identifying license plate data and said at least one item of vehicle-specific data are conveyed over a communications network between said vehicle inspection system and said remote database.

22. The method of claim 18 wherein said at least one item of vehicle-specific data is said acquired image.

23. The method of claim 18 wherein said step of monitoring includes:

establishing an optical target feature within a field of view encompassing said monitored observation area, said optical target feature established in a fixed position which is obscured by a passage of said vehicle through said monitored observation area;

acquiring a sequence of images of said field of view;

evaluating each of said images to detect a presence or an absence of said optical target feature within each of said images; and

detecting a departure of said vehicle in response to an observed presence of said optical target feature in an image occurring subsequent to an observed absence of said optical target feature in a preceding image.

24. The method of claim 18 wherein said step of monitoring includes:

acquiring measurements, each representative of a distance to a surface within said monitored area, each of said measurements acquired along an common axis intersected by a passage of said vehicle through said monitored area, whereby said vehicle is detected in response to said measurements decreasing during said passage of said vehicle; and

responsive to said measurements returning to a baseline distance following a detected passage of said vehicle, indicating said departure of said detected vehicle from said monitored area.

25. The method of claim 18 wherein said step of monitoring includes receiving a signal from a vehicle measurement system, said signal indicating the presence of a vehicle at a known location relative to said observation area.

26. The method of claim 25 wherein said signal is either a trigger signal associated with the presence of said vehicle or a data associated with a measurement acquired from said vehicle by said vehicle measurement system.

27. The method of claim 25 wherein said vehicle measurement system is one of a drive-over tire tread depth measurement system, a drive-over brake test system, a vehicle weight scale, a vehicle body condition recording system, or a vehicle wheel alignment measurement system.

28. A vehicle detection system configured to automatically identify a vehicle present in a vehicle service area, comprising:

an imaging system responsive to the presence of a vehicle within said vehicle service area to acquiring at least one image of a vehicle surface;

a processing system configured to receive said acquired images from said imaging system, said processing system further configured to evaluate said acquired images to detect the presence of a license plate on the vehicle surface and to extract identifying data associated with said detected license plate from said image; and

wherein said processing system is further configured to associate said extracted identifying data with at least one item of vehicle specific data.

29. The vehicle detection system of claim 28 wherein said processing system is further configured to receive a signal from a vehicle measurement system, said signal indicating the presence of a vehicle within said vehicle service area;

and

wherein said processing system is configured to signal said imaging system to acquire said at least one image of a vehicle surface in response to said signal from said vehicle measurement system.

30. The vehicle detection system of claim 29 wherein said vehicle measurement system is one of a drive-over tire tread depth measurement system, a drive-over brake test system, a vehicle weight scale, a vehicle body condition recording system, or a vehicle wheel alignment measurement system.

31. The vehicle detection system of claim 28 wherein said at least one item of vehicle specific data is stored in a remote database in association with vehicle license plate data;

and

wherein said processing system is configured to communicate said extracted identifying data to said remote database to retrieve said at least one item of vehicle specific data.

32. The vehicle detection system of claim 28 wherein said item of vehicle specific data includes at least one of a vehicle identification number, a vehicle photograph, a vehicle make, a vehicle model, a vehicle owner, a vehicle service history, a vehicle recall record, a recommended vehicle service, or a vehicle inspection result.