Field of the Invention The invention relates broadly to a traffic violation processing system. In one or more specific embodiments, the invention is directed to a method of recording and storing digitized vehicle images and textual information e. Description of Related Art Traffic monitoring systems have been used for a number of years to identify vehicles violating various traffic regulations, ranging from exceeding the speed limit to running red lights or stop signs. Some of these traffic monitoring systems include cameras configured to take a photographic image of the violators.
Sometimes, the traffic monitoring systems are located in a monitoring vehicle, e. In other cases, the systems are not located in a vehicle, but rather are stationary, positioned close to the roadway, e.
Sometimes, the systems are controlled by an operator who is present during monitoring. The systems may also be operated automatically, without an operator being present. In either case, the images captured by the camera on film are typically stored in a film magazine. The photographic images recorded on film by the camera are often used to form evidentiary records for purposes of proving the existence of a violation. One of the shortcomings associated with storing images on film is that the number of images that can be stored tends to be limited by the space in the film magazine.
The system's ability to record violations is thus limited by the capacity of the film magazine. When the film magazine reaches its maximum capacity, the system can no longer record images of violators. Because it is often difficult if not impossible to accurately estimate the number of violators at a given location, it is also difficult to determine when the capacity of the film magazine has been reached. Another shortcoming of these earlier systems is that the operator must often make frequent trips to a central processing location to deliver the film for developing and processing.
The need to make such frequent trips can occupy a great deal of time. The expenditure of time is magnified when numerous traffic monitoring systems are located in different geographic locations at inconvenient distances from central processing location. Yet another shortcoming of the earlier systems is the labor-intensive process of matching the vehicle in each photographic image with registered owner information, in order to prepare traffic citations or an evidentiary record.
For example, after the image is developed, the photograph is examined by a person to identify the license plate number. Next, the license plate number is correlated with a listing of registered vehicle owners to determine the name of the owner, after which the traffic citation is prepared. This is done typically by manually inputting information relating to the traffic violation, then mailing the traffic citation to the registered owner.
This cumbersome process is inefficient and results in high costs and expenditures of time. A continuing need therefore exists for a traffic violation processing system that overcomes one or more of the abovementioned shortcomings.
SUMMARY OF INVENTION In a broad aspect, this invention is directed to a traffic violation processing method, which preferably includes the steps of monitoring a vehicle; determining whether the vehicle is in violation of a traffic violation; recording a digital traffic image comprising the digital image of the vehicle; recording alphanumeric traffic data corresponding to the vehicle; storing the digital traffic image and the alphanumeric traffic data on a storage media; matching the alphanumeric traffic data with registered owner information from a database which identifies the vehicle's registered owner; and providing a traffic document comprising the traffic violation, the identity of the registered owner, and the digital traffic image.
In a preferred embodiment, the method includes the steps of assigning an image control number ICN or other identifier to a traffic image frame, wherein the ICN or identifier is associated with a specific traffic violation; transferring a set of deployment data which includes the ICN or identifier as well as other information regarding the traffic violation to storage media.
Preferably, the deployment data are stored on a portable diskette. The method then involves combining a digitized version of the traffic image with the ICN or identifier; storing the digitized image together with the ICN or identifier on a database; matching the deployment data with the stored digital image by correlating or matching the ICN or identifier associated with the deployment data with the ICN or identifier associated with the stored digital image; and generating a traffic document that includes the stored digital image and the deployment data.
Preferably, the method also includes processing the digitized trafffic image by reducing the resolution of the image and extracting an LPA image from the digitized traffic image by removing or clipping a portion of the digitized traffic image to provide the LPA. The method also includes preferably includes the steps of reading a license plate number from the digitized image or the LPA using optical character recognition OCR ; storing the license plate number along with the ICN from the image in a database, preferably the same database on which the traffic image is stored; and matching the license plate number with the stored image and the deployment data using the ICN.
Preferably, the license plate number recovered from the image using OCR is matched with the license plate number recovered from a registered vehicle owner database; and a traffic document is generated, containing the digital traffic image, the deployment data, and the license plate number, along with other information regarding the vehicle owner and the nature of the violation. The steps or operations discussed below refer to the storage of the image and text for one image frame.
Each frame may be processed in the same manner. Also, the invention may be utilized with any number of traffic monitoring systems or traffic cameras, and is not directed to any particular one. One aspect of the invention relates to traffic image processing and storage, specifically, the processing of images containing vehicles being monitored for compliance with traffic regulations.
Another aspect of the invention relates to traffic data processing and storage. Before processing, the image must be in digital form. Preferably, the digital images are black and white images, i. High resolution images are desirable for purposes of optical character recognition. Any one of the aforementioned traffic images may also be reduced in resolution as discussed in greater detail below to provide a low resolution traffic image or low resolution scene LRS image.
The various images are exemplified in FIG. The term "traffic scene image" 16 refers to the image of the entire scene captured by the camera. The "vehicle image" 18 is actually a sub-image, i. The "non-vehicle image" 19 is another sub-image, i. The "LPA image" 20 is the sub-image portion of the vehicle image containing the license plate or license tag.
The LPA image may occupy a portion of the vehicle image, e. A variety of devices for capturing traffic images may be used, and the particular device used for image capture is beyond the scope of the invention. For example a traffic image may be recorded on photographic film, e. Traffic monitoring systems with cameras are generally well-known.
Specific embodiments of traffic monitoring systems that include a film-based camera are disclosed in co-pending applications, Ser. Other specific embodiments of traffic monitoring systems that may be used with this invention are described in U. Alternatively, a digitized or digital traffic image may be recorded directly using a digital camera.
Such a digital image could be stored, for example, in a charged-couple device CCD digital storage unit. In general, methods for capturing digital images using CCD-based cameras are known, including those disclosed in U.
Photographic images from color or black and white film may be scanned using the scanner, converted from a negative to a positive image if desired, then directed to the image processing system for further treatment. The deployment data, discussed below, may also be placed on the film or on the digitized image. Any commercially available scanner may be utilized for these purposes. Preferably, a high resolution high quality image is formed, e. The term "traffic data" as used herein refers broadly to any alphanumeric or textual information related to the traffic situation being monitored, including both location information and vehicle information.
The traffic data may be stored on a data diskette in textual form, or on some other conventional data storage means. The traffic data may be stored simultaneously with the capturing of the traffic scene image. Each "violation record" or "offense record" may include both a traffic image and corresponding alphanumeric traffic data, and may be stored as a separate record in the database. Preferably, one set of traffic data is recovered from the captured image using the OCR step, while another set of traffic data, referred to herein as "deployment data," is recovered from traffic monitoring system.
The deployment data includes certain violation information that is recordable by the traffic monitoring system. The deployment data may include, for example, an image contral number ICN , the measured vehicle speed, applicable speed limits, the date and time of violation, traffic conditions e.
In a specific embodiment, the method includes the step of attaching an identifier to a traffic image, e. The method also includes the steps of transferring a set of deployment data which includes the identifier to a storage medium, preferably a diskette; storing a digitized version of the traffic image together with the identifier on a database; matching the deployment data with the stored digital image by matching the identifier associated with the deployment data with the identifier associated with the stored digital image; and generating a traffic document that includes the stored digital image and the deployment data.
As used herein, the term "low resolution image" is a relative term which refers to any traffic image after its original resolution has been reduced. Preferably, the resolution of one or more of the digitized images e. Preferably, the LPA image is taken from the original high resolution and stored separately, and any remaining images that are to be stored are reduced in resolution prior to being stored. Advantageously, this resolution reduction step reduces the digital storage requirements for that image.
Such resolution reduction may be accomplished in a number of ways. Resolution reduction is preferably accomplished using digital compression, i. JPEG methods involve a standardized image compression mechanism, by which full-color or gray-scale images are compressed. Resolution reduction and compression in general are well-known, as suggested by U. One of the benefits of image reduction is that less storage space is required.
However, when that image is compressed at a ratio of about For a compression ratio of about 12 to 1, only about 96 kb would be needed and for a compression ratio of 15 to 1, only about After compression at the selected ratio, the image is preferably stored on the image server, although it may alternatively be stored in any conventional storage media.
That is, a selected portion of one or more of the aforementioned images may be extracted i. This extraction method may also be referred to as "clipping" or "cropping" the larger image to remove the imagery surrounding the image that is extracted.
For example, the vehicle image portion may be extracted from the larger traffic scene image; or the LPA image may extracted from the traffic scene image or the vehicle image; or the LPO image may be extracted from one of the other images. This extraction operation is preferably performed simultaneously with resolution reduction, i. That is, a traffic scene image or vehicle image is duplicated so that one copy may be reduced in resolution and stored; and another copy may be clipped to extract a high resolution LPA or LPO image.
In this manner, the portion of the traffic scene image for which high resolution is desired typically the LPA or LPO image is stored and processed separately from the low resolution portion. Typically, the low resolution image is the vehicle image or the entire traffic scene image. This clipping operation may be accomplished by removing selected scene information outside a pre-determined area, e.
In a specific embodiment, the LPA image is clipped using the size and position coordinates as found during optical recognition. This clipping further isolates the license plate image and reduces the necessary storage, for example, from 1. The compressed LPO image may then be stored, e. Advantageously, the production of the LPO image from the LPA image reduces the total file size yet maintains the initial alphanumeric characters and jurisdiction information in original high resolution.
Image extraction itself, including the clipping or cropping of portions of a digital image, is conventional and thus will not be described in detail. Optical character recognition OCR itself is conventional and thus will not be described in detail.
In accordance with this invention, OCR may be used to automatically obtain the plate owner information by accessing the database containing the registered owner data set and storing the result along with a digital traffic image. More particularly, after or during the clipping and resolution reduction operations, any one of the traffic images may be passed to an optical character recognition OCR system to convert various traffic data from the image to a form that can be stored in the database and matched with registered owner information.
The OCR system preferably also locates the exact size and position coordinates of the license plate from the LPA image, e. In accordance with a specific embodiment of the invention, if the OCR operation is successful, then the traffic data may be processed as described below. If, however, the OCR operation is unsuccessful, e. In a specific embodiment, the traffic data are used to locate the plate owner's information in a vehicle and customer database, preferably a registered owner database, e.
After being recognized by the OCR step, the license plate information and plate owner's information may be stored on the image server or some other storage media.