Patent Publication Number: US-6982654-B2

Title: Automated license plate recognition system for use in law enforcement vehicles

Description:
The present application is based on and claims the benefit of U.S. provisional patent application Ser. No. 60/426,235, filed Nov. 14, 2002, the content of which is hereby incorporated by reference in its entirety. 

   BACKGROUND OF THE INVENTION 
   The present invention is directed towards recovering stolen vehicles, and more particularly towards identifying a stolen vehicle in the public space. 
   Automobile theft is a leading cause of loss among the insurance industry, costing consumers more than $7.5 billion per year. The National Insurance Crime Bureau (NICB) reported in 2001 that an estimated 5 million vehicles are stolen worldwide each year. Approximately 1.2 million of those vehicles were stolen in the United States alone or one every 25 seconds. In other words one out of every 170 registered vehicles in the United States is stolen every year. 
   Vehicles are stolen for a variety of reasons, for example, for their parts, to be exported to a foreign country, or to be used in the commission of other crimes. In the United States stolen vehicles are recovered approximately 65% of the time. Over the past decade this rate has steadily declined, as car theft has become a major focus of organized crime. If car theft were a legitimate business it would rank in the top 60 of the nations largest businesses. 
   Vehicle theft is not just a property crime. To many people, the theft of a vehicle has a major impact on their lives. It affects them beyond the loss of vehicle. Often, they feel victimized and vulnerable, while at the same time they must cope with the inconvenience, time-consuming, and costly process of recovering or replacing their stolen vehicle. 
   With the advent of vehicle tracking systems, such as LOJACK® and ONSTAR®, car thieves have changed their practices in handling vehicles they have recently stolen. In areas where LOJACK® is available, thieves will often steel a vehicle and take it to a location away from their base of operations, park the car and wait. After the vehicle has sat for a couple of days, the thieves return to the car and take it wherever they had intended to when the vehicle was originally stolen. A primary reason car thieves use a “park and wait” approach is to ensure that the vehicle just stolen does not have a tracking system, which could alert law enforcement to the criminals&#39; base of operations. If the vehicle is still in the location where the thieves left it, the thief assumes the vehicle most likely does not have a tracking device, and is therefore a clean car. 
   Law enforcement officers, and police departments can only dedicate so much of their time and resources to tracking down stolen vehicles. In large cities with high crime rates, such as New Orleans, La., law enforcement officers have to deal with a vast number of crimes, many of which are more violent in nature than car theft, such as murder and rape. A law enforcement officer, while on a routine patrol in an area may pass a number of stolen vehicles parked on the street, or driving down the street. Unless the officer has a photographic memory he may not even realize that the vehicle he has just encountered is in fact stolen. 
   Therefore a system is needed to alert the officer that a stolen vehicle is in the vicinity of the officer. Furthermore, as vehicle tracking is not available in all areas, an is an expensive option a system is needed that will improve the likelihood of recovering a stolen vehicle even if the vehicle is not fitted with a tracking system. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to a law enforcement vehicle having at lease one camera mounted to a portion of the vehicle. The camera is configured to identify a license plate on a vehicle that is currently within the field of view of the camera. The camera can in various embodiments capture the image of the license plate while the vehicle is in motion, or can be used in a stationary environment. The camera provides an output signal indicative of the identified license plate as a digital image. This image is then provided to a processor stored on the vehicle. The camera can be mounted on several different locations on the vehicle. In one embodiment the cameras are mounted on font bumper of the vehicle. In another embodiment the cameras are integrated into the “A” pillar of the vehicle. In yet another embodiment the cameras are installed on the dashboard of the vehicle. 
   The Processor receives the signal or image from camera, and interprets from the image the characters that comprise the license plate. In other embodiments the processor can interpret for the received image other features of the vehicle. These features can include the make, model, type and colour of the vehicle. The processor then takes the recognized characters on the license plate and compares them with a list of stolen vehicle license plates contained in a database. The processor accesses through a storage device, such as a hard drive, the database of stolen vehicle license plates. The processor further provides an output signal to an output device when the processor identifies a match between the identified characters of the license plate and a plate in the database. 
   The output device provides an output that is detectable by the law enforcement officer, indicating to the law enforcement that a there is a match with an entry in the database. This output can be a visual output or an audible output. In one embodiment of the present invention the output of the system is displayed on a display device that provides the officer with more detailed information related to the identified license plate. In another embodiment the officer is presented with a lighted display that indicates to the officer that a match has been detected. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a diagrammatic illustration of a law enforcement vehicle in which the present invention is useful. 
       FIG. 2  is a block diagram illustrating the components of the present invention. 
       FIG. 3  is a flow diagram illustrating the steps executed by the present invention to identify a license plate. 
       FIG. 4  is a diagrammatic representation of the results of a license plate scan displayed on a display device. 
       FIG. 5  is diagrammatic illustration representation of a three light display device that is useful in the present invention. 
       FIGS. 6A and 6B  are an illustrative example of a law enforcement vehicle having multiple cameras in accordance with one teaching of the present invention. 
       FIG. 7  is a schematic diagram of a transmission system for continuous updating of an onboard stolen vehicle database on a law enforcement vehicle. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1  is a diagrammatic illustration schematically illustrating a law enforcement vehicle  100  environment in which the present invention is particularly useful. Law enforcement vehicle  100  is a motorized vehicle typically used in everyday law enforcement activities. Law enforcement vehicle  100  includes an engine  120 , a drive train  130 , a battery  140 , an occupant compartment  170 , a storage or trunk area  180 , and a communication system  190 . 
   Engine  120  provides mechanical power to drive train  130  to propel law enforcement vehicle  100  on a highway or other road surface. Engine  120  is in one embodiment an internal combustion engine using gasoline. However engine  120  can use diesel fuel, or engine  120  can be an electrical motor powered by batteries carried in law enforcement vehicle  100 , or can be any other device or system that can provide energy to propel law enforcement vehicle  100 . Engine  120  provides power to the wheels through drive train  130  by a mechanical transfer of energy. This transfer of energy can be done through the use of gears in a transmission  124 . However, other means of transferring energy from engine  120  to drive train  130  can be used such as chains, or direct drive. 
   Occupant compartment  170  (shown in cut out) provides an area or space for a law enforcement officer to sit and operate vehicle  100 . Compartment  170  has a driver&#39;s seat  171 , a steering column and wheel  172 , and a transmission control device  173 . A law enforcement officer sits in seat  171  while operating vehicle  100  and is restrained by a seat belt (not illustrated). Occupant compartment  170  has a plurality of windows that allow the officer to view the surrounding area without exposure to the natural elements. Windows are commonly made of transparent safety glass, but can be comprised of any transparent material that provides protection from the elements, such as Plexiglas®. 
   Storage area  180  (also shown in cut out) is located near the rear portion  104  of law enforcement vehicle  100 . In one embodiment storage area  180  is closed to the occupant compartment  170 , as in a typical sedan, such as a Ford Crown Victoria. However, storage area  180  can be open to the occupant compartment  170 , as in a typical sport utility vehicle or a station wagon, such as a Ford Explorer or Volvo V70. Storage area  180  provides an area to store tools and equipment commonly used in everyday law enforcement, such as flares, weapons, chalk, and form papers. When storage compartment  180  is open to occupant compartment  170 , a cover can be provided to shield the contents of the storage compartment  180  from outside view. In other embodiments, storage compartment  180  can be located in other areas of the vehicle  100 . 
   Vehicle  100  is also fitted with a communication system  190 . Communication system  190  allows the law enforcement officer to communicate with other officers as well as a central dispatch center. In one embodiment communications system  190  include a radio transmitter and an antenna  192  for transmitting voice information using radio technology. However, other forms of transmitting information can be used such as cellular technology, using for example General Packet Radio Service (GPRS), to transmit both voice and data. Further other forms of information can be transmitted via communicators system  190 . 
     FIG. 2  is a block diagram illustrating a law enforcement vehicle  100  including an imaging system  200  according to one embodiment of the present invention. Law enforcement vehicle  100  is similar to the vehicle illustrated in  FIG. 1 . This imaging system  200  includes a camera  210 , a processor  220 , a storage device  230 , and an output  240 . The law enforcement vehicle  100  is configured to capture an image  250  of a license plate  260  and compare image  250  of license plate  260  with a database  236  of license plates. 
   Camera  210  is connected to processor  220  and is configured to take an image  250  of an area with in a field of view  212  and to provide an image  250  to the processor  220 . In one embodiment camera  210  is located on a front portion  102  ( FIG. 1 ) of the law enforcement vehicle  100 . However, other locations on vehicle  100  can be used. Camera  210  is positioned on the front portion  102  of the law enforcement vehicle  100  such that the camera  210  is able to capture the image  256  of a license plate  260  of a vehicle when the license plate  260  is within the field of view  212  of the camera. Further, placing or locating camera  210  at the front of law enforcement vehicle  100  reduces the likelihood that camera  210  has an obstructed view caused by various parts of the vehicle  100  such as lights or wipers. 
   In one embodiment camera  210  is a digital camera that takes image  250  in a digital format. However, camera  210  can be any other device capable of providing an image in a format understandable by processor  220 . Camera  210  captures a picture or image  250  of a vehicle in front of law enforcement vehicle  100 , and converts image  250  to a digital format. The digital version of image  250  is provided to the processor  220  through camera output  214 . However, in alternative embodiments the conversion of image  250  to a digital format can be done by processor  220 . Camera  210  can be configured to capture an image  250  when law enforcement vehicle  100  is in motion, it can be configured to capture image  250  when stationary, or both. 
   Processor  220  is connected to camera  210 , storage device  230 , and output device  240 . Processor  220  is configured to analyze the image  250  to determine if the image  250  represents a stolen vehicle. In an alternative embodiment, processor  220  can also determine if the image  250  does not match characteristics of the vehicle scanned (i.e., the plate is on the wrong vehicle). In one embodiment processor  220  is a microprocessor. However, processor  220  can be a computer, a plurality of microprocessors, a portable desktop assistant (PDA), or any other device that is capable of processing an image  250  received from the camera  210  and comparing that image with information stored in a database. Depending on the physical size of processor  220  and the needs of the jurisdiction, processor  220  can be located in the occupant compartment  170  or in the storage compartment  180  of the law enforcement vehicle  100 . However other locations in law enforcement vehicle  100  are possible. 
   Processor  220  includes an input  222  where the image  250  is received from camera  210 . Processor  220  also includes an input/output  224  where processor  220  accesses or stores information on a storage device  230 . Finally, processor  220  includes an output  226  that provides an output signal  228  to the output device  240 . In one embodiment the output signal  228  is provided when the processor  220  has found a match between image  250  received from the camera  210  and a stored image. However, an output signal  228  can be provided for all images received, or only for those received images that matched a stored image and exceed a predetermined threshold value. 
   Processor  220  also includes at least two routines or programs for analyzing received image  250 . These routines include an analysis routine  221  and a comparing routine  270 . Analysis routine  221  is a computer program containing instructions which are executed by the processor  220  when an image  250  is received. Analysis routine  221  is programmed to identify letters and numbers that are contained within the image  250 . Analysis routine  221  also includes instructions to note or determine the location of each identified letter and number on the image  250 . Based on the location of each letter and number determined by analysis routine  221 , analysis routine  221  determines the complete license plate number  260  contained in the scanned image  250 . Analysis routine  221  also includes instructions to determine the state, province, or country of the license plate  260 . Analysis routine  221  can identify the letters and numbers in the image  250  through the use of character recognition that is based upon variations in color tones of image  250 , optical character recognition (OCR) protocols, or any other method for identifying letters and character strings in an image. In other embodiments analysis routing can identify a bar code or other identifications in the image  290 . Analysis routine  221  then converts this identified number to a format that is useable by comparing routine  270  when comparing the license plate number  260  with the information stored in database  236 . The operation of the comparing routine  270  will be described in further detail below. 
   Storage device  230  is connected to the processor  220  through the input/output  231  and provides the processor  220  with data related to stolen vehicles and their associated license plates when processor  220  processes image  250 . Storage device  230  can be a short-term memory device such as RAM or a long-term permanent memory system such as ROM, a hard disc, flash memory (DRAM, DVD) or other known storage elements. Storage device  230  is in one embodiment a computer hard disc drive having 100 gigabytes (GB) of storage space. However, other storage sizes can be used. Storage device  230  is configured to hold a database  236  containing information related to stolen vehicles and their associated license plates. Further, database  236  can include a database of all registered vehicle in the jurisdiction where the law enforcement vehicle  100  is located. However, other databases of registered vehicles can be used, such as for an entire state, province, or country and can also include a database of stolen license plates. In another embodiment storage device  230  is further configured to store the image  250  when processor  220  identifies a match in a match database  238 . 
   Storage device  230  and database  236  are configured to be updated using a data input device  280 . Data input device can be a CD ROM drive, a floppy disc drive, a USB port, a serial port or any other input device or protocol. In one embodiment database  236  is updated daily using a CD containing new information for database  236  that is placed in data input device  280 . However, other formats can be used for updating database  236  such as plugging system  200  into a host computer (not shown), or continuously by using communications system  190 , as will be discussed in  FIG. 7 . 
   Database  236  is computer-generated database of information related to stolen vehicles. Database  236  can be a database of stolen vehicles maintained by the local jurisdiction. However, other databases may be used, such as a national database of stolen vehicles, or an insurance database. Database  236  includes information related to each stolen vehicle contained in database  236 . This information can include, make, model, year, color, owners name, and owners address. However, more or less information can be provided in database  236 . Further, database  236  can include a list of license plates that have been stolen without the vehicle being stolen. The information included in database  236  for stolen plates include the same information provided for the stolen vehicles. 
   The output device  240  is connected to the processor  220  at  226  and is configured to provide an output  242  in response to a signal  228  from processor  220 . In one embodiment, output device  240  is a visual output indicating to the law enforcement officer that the processor  220  has identified a match. This visual output signal can be a single light, a red/green light, or any other visual indicator. In another embodiment output device  240  is a computer screen (illustrated in  FIG. 4 ) which provides the officer with the information contained in database  236  regarding the stolen vehicle when a match has been made with database  236 . In yet another embodiment, output device  240  is configured to provide an audible output in response to signal  228  received from processor  220 . This audible output can be a bell, a buzzer or a synthesized voice. However, other audible outputs can also be used. Further, output  240  can provide both audible and visual outputs in response to a signal  228  from the processor  220 . Output device  240  can also be configured to communicate with a central station ( FIG. 7 ) allowing communication to the central station that the law enforcement vehicle has encountered and identified a match with a license plate  260  in database  236 . 
   In operation, according to one illustrative embodiment, the law enforcement vehicle  100  is driven down a public street. Camera  210  constantly, (or at a predetermined rate) takes images  250  of vehicles it encounters on the road or highway according to a predetermined protocol. When camera  210  takes an image  250  of a vehicle license plate  260 , image  250  is converted into a digital format. The digital image  250  is sent to processor  220  for analysis with information continued in database  236 . Processor  220  processes image  250  using the analysis routine  221  to identify a portion of the image  250  that is representative of license plate number  260 . Processor  220  then passes the license plate number  260  to the comparing routine  270 , and stores the license plate number  260  in a temporary storage device  224  that is part of the processor  220 . However, this temporary storage can be located elsewhere Following the execution of the analysis routine  221 , processor  220  accesses the stolen vehicle database  236  from the storage device  230 . Using the comparing routine  270 , comparing routine  270  compares the license plate number  260  with the listing of license plate numbers in stolen vehicle database  236 . If comparing routine  270  finds a match between the license plate number  260  and a license plate number in database  236  that is listed as stolen, processor  220  provides output signal  228  to output device  240 , indicating to the law enforcement officer that a match with the database has occurred. Further, processor  220  stores in a match database  238  a copy of the image  250  for later use and recall. If there is no match between license plate  260  and a license plate in database  236 , then no output signal is sent to output device  240 . In other embodiments, processor  220  provides an output signal  228  to output device  240  indicating that a match was not found. 
     FIG. 3 . is a simplified flow diagram  300  illustrating the steps for identifying a license plate  260  in accordance with one embodiment of the present invention. At  310 , camera  210  takes an image  250  of license plate  260 . At  320 , camera  210  provides the image  250  to processor  220 . At  325 , database  236  is accessed by processor  220 . At  330 , the processor  220  compares the image  250  with a list of license plates stored in the database  236  using the comparing routine  270 . At  335 , processor  320  determines if a match is found in database  236 . At  340 , an output signal  228  is provided to output device  240  if a match has been identified. At  350 , a copy of the image  250  is stored in the match database  238  if a match has been identified. At  360 , an output signal  228  is provided to the output device  240  indicating that no match was made. 
     FIG. 4  is a diagrammatic illustration of an output device  240  according to one illustrative embodiment of the present invention. In the embodiment illustrated in  FIG. 4 , output device  240  provides a visual display through a display device  400  to the law enforcement officer. It should be noted that reference numbers used in  FIG. 4  that are the same as used in  FIG. 2  represent the same or similar items. 
   Display device  400  can display several items of information to the officer. While the displayed information illustrated in  FIG. 4  is shown in a particular layout it will be recognized by those skilled in the art that the arrangement and contents of the information displayed on display device  400  can be changed or rearranged depending on the needs of the jurisdiction and the information available in database  236 . 
   Display device  400  displays the digital image  250  of the license plate  260  captured by the camera  210 , in an upper right hand corner  410  of display device  400 . In an upper left hand corner  420  of display device  400  is displayed information related to the scanned license plate. This information can include such items as, the owner&#39;s name  421 , address  422 , vehicle type  423 , vehicle color  424 , as well as other registration information  425 . 
   On a bottom left portion  430  of display device  400  is displayed information concerning whether the vehicle identified by the system  200  is stolen at location  432 , or if there are any other discrepancies associated with the scanned license plate. This information can include such information as to when the vehicle was reported stolen is displayed at location  442 , or any crimes the vehicle may have been sighted at is displayed at location  444 . If the vehicle is not stolen or there are no discrepancies with the license plate, the display device can display “clear” or other phase indicating to the officer that the vehicle is not of further interest on line  432 . 
   On a bottom right hand side  440  of display device  400  is displayed information related to the scanned plate. This information can include the database  236  that provided the information  441  that the vehicle was stolen. Further, area  440  can provide information about the vehicle currently bearing the identified license plate. This information can include such items as the colour of the vehicle  442 , a generic type of vehicle  443  such as car, truck, trailer, etc. Data can also include the date of the scan  444 , scan status and quality  445 , an image number  446 , and a stored location  447  in motion database  238 . In other embodiments display device  400  can provide information related to the vehicle currently bearing license plate  260  such as make and manufacturer, using for example, a stored database of vehicle profiles, or by identifying the manufactures name through its name plate on the vehicle. 
     FIG. 5  is a diagrammatic illustration of an output device  500  having a three light indicator system for indicating to the officer the status of any scanned plate according to an alternative embodiment of the present invention. In this embodiment light  510  is a red light, light  520  is a yellow light, and light  530  is a green light. Red light  510  illuminates when system  200  detects that a plate  260  matching a plate in database  236  listed as stolen has been identified. Green light  530  illuminates when the system fails to make a match with a license plate in the database  236  listed as stolen. Yellow light  520  illuminates when the system encounters a technical difficulty. These technical difficulties can include such problems as identifying only part of a license plate, a communications error with the system, or any other fault that can occur in the system. Output device  500  can be combined with output device  400  from  FIG. 4  to provide a move efficient and safer system. 
     FIGS. 6A and 6B  are an illustrative example of a system  600  according to the present invention, as installed on a law enforcement vehicle  601 . A plurality of cameras  610 ,  612 ,  614  are included to provide an increased field of view for detection system  600 . Camera  610  is mounted on a right hand portion  611  of front bumper  605  of the law enforcement vehicle. Camera  612  is mounted on a center portion  613  of front bumper  605 . In other embodiments the camera can be installed on the areas of the law enforcement vehicle such as the window frame area of the pillar. Camera  614  is mounted on a left hand portion  615  of front bumper  605 . Cables  616  lead from cameras  610 ,  612 ,  614  to microcomputer  620  located in the trunk  680  of law enforcement vehicle  600 . However, depending on the size of microcomputer  620 , micro computer  620  can may be located in other areas of vehicle  601 . 
   Microcomputer  620  has three processors  622 ,  624 , and  626 . Each processor  622 ,  624 , and  626  is dedicated to one of cameras  610 ,  612 , and  614  respectively. Storage device  630  is integrated into the microcomputer  620 . Microcomputer  620  is connected to output device  640  located next to the driver&#39;s seat  671  of the law enforcement vehicle  601 . Output device  640  is adjustable so that the law enforcement officer can adjust the position of output device  640  to the most convenient and safest position. Communications device  690  is connected to the microcomputer  620 , and provides a communications link between the microcomputer  620  and a remote transmission station through antenna  692 . Also, power is provided to microcomputer  620  by battery  140 . 
     FIG. 7  is a simplified illustration of the present invention using a transmission link  700  between law enforcement vehicles  710 ,  711 ,  712  and a central computer  720 . Transmission link  700  allows a database  736  carried onboard each of the law enforcement vehicles  710 ,  711 ,  712  to update continuously, and also permits a central database  732  to receive updated data from law enforcement vehicles  710 ,  711  and  712 . Central database  732  can be updated by any method normally used by the local jurisdiction to update the database  732 , such as keying in new entries or downloading a new database. When the central database  732  is updated a signal  724  is sent over transmission link  700  to law enforcement vehicles  710 ,  711 ,  712 . When signal  724  is received by law enforcement vehicle  710 , database  736  carried onboard is updated to reflect any new information contained in signal  724 . Signal  724  can use any know format for transmitting information by a radio signal such as GPRS. Further, the vehicles  710 ,  711 ,  712  can update the central database  732  when the officer discovers a stolen vehicle. 
   In summary, the present invention is directed to a law enforcement vehicle  100  having a camera  210  mounted to a portion of the vehicle  100 . Camera  210  is configured to identify a license plate  260  on a vehicle that is viewed, and provides an output signal  214  indicative of the identified license plate  160  to a processor  220  carried on the vehicle  100 . Processor  220  is configured to receive the signal  214  from camera  210 , and compares the received signal  214  with a list of stolen vehicle license plates contained in a database  232 . The processor  220  also accesses a storage device  230  containing database  232  of stolen vehicle license plates. The processor  220  is further configured to provide an output signal  228  to an output device  240 . Output device  240  is configured to provide an output that is detectable by the law enforcement officer, indicating to the law enforcement that a there is a match. In another embodiment the system is configured to detect a license plate while the law enforcement vehicle is in motion. 
   Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.