WO2001035372A1

WO2001035372A1 - System for surveillance of vehicular traffic on roads and highways

Info

Publication number: WO2001035372A1
Application number: PCT/IT2000/000441
Authority: WO
Inventors: Romolo Donnini; Andrea Righi
Original assignee: C.R.A.F.T. S.R.L.
Priority date: 1999-11-09
Filing date: 2000-11-03
Publication date: 2001-05-17
Also published as: ITFI990230A0; IT1310318B1; ITFI990230A1; AU1883501A

Abstract

The system comprises, at each of two local capture stations, spaced apart (1, 3), an infrared illuminator (11) capable of illuminating from the rear the vehicles traveling in one direction; a video camera (13) capable of capturing the rear image of the vehicles in transit; an electronic interface (15) capable of processing the images captured by the video camera, carrying out the optical recognition of the characters on the license plate and storing images and data, at least temporarily; a timing device; and a system (17) of receiving and transmitting the data. A remote station (5) comprises: a receiving and transmitting system (53) for dialogue with said local stations; a computer (51) capable of processing the data received from the two local stations (1, 3) and calculating the mean speeds from these data; and a selection system for the extended storage of the images of vehicles in respect of which an infringement has been detected.

Description

SYSTEM FOR SURVEILLANCE OF VEHICULAR TRAFFIC ON ROADS AND HIGHWAYS

DESCRIPTION Object The invention relates to a system for surveillance and monitoring of a section of urban or rural highway or other road, with a length variable from a few meters to several kilometers, for 24 hours a day, with the capacity of calculating the mean speed of the vehicles passing along said monitored section, and for further purposes of identification, monitoring and the like. The system is particularly designed to provide a means of deterrence tending to discourage the drivers of vehicles in transit along the monitored sections from traveling at speeds above the permitted limit. This is because the system is capable of identifying the vehicle, by recognition of the license plate of the vehicle in transit, and of supplying documentary evidence - consisting of a video frame - by means of which the relevant authorities are enabled to prosecute the offender for exceeding the permitted speed limit.

For this object and for other possible objects specified below, the system for surveillance and monitoring of vehicular traffic essentially comprises, in combination: - at each of at least two local capture stations, spaced apart: an infrared or equivalent type of illuminator capable of illuminating from the rear the vehicles traveling in one direction; a video camera capable of capturing the rear image of the vehicles in transit; an electronic interface capable of processing the images captured by the video camera, carrying out the optical recognition of the characters on the license plate and storing images and data, at least temporarily; a synchronizing timing device; and a system of receiving and transmitting the images and data (GSM modem or the like);

- at a remote station: a receiving and transmitting system (GSM modem or the like) for dialogue with said local stations; a computer capable of processing the data received from the two local stations and thus calculating the mean speeds; and - a selection system for the extended storage of the images of vehicles for which an infringement has been detected, while the license plates of the vehicles are stored permanently in all cases.

The computer is capable of calculating the mean speed of a vehicle in transit between the two local stations, according to the measured transit times of each vehicle between the two local stations. It is therefore necessary to synchronize the timing devices of the two local stations.

When the mean speed of a vehicle in transit has been calculated, and if an infringement due to excessive speed has been detected, the images of said vehicle will be stored, while all the other captured data will be deleted unless their storage is required for other reasons.

This is because, since the fundamental operating principle of the system is based on the identification of a vehicle by means of video capture, the system can be used to monitor a district, with the capacity of indicating the passage of a vehicle which is stolen or which has to be indicated for any reason. Furthermore, the system can also be used for a simple count of the vehicles in transit, for a traffic census. Moreover, the system in question can also be used to regulate access at automatic barriers for vehicles authorized to pass, or as a replacement of the existing highway system known as Telepass, with the advantage of not requiring a transceiver on board of vehicles; this results in a lower cost and makes it unnecessary for the user to carry out any installation work.

The system can also be used to check the wearing of helmets by moped riders: this requires the presence of an operator at the central station, in other words at the remote station, for checking the images of two-wheeled vehicles photographed from the rear, in order to store the images relating to infringements.

The drawing shows the guiding principle of the invention.

Fig. 1 shows the components of one of the local capture stations and of the remote station;

Fig. 2 shows the installation on a highway with two lanes. Two local capture stations 1 , 3, spaced apart by a considerable distance which may be of the order of several hundred or even several thousand meters, are provided on a lane C1 and/or C2; the station 1 is located upstream and the station 3 is located downstream with respect to the direction travel F. Each local capture station, such as that indicated by 1 in Fig. 2, comprises an infrared or equivalent type of illuminator 11 , capable of illuminating the rear part of the vehicles V in transit, the IR illumination not being visible to drivers even at nighttime. The number 13 indicates a video camera, which is capable of systematically capturing the rear images of the vehicles in transit on the available lane or lanes. The number 15 indicates an electronic interface capable of processing in real time the images captured by the video camera, for the optical recognition of the distinctive symbols on the license plate and for supplying these data to a receiving and transmitting system 17, such as a + modem or the like, capable of radio transmission of the data.

The number 5 indicates a remote station, which is designed to interact with at least one pair of local capture stations 1 , 3, located on the section of road to be monitored. This remote station 5 comprises a computer 51 and a receiving and transmission system 53 capable of dialogue with the systems 17 of the local stations 1 and 3 or with other systems as well. The data on the exact time of transit of each vehicle are received at the remote station; since the timing devices of the system are synchronized and the distance between the two local stations along the monitored section of road is known, the mean speed of each vehicle in said section can be calculated. The remote station can thus process sufficient data to identify any infringements ancl thus the necessary and appropriate images and data for providing documentary evidence of infringements can be stored, while captured images and data relating to vehicles complying with the regulations can be deleted, if they are not to be stored for other purposes. In practice, the remote station is made to store the data captured by the video cameras, at least temporarily, and to extend the storage of the data on vehicles for which this is found to be necessary, because of the exceeding of a speed threshold, or coincidence with data relating to a request for identification (in case of theft or the like) or for other reasons; the capacity for storage and selective extension of storage is delegated to the remote station.

It is clear from the above that it is possible to carry out monitoring, not in the conventional temporary way at a single location - as is done at the present time - but by extending the surveillance to a whole section between two local stations, in such a way that the driver of a vehicle, in order to comply with the regulations, must keep his mean speed within the permitted limits throughout the transit between the local stations; this is because a mean speed in excess of the permitted limit constitutes proof that peaks of speed above the permitted limit have been reached within the monitored section (between the two local stations). The length of the section can also be varied considerably, while maintaining the same quality of performance, by specifying a distance which can vary within the limits of a few meters and several kilometers, or even beyond these limits.

A plurality of stations in series can cover any section. This can also be useful for indicating, for example, the movements of a stolen vehicle, whose points of entry to and exit from a highway, for example, can be determined. If monitoring personnel are available, the images of two-wheeled vehicles whose drivers or passengers are not wearing helmets can be stored.

A fundamental advantage of the system in question is that it can operate continuously for 24 hours a day, since the monitoring is carried out by means of video cameras capable of acquiring the image even at night, because the field of vision of the video camera is illuminated by means of infrared illuminators. Additionally, the system in question can operate in fully automatic way and therefore the continuity of operation can be provided without the need to employ personnel on night shifts, unless this is expressly required by the law. Moreover, in respect of the continuity of power supply, there are no limits on continuous operation for 24 a day, since the system is powered from the mains supply, and the devices can be mounted on existing electrically powered structures such as traffic lights, lamp posts, illuminated signs, or the like, which are generally present along roads and highways. The electronic interface 15, connected to the video camera 13 which observes the passage of the vehicles, is capable of identifying the vehicle by reconstructing the license plate, using, for example, the Optical Character Recognition (OCR) technology which enables text characters .to be recognized in a digital image acquired in any way. When the license plate has been decoded and the vehicle has thus been identified, this information is transmitted to the remote station 5 together with the exact time of passage of the vehicle through the monitored transit point. When this has been done by the two local stations 1 and 3 at the two successive transit points, the distance between these being known, the remote station 5 receives the data and has calculation and storage resources such that it can process the data to calculate the mean speed maintained over the whole section. To ensure the reliability of the measurement of the mean speed, the remote station must be able to correct possible misalignments between the clocks of the local stations in the two successive transit points, in such a way that a possible lack of synchronization between the two local timing devices does not affect the calculation. The remote station must therefore be equipped to carry out the periodic adjustment of the clocks of the local stations, in order to reduce to a minimum the tolerance to be allowed in the final calculation of the mean speed. This tolerance is that which serves to compensate for system errors and is expressed as a percentage of the calculated mean speed. For example, if the system has a tolerance of 10%, then, for a limit of 60 km/hr, speeds in excess of 66 km/hr, for example, will be considered to be infringements. When the remote station detects a speed infringement, rt requests each of the two electronic interfaces 3, 5 located at the two monitored transit points to transmit the image on which the license plate of the vehicle concerned has been captured, in order to provide documentary evidence of the infringement. When stored and printed out at the remote station, this image constitutes a document on the basis of which the offender can be prosecuted: the images are downloaded from both transit points, since the prosecution is based on the mean speed reached over the whole section and compared with the permitted limit, and therefore both items of evidence (video frames) are required.

After the downloading of the images relating to the infringement for which prosecution is intended, all the images and data acquired locally, by the electronic systems monitoring the transit points at the local stations are deleted to save space. Finally, the locally acquired images are stored only for as long as they are required at the remote station 5 for the calculation of the mean speed and the selection, after which the temporarily saved images are deleted, even if they have not been downloaded, while the information on the license number and time of transit, which occupies less memory space, is stored permanently. These residual data can be deleted subsequently when they are no longer useful for other investigations such as the indication of stolen vehicles or the like.

It is also possible to provide convenient calculation of the traffic flow during specific periods of time and at specific times of day and/or on specific days of the week or the like, again by making use of the acquired data which are selected chronologically and counted, and which may be acquired from only one of the two local stations.

It is to be understood that the drawing shows only an example provided solely as a practical demonstration of the invention, this invention being variable in its forms and arrangements without departure from the scope of the guiding concept of the invention.

Claims

1. A system for surveillance and monitoring of vehicular traffic on highways and other roads, characterized in that it comprises, in combination:

- at each of at least two local capture stations, spaced apart: an infrared (IR) or equivalent type of illuminator capable of illuminating from the rear the vehicles traveling in one direction; a video camera capable of capturing the rear image of the vehicles in transit; an electronic interface capable of processing the images captured by the video camera, carrying out the optical recognition of the characters on the license plate and storing images and data, at least temporarily; a synchronizing timing device; and a system of receiving and transmitting the images and data (GSM modem or the like) to the remote station;

- at a remote station: a receiving and transmitting system (GSM modem or the like) for dialogue with said local stations; a computer capable of processing the data received from the two local stations and thus calculating the mean speeds; and

- a selection system for the extended storage of the images of vehicles for which an infringement has been detected, preferably at the remote station.

2. The system as claimed in claim 1 , characterized in that said computer is capable of calculating the mean speed of the vehicle in transit between the two local stations.

3. The system as claimed in claims 1 and 2, characterized in that it comprises means for synchronizing the timing devices of the local stations.

4. The system as claimed in the preceding claims, characterized in that it comprises means of storing and recording the transit of ^authorized vehicles in a data communication transit system (Telepass, etc.).

5. A system for surveillance and monitoring of vehicular traffic on roads and highways, the whole as described and represented by way of example in the attached drawing.