ERCIM News No.43 - October 2000 [contents]

Identifying Vehicles on the Move

by Beate Koch

Research carried out in Germany in the field of information and communications technology is extremely diverse in nature. A major role is played by the Fraunhofer-Gesellschaft with its total of 47 Institutes and branches in the USA and Asia. The following example shows how the preliminary research conducted by the Fraunhofer Institutes - with a constant focus on the longer term - enables scientific findings to be converted into pioneering and marketable products.

Automated image-processing systems constitute a booming market with double-digit growth rates. The breakthrough was achieved in the combination of camera and information technology - thereby implementing mechanized sight, far swifter and more reliable in operation than the human eye.

For many years, Fraunhofer researchers in Berlin have played a leading role in the development of intelligent systems for the identification of signs and symbols. Their latest breakthrough is a compact system capable of recognizing registra-tion plates and loading signs on vehicles in flowing traffic up to a speed of 120 km/h.

Bertram Nickolay of the Fraunhofer Institute and his team have constructed an entire family of modules that allows various components of road traffic to be recorded and automatically analyzed. The individual components can be put together in any combination. “Our ISY family solves many tasks in traffic engineering,” reports project leader Nickolay, proudly. ISYCOUNT allows vehicles to be counted in any traffic situation. The data are then used as the basis for telematic systems that control traffic flow and prevent holdups. ISYTRACK combined with ISYPLATE can be used to register vehicles entering and leaving waste disposal sites or gravel pits. Unlike private cars, commercial trucks carry their identification plates in different places, and they have to be located amidst a number of other signs, such as the company logo and signs indi-cating the laden weight and the nature of the goods being transported. ISYSHAPE registers the shape and dimension of a vehicle and is then able to identify its type from specific features of its design, and make a rough classification of its loading.

The latest addition to the family is a software program that enhances the image recorded by the automatic recognition system: ISYFLASH is capable of determining the ideal moment at which to capture an image, even if the vehicle is traveling at high speed. This ensures the highest possible resolution and the maximum degree of certainty in identifying the registration plate. The family of modules is based on the latest methods of intelligent character recognition (ICR) combined with learning processes on the basis of soft computing. They are capable of solving complex problems, even in the presence of out-of-focus or doubtful elements such as mud on the number plate, deformations or unusual colors. Most of the currently available re-cognition systems are only able to identify license plates common in one or a few selected countries. They have problems if the type and color of the background changes, or if a new character font is introduced. The system developed by the IPK is already capable of recognizing signs on vehicles registered in 25 different countries; it does not matter if the vehicle is registered in Germany, the UK, Poland, Israel, South Africa or even Russia. That is because the system learns fast: Given a few samples, such as actual number plates or video pictures of a new character font, the system trains itself and by the next day it is capable, for example, of reading signs written in Cyrillic script. The IPK is marketing its software through a number of international cooperating partners.

A further advantage of the system is that the camera and the electronic analysis circuits are incorporated in a small compact unit to make the equipment more portable and economical. The camera and the processor are merged into a single ‘smart device’. This simplifies the structure, reducing the number of interfaces and hence the number of potential sources of errors. This portable apparatus possesses several features that give it the edge over other recognition systems used to identify and record moving vehicles: Laser scanners are more expensive to maintain, light barriers are more susceptible to faults. Work-intensive earth-moving operations are required in order to lay induction loops in the road surface. And none of these systems are infallible - they can just as easily be triggered by a person or an animal passing through their field of recogni-tion. ISYFLASH uses image-analysis methods to exclude such disturbances. The portable units are ideal for monitoring and regulating the access ramps and exits of high-rise car parks and industrial sites, quickly and smoothly. Police forces in a number of countries have also indicated considerable interest in the system devel-oped by the IPK, which can be used to help track down criminals on the road. Installed in a police vehicle, the mobile ISYFLASH equipment can identify the registration numbers of other road users while on the move or from a parked position alongside a highway or at one of its exits. If a car bearing the suspect number drives past, an alarm lamp starts to flash. Other, innocent drivers are then spared the inconvenience of having to stop at police road blocks during a large-scale police operation.

Videomaut is not exactly a new idea, but it is still not ready for widespread implementation: Drivers slowly steer their car through the video-control barrier, in the hope that the camera will register the number plate correctly as they move past at walking speed. If not, the barrier remains closed and the driver has to back out and join the line waiting at the regular toll booth. The intelligent recognition system developed by the researchers in Berlin is different: Barriers and toll booths are obsolete, and the driver doesn’t even need to brake to a slower speed. A number of countries are considering automating their highway toll systems using the software from the IPK. The advantage: No more tailbacks at the toll stations, and useful telemetry data for traffic regulation.

Please contact:
Bertram Nickolay - Fraunhofer Gesellschaft
Tel: +49 30 3 90 06 2 01