Double license plate recognition can achieve 100% reliability

Automatic Number Plate Recognition - ANPR is an access control method that has a great impact and importance in the parking and mobility sectors. A license plate reader increases not only the drivers' flow at access points, but the user experience in the entire parking facility. 

Regarding the reliability of license plate recognition camera results in different countries, it is common to give no data at all or to make claims ranging from 92 to 98% success rate. Although these are usually good results, accuracy is a very important factor when talking about usability in parking systems.

Quercus Technologies has conducted and continues to conduct several reliability studies to improve results and prevent errors. In the same way, it works in the line of maintaining good reliability results in license plate reading: in-house technology that integrates access control cameras and parking guidance sensors.

When we talk about percentage, we are usually inclined to believe that high rates will compensate for errors. This is partly true, as the camera that makes fewer errors is more reliable, but any failure in reading will leave the driver whose license plate is not recognized unsatisfied. It is therefore important to get as close as possible to the 100% rate to achieve the best possible user experience.

How to achieve the closest reliability to 100%? 

With double license plate reading. In many cases, license plate reading technology detects errors external to the license plate recognition software. In other words, problems and defects that have nothing to do with the LPR cameras and their license plate reading capabilities. For example, damaged license plates due to weather, plate breakage, fixing screws and frames. 

The condition of the license plate can also be affected by different elements obscuring part of the license plate, such as a trailer tow bar, dirt on the vehicle plate, or even part breakage of the plate due to snow melting products on highways and roads.

In order to get the reliability rate as close as possible to total success, two license plate reading cameras can be installed in the same access lane where they recognize the front and rear license plate at the same time.

SmartLPR Access offers the option of integrating two cameras per lane for double reading. This system is called HRR (High Recognition Reliability): a highly reliable system that combines both front and rear capture. In this way the system is able to combine the reading of both cameras and build a reliable system so that, for example, a parking subscriber can enter and exit without a ticket. 

This is often necessary due to the poor condition of mainly the front license plates. These are much more exposed than the rear ones, even though front reading is more common in most parking facilities. That is why Quercus Technologies bets on this feature; it implements the intelligent combination of the two license plates, increasing the recognition success close to 100% with two LPR cameras.