There are many providers of license plate recognition products on the market. All of these solutions use various ANPR engines for plate capture and recognition. Do all these ANPR engines work the same way? And if not, what are the differences? What considerations should be taken into account in order to pick the best fitting ANPR technology for your projects? This article will take a closer look at the differences between ANPR engines and the possibilities they offer.
Roughly speaking, ANPR technology is available in two flavours. One is offered as a one-size-reads-all engine, often called a generic engine. The other is a country specific trained engine, where a number of country modules can be selected. Most system integrators use third party ANPR software in their products, as there are only a few companies, that offer an in-house developed ANPR engine
AVUTEC is one of the companies, that developed it’s own engine and country modules from scratch. The engine is trained on hundred of thousands of images, using both computer vision and deep learning techniques. On top of country specific recognition, AVUTEC’s ANPR engine can be tailored to meet unique license plate recognition requirements.
Let’s take a closer look at the different kinds of engines having their own pro’s and cons.
1. Generic ANPR
A generic ANPR engine is looking for characters in the image and reads them as they are. They do not take country syntax, plate type or fonts into account. These are based on classic OCR (optical character recognition) technology. Recognition results are not restricted to characters belonging to license plates and will not tell anything about the country of origin or what so ever.
Imagine the improvement in accuracy, when implementing a plate finder before the actual recognition starts. In AVUTEC terminology the improved version of a generic ANPR engine is called the XX-module.
2. Country specific modules
A country specific module is trained on country-specific syntaxis, alphabets, fonts and plate types. This makes it outperform the generic ANPR engine in accuracy by multiple percentages. Different country modules can be stacked, in order of priority and statistical occurrence. Enhancing accuracy by adding multiple country modules, often comes with a price: a stretched latency and lower reading speeds. Luckily all AVUTEC products are equipped with a fair amount of processing power and hardware optimised ANPR software. Stacking the modules will not endanger the required capture speeds.
3. Tailormade ANPR modules
Tailormade ANPR is trained to meet project requirements. A recent project was about the automation of entry allowance for a contracting company. The company equipped all their machinery with custom company license plates. After implementing the syntax, the font and plate types, the plates got recognized straight away and the machinery started to go in and out freely. The tailormade module is added to the regular ANPR engine to open the barrier, for both regular vehicles and company machinery. All can be achieved in one device on the edge, the Gatekeeper!
ANPR-X: the future of ANPR
With technology evolving, the next step in license plate recognition can be taken. To stay ahead of trends and offer the best possible product, AVUTEC developed ANPR-X. With ANPR-X innovative technologies open the way for a wide range of possibilities. Above license plate recognition, ANPR-X adds contextual intelligence, scripting and additional video content analysis. It takes ANPR to the next level and offers a versatile future proof product to customers. The best thing is, it can still be deployed completely running on the edge.
The advantages of versatile ANPR engine
LICENSE PLATE
COUNTRY SPECIFIC
XX-MODULE
The versatility of the AVUTEC ANPR engine allows for a project specific ANPR configuration. In a standard product with third party ANPR software this is not feasible.
In a typical AVUTEC installation, recognition modules are combined and stacked in the order of project priority. They start with the country-of-installation module and end with the XX-module. When a license plate is captured, it will be processed in that order. When the first module cannot recognize the plate, it’s journey will continue to the following one. The XX-module at the end of the pipeline will read the license plate, that does not fit in any previous syntax, font or plate type.
Conclusions
The requirements of the project will define the selection of a generic, country-specific or tailormade engine. The more specific the engine, the more accurate the recognition will be. The strictness of the engine on the other hand, cannot identify a license plate, that does not match the specifications. If all license plates need to be read and accuracy is not top priority, the choice for the generic engine can be the best.
AVUTEC offers an ANPR engine that suits any ANPR application. For questions or consultancy on the AVUTEC ANPR engine and it’s modules, please contact our sales department at [email protected] or +31 88 2444 010.
