ANPR camera

Automatic number plate recognition camera

Automatic number plate recognition with an ANPR camera, ANPR for short, is quite different from ordinary number plate capture. Number plate capture with a camera generally refers to a security camera that is sharp enough to read a number plate.

Automatic number plate recognition is a separate software module that stores number plates in a database and makes them easy to look up, for example by time or by part of the plate.

A barrier with number plate recognition and a camera can also be very useful. This can be linked, for example, to a barrier at a car park. A number plate can then be put on a whitelist or blacklist. This lets cars drive in without buying a ticket, or refuses them entry.

ANPR/LPR: number plate recognition with Milestone XProtect

Milestone XProtect® LPR is number plate recognition software that reads vehicles' number plate information and links it to video. As a fully integrated part of the XProtect® Smart Client, XProtect LPR has a wide range of applications, including access control, theft prevention, loyalty programmes, toll roads and border control.

Advanced matching logic lets you compare recognised number plates with predefined lists and trigger automated actions, such as opening a gate, which increases productivity.

What should you consider when implementing an LPR system?

LPR, short for licence plate recognition, is another name for ANPR (automatic number plate recognition). Recording number plates automatically does come with a few catches. It is therefore important to carefully consider the following questions when rolling it out. A barrier with number plate recognition must be configured properly.

Barrier with number plate recognition

A barrier with number plate recognition can be a good addition to your complete security system. Because the barrier opens automatically, nobody has to verify and open it manually.

The vehicle drives over a detection loop, so the barrier knows a vehicle is waiting in front of it. A camera then takes a photo of the vehicle and passes it to the software. When the software recognises the number plate, the barrier opens automatically.

Number plate recognition software

ANPR number plate recognition software works with a camera loop. This technology typically uses a high-speed camera with an IR filter, or an IR and HD camera; this can differ per system. The photo taken is processed by OCR (optical character recognition) software, which converts it into an alphanumeric result.

Some factors can affect such a system, such as a dirty number plate, poor lighting or the weather. Fortunately, there are software solutions to overcome this. We can give you expert advice on this.

Storing camera footage and metadata

As with ordinary camera footage, you do not keep the recordings for longer than necessary. The Dutch Data Protection Authority (Autoriteit Persoonsgegevens) uses a maximum of 4 weeks as a guideline, unless there has been an incident. However, there is also metadata. This means you store the metadata separately from the footage.

In short, you can still search for number plates. You can still consult the automatic number plate recognition module and see, in no time, a list of every moment the plate passed. A barrier with number plate recognition and a number plate camera record automatically.

Using the right type of ANPR camera

ANPR cameras are different from "ordinary" security cameras. They often have a Wiegand connection. Wiegand is a protocol widely used in access control applications.

In short, you can also easily link your access control to it. Paxton Net2 is an example. These ANPR security cameras are also much more resistant to glare from car headlights.

Halogen, laser and xenon headlights are no problem. Even if the car is driving on full beam, the ANPR camera will recognise the number plate without any trouble. This is thanks to the infrared LEDs on the ANPR camera.

These are designed specifically for this purpose. By setting the ANPR camera to a fixed shutter and gain, it is almost 100% certain that the ANPR camera captures the number plate.

Number plate country library

With many ANPR software solutions, you need to buy a data library per country or continent so the number plate can actually be linked to a country. When you buy ANPR, you get a general module (EU-X).

This makes sure all number plates can be recognised globally. If a car is Russian, for example, but you have not bought that country, the plate is stored as EU.

So you can still search on the numbers and letters in the plate; the software just does not know which country it comes from. Why would you buy this country library at all, you may wonder, if the software recognises the plate anyway? Take a Dutch number plate as an example.

Barrier with number plate recognition? If the software reads the plate but does not know the specific characteristics of the country, it may read a 1 as the letter I, or a zero as an O. The same goes for a B that may be an 8. In short, it is important to consider this carefully when rolling out.

Five country libraries are included as standard. Expanding is definitely an option, but not always necessary. That is why you should have an automatic number plate recognition solution rolled out by professionals.