In the previous part of ANPR terminology, you could read about photography terms used in ANPR. In the present part, you can review key concepts and their names in ANPR – with brief explanations.
Transportation Terms in License Plate Recognition
License plate recognition is closely related to transportation. This is why a lot of traffic-related terms appear in the description of ANPR products. The following are just a few examples.
Not Strictly ANPR-Specific Terms
- Vehicle registration plate types like vanity plates, also called personalized plates, and a mixture of reflective (sometimes called retroreflective), and non-reflective plates.
- Application areas, or fields of use, is an umbrella term. It encompasses, for example, speed enforcement, sometimes called road speed limit enforcement, and traffic enforcement, congestion charging, also called road congestion pricing, and road pricing (also known as tolling)
- Industry stakeholders include systems integrators companies that build turnkey systems out of component subsystems or traffic authorities maintaining the rule of the road by monitoring traffic via patrol cars and multi-sensor traffic points
Terms Specifically Related to ANPR
- Fixed ANPR is a device with a permanent position on the roadside or on an above-the-road structure called gantry to capture license plates.
- Portable and mobile ANPR systems are operated from a tripod or from a patrol vehicle, or can even be hand-held units.
- A trigger is a traffic detector to sense the presence of a vehicle. Its signal starts the process of automatic number-plate recognition. Triggering may be physical, like an inductive (or induction) loop installed into the road, or a motion detector sensing moving objects, similar to the ones attached to outdoor automatic lights. Triggering can be software-based as well and promising Vehicle Detection technologies are in the works.
- ANPR range expresses the distance from which you can capture a vehicle’s plate. This range varies widely from a few meters to hundreds of meters, depending on the device.
- A red-light camera senses traffic offenders driving through red traffic lights and takes photos. Traffic authorities can use those pictures as evidence.
- An image buffer is the capacity of the license plate recognition system to temporarily store images for processing.
- Related technologies, (like information technology), and their technical terms like bandwidth, processing power, data storage capacity, and encryption (where data is encoded and only visible to those who can decode it) are also common terms.
- Onboard vs external ANPR refers to the location where license plate image processing occurs. Plate recognition can happen on board the camera or, alternatively, outside the camera, on a central server or local computer. Both types of system architecture have advantages and drawbacks.
In the third part of the article, you can read about spelling and term differences between the US and UK English in ANPR.