Automatic License Plate Recognition

What is ALPR?

ALPR or LPR (Automated License Plate Recognition) systems take an image of the vehicle’s license plate and convert it to binary digits using optical character recognition.  ALPR uses 360-degree cameras and object recognition technology. Vehicle plate numbers can be transformed from simple images to textual data throughout this process.

There are two types of ALPR: stationary, which uses infrared (IR) cameras at high fixed points, and mobile, which uses vehicle-mounted IR cameras. Stationary cameras can be mounted on signs, streetlights, highway overpasses, or buildings as a cost-effective way to monitor moving and parked vehicles.  Mobile ALPR software use multiple cameras mounted on a car. As the vehicle moves, it photographs license plates and transmits plate data to a database.

Advantages of ALPR technology:

  • Works in limited lighting conditions and can record the license plate of a moving car
  • Can perform data collection and reduces human error
  • Increases safety and efficiency. Property protection and crime deterrent.

ALPR systems are increasingly embraced by law enforcement agencies throughout the country and worldwide to improve their enforcement and investigative capabilities.  ALPR helps them to expand their collection of relevant data.  It also shortens the time it takes when searching for partial or whole license plate information for things like stolen vehicles and other vehicles of interest.

In many cities, parking officers still examine parked vehicles manually instead of utilizing ALPR technology.  This method of parking enforcement is no longer 100 percent efficient. Patrolling the city routes and inspecting for physical parking permits is complicated, costly, and time-consuming.  Today, parking enforcement automobile patrols are the leading users of portable ALPR cameras.

One famous use case for ALPR is tracking vehicles entering and exiting neighborhoods.  SafePassage Solutions has built a high-performance automatic detection and recognition system for license plates in real-time.  Learn more about ALPR for your community by visiting