License plate recognition at the entrance to the guarded object
Problem
Despite the attempts of the municipal authorities of megacities to build an efficient public transport system, many cities remain overloaded with cars. Almost every second resident of a developed country has personal transportation. Most car owners are able-bodied and get to work with their help. They park cars on the territory of an office building, factory or other facilities where thousands of people work every day. And to organize a checkpoint for such cars is quite difficult. Each vehicle is necessary to provide a pass or an electronic key, as well as to organize a four-hour duty at the guard post.
Monotonous labor often depletes the guards, which negatively affects their effectiveness. And fraudsters can seize a pass or an electronic key to illegally enter the protected area. It was with such arguments that the customer turned to us to create an autonomous access system based on the technology of automated license plates recognition.
Solution
To recognize a license plate algorithm needs to detect it in the vehicle. For this, we installed a camera on the parking entrance above the barrier in line of sight of which number plates visible. After detection algorithm crops frame by the plate's edges and align the image perspective.
After this processed frame runs through optical character recognition and the result compares with the local database. If the car is present in the database – the driver is allowed to enter and the barrier opens. Otherwise, the red light comes on and access is denied.
If the car, which was not allowed to enter, is delayed at the post for more than 20 seconds, an alarm will be sent to the guard.
In database saves all information about vehicles check-in on the barrier. The operator can easily and quickly find the records about the date and time of entry and exit of any car.
Results
The algorithm can recognize license plate numbers on a vehicle that moves at speeds up to 10 km/h with the accuracy of 96%. The efficiency of the guards increased, and cars began to pass through the post faster, which saves employees time to enter and park.
Besides, the procedure for issuing a permit for a vehicle to enter the territory of an enterprise has been simplified. For this, the security service only needs to enter the desired number into the database, as well as the validity period of the pass.