How does the app work?

To get the licence plate from the image there are a number of operations to be performed.

• Cropping the image from the boundary box
• Noise filtering
• Binarisation of the image (getting the black and white image)
• Edge detection
• Character separation
• Optical character recognition

The result of these processes will be the licence plate number from the image. The final part of verifying the legality of the vehicle parked is to check to see if it exists in the local database.

The database is downloaded to the device when connected to the internet. From the database list, the user selects which database to download and it is then saved to the device, overwritting any previous versions.