Raspberry Pi Project Uses Artificial Intelligence to Detect License Plates

(Image credit: Robert Lucian Chiriac)

When you're a software and hardware engineer sometimes you need a little challenge. Engineer Robert Lucian Chiriac's latest Raspberry Pi creation can detect license plates and read the characters with fairly decent accuracy. This is an involved project that relies on machine learning to properly interpret images from the camera into discernible text.

The primary license plate reading function is constructed using three separate applications (there are more used throughout the project, but these three are critical). Chiriac used the YOLOv3 object detection algorithm to create a bounding box around each license plate it detects from the camera input. The image within the bounding box is sent to CRAFT, a text detecting application. Once the location for each character in the plate has been identified, the information is passed along to CRNN to predict the actual text.

Chiriac mounted the Raspberry Pi, GPS module, 4G module and Pi camera to his car's rear-view mirror with a 3D-printed unit he designed. The Pi camera is even adjustable with a ball-joint swivel mount.

(Image credit: Robert Lucian Chiriac)

Robert originally shared this project on Reddit earlier this month. Check out the full thread for yourself to see more details about the project and questions answered by Robert. He also shared a blog post with a complete breakdown of the project construction. You can see more of his work and follow him on his official website.

Ash Hill
Contributing Writer

Ash Hill is a contributing writer for Tom's Hardware with a wealth of experience in the hobby electronics, 3D printing and PCs. She manages the Pi projects of the month and much of our daily Raspberry Pi reporting while also finding the best coupons and deals on all tech.

  • bit_user
    For the average person, the best use case I can think of would be to get real-time alerts when someone pulls into your driveway. You could use the license plate reader to suppress the alerts for known cars, or to perform other custom actions.

    I don't see any good that would come of integrating a license plate reader into your car. At least, I don't see any benefit that you couldn't get by just having a regular camera recording, which is what you really want to have in case of an accident or incident.
    Reply
  • bit_user
    BTW, here's an open-source License Plate Recognition project that's been around for a little while. I'd imagine a Pi v4 is powerful enough to do it in realtime:

    https://github.com/openalpr/openalpr
    Note that it's only free for non-commercial use. Otherwise, you have to pay $.
    Reply