If you're into deep learning and love cats, this project is for you. Created and shared by a Reddit user known as Eee_bume, it relies on image recognition and deep learning to scan cats using a Raspberry Pi 4.
The Raspberry Pi is connected to a camera which parses images through Tensorflow looking for a cat. If a cat is detected with possible prey in its mouth--things like mice, lizards, ridiculously large moths--the system sends an alert through Telegram.
This system could easily be adapted to a controlled cat door, only allowing access if the cat has been deemed free of unwanted critters. According to Eee_bume, the project results were fairly reliable using just a small sample size of 150 images.
The notification process is handled through Telegram. When the system first boots, a bot sends a notification message through Telegram. As cats are detected, the Telegram bot will send a message along with an image of the suspected cat.
If you'd like to take a closer look at this project or even make it for yourself at home, visit the official project page on GitHub.