This is a simple project I have created for the learning purpose on how facial recognition can be done. It has been coded in Python and also we would be using the open source library - OpenCV. (https://opencv.org/)
OpenCV originally written in C/C++ has bindings with Python now. It uses cascasdes to break down the stages for recognising a face. For each block it does a quick test and then goes into the details based on results. These cascades are actually XML files that detect objects.
Here , we tried a few samples to detect faces of human by python and OpenCV in Google colab Notebook.