How does OpenCV face recognition work?

It is a machine learning based approach where a cascade function is trained from a lot of positive and negative images . It is then used to detect objects in other images.

We have face embeddings for each face in our data saved in a file, the next step is to recognize a new image that is not in our data. Hence the first step is to compute the face embedding for the image using the same network we used earlier and then compare this embedding with the rest of the embeddings that we have .

When it comes to a good, all-purpose face detector, I suggest using OpenCV’s DNN face detector: