How does the facial recognition on a dell laptop works ?

does the facial recognition takes a picture of your face and then log you on your laptop?How does the facial recognition on a dell laptop works ?
I don't really know how Dell laptop works but I know the principle of Facial Recognition.





Facial Recognition is an application of Image Processing, specifically Pattern Recognition. First, when you register yourself camera on the laptop will capture your image and processes it to determine your facial pattern. For example, size of eyes and distance between them, the size of the nose and its shape, the shape and size of your mouth, skin texture and etc. Actually, laptop doesn't know what is eye or nose or mouth but it also determines those from patterns. When this is done the system will use this pattern as a reference to verify you in the future.





When you log in, the system will capture your image and determine the pattern and compare it to the reference. If the pattern is match, you will successfully log in.