Face Recognition

Face recognition is a technology that lets a computer figure out who someone is just by looking at their face in a photo or video.

Just as a person who has seen a friend's face once can recognize them again on the street, a computer converts features like the distance between the eyes, the position of the nose and mouth, and the shape of the face into numbers, stores them, and compares them with a new face it encounters. If the two sets of numbers are similar enough, it concludes they belong to the same person. Unlocking a smartphone with your face, passing through airport immigration checks, and photo apps that automatically sort pictures by person all rely on this same principle.

That said, face recognition tends to make mistakes in dim lighting, when someone is wearing a mask, or when the face is at an odd angle, and there have been persistent concerns that error rates vary by race and age. Because of this, countries continue to debate how far this technology should be allowed to be used.

If your smartphone has a face-unlock feature, try turning it on and testing it with and without glasses, or in dim lighting, to see if the recognition rate changes. If your photo app has a feature that automatically groups pictures by person, you can also check how accurately it groups photos of the same person taken from different angles.