Facial Recognition

Facial recognition is used more widely than you would think such as on Facebook to tag photos, by apps to compile albums of people, security cameras, to unlock our mobile phones and even to confirm your identity when making a bank transfer. It is another way of recognising and identifying a human face through technology by using biometrics to map the facial features.

How does it work?

Firstly a computer needs to learn what a face is which is done by training an algorithm. Eventually the algorithm will have mastered the task of facial detection, enabling the system to detect faces in the images captured.

After the face is located the recognition side needs to be done. Just like with fingerprints the system will hold a database of faces that have already been mapped, a unique code created and the information stored. This can include things such as the positioning of features and the distance between them. When a picture of your face is captured by either photo or video, the facial recognition software will read the geometry of the face, map any distinguishing features and check the information against the database.

Some cameras have the ability to add depth to the 2D images presented through a technique called Lidar which stands for Light Detection and Ranging. This technique works by sending out laser lights which reflect off your face and gets picked up by an IR (infrared) camera. This camera measures the time it takes for the reflected light to come back, enabling a depth map to be created.

When this technology is being used in public spaces for security purposes or for surveillance by the police the intended purpose is to identify anyone who is of interest to the police for being suspected of involvement in crimes.

Recent use in public spaces

Facial recognition has come under scrutiny mainly because of the use of live facial recognition in public spaces. Where apps and images uploaded to social media are concerned these acts are done willingly. Where security is involved, the argument is that it is an invasion of privacy, may not be necessary and also that we don’t know what happens with the images captured. A few police forces in the UK have been trialling the technology and have come under scrutiny for doing so for many reasons. Members of the public and campaign groups such as Liberty and Big Brother Watch have raised concerns (and even argued for complete bans on the use of live facial recognition systems in public space over the issue of privacy, what is done with the data captured if no match is made against a person of interest and also the idea of being mistakenly identified as someone who has committed a crime due to the  possibility of mismatches. Campaign groups have even argued for complete bans on the use of live facial recognition systems in public space.

At the moment, there is an absence of clear laws and regulations governing what can and can’t be done with a facial-recognition system despite the use of such technology becoming increasingly more popular.