Technology faces up to a question of identity(3)

Once this is done, the computer can see and recognize each student.

"This system suits the classroom, which is a relatively closed environment and not many unfamiliar faces will enter. For open public spaces, the facial recognition will be far more complex," Wei said.

These are obvious applications for those manufacturing systems to prove attendance in areas bigger than classrooms, said Xing Peng, marketing manager at Hanvon, a recognition technology company.

"As far as I know, fingerprint technology accounts for around 80 percent of the market, while face recognition only accounts for 15 percent. But the market outlook is promising."

Face-recognition technology is already used by global technology giants such as Google.

In as early as 2011, Google announced it was developing a recognition mobile app that allows users to snap a picture of a friend or new acquaintance, and then access his or her Google Profile contact information.

Chinese search engine giant Baidu also has its recognition service, which allows users to upload a picture and search for all the pictures on Baidu that include a similar face to the uploaded one.