A top university in China is using a facial recognition system to verify the identity of students and staff members entering its campus.

Anyone going through the southwestern gate of Peking University can now have their face scanned by a camera instead of showing their ID card to security guards under a trial run of the system that started on Wednesday. The technology will be installed at all university gates soon.

Some top universities in China restrict the public from visiting their campuses, and students and staff are often required to show proof of identity before they can enter.

Unlike the one-on-one recognition technology used at some railway stations－where an identification card is placed on a device that compares the photograph on the card to a real-time scan of the passenger's face－the system at Peking University searches through hundreds of thousands of photos in a database to match a scanned facial image, according to the school's Sina Weibo account.

The system currently uses the university ID photos of its students and staff. Photos can be retaken in the guard room near the gate if the pixels of photos on the university IDs do not quite match what is required for facial scans, the microblog posting said.

It also said that since the camera is installed outdoors, images may be overexposed during the day or underexposed at night, which could lead to failed facial recognition.

This is not the university's first use of the technology on campus－it has already installed more than 20 facial recognition devices outside some of its libraries, classrooms, student dormitories, gymnasiums and computer centers.
Zhang Bei, director of the university's computer center, which developed the system, said it usually takes about two seconds for an image to go through the system. The center is working to improve its accuracy and speed, she said.

All future candidates for admission to the university will be required to provide a cellphone selfie that has not been modified by photo software.

The key to making the system better is photos that reflect exactly how people look, she said.

Zhuang Chen, a second-year graduate student at Yenching Academy in the University, said the system is quite convenient and interesting, especially when he forgets to bring his student ID card.

Facial recognition takes more time than getting a student card checked by guards, he said. "However, once you get the hang of the system and stand at the appropriate distance from the monitor, the system works much faster."

Liang Yiming, a second-year student at the law school, said the system makes her feel safer because it prevents third parties from using a student's ID card to enter the school.