Chinese authorities have begun deploying a new surveillance tool designed to identify people by how they walk, or the shapes of their body.

Adding to the already staggering number of surveillance cameras — many of which use bleeding edge optics and facial recognition technologies — China is already using the tool on the streets in its two largest cities, Beijing and Shanghai. It, again, raises concern among privacy advocates about how far the government is willing to go to keep tabs on its citizens.

Huang Yongzhen, CEO of Watrix, the company that designed the system, says it can identify people from up to 50 meters (165 feet), even when their back is turned or their face is covered.

Credit: Associated Press

The tool would fill gaps in current surveillance technology, that needs close-up, high resolution images of a person’s face to work. Watrix requires only a clear view of the person walking, even from the back or side.

“You don’t need people’s cooperation for us to be able to recognize their identity,” Huang told the Associated Press. “Gait analysis can’t be fooled by simply limping, walking with splayed feet or hunching over, because we’re analyzing all the features of an entire body.”

The company has raised some 100 million yuan ($14.5 million) already and is currently being used to thwart petty crime, such as jaywalking, and identify potential fugitives in crowds.

Down the line, security officials say they are developing an integrated national system of surveillance camera data, of which the new gait identification system would be added.

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