U.S. tech giants and Chinese state-backed companies showed off the future of policing in this southern technology hub as they vie for a slice of the world’s biggest surveillance market. Companies from across the globe packed one of the world’s biggest surveillance trade shows to demonstrate the latest gizmos and algorithms powering the high-tech revolution in the industry, of which China is on the vanguard. Tools being hawked included facial-recognition cameras, iris scanners, software that can read a subject’s

mood and cameras that can scan license plates in the dark. The surveillance-equipment market in China was valued at $6.4 billion last year, according to IHS Markit . China is a big buyer of surveillance technology as Beijing steps up its efforts to better monitor its 1.4 billion people. That is providing a boon for equipment makers, who are looking to export their gear abroad. But it has also sparked concern from rights activists about how the authoritarian government is using the souped-up “Big Brother” technology. CONTINUE