Apple's face recognition is included in the iOS 5 application programming interface (API) so app developers can add face-chasing features to their games and apps.
Facial recognition is based on algorithms that identify when a face appears before the camera, by recognising the appearance of eyes and a mouth. The software can then track the face as it moves and apply different effects. It can even distinguish between different people, recognising you and your friends by your fabulous phizzogs.
Face detection and recognition has been around for years in digital cameras, and can track subjects and make sure the camera is focused and exposed correctly for a face. In recent years, the technology has evolved to cope with people wearing glasses or faces turned in profile.
Apple's face-chasing tech is based on Polar Rose, a Swedish company we wrote about back in 2007. The goal of Polar Rose was to index photos on the Web, making it possible to search for pictures of people online even when they had no text identifying who they were. That sounds cool, but sadly that service ended when Apple snapped up the company for around £13m in 2010.
9to5Mac reports on two APIs: CIDetector, which processes images for face-spotting, and CIFaceFeature, which spots eyes and mouths.
Apple's funny Photo Booth app lets you apply kooky special effects to your face on the iPad. Facebook also has face detection built-in, recognising your friends and automatically tagging them in your snaps. It's a very cool feature, but Facebook landed in hot water for turning the service on without telling anyone.
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