TikTok added an “Image and Audio Information” section to its U.S. privacy disclosures Wednesday. The update might shed some light on how the popular song and dance app’s “For You” recommendations dazzle users with videos that are uncannily tailored and personal.
The latest disclosures give a fascinating, suggestive glimpse into the inner workings behind the black mirror of users’ smartphone screens.
Users already knew they were sharing their image and voice with TikTok to broadcast, or serve to followers of accounts set to private. But now TikTok is clueing them in to some of the technical aspects of the magic-making that allows the app “to enable special video effects” and serve content based on “demographic classification” through machine learning:
“We may collect biometric identifiers and biometric information as defined under US laws, such as faceprints and voiceprints, from your User Content.”
The short policy update doesn’t elaborate further, but as long ago as 2012 (ancient history in Moore’s Law years), MIT researchers showed off how smartphone cameras (with far less sensitive lenses than today’s standard) can measure your heartbeat just by looking at your face, through a process called “Eulerian Video Magnification.”
Does this kind of biometric reading of users’ videos violate U.S. law? Not at the moment. Even the strongest biometric privacy protections in the United States, under Illinois BIPA, mostly apply to employers, not consumer apps, according to the National Law Review.
Why It Matters: An app with enough server power on the back-end, wieldy deployment of your smartphone’s sensors, and a deep comprehension of human biometric markers, can do more than just see you. It can read your mind–– the way poker players or expert forensic psychologists read and evaluate the subjects of their inquiries through visual cues. Users aren’t merely delighting each other. They’re part of a global collaboration, unprecedented in capability and scale, to understand themselves at deeper level than was ever possible until very recently.