Algorithm can reconstruct speech from a pack of chips through soundproof glass
Very interesting tech. The ability to recover sound by bouncing a laser off of glass has been around for ages, this is different as it just uses a camera and would therefor be difficult to detect. You find a boundary, for example, between a blue and red object. Blue and red combine to make purple, and by watching how it shifts around purple you can reconstruct information.
It isn't easy. An ideal setup would have a camera that could record 2,000 to 6,000 frames per second (FPS), which is damn fast and requires a LOT of light: as the FPS goes up, so does the amount of light for a proper exposure. The real breakthrough by the researchers was to find a quirk in cell phone cameras, which top out at about 60 FPS but this glitch can be exploited to provide the same information.
The defense? Close the drapes.
Their findings will be presented at the Siggraph conference.
http://newsoffice.mit.edu/2014/algorithm-recovers-speech-from-vibrations-0804
It isn't easy. An ideal setup would have a camera that could record 2,000 to 6,000 frames per second (FPS), which is damn fast and requires a LOT of light: as the FPS goes up, so does the amount of light for a proper exposure. The real breakthrough by the researchers was to find a quirk in cell phone cameras, which top out at about 60 FPS but this glitch can be exploited to provide the same information.
The defense? Close the drapes.
Their findings will be presented at the Siggraph conference.
http://newsoffice.mit.edu/2014/algorithm-recovers-speech-from-vibrations-0804