Scientists Can Now Eavesdrop By Watching a Soundless Video of a Glass of Water
Source: smithsonianmag.com
Sound is pressure, pressure causes motion and motion shows up on film
Sound is pressure. Both the blare of a trumpet and softly spoken words are just waves passing through the air. When those waves hit your eardrum, they’re interpreted as sounds. But when they bounce off other objects—say a bag of chips—they make the bag’s thin foil wiggle. Using high-speed video and advanced imaging algorithms, computer scientists have figured out how to reverse engineer the gentle flapping of a chip bag to figure out the sounds that set it in motion.
These vibrations are tiny. They’re fast. They’re all but imperceptible. But they exist, and in the video above from MIT PhD student Abe Davis you can see how researchers reproduced musical notes and human voices from these minute motions captured on video. The technique, which Davis dubbed a “visual microphone,” can even work with a regular video camera.
The research raises the specter of all sorts of science fiction possibilities: who needs to read lips or plant recording bugs when you can just lift a conversation off a nearby snack bag?
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Read the full article at: smithsonianmag.com
Google Chrome browser can be subverted to eavesdrop on conversations happening around it
