The Visual Microphone: Passive Recovery of Sound from Video
The Visual Microphone: Passive Recovery of Sound from Video on HackerTube: recommended by 1 Hacker News commenter across 1 month, 2015–2026.
MIT researchers show that sound can be recovered from silent video by analyzing tiny vibrations in objects such as a potato chip bag. It works even with consumer cameras by using rolling shutter.
What HN commenters said
6 Hacker News comments link this video. Each one links back to its thread.
eesmithDec 2017Recommends
"security cameras outside of stores" would be in public areas, yes? The Lifehacker link you pointed to says "Generally speaking, you have the right to record video in all public spaces without need of consent." Now for the fun part - it can be possible to extract audio from video, by careful processing of the small motions the sound induced in objects in the frame. See ▶ this video . High-speed camera is best, but at the end they show how a regular consumer-level camera can also be used.
in “Prostitution cases dismissed because cops’ cameras mistakenly recorded audio” · View on HN
spyderFeb 2026Cites it
with a high speed camera any vibrating reflective object like a potato chips bag can become a microphone: ▶ this video
in “WiFi Could Become an Invisible Mass Surveillance System” · View on HN
bbbobbbJul 2020Cites it
Here similar experiment, 6 years ago: ▶ this video If you think that actual government agency cannot do even more easily with better equipment in 2020 you're kidding yourself.
in “Spies can eavesdrop by watching a light bulb's vibrations” · View on HN
ehsankiaOct 2018Cites it
You can do it with video too, even: ▶ this video Also, this is only tangentially related, but you can also see through walls using WiFi: [link]
in “Show HN: Lipreading with Deep Learning” · View on HN
anfractuosityJan 2018Cites it
See this - ▶ this video They show audio captured from a 60fps video from a DSLR exploiting the rolling shutter. I'm not sure if you can use less than 60fps though?
in “If you watch closely enough, everything is a speaker” · View on HN
lawryMar 2015Cites it
Remember even if you mute your microphone, it's still possible to extract audio from the video you are streaming: ▶ this video
in “Periscope by Twitter” · View on HN