#visual microphone

[verdiprati]

whoa

[thoughtportrait]

Optical Microphone Developed by CMU Researchers Sees Sound Like Never Before

Mark Sheinin (left) and Dorian Chan were part of a CMU research team that developed a camera system that can see sound vibrations with such

A camera system developed by Carnegie Mellon University researchers can see sound vibrations with such precision and detail that it can reconstruct the music of a single instrument in a band or orchestra.

Even the most high-powered and directed microphones can't eliminate nearby sounds, ambient noise and the effect of acoustics when they capture audio. The novel system developed in the School of Computer Science's Robotics Institute (RI) uses two cameras and a laser to sense high-speed, low-amplitude surface vibrations. These vibrations can be used to reconstruct sound, capturing isolated audio without inference or a microphone.

"We've invented a new way to see sound," said Mark Sheinin, a post-doctoral research associate at the Illumination and Imaging Laboratory (ILIM) in the RI. "It's a new type of camera system, a new imaging device, that is able to see something invisible to the naked eye."

The team completed several successful demos of their system's effectiveness in sensing vibrations and the quality of the sound reconstruction. They captured isolated audio of separate guitars playing at the same time and individual speakers playing different music simultaneously. They analyzed the vibrations of a tuning fork, and used the vibrations of a bag of Doritos near a speaker to capture the sound coming from a speaker. This demo pays tribute to prior work done by MIT researchers who developed one of the first visual microphones in 2014.

[sodman2k]

The Visual Microphone: Passive Recovery of Sound from Video by: Abe Davis Michael Rubinstein Neal Wadhwa These clever cats have built an algorithm that is capable of recovering sound from video - They can film objects (like the chip packet demonstrated) that respond to vibration with a high speed camera and recover the sound that was happening around it. Oh, and they've worked out how to get a similar effect from shitty cameras with rolling shutters. Wow.

[thebeakerblog]

Watch: Eavesdropping on Speech By Videotaping a Bag of Potato Chips

When sound hits an object, it causes vibrations. Normally, these subtle visual signals are invisible to the human eye, but they're not invisible to high speed cameras. That raises an interesting question: What if you could videotape sound vibrations, feed them into a computer, and translate them back into sound? 

 Watch the explanation here:

It's a phenomenon the scientists say could transform many objects into "visual microphones," which could be used for everything from high-tech surveillance to forensics. 

[sweetthingshavesharpteeth]

Recovering audio from video. Want to hear stuff on the other side of soundproof glass? No problem!

[lkrory21]

The Visual Microphone: Passive Recovery of Sound from Video

//Scientists Extract Audio From Video Of Vibrating Objects//

[skunkbear]

MIT researchers have reconstructed the sound of speech by analyzing a high speed video of the minute vibrations of a nearby chip bag. They reconstructed "Mary Had A Little Lamb" from the vibrations of the leaves of houseplant. They reconstructed Queen's "Under Pressure" from a video of earbuds. That's a cool trick (with some interesting surveillance and forensic implications).

"This is totally out of some Hollywood thriller," says Alexei Efros, an associate professor of electrical engineering and computer science at the University of California at Berkeley. "You know that the killer has admitted his guilt because there’s surveillance footage of his potato chip bag vibrating.”

If you want to really see sound waves check out our video.