8 ms·
Candy Wrappers Are Listening (2014)
- simooooo 9y agoMy bullshit meter just exploded.
- larkeith 9y agoThe paper can be found at [1]. Did you have a specific grievance with their procedure/conclusions, or just baseless cynicism? [1] https://dspace.mit.edu/handle/1721.1/100023 https://dspace.mit.edu/handle/1721.1/100023
- hodl 9y agoYour bullshit meter is too sensitive.
- dang 9y agoYou've posted a lot of unsubstantive comments to Hacker News. We eventually ban accounts that do that, so would you please stop? The idea here is as follows. If you have a substantive point to make, make it thoughtfully; if you don't, please don't comment until you do. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- blt 9y agoBill Freeman, the PhD supervisor on this project, is a really creative computer vision researcher. Read through his CV, he has a great ability to pick interesting problems slightly outside the mainstream. I wish for that ability.
- tristanj 9y agoFun tidbit: Three letter intelligence agencies have known about this attack vector since before this paper was published, and are worried it could be exploited in the wild. https://www.theguardian.com/world/2013/aug/20/nsa-snowden-files-drives-destroyed-london https://www.theguardian.com/world/2013/aug/20/nsa-snowden-fi... [British government officials] expressed fears that foreign governments, in particular Russia or China, could hack into the Guardian's IT network. But the Guardian explained the security surrounding the documents, which were held in isolation and not stored on any Guardian system. However, in a subsequent meeting, an intelligence agency expert argued that the material was still vulnerable. He said by way of example that if there was a plastic cup in the room where the work was being carried out foreign agents could train a laser on it to pick up the vibrations of what was being said. Vibrations on windows could similarly be monitored remotely by laser.
- Judgmentality 9y agoI've actually done this in a lab with a laser - it's a fun trick. What the original article talks about though is passively measuring sound from objects using a camera - no laser. Although they're measuring the same thing (physical vibrations of objects) the way they're doing it is actually quite different.
- petertodd 9y agoA friend of mine used that technique while working in an entomology lab studying the mating habits of cockroaches. They were trying to figure out what kinds of vocalizations the cockroaches were making while mating, and bouncing a laser off their shell was by far the easiest way to record those very quiet sounds. It's been a few years, but I think this was the manufacturer: https://www.polytec.com/us/vibrometry/products/ https://www.polytec.com/us/vibrometry/products/ I wouldn't be surprised if the non-laser techniques eventually also show up as off-the-shelf products too, simply to reduce costs - a simple camera could be cheaper than a laser, and might have advantages in being able to record sounds off multiple points at once.
- slazaro 9y agoAlso, I think a big advantage for the camera-based solutions is that they're totally passive, while laser-based need to interact with the object.
- Zigurd 9y agoTo make a camera-based solution practical, it seems like one would neeed a specialized camera, for modest resolution, but very high frame rate. Without enough frame-rate, you can't capture high frequencies. Even if speech could be discerned from a spectrum that rolls off at 300hz, well under the peak energy of a typical human's speech, you would still need many hundreds of frames per second.
- fisherjeff 9y ago
- joecool1029 9y agoLaser vibrometers are neat. They can also be used to sniff keystrokes remotely by pointing them at a laptop lid. Research also released before this paper.[1] [1]https://www.youtube.com/watch?v=xKSq9efXmh8 https://www.youtube.com/watch?v=xKSq9efXmh8
- larkeith 9y agoThe linked article describes a passive monitoring system achieving the same result, no laser required.
- larkeith 9y agoFor more details, full paper can be found at https://dspace.mit.edu/handle/1721.1/100023 https://dspace.mit.edu/handle/1721.1/100023
- sopooneo 9y agoI'm assuming it would need to be extremely high frame rate video to extreact decipherable voice data. Because even at 60 frames per second, which I understand is at the high end for normal video, that gives you a maximum frequency of only 30Hz, which is nearing the low end of human perception. So it's interesting and a definite risk if an attacker is supplying their own camera, but definitely does NOT mean you can pull voice data from the vibrating tablecloth in a YouTube video, right?
- craigds 9y agoDepends what's on camera and how smart your software is. A full wavelength of audible sound is between a few centimetres and a few tens of metres. If you have a few objects in scene at such known distances, you can calculate how far out of phase they are, interpolate them and piece together a much higher effective sampling rate.
- KnightOfWords 9y agoThey show a technique which exploits the rolling shutter effect to recover frequencies at up to five times the frame rate. On the other hand, they also mention that artifacts in highly compressed video stop their techniques from working, so any secrets in your YouTube vids are probably safe.
- function_seven 9y agoNot from a YouTube video, due to the video compression obliterating the small details needed to get the frequency. But the article notes that a rolling shutter allows even a 60fps camera to capture higher frequencies. Each scan line of the captured video is at a sub-frame time slice. If the object occupies a hundred scan lines, then you have 100 slightly shifted 60 hz samples that you can combine to reconstruct higher frequencies.
- Bitcoin_McPonzi 9y agoDid you read the article? There are tricks you can do that leverage how a rolling shutter works so you can get an effective high framerate across a small area of the image.
- matte_black 9y agoWhat is a viable defense against this attack? Some kind of white noise machine?
- azernik 9y agoA private windowless room.
- draw_down 9y agoCould have a hidden camera.
- 0xdeadbeefbabe 9y agoSkype with headphones and a keyboard for the secret stuff?
- matte_black 9y agoYou can point a laser at a keyboard and log the keystrokes, probably can do the same by pointing one at a headphone.
- regularfry 9y agoAbstain from candy. And coke. And checks article again bricks.
- spyder 9y agoEven more "scary" (if it really works): using reflected microwaves in a windowless room in a similar way: https://www.eetimes.com/document.asp?doc_id=1274746 https://www.eetimes.com/document.asp?doc_id=1274746
- titzer 9y agoAlso a really cool application of this rolling shutter is video of guitar strings: https://www.youtube.com/watch?v=8YGQmV3NxMI https://www.youtube.com/watch?v=8YGQmV3NxMI (Note that real guitar strings don't vibrate in this way; they vibrate across their entire length, with limited higher order harmonics; the visible waveforms here are an artifact of the CCD capture process).
- thedrake 9y agoThis will help to solve debates like the one about the moon landing. Use this video (https://www.nasa.gov/multimedia/hd/apollo11_hdpage.html https://www.nasa.gov/multimedia/hd/apollo11_hdpage.html - the highest HD I could find) of the flag moving and extract sound. Then extract the sound (if there is any) http://people.csail.mit.edu/mrub/vidmag/ http://people.csail.mit.edu/mrub/vidmag/ is the site that he mentions at the end or the ted talk given that goes into more about the workflow. Not a programmer so not sure how to use the code to implement it. Any takers?
- Sir_Cmpwn 9y agoThis is going to do nothing to solve the "debate". Moon landing deniers will find an excuse to dismiss this evidence like they have for the rest.
- jwilk 9y agoThe conspirators purposefully made the flag from nylon, rather than candy wrappers, in order to foil future attempts of sound extraction.
- 333c 9y agoAm I missing something? Wouldn't there be no sound to extract because the moon has no atmosphere? Or maybe that's your point — if it were faked, there would be sound, otherwise not.
- mikejmoffitt 9y agoAs the original footage was done on film, the time difference between the top and bottom of a single frame is zero, unlike a "rolling shutter" progressively scanned sensor. The framerate is also much lower than the 60fps phone camera used in the last example from the MIT video, which was only barely enough to get meaningful data out. So unfortunately, we probably won't be using this to get much out of old traditionally archived footage - not because of resolution of the frame, but time resolution.
- amelius 9y agoIf smartphone accelerometers become more advanced, perhaps they can be used in the same way :)
- delinka 9y agoI'm trying to work this one out in my head ... You've left a smartphone lying around and you want to read accelerometer data to determine what was said in proximity. Just turn on the mic instead. You've left a smartphone lying around to remotely read light bouncing off it ... accelerometer not required. Also, just turn the mic on instead.
- breakingcups 9y agoI wonder how much archival footage we might be able to give a second look knowing what we know now.
- 0xdeadbeefbabe 9y agoWell fine, but who do you listen to? Is face to face interaction still a thing?
- mcknz 9y agosee also https://news.ycombinator.com/item?id=8131785 https://news.ycombinator.com/item?id=8131785
- mmagin 9y agoI thought this was as old as continuous-wave lasers, albeit the original idea was bouncing it off a window.
- efader 9y agocreepy