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Wearable Microphone Jamming

sandlab.cs.uchicago.edu

11–20 of 129 posts

Re: Wearable Microphone Jamming

#11
post #8

Cool research. Given that you are also jamming hearing aids and other microphones, don't think it's practical to be used in real life. Off topic: check out Pedro's other work http://plopes.org/ Definitely thought provoking research :)

Depends of what real life scenario is.

A cafe, maybe not. A meeting room, likely yes. There at least you can declare that a hearing aid is used. The very point of the device is to jam other microphones.

Not going to last very long, though; ultrasound filters will soon appear on all relevant gear, including mobile phones.

Re: Wearable Microphone Jamming

#13

I wonder how sensitive dogs would be to such a jamming system.

Dogs can perhaps hear up to 45,000hz. This emits tones within that range.

Article says at 1 meter the sound is mostly less than 70dB and less than 80dB in hot spots.

So probably not too bad unless I'm missing something.

Re: Wearable Microphone Jamming

#14

Earlier quoted context omitted.

No one is going to buy this. It doesn't jam your voice at all. It introduces enough distortion and noise so that computer speech recognition software gets 4/5 words wrong. Let me make a comparison. Claim: Those capchas with "type in the word you see" have an error rate of 4/5 letters when read by a computer. Yet here we are, humans, reading them just fine. Now, if you're a conspiracy theory fake elected moon landing…

So what is the effect in the first part of the video on the website then? Are you saying they‘ve faked it?

No, I'm saying that does literally nothing but add noise. It does not block or change the original signal in any significant way for human ears - only for consumer-level voice recognition software. Which is extremely crappy even without noise for anything more complex than "hey google play some ads in the middle of this song."

Once you take the noise out, the voice recognition software has problems recognizing the words. People do not. You can take the noise out at home with lots of different software or hardware. Skype/teams/zoom do this on a very basic level by default - as do most microphone audio drivers in windows. Once it's taken out, distortion from the noise is just enough to make the voice recognition miss a bunch of words. Human ears do just fine though.

https://www.youtube.com/watch?v=u3zdGza5zeI

Re: Wearable Microphone Jamming

#15

Interesting trial. But I'm sure there will be techniques to clean the noise out.

I'm wondering too. I had a glimpse at a paper and it seems it works because even though ultrasound is "inaudible to humans, still leaks into the recorded speech due to non-linear amplification of the microphone’s circuit". The chart thought shows the leakage has small dB (-20) in audible spectrum.

Too bad researches didn't leave any samples of recording in the repo. Curious how it would be effective after: 1) filtering frequencies to 0-16kHz 2) getting 1-2sec sample duration of noise profile while nobody speaks and using noise reduction filter from audacity

Re: Wearable Microphone Jamming

#16
post #2

How quickly are they going to go commercial with this?

No one is going to buy this. It doesn't jam your voice at all. It introduces enough distortion and noise so that computer speech recognition software gets 4/5 words wrong. Let me make a comparison. Claim: Those capchas with "type in the word you see" have an error rate of 4/5 letters when read by a computer. Yet here we are, humans, reading them just fine. Now, if you're a conspiracy theory fake elected moon landing…

I’m not worried about the government spying on my individually, the resources to fight that would be impossible

I am worried about large companies spying on me en mass (and selling or leaking that information). That requires automation (voice/face recognition), it’s also reality, not a conspiracy theory, alas I do see it as inevitable and there only so much you can do to fight it.

Re: Wearable Microphone Jamming

#17
post #15

Interesting trial. But I'm sure there will be techniques to clean the noise out.

I'm wondering too. I had a glimpse at a paper and it seems it works because even though ultrasound is "inaudible to humans, still leaks into the recorded speech due to non-linear amplification of the microphone’s circuit". The chart thought shows the leakage has small dB (-20) in audible spectrum. Too bad researches didn't leave any samples of recording in the repo. Curious how it would be effective after: 1) filteri…

Download the audio from the YouTube video at the top of the page - it has a sample in it

Re: Wearable Microphone Jamming

#19
post #11
post #8

Cool research. Given that you are also jamming hearing aids and other microphones, don't think it's practical to be used in real life. Off topic: check out Pedro's other work http://plopes.org/ Definitely thought provoking research :)

Depends of what real life scenario is. A cafe, maybe not. A meeting room, likely yes. There at least you can declare that a hearing aid is used. The very point of the device is to jam other microphones. Not going to last very long, though; ultrasound filters will soon appear on all relevant gear, including mobile phones.

yeah, then the ad tech is just moving onto the next best thing. SDR.

Re: Wearable Microphone Jamming

#20
post #15

Interesting trial. But I'm sure there will be techniques to clean the noise out.

I'm wondering too. I had a glimpse at a paper and it seems it works because even though ultrasound is "inaudible to humans, still leaks into the recorded speech due to non-linear amplification of the microphone’s circuit". The chart thought shows the leakage has small dB (-20) in audible spectrum. Too bad researches didn't leave any samples of recording in the repo. Curious how it would be effective after: 1) filteri…

The idea is that the analogue components are saturated already so there's no available margin for the lower frequencies to further actuate the diaphragm or amplifier.
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