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Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

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Re: Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

#71

Post by cma »

baddox wrote: post #61
fipple wrote: post #60

Earlier quoted context omitted.

I don’t know about the techniques but the theory isn’t prima facie impossible. A paintbrush can act like a microphone just like anything else, and if the paintbrush (more likely a putty knife or more rigid object) picked up a sound while applying paint, that could manifest in the paint layer.

And...someone was saying “blue” the instant they applied the blue paint? That’s certainly not impossible to believe, it just seems like a bit of a stretch.

The paper is behind a paywall, but perhaps it was done as a test and not on an actual artifact. Seems doubtful though.

Article is behind a paywall:

https://ieeexplore.ieee.org/document/1449244/?arnumber=14492...

Re: Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

#72

Post by rootsudo »

cma wrote: post #71
baddox wrote: post #61

Earlier quoted context omitted.

And...someone was saying “blue” the instant they applied the blue paint? That’s certainly not impossible to believe, it just seems like a bit of a stretch.

The paper is behind a paywall, but perhaps it was done as a test and not on an actual artifact. Seems doubtful though. Article is behind a paywall: https://ieeexplore.ieee.org/document/1449244/?arnumber=14492...

"First Example This consisted of a pdifine clay. hand thrown on a potter’s wheel. The wheel in this example was an old. student-made wheel, constructed of an automobile crankshaft and flywheel mounted in a (too) light wooden frame. Persistently out of alignment, the wheel had a noisy vibration almost amounting to.a chatter. The pot produced on this wheel was fired at low temperatures. When the pot was suitably mounted on thephono turntable and against the side of the revolving pot was held the phono cartridge (fitted. in this instance. with a “needle” consisting of a flat-ended sliver of wood threequarters of an inch long) the low-frequency chatter sound could be heard in the earphones. "

Re: Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

#73

Post by StanislavPetrov »

>In one set of experiments, they were able to recover intelligible speech from the vibrations of a potato-chip bag photographed from 15 feet away through soundproof glass.

Its hard enough to discern intelligible speech from many people who are standing right in front of you.

Re: Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

#75

Post by nickpsecurity »

PowerfulWizard wrote: post #19
PeterisP wrote: post #14

Earlier quoted context omitted.

"Will you only speak of sensitive subjects in rooms with no windows" - yes, the building standards for secure facilities (i.e. a room where discussing classified information above a certain grade is permitted) mandate no external windows, and much more than that.

I tried to look this up, info here: https://www.dni.gov/files/NCSC/documents/Regulations/Technic... (Ch. 3 sec. F, pg. 13) F. SCIF Window Criteria 1. Every effort should be made to minimize or eliminate windows in the SCIF, especially on the ground floor. 2. Windows shall be non-opening. 3. Windows shall be protected by security alarms in accordance with Chapter 7 when they are within 18 feet of the ground or an acce…

There's also the room in a room concept where one is suspended inside the other. You might add things like ultrasound masking or blocking, too, since it was a known attack vector. From there, I thought about, but can't recall if implemented, some double doorway with buffer in between so opening a door didn't leak sounds/signals. Open one, go in, close it, and then go through other.

Re: Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

#77

Post by nickparker »

namibj wrote: post #62
Sharlin wrote: post #38

Earlier quoted context omitted.

And it is why mechanical shutters are still a thing in dedicated cameras. It is still much faster to move two pieces of metal or carbon fiber over the sensor than it is to read out a multi-megapixel CMOS sensor. When shooting video mechanical shutters cannot be used so the rolling shutter effect can cause artifacts such as fast-moving subjects appear slanted.

Err, modern global shutters like those made by CMOSIS/ams are _much_ faster than that. Their fast one is an APS-C sensor with 4k*3k Px, a shutter closing time of 1s/~120000 and a minimum shutter open time of ~1s/50000. The shutter closing time might be even faster, just reconstruction from frame overhead time values I remember, and adjusting for the share the row skew had. Check the datasheet if you like to. If you k…

Could you expand on or link the bit about time of flight trickery in fog or rain?

c * 1 s / 50,000 is still kilometers, so I’m not sure I understand how this shutter can do what sounds like using time of flight to selectively illuminate stuff at a specific depth

Re: Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

#78

Post by jayd16 »

jetrink wrote: post #63
baddox wrote: post #61

Earlier quoted context omitted.

And...someone was saying “blue” the instant they applied the blue paint? That’s certainly not impossible to believe, it just seems like a bit of a stretch.

Maybe it was painted by Bob Ross?

"And the next word we recovered is....another instance of 'happy'. Are we sure the machine is working?"

Re: Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

#79

Post by Sharlin »

namibj wrote: post #62
Sharlin wrote: post #38

Earlier quoted context omitted.

And it is why mechanical shutters are still a thing in dedicated cameras. It is still much faster to move two pieces of metal or carbon fiber over the sensor than it is to read out a multi-megapixel CMOS sensor. When shooting video mechanical shutters cannot be used so the rolling shutter effect can cause artifacts such as fast-moving subjects appear slanted.

Err, modern global shutters like those made by CMOSIS/ams are _much_ faster than that. Their fast one is an APS-C sensor with 4k*3k Px, a shutter closing time of 1s/~120000 and a minimum shutter open time of ~1s/50000. The shutter closing time might be even faster, just reconstruction from frame overhead time values I remember, and adjusting for the share the row skew had. Check the datasheet if you like to. If you k…

Yes, global shutters are a thing in expensive professional video cameras. But almost every camera in the world is a phone camera prone to rolling shutter effects both in stills and video shooting. Out of the rest, almost all have mechanical shutters for stills shooting and electronic rolling shutter for video. It’s going to be a while before global shutters become a thing in consumer cameras.

Re: Algorithm recovers speech from a potato-chip bag filmed through glass (2014)

#80

Post by buth_lika »

fipple wrote: post #60
jwilk wrote: post #45

Earlier quoted context omitted.

> [Jones] claimed to have extracted the hum of the potter's wheel from the grooves of a pot, So far so good... > and the word "blue" from an analysis of patch of blue color in a painting. What the hell?

I don’t know about the techniques but the theory isn’t prima facie impossible. A paintbrush can act like a microphone just like anything else, and if the paintbrush (more likely a putty knife or more rigid object) picked up a sound while applying paint, that could manifest in the paint layer.

Maybe one could start with making and painting things, while blasting super loud sound at them, and do it with a robot so the only difference is the sound. Then check if the difference between sounds and no sound can be detected in any way right after the thing is done.

If you get any results, just a reproducible blip, then try things you haven't made yourself in a controlled environment... but if you can't even get it there, it seems kind of pointless to mess around with really old things.

That's my layman armchair perspective anyway, but from the armchair it makes sense :D

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