4 ms·
Can this level of signal be broadcast over TVs? Could this be embedded in an advertisement that triggers a bunch of devices to read from somewhere? I too, eage
by sailfast 9y ago
Can this level of signal be broadcast over TVs? Could this be embedded in an advertisement that triggers a bunch of devices to read from somewhere?
I too, eagerly await the pre-processing software that blocks all inaudible frequencies. Not sure why this was not done in the first place.
- TeMPOraL 9y ago> I too, eagerly await the pre-processing software that blocks all inaudible frequencies. Not sure why this was not done in the first place. This won't save you. By the time the signal leaves the microphone and reaches the ADC, it's already in the audible range.
- morsch 9y agoFor most of the tests, they used a dedicated ultrasonic speaker. However, they also tested it with a Samsung S6 Edge controlling an Apple watch; it worked. So you don't strictly need specialized hardware. Whether or not it works for TV depends on the broadcast signal (processing, audio codec) and the playback device speaker. The latter should work out somehow, given that a smartphone speaker can do it. Most audio codecs go up to 44 or even 96 kHz, so the range should be there. But digital TV signals carry lossy audio, designed to save space by throwing away data not discernible by humans. I'm not sure how high the fidelity of AAC is beyond 20 kHz. Should be easy enough to find out.
- lunchables 9y agoHow about a completely inaudible: "Alexa, buy me a leather mask".
- confounded 9y agoOld news! https://arstechnica.com/tech-policy/2015/11/beware-of-ads-that-use-inaudible-sound-to-link-your-phone-tv-tablet-and-pc/ https://arstechnica.com/tech-policy/2015/11/beware-of-ads-th... (Note: Does not require the sophistication of this attack, just the ability to play inaudible sound, mic permissions, and a total lack of regulation.)