Re:Zoom rolled their own encryption scheme, transmit keys th...
by sdenton4 on Friday April 03, 2020 @09:50PM
(#22775551)
For audio, you don't want to send a wav file over the line, as it's incredibly wasteful. Once it's reasonably encoded, you necessarily end up with a lower entropy steam... So should still have some version of "solid blocks of color", especially for silence. (Exact details depend on the codec, though.)
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Re:Zoom rolled their own encryption scheme, transmit keys th...
by barrkel on Friday April 03, 2020 @10:06PM
(#22775611)
Lossy compression reduces entropy, I'd expect fewer repeats and more of what looks like random data in any compression worth its salt. Thomas also mentioned AAC, not PCM. I agree on the silence, but it would come up as smaller packets, not repeated packets, IMO. And then we're back to timing analysis of speech.
Re:Zoom rolled their own encryption scheme, transmit keys th...
by killjoywashere on Friday April 03, 2020 @10:54PM
(#22775846)
> Lossy compression reduces entropy, I'd expect fewer repeats and more of what looks like random data in any compression worth its salt.
Um, so, just to make sure I understand you, you're implying that lossy compression is not worth its salt? Because you will surely have more repeats in a lower entropy space.
Re:Zoom rolled their own encryption scheme, transmit keys th...
by tptacek on Saturday April 04, 2020 @12:06AM
(#22776128)
You get essentially no repeats (collisions, more precisely) in the AAC streams I played with. Some block boundary headers; that's it.