Voice inversion is a primitive method of rendering speech unintelligible to prevent eavesdropping of radio or telephone calls. I wrote about some simple ways to reverse it in a previous post. I've since written a software tool, deinvert (on GitHub), that does all this for us. It can also descramble a slightly more advanced scrambling method called split-band inversion. Let's see how that happens behind the scenes.
http://www.windytan.com/2017/09/descrambling-split-band-voice-inversion.html
(Score: 2) by bzipitidoo on Sunday September 17 2017, @01:26PM (1 child)
Yeah, inversion sounds like the ROT13 of the analog audio world.
(Score: 3, Interesting) by Hyperturtle on Sunday September 17 2017, @01:58PM
The privacy lock on my girlfriend's Hello Kitty clear plastic storage box that she's kept since she received it as a child, also conferred no real protection against spying corporate interests and government agencies intent on learning her secrets.
Despite this, it prevented her younger siblings from casually, or quite specifically due to the desired intent, of reading her diary. The diary itself also had a simple tiny warded lock on it that could be defeated with a bent piece of metal (like a paperclip).
However, sometimes, simple means of obfusciation keeps honest people honest, and meddling kids from being able to make things worse, even if they explicitly had intended to not be honest.
Not that they would be scheming to use this tool to break a spread spectrum audio tool used by lovestruck teenagers to secretly confer their love to one another--but there are lots of free apps to spy nowadays, and lots of apps are spying anyway.
Some level of obfusication makes the effort harder and might not be worth bothering with.
Until someone writes a tool like this that makes it easier to defeat, of course.