Re:Encoding Data in Dubstep Drops
by GuB-42 on Friday January 15, 2021 @05:24PM
(#25797338)
Not really, unless you are doing a 1:1 digital copy, frequencies outside the range of human hearing are often removed.
Frequencies outside the range of a speaker are often filtered out as it can create distortion or even damage. And the job of lossy compression is to remove everything that you can't hear in order to save bytes, and limiting the bandwidth to what you can hear is the most basic step.
Instead, DRM systems typically encode data over a wide range of frequencies (spread spectrum), well within the audible range. It is designed in such a way that you could hear it in theory, but don't notice it because it blends with background noise. It is very robust, resisting compression, recording and even deliberate attacks. In fact, it is one of the techniques used by the military radios to resist jamming.
Frequencies outside the range of a speaker are often filtered out as it can create distortion or even damage. And the job of lossy compression is to remove everything that you can't hear in order to save bytes, and limiting the bandwidth to what you can hear is the most basic step.
Instead, DRM systems typically encode data over a wide range of frequencies (spread spectrum), well within the audible range. It is designed in such a way that you could hear it in theory, but don't notice it because it blends with background noise. It is very robust, resisting compression, recording and even deliberate attacks. In fact, it is one of the techniques used by the military radios to resist jamming.