3 ms·
If the watermark is inaudible, can't it removed by re-encoding the audio with a bandpass filter tuned for audible range?
by eigenvector 6y ago
If the watermark is inaudible, can't it removed by re-encoding the audio with a bandpass filter tuned for audible range?
- ithkuil 6y agoInaudible just means that a person can't perceive it, not necessarily because it's outside the frequency range a human ear can sense. A common technique is to add pseudo noise to encode data over the whole audio spectrum. It's related to the spread spectrum techniques used for radio communications resistant to signal degradation (natural or jamming), common in many radio protocols, like your GPS receiver in your phone. https://en.m.wikipedia.org/wiki/Audio_watermark https://en.m.wikipedia.org/wiki/Audio_watermark