Data Transmission Via Hard Rock Is Now Possible

By now most of us have heard of or experienced audio watermarking, where metadata is hidden inside the audio signal so the artist, song, record label, publisher and songwriter can be identified when it’s played. That’s been around for at least 20 years, but the idea has been taken to another level by 2 PhD students at the Swiss Federal Institute of Technology in Zurich to actually transmit data via the over-ear audio experience of a song.

We all know that a growing amount of metadata is inserted in every song found online, and that’s necessary so the artists and writers can get paid. In the case of “audio steganography,” the official name for the field of secretly embedding data in a piece of audio, the data is hidden within the music so that the ear can’t hear it, but any device with the necessary hardware/software can decode it.

The data is transferred in about 400 bits per second, which is pretty slow. Error correction takes up 200 of those bits, which then leaves enough for about 25 letters or characters. Doesn’t sound like much, but it could be enough for the length of a wifi password, a website URL or a short message.

The most obvious places to use this technology is in places where music is always playing, like department stores, hotel lobbies or transportation hubs. For instance, the background music at a hotel could contain passwords for the local Wi-Fi network giving guests access without having to enter a password. Spying is another obvious possibility, although since the data isn’t encrypted it would probably only have short-term value.

So where does the hard rock fit in? The scientists discovered that the technology works best embedded into songs that were loud, with Van Halen, Scorpions and Metallica working best in their tests. Some pop music also works, but genres with lots of dynamics like jazz and orchestral probably aren’t candidates.

All that said, audio steganography probably does have some future in our current tech world, since we all carry a smartphone with a speaker and microphone. You could be receiving embedded music messages sooner than you think.

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