Digital Watermarks Hide Data, Identities inside Songs

The same technology that may someday reduce illegal copying of music may also deliver extra content and features, such as pictures and liner notes. And these tough, new digital watermarks are really built-in, able to persist through analog re-recording -- and even to survive the degradation of being broadcast over the radio.

SunnComm Technologies and Stealth MediaLabs recently announced the creation of a "super watermark" technology for embedding information inside music files. Originally intended to strengthen copy protection and help catch commercial music pirates, the companies have realized that the same technology can also deliver bonus information inside the music files.

The new technology encodes binary data inside the stereo audio signal itself, "taking advantage of acoustical properties and human hearing characteristics to make it imperceptible to the listener," according to a March 20, 2003 report in C|Net. Having the extra information interwoven in the audio makes it hard to remove without changing the way the music sounds.

Hilary Rosen, the outgoing President of the RIAA (industry trade group), believes the technology is not quite ready for prime time, but that it has promise. The first application is likely to be putting individual identifying numbers on copies of advance-released CDs sent to reviewers, to restrain them from putting their pre-release copies on the Internet to scoop everyone else before a official release date.

Visit the company web sites of SunComm and Stealth MediaLabs 

Read coverage in c|net (March 20, 2003) and Yahoo Business News (March 18, 2003)