Using Watermarks to Combat Piracy

TheEvilOverlord writes to tell us PC Advisor is reporting that researchers at the Fraunhofer Integrated Publication and Information Systems Institute have developed a new watermarking system to help track and combat piracy. From the article: "The system lets content providers, such as music studios, embed a watermark in their downloadable MP3 files. Watermark technology makes slight changes to data in sound and image files. For instance, the change could be a higher volume intensity in a tiny part of a song or a brighter colour in a minuscule part of a picture. Even the best-trained human eyes and ears, according to Kip, can't detect the change."

Comments

Defeating?

[Anonymous Coward]

...and in order to defeat such a wonderful scheme, all you have to do is re-watermark the image/music/video.

I've yet to see a scheme that reliably survived that test unless it was specifically designed just for that test (like embedding high power signal in several random places), and upon detection, looking for that signal in those random places (hope is that 2nd watermarking didn't wipe out -some- signal data).

In any case, Watermarking doesn't work! Even Microsoft's researchers said so (damn, can't find link).

Re:Short memories -- this was called SDMI

[Fnord666]

Another problem that I've always had with these systems is the proof issue. If the RIAA tries to prosecute you for having watermarked files, they have to demonstrate the watermark. I can't imagine how they could show that without revealing exactly how the watermark is detected -- and once they do that, you should be off to the races.

This is exactly what "zero knowledge" proofs are supposed to be able to do. Using such a protocol allows me to prove to anyone interested that I know something without revealing what that something is. the proof does not impart any new knowledge to the person/entity that is receiving it about the information. In this context it would mean that the RIAA would be able to prove that the files had been watermarked using their private mark and were thus their copyrighted material without revealing any information about how that watermarking was done. The proof would not rely on revealing the method. Graph isomorphism is a commonly used example.

I don't know if anyone has incorporated a practical application of this into any sort of watermarking scheme, but it could be used for this purpose.