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

Human?

[biocute]

Even the best-trained human eyes and ears, according to Kip, can't detect the change.

Who says anything about using human senses to detect the watermark? If these watermarks are embedded by machine, I'm sure it won't be long until Watermark Bob creates a "cleanser" program to detect anything unusual, and maybe even remove it.

Re:Human?

[Iphtashu Fitz]

I'm sure it won't be long until Watermark Bob creates a "cleanser" program to detect anything unusual, and maybe even remove it.

Good point. All you'd really need is two or more copies of a given file, each with their own watermarks. Do a relatively straightfoward binary diff on the files and you'd quickly spot the watermarks. Normalize the diffs based on the similarities between the multiple file copies, and voila! Instant un-watermarked file.

Re:Human?

[Kadin2048]

The intended use of watermarking, at least as I see it, is less for mass-released files than for prerelease or limited-release uses.

E.g., radio stations get copies of songs weeks before the CDs actually hit stores -- and suspiciously, the songs tend to show up on P2P networks soon after they go out to radio stations. What the music producers would really like to be able to do is trace the leaked files back to whoever put them on the internet, and then get medeival on them for breach of contract.

You can imagine similar uses for prerelease screenings of movies that go out to critics, film review boards, etc. It's less about preventing piracy than it is about finding the snitch afterwards so they can be made an example of. Really, the piracy deterrent is not technological (the watermark), but social (whatever punishment gets inflicted). The watermark is just facilitating the latter.

I suppose in theory if you had a watermark that could be embedded into the file quickly and easily, you could use it on downloaded music (like the iTMS) to see if people were sharing files that they purchased, but really I think systems like this are designed to catch big fish, not Joe Preteen who's ripping files that he bought off of Napster and putting them onto Kazaa.

A lot of similar systems are used with images; actually many of the techniques used for watermarking are used for steganography (it's arguable that watermarking is really a form of steganography), like Least Significant Bit padding for one. There are also systems that have a robust enough watermark that they will survive printing and scanning, although they tend to begin to mess up the image slightly.