Microsoft Patents the Uncrackable Digital Watermark?

InformationWeek has previously highlighted the impressive track record of hackers in getting past digital rights management systems. Now they point out that Microsoft may have developed and patented a truly robust digital watermark for audio files that can resist all (?) efforts to remove it. Good luck, Microsoft!

Microsoft (MSFT) may have just succeeded in giving the lie to claims by anti-DRM advocates that tech and record companies should forget about digital-rights management because they can never come up with something that's totally immune to cracking.

That's because two inventors working in Redmond, Darko Kirovski and Henrique Malvar, have taken concepts from spread-spectrum technology--used by the military for secure radio communications--and adapted them to the task of permanently inserting the owner's (aka content producer's) name within MP3 and .WAV files.

Microsoft was awarded U.S. Patent 7,266,697, entitled "Stealthy audio watermarking," on Sept. 4, for the duo's work.

As the patent's abstract explains it: "The watermark identifies the content producer, providing a signature that is embedded in the audio signal and cannot be removed. The watermark is designed to survive all typical kinds of processing and malicious attacks."

The stuff is probably the most thorough and complicated technology ever to be applied to 99-cent music files. It's robust enough to resist all attempts to remove the watermark from the clip, including changes in time and frequency scales, pitch shifting, and cut/paste editing.