DRM Watermarking It’s nice to see DRM come stumbling down, but that doesn’t exactly mean it’s the end of file protection as we know it. Microsoft had patent 7,266,697 approved last week that would essentially replace DRM on music files with a watermark.




The patent was filed back in 2004 by Darko Kirovski and Henrique Malvar, who both work at Microsoft Research. The watermark technology doesn’t encrypt files like a typical DRM does nor does it prevent the unauthorized use and distribution of files. What it’s actually used for is to identify the owner, and if a file is illegally distributed that information would serve as a digital fingerprint that points back to the original purchaser.

Like all software there has got to be a way for this to be hacked, but the patent does describe what Microsoft believes to be a nearly foolproof solution:

Unlike printed watermarks, which are intended to be somewhat visible, digital watermarks are designed to be completely invisible, or in the case of audio clips, inaudible. Moreover, the actual bits representing the watermark must be scattered throughout the file in such a way that they cannot be identified and manipulated. And finally, the digital watermark must be robust enough so that it can withstand normal changes to the file, such as reductions from lossy compression algorithms.

Apple has already started doing something similar where they embed the owner information into DRM-free songs purchased on iTunes. Apple didn’t, however, go to such extravagant lengths to embed the data in the song, and software such as JHymn is supposed to be able to remove it.

Source: Information Week