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New Copy Protection to Make Playing DVDs on a PC Difficult
The Cowardly Pirate writes "ZDNet's Hardware 2.0 blog is reporting that new copy-protection software for DVD publishers from a company called ProtectDisc not only makes it difficult to rip movies that you've purchased but also prevents discs from playing in a Windows PC at all. From the article: 'Protect DVD-Video is the brainchild of a company called ProtectDisc. Part of the copy-protection mechanism is a non-standard UDF (Universal Disc Format) file system which results in the IFO file on the DVD (this is the file responsible for storing information on chapters, subtitles and audio tracks) appearing to the PC as being zero bytes long.'"
She isn't going to know about that tool, or how to use it, and I'm about as sick and tired as I can be of setting up the workarounds for restrictions that shouldn't even exist.
Eventually only the hackers will be able to watch movies and play games on their computer.
Then, when the next blockbuster movie sell a grand total of four DVDs, maybe the movie and television studios will finally realize how much money this is costing them.
More likely they'll blame piracy.
"...new DVD protection that makes it impossible to play it at all"
Nah, the protection won't kick in until the main feature. You'll always be abe to see the trailers and commercials, no doubt.
This is mainly a little DVD-Video tidbit to explain how technically this works.
For the DVD-Video spec, the actual file system being used is irrelevant and is mainly used to "boot" the disc and discover where the very first data sector is located at on the DVD disc. From then on, at least in theory, all of the navigation to the rest of the DVD media is handled internally within the DVD-Video files themselves, including the MPEG data, as the navigation within the video data is handled with the use of special navigation packets.
So for a set-top box on your home television, the data scanners ignore the UTF file format and just march through the data according to the DVD-Video specs, not even aware that there might be a problem. Besides, these set-top boxes have just enough of a file system BIOS just to get to the "root" sector and not much more. Sometimes the "higher-end" ones will try to scan for MP3s or other kinds of media files, but that is a bonus and not required for playing the video data itself.
As for PCs, the operating systems are obviously designed to trust in the file system to believe that what the file system is telling you is also correct. Obviously you can mess with the order of the files and make something playable only on PCs and not set-top boxes, but usually you are more worried about the set-top ones rather than some hobbiest with some DVD playback software. The PC-based DVD-Video playback software is usually designed to trust in the file system and does the file requests through normal OS-related file requests rather than doing low-level sector navigation. This is a sign of good programming, not the lack thereof.
What is being done here is a very cheap hack that took the brains of a half-competent software engineering intern who knows just enough about the specs to get him/herself into some serious trouble and doesn't know the basics of trying to stick with known standards. Or to understand the need for redundant systems to try and protect data through multiple means of accessing the information. As has been pointed out, by doing this the file system is essentially corrupted, so normal OS file system requests will not be able to retrieve the data, unless you are accessing information on the DVD drive via individual sector requests instead (that would be the "hack" to break this "encryption" system). BTW, the "file size" of the IFO files is also recorded in the IFO file format itself as well, so "recreating" the IFO files is trivial in this situation if you can access the individual sectors.
I certainly hope that this idiot who designed this system didn't get a patent on the subject. I will go down right now as somebody to contact if you want to break the patent to testify that this is not a patentable idea in the first place. And as has been pointed out by others, this is clearly in violation of the DVD-Video standards and as such you can't claim compatability to DVD-Video by using this system. This is not a copy protection scheme but rather a corruption of the file system, as has been pointed out, and taking on a percieved weakness in the organization of the DVD-Video format.