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Mechcozmo
Jul 19, 2006, 12:59 AM
This question doesn't really fit anywhere else... so here goes.

Some disks are copy-protected. However, I want to use them as disk images on my computer. (On my Windows box, but the same could be applied to the Mac) Why do disk images tend to fail? Why don't they just read the raw data on the disk and turn that into an image, seeing as the program can read the disk and work based on it.
Can't the computer take everything about a CD and replicate it into an image?



slooksterPSV
Jul 19, 2006, 11:23 PM
This question doesn't really fit anywhere else... so here goes.

Some disks are copy-protected. However, I want to use them as disk images on my computer. (On my Windows box, but the same could be applied to the Mac) Why do disk images tend to fail? Why don't they just read the raw data on the disk and turn that into an image, seeing as the program can read the disk and work based on it.
Can't the computer take everything about a CD and replicate it into an image?
Well, there are programs that can read the RAW data, but it'll still fail if its copy-protected.


Copy protection in recent digital media
The MPAA's "Copy Protection Awareness Icon" for DVDs.
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The MPAA's "Copy Protection Awareness Icon" for DVDs.

More recently, publishers of music and movies in digital form have turned to encryption to make copying more difficult. CSS, which is used on DVDs, is a famous example of this. It is a form of copy protection that uses 40-bit encryption. Copies will not be playable since they will be missing the key, which is not writable on DVD-R or DVD-RW discs. With this technique, the work is encrypted using a key only included in the firmware of "authorized" players, which allow only "legitimate" uses of the work (usually restricted forms of playback, but no conversion or modification). The controversial Digital Millennium Copyright Act provides a legal protection for this in the US, that would make it illegal to distribute "unauthorized" players—which was supposed to eliminate the possibility of building a DVD copier. However, CSS and other such software-based solutions have been reverse engineered (see DeCSS), providing access to the encryption keys and methods.


There's what you need to know.