Macrovision, the DRM firm perhaps best known recently for creating security holes in Windows with its SafeDisc DRM, has purchased the intellectual property surrounding the BD+ DRM scheme used by Blu-ray to thwart attempts at copying. For $45 million, Macrovision will get ownership of the Self-Protecting Digital Content (SPDC) technology that forms the basis for BD+ as well as associated patents owned by Cryptography Research.
Both Blu-ray and HD DVD use AACS to thwart copying, but that was cracked last spring. Blu-ray is alone in using an additional layer of security, BD+, to keep users from copying Blu-ray discs. BD+ works via a small virtual machine that is launched each time a disc is inserted. The VM does some code transformation to correct deliberately-corrupted video streams, and checks to see if the disc is playing on a Blu-ray player known to have been hacked. If the player has been compromised in the past, playback can be disabled. When the disc is ejected, the VM disappears from memory, which, in theory, makes it more difficult to hack or reverse engineer.
One small problem: BD+ was hacked earlier this month by SlySoft, makers of AnyDVD. The crack made good the company's boast that a crack would be available by year end and called into serious question the claims made by Blu-ray's backers that BD+ was uncrackable.