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Cinavia protection is an audio watermark that is present in addition to AACS protection and helps prevent theatre recordings of movies (CAM recording) to be released online or as a personal copy. CinaviaĬinavia is a protection tool developed by a company called Verance and since 2012 it is compulsorily supported by all Blu-ray players.
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Since then there is a continuous stream of changes in upcoming VMs along with BD+ discs which are yet again reverse engineered by hackers keeping the loop running. However, BD+ protection was hacked by reverse-engineering the VM in 2008 by hackers who were looking at how to decrypt Blu-ray with BD+ protection. The virtual machine runs the BD+ instructions and fetches a “Fix-up Table” to fix the mangled parts of the video. The instructions are known as BD+ instructions and run on a virtual machine. This protection garble or mangles the video content with instructions within the disc itself on how to repair the content. BD+ ProtectionīD+ Protection is optional protection that is applied in addition to AACS encryption. This system ensures that even if there is a hack and a list of keys are leaked (which happens quite often) by people looking to decrypt Blu-ray discs, the AACS consortium still has the chance of revoking the old list and creating a new one. Whenever a newer version of Blu-ray is inserted into a player, the drive checks for the Host Revocation List in the “Media Key Block” and updates it in the permanent non-volatile memory of the device. The list of keys with AACS encryption that are available with the players can be revoked in case there is a suspicion that the keys have been compromised. Using these two a Media key is generated which decrypts the Title key which is finally used to decrypt the audio and video in the disc. The Blu-ray players or the device have the Device key while the disks have Media Key Block. The encryption used as part of this is 128-bit AES encryption. It stands for Advanced Access Content System (AACS) and the consortium is known as AACS Licensing Administrator. This encryption has been developed by a consortium of media industry leaders - Disney, Intel, Microsoft, Panasonic, Warner Bros., IBM, Toshiba, and Sony. Such protection is applied for pre-recorded disks and the same goes for other Blu-ray protections. The only files on which this protection is applied are the stream files and not the other files that are present in Blu-ray disks. This is a standard that the prerecorded Blu-ray comes with.
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No matter which kinds of copy protection, they can be applied to both Blu-rays and DVDs. Besides them, others may be also used but are less popular than them. There are five kinds of Blu-ray copy protections in detail.
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