DVD-Audio has been around for almost 10 years know. The format delivers high-fidelity audio content. It is not intended to deliver video, and is not the same format as DVD’s that carry movies. (Follow the above link to read more)
This post gives a quick overview of the type of copy protections schemes that are used. The idea behind this is copy protection. Aims to prevent users from extracting audio (copying).
1. Content Protection for Prerecorded Media (
CPPM).
CPPM uses a media key block (MKB) to authenticate DVD-Audio players. In order to decrypt the audio the players must obtain a media key from the MKB. The player must use its unique key to decrypt the MKB. Important to note that C.C.P.M. encryption has been broken since 2005.
The watermark is typically embedded into the audio once every thirty seconds, this watermarking cannot be removed. If a DVD-Audio player encounters a watermark on a disc without a valid MKB, it will halt playback. Also if the DVD-A player detects that the watermark does not match the DVD-A disc (eg you've made a “backup” of your DVD-A), the playback will cease.
Although note that many DVD-A players have no watermark detection, while others can be ‘patched’. Apparently You can play ripped and watermarked DVD-Audio on your computer using CyberLink PowerDVD (amongst others), but I have not tested this.
