Penguin
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This page describes the evil parts of the DVDVideo specification.

Region Coding

Region coding is a way for distributors of DVD-Video discs to restrict which parts of the world those discs can be used. The world is divided into 6 regions, and all DVD players sold into those regions are supposed to have the corresponding region number built-in. When a DVD disc is inserted into a player, the player is supposed to refuse to play the disc unless its code matches that of the player, or the disc has region code 0 (compatible with all regions).

Macrovision

Macrovision is a technique for committing unholy fiddles on an analog video signal in a way that doesn't affect TVs trying to show the picture, but does confuse video recorders trying to make a copy of it.

The circuitry for committing acts of Macrovision is built into all DVD players. It can be enabled by setting a bit in the .VOB file. However, before setting this bit, you have to pay a licence fee to Macrovision Corp.

Encryption

Store-bought DVDs are commonly encrypted with CSS as a CopyControl measure. The encryption keys are stored in a special part of the disc that can only be accessed via a special handshake between the software and the drive, knowledge of which is only disclosed to those who sign an NDA with the DVD Copy-Control Association. Mass-market DVD writers cannot create discs containing this special key area.