Parental Management Levels (Windows Embedded CE 6.0)
1/6/2010
All or part of a DVD disc can be encoded with a parental management level (PML) numbered from one to eight. Eight is the most restrictive level (adults only) and one is the least restrictive (all ages).
This system is intended to prevent children from watching adult content without parental consent while allowing adults to watch child-safe content. In the United States and Canada, some of the levels map to the rating system of the MPAA (G, PG, PG-13, NC-17), but this is not the case in other areas of the world.
Because program chains (PGC) can exist logically within a parental block, there may be two versions of the same program chain in a title, each assigned a different PML and in a different parental block.
For example, a child who logs in and plays the disc would see one version of the program chain and an adult who logs in would see a different version, assuming that the application supports PMLs.
A DVD-Video content author can add commands to a program that temporarily modify the PML for the current title. When the player executes these commands during playback, it can compare the existing PML to the temporary PML and take an appropriate action.
This action can include continuing to play, allowing the user to increase their level, or halting playback altogether. Authors typically place presentation data for temporary PMLs in angle blocks.
It is the responsibility of the player application to enforce the parental levels.