libdvdnav is a library that allows easy use of sophisticated DVD
navigation features such as DVD menus, multiangle playback and even
interactive DVD games.

All this functionality is provided through a simple API which provides
the DVD playback as a single logical stream of blocks, intermitted by
special dvdnav events to report certain conditions. The main usage of
libdvdnav is a loop regularly calling a function to get the next
block, surrounded by additional calls to tell the library of user
interaction.

The whole DVD virtual machine and internal playback states are
completely encapsulated.