4.7. PGC in a VTS
Following are excerpts from the Unofficial
DVD specifications Guide 2.2
...PGCs (program chains) in a video title set
(VTS) must conform to the defined
parameters set for the VTS, such as the video format (NTSC or PAL), the type
of encoding used (MPEG-2 for video, AC-3 for audio), encoded bit rate, etc.
PGCs contain the required playback and navigation information to play
video objects and audio streams in a particular order designed by the DVD author.
A video title in a VTS may contain one or more PGCs. These PGCs are numbered so that
the DVD player knows that they belong to the same video title. The video title set
keeps track of the order and physical locations of the PGCs within a VTS title.
This makes VTS-domain instructions simple and efficient to access a relative PGC
within a VTS title...
4.8. Graphical display of PGCs in a VTS
Details on the following illustration regarding possible virtual commands in the title
) are explained in the
Unofficial DVD specifications Guide 2.2