9. PGC Architecture
Each title may have up to 999 program chains (PGCs). A PGC may have from 0 to 255
programs, which are ordered collections of pointers to cells. Physical data and
the logical presentation data structure converge at the cell level. The PGC connects
cells together, defines the order of programs, and which cells are played. Programs
within a PGC are used for sequential, random, or shuffle play, and cells can be used
by more than one program chain. Programs may contain one or more contiguous cells which
can act as a chapter of a video title. These program units are also known as part-of-titles
due to the fact that they may be stored in different PGCs.
Groupings include parental management blocks, angle
blocks for multiple camera angles, interleaved blocks for seamless branching, etc.
A PGC contains pointers to the next, previous, or GoUp PGC to support common remote
control buttons Next, Previous, and Return, respectively. A PGC provides a 16-color
palette for subpicture colors which may be present in any of the cells in the PGC.
A PGC has a command table that can have up to 128 pre-commands, post-commands, or
In summary, a PGC provides the following major functions in all domains:
|Program Chain (PGC) functions|
|Number of programs and cells|
|Audio stream status|
|Subpicture stream status|
|Next PGC number|
|Previous PGC number|
|GoUp PGC number|
|Still time in seconds|
|Program playback mode|
|Palette for color index 0-15 (0, Y, Cr, Cb)|
|Command table for pre, post, and cell|
|Program map for chapters|
|Cell playback information|
|Cell position information|
The Unofficial DVD specifications
is now available in Adobe
Acrobat PDF ebook format. If you do not have a permanent Internet connection, this ebook
can save you a lot of connection time by reading it off-line and it contains more information
than presented on the web pages. Each DVD instruction is organized as a bookmark so you can
get to the desired page of any of the 36 DVD commands with just a click. A DVD command
generator is provided so you can generate 100%-compliant DVD commands from your desktop.
All the research have been done for you and summarized in an easy-to-read format.
This is the only ebook of its kind so save yourself a lot of time and efforts searching.
You cannot get similar high-quality information anywhere else at this price.
Please click here to get to the order page
of the Unofficial
DVD specifications 2.2 ebook and thank you for visiting.
The ebook version offers these immediate benefits:
Having more detailed information than on the web pages.
Understanding DVD terminology and architecture.
Better use of authoring products such as
Sonic Scenarist, Adobe Encore, DVD-Lab, IFOEdit, etc.
Detailed knowledge of DVD virtual commands.
DVD VM Command Generator 2.75
with the same engine as
seen on this site to generate 100%-compliant DVD commands.
Understand how DVD menus work with navigation commands.
Conversion of DVD color from YCrCb to RGB
plus a free copy of DVD-Color 2.16
30-day email technical support.
Acquire the technical background to write DVD applications
and a lot more...