post commands, safe to delete?

[varekai]

I have a DVD with a menu, after playing the movie title it returns (loop) back to the menu.
I would like the DVD to stop (no loop) when the movie title has finished playing.
Is it safe to delete all post commands for the movie title using PGCEdit?
Or would that "break" anything?

[Video Dude]

If you really want to stop the DVD after the movie, put "Exit" as the first post command. Don't delete the post commands in case you ever want to restore it back to the way it was. Just "Add before" the new Exit command to the top of the post commands.

[varekai]

@Video Dude

OK, I'll try that. So deleting any post commands won't really damage the playback of my dvd?
But adding "Exit" would make things easier if I would like to restore my project?

Thanks for your help, I really appreciate it! :D

regards

[varekai]

@Video Dude

I have done some testing and found that using "exit", "nop" and
that an empty post command also prevents the DVD from looping.

Found these topics on DVD-Replica, does this mean that an empty post command
is within the DVD specifications?

http://www.dvd-replica.com/DVD/nop.php

http://www.dvd-replica.com/DVD/exit.php

http://www.dvd-replica.com/DVD/pgc.php

Quote:
"It is legal to have an empty PGC (having no cells and no command section) which does nothing.
A PGC can be defined in this manner to direct and control the playback of video and audio data."

regards

[r0lZ]

NOP doesn't affect the possibility to loop. As explained at DVD Replica, that command does nothing, and therefore is certainly not used to prohibit the loops. However, if the last post-command that is executed is a NOP, the playback ends.

If there is no post-commands in a PGC (or only post-commands that do not jump elsewhere, such as NOPs), then the playback should end, as when the PGC has finished playing, the player doesn't know what to play next. However, some bad players may continue with the next title. So, I recommend to add an Exit command anyway, to be sure that all players will exit.

Of course, if an Exit command is executed, a loop cannot occur, as the DVD stops completely. (You can think at the Exit command as a jump to the Stop state.)

Note that a cell command may also be used to jump to another PGC, or to exit. If that cell command is executed, the jump occurs immediately, and the post-commands are completely skipped, but the playback continues anyway (unless it's an Exit).

Of course, a dummy PGC (without video content) does not need post commands, as usually the playback is redirected to another PGC by the pre-commands. (It is however perfectly legal to have pre and post-commands in a dummy: if there is no pre-command to jump elsewhere, the post-commands will be executed normally after the last pre-command or after a Break pre-command.)

[varekai]

@r0lZ

Thanks for helping me! :)

I have lots to learn, I can see that...
Here's an image:
http://img524.yfrog.com/img524/1049/addexitpostcommand.png
I added the post command "1 Exit"
If I delete all post commands is that out of DVD spec?
It seems to work the same way, no looping.

regards

[r0lZ]

As explained in my previous post, no post commands should have the same effect than your Exit, but some players may continue automatically with the next title, so it is better to leave the Exit there.

The post-commands 2, 3 and 4 are useless, unless you want to leave them to remember how the original authoring was made.

[varekai]

@r0lz

OK, I will use post command "1 Exit" from now on when making non looping DVD's.

Thanks for your help, I really appreciate it! :D

PS/ A small donation is on it's way...