Why is removing .VOBs messing up menus?

[ddlooping]

Hi all.

Could someone explain in layman terms why removing .VOBs messes up menus (when played in a set-top)?

I rip a DVD.
Delete the .VOBs, .IFOs and .BUPs related to some unwanted extras.
I do not rename the remaining .VOBs, .IFOs, .BUPs.
If I play the result in WinDVD (using "DVD from folder), the menu works as expected.
If I then burn to DVD-R, the menu still works as expected in WinDVD, but not in my set-top player (Pioneer DV626D), whether I use IfoEdit "Get VTS" or not (not even sure why I'd need to do that but thought I'd give it a try ).
Some of the buttons behave normally, others like they have been re-assigned to other titles.

The movie: "The 6th Day", R1, NTSC.
- Play Movie (1)
- Audio Set-up (2)
- Subtitles (3)
- Scene Selections (4)
- Special Features (5)
---- Isolated music score (5a)
---- Link to two short extras (5b)
-------- Extra 1 (5b1)
-------- Extra 2 (5b2)
---- Talent files (5c)
---- Theatrical trailers (5d)
-------- First trailer (5d1)
-------- Second trailer (5d2)
-------- Fourth trailer (5d3)
-------- Fifth trailers (5d4)

After having only removed the "Theatrical Trailers" files:
- "5b1" jumps to a cell at the begining of the movie (Parental guidance), and loops it undefinately (I have to press "Stop" twice to also cancel the resume function), instead of playing Extra 1.
- "5b2" stops the movie.
- "5d1" plays Extra 1.
- "5d2", "5d3", "5d4" stop the movie (as expected).

I have also tried removing the .VOBs with MenuEdit (they are then replaced by 0kb ones) with the same result.

I'm not looking for the right way to do it (there must be plenty of guides around), just for a simple explanation as to why the unedited menus behave like if they had been edited.

Thanks in advance.

[FOO]

I believe that is because data is referenced by absolute
sector offsets in DVD navigation. If you move the pieces
around, a lot af addresses will be wrong. Get VTS sectors
in IfoEdit fixed that IF you just shrank the VOB sizes, but
kept all the pieces.

The DVD player programs reference files by their NAME in the
ISO filesystem. Settop Players do not use the filesystem and use
absolute sector addresses. So you can move things around, and
still play in the computer, but not in the Settop player.

[ddlooping]

Thanks for the reply, FOO.

So in theory, if I use MenuEdit to delete the .VOBs (which actually doesn't remove them but replace them with 0kb ones) and then IfoEdit to correct the sectors, the menu should work in my set-top, right?

I used "Get VTS" when I had entirely removed the files.
I'm in the process of burning another trial where I used MenuEdit and then IfoEdit.
Fingers crossed.

[Vejita-sama]

You have to remember/understand that DVD Videos use a file structure not a file format. So you can't just go around editing VOB files (add/delete) and expect the menu and file structure to 'adapt.'

The best thing to do is to strip the the unwanted VOB IDs (IFOEdit, DVD Toolbox, etc). Or you can replace them as suggested above (multiple ways to do this too).

[ddlooping]

It works!!

Now I'm going to use MenuEdit to remove the Theatrical Trailers buttons that are no longer needed (that now points to Extra 1).

One more question, FOO. Would this method work for most set-top players?

Thanks.

[ddlooping]

Thanks for your reply, Vejita-sama.

"...So you can't just go around editing VOB files (add/delete) and expect the menu and file structure to 'adapt.'"

I actually thought (and hoped) neither the menu nor file structure would adapt.
Pushing the button that used to play a particular .VOB would still play that .VOB if it still existed, stop the player or do nothing if the .VOB had been removed.
Just like clicking a link on a web page:
if the name of the anchor is correct and the file exists, you get to the corresponding page; deleting other pages doesn't re-assign the working links.
If the page doesn't exists or has been deleted, you get an error message.

FOO has now made it clear that's not the way it works.

[ddlooping]

P.S: what is the best method to use with MenuEdit, to remove a button functionality.

- Remove from menu?
- Hide and update commands as follow:
- Keep old?
- Replace with NOP?
- Jump to non deleted button?

Thanks in advance.

[FOO]

All my screwing around in the IFOs came to a screeching halt
when DVD Shrink came out. I don't like menus
I do put 'em on homemade stuff, but that's a new creation and just works.

I suggest NOP for dead buttons, what if you stepped on the brake on your
car and the windshield wipers came on ?

edit: actually remove from menu would be better. I didn't know it did that

[sumibas]

If you just leave the _0.vob files and delete all the susequent vob files You will not have problmes this worked for me.

[ddlooping]

FOO, I don't normally bother with the menus either.
Being the moderator at the official DVD Shrink forums, I'm only trying to provide a way to remove extras while keeping functionning menus.
It's one of the most requested features, and I don't know if and when it will be implemented.

I've already made a simple "calculator" as part of a guide to use DVD Shrink, MenuEdit abd IfoEdit.

http://www.dvdshrink.info/calculator.php

But before I can submit this easy workaround I want to make sure it works.

[ddlooping]

Thanks for the tip, sumibas.

I guess you would also have to keep the corresponding .IFOs and .SUBs, right?

Do you have tested the backups you made this way in several set-tops?

[FOO]

The _0,VOBs are sub menus. What if you go to one of them
and hit a button ? - lost in space ?

[ddlooping]

Is that how you ended up on Uranus?

I think I'm gonna try and get a few members of the DVD Shrink official forums to do some testing using both these methods.

[FOO]

Whatever happened to the "delete playback" button on IfoEdit
That probably does the same as NOP on MenuEdit.

I may be wrong but I thought IfoEdit would repair an existing
menu. A possible plan would be NOP the button, remove the associated
VOB and have Ifoedit fix the menu sector offset table.

Next time I get bored I'll try it.

[ddlooping]

"Next time I get bored I'll try it."

Please let me know the result.

[DoubleShadowIce]

P.S: what is the best method to use with MenuEdit, to remove a button functionality.

- Remove from menu?
- Hide and update commands as follow:
- Keep old?
- Replace with NOP?
- Jump to non deleted button?

Thanks in advance.

Jump to non deleted button. Even MenuEdit's author, Dimad, suggests it. But it is only on the registered version. It's only about $16 for registeration but it'll be one of your best editing software you'll have.

[ddlooping]

Thanks for the reply, DoubleShadowIce.

That's what I chose after having noticed it was the recommended option (I had missed the tooltips).
I'm already a registered user.