Navigation error

[Rainshaker]

Someone authored a DVD for me although they messed it up a little as I've had to run it through IFOedit to correct a few navigation pointers, although I've managed to correct the re-allocation errors I was getting when trying to burn using from Imgtool the DVD refuses to load the main menu but instead stops prior to loading it.

When playing the DVD the normal trailers play but when the DVD is suppose to then load the main menu it instead stops, as a result I have to press play again although it goes straight to the beginning of the movie, although the menu is there I cannot access unless I press the remotes DVD menu button whilst the actual movie is already running.


Does anyone know how I can correct this navigation error?

Regard Rainshaker

[Dimmer]

You have to locate two things:
1. The last PGC that plays before player stops after the trailers
2. Location of the main menu. On a simple DVD, it's most likely a root menu of VTS 1.

Then add as a last command of the Post commands of the PGC you found in step #1 jump to the main menu. Perhaps, it would look something like this in IfoEdit:
(JumpSS VTSM) Jump to TitleSet(vts): 1, Title(ttn): 1, root-menu
Depending on how the trailers are stored, use JumpSS to jump from another menu PGC, or CallSS to jump from a title domain PGC.

[Rainshaker]

Hi Dimmer,

Thanks for the reply, I've tried what you said although without success, until now I have'nt had to really use IFOedit to manually manipulate/repair a DVD's structure, although I've been unsuccessful so far I have to admit the more I'm beginning to understand a DVD's structure the more interesting I'm finding it.

As Fas as I can tell the error seems to stem from the end of the trailer as suspected, the PGC in question is PGC_1 I see at the end of the post command there is a cell command I was wondering what this does, I've posted the IFO so I was hoping if you could see what the problem is

Regards Rainshaker


IFODownload (http://a1backup.users.btopenworld.com/VTS_07_0.IFO)

[Dimmer]

There doesn't seem to be anything wrong with that IFO file. After playing PGC_1, it jumps to VMG, which is pretty much equivalent to what I suggested earlier. Apparently, the problem lies in some other IFO with first suspect being VIDEO_TS.IFO, and another one is the IFO corresponding to the VTS containing the main movie. Probably the latter is VTS_01_0.IFO since the movie starts playing when you press the Play button. DVD players usually stop playback when they come across an illegal command, so that could be the reason. There is also special EXIT command that does this purposely, but normally it's never used.

Cell command is executed after the cell is played. That particular command LinkTailPGC jumps directly to the Post commands skipping the rest of the cells in the PGC.

Sometimes during troubleshooting it's useful to change cell still time from zero to 5-10 seconds one by one for short suspisious cells around the failure point. This way, you can check which cells were actually played without messing up DVD structure. Of course, you can't do this for dummy PGCs, i.e. those without video.

[Rainshaker]

I'm not one wanting to be spoon fed anything so before replying I had a good look at both files you suggested although I have to admit I have'nt been able to see any obvious error,

I'm a little confused now as I have to correct the IFO's or imgburn gives me the re-allocation error, this is fine and PowerDVD continues to play the DVD files from the HD although when I get the VTS sectors neither PowerDVD nor my standalone goes to the menu, the standalone has never gone to the menu although PowerDVD did until I got the VTS, sectors, this confuses me now as I've always understood you have to get VTS in order to get playback on a standalone,

Help :confused:


VIDEO_TS.IFO (http://a1backup.users.btopenworld.com/VIDEO_TS.IFO)

VTS_01_0.IFO (http://a1backup.users.btopenworld.com/VTS_01_0.IFO)

[Dimmer]

Okay, you'll have to publish all 14 of your IFO files since the VMG contains jumps to a lot of different titlesets. Apparently, audio menu of VTS 2 serves as a hub of all navigation while the VTS itself contains only one short blank clip (title #3).

Now, here's the important question: did you delete any of the IFO/BUP/VOB files by any chance? Just in case you think that you can simply delete unnecessary or blank titles by removing VOB files, well, you can't, so you'll have to restore them. I'm mentioning this because correcting VTS sectors messes up the DVD while normally it's a harmless operation, and it actually does something only if the physical size or location of the files/titles has changed.

Also, to the best of your abilities, try to describe what titles and menu PGCs are played before the failure.

Out of curiosity, what studio released the disc? Many studios use the same template on each disc, making it easy for them to author and hard for us to disassemble. I don't remember seeing this particular one.

[Rainshaker]

I personally never deleted any of the DVD files, one thing I did notice is the original re-authorer has blanked 2 titles 9+11 using a vob containing 3 cells ripped from the THX optimzer VTS, I originally corrected this by replacing the titles with a single cell blanked vob and updated the IFO's although this never fixed the navigation error it repaired the re-allocation error which I also had with main movies title set, even though these titles are'nt called up there are also illegal navigation errors in some buttons in the menu so at a guess I'd have to say the re-authorer was'nt that clever, so it some how the re-authorer has messed up the DVD navigation structor some how.

I found is when the DVD is played through PowerDVD it plays through the trailers as goes to the menu as normal although when played through IFOedit it goes through the trailers then straight into the mains movies title.

Titles 4,5,10 play before the error and although IFOedit claims to have played title 1 I havent been able to visually see it called up in the status bar,


The error occurs after playing title 10 chapter 6 (VTS_07_01) this would of course be PGC_1 PG6 I say PG6 although because it is such a small cell it plays so quickly it does'nt show up in IFOedits DVD players status bar, 00.00.00.15 playing time tells me it must be navigation information, this size cell seems to appear in many of the VTS's PGC's


The DVD itself is a D*sney, I'm not keen on having to re-author D*sney DVD's as there is awlays so much content to deal with, the only positive note I've found with D*sney DVD's is after stripping away all the extras you usually get the main title with minimal/no compression.


The IFO's attached are in the original state I recieved them in although initially re-authored.

IFO (http://a1backup.users.btopenworld.com/IFO.rar)


Regards Rainshaker

[Dimmer]

Well, I looked at the IFO files and still can't see anything wrong with them. Indeed, it should play the titles 4, 5, 10. Then it supposed to go like this: VTS 7 Root menu (PGC 1) - VMG PGC 8 - title 2 (VTS 1 PGC 2 - half-second blank clip) - VTS 1 Subpicture menu (PGC 2) - VTS 1 menu PGC 17. This menu PGC 17 I expect is the main motion menu. You can confirm that by checking VobID 3 and 4 in VTS_01_0.VOB. VobID 3 contains the menu with intro played once, and VobID 4 is the menu only looping indefinitely.

Since the DVD fails after title 10, you can do some troubleshooting by increasing cell still time for the short cells it jumps through after that point. If you set the still time to a different value for each cell, you can figure out in PowerDVD, which cell has just been played. For example, set still time to 5 seconds for the cells 7 and 8 in PGC 1, VTS 7. You'll notice 5 sec. pause after title 10 has been played. Then set cell still time to 10 sec. at the end of title 2, i.e. cell 1, PGC 2, VTS 1. PowerDVD will restart the timer at that point and pause for 10 more sec. if everything is going right. There is a couple more cells you can check this way among those I mentioned above, but you'll have to turn Pre commands into Post commands first. Specifically, VTS 7 Root menu and VTS 1 Subpicture menu contain short clips, which are normally bypassed. To change that, set the number of Post command equal to the number of Pre commands for these PGCs; set the number of Pre commands to 0; set cell still time to some value you didn't use before so you can see whether the player actually goes to these PGCs. I hope you understand my suggestion since it allows you to narrow down the failure point, because there is a lot of stuff going on almost instantly between title 10 and the main menu.

As for the allocation errors, there is one proven method: perform a mock strip in IfoEdit. Of course, if you don't know for sure, which file is causing problems, I suppose you'll have to do it for every IFO file, which will take a while. You may start with menu files. In IfoEdit, click Menu Extras, select Strip VobIDs, Correct Vob-Unit pointers, Correct original IFO files; leave VOB Expert options as is; clear Auto Copy Menu files; select output folder. When you click OK, it'll show you the list of VobIDs, click Check All and then Strip. It will recreate IFO and VOB files correcting everything that could be corrected. Copy the output over the original files (back up the originals if you have enough space). If you still get allocation errors, repeat the procedure using VOB Extras button for all IFOs except VIDEO_TS.IFO. Get VTS Sectors when done. If you get allocation errors at this point, then probably you should re-rip the original since apparently you won't be able to burn this DVD properly anyway.

[Rainshaker]

Thank you for taking the time out and helping me with my navigation error it is much appreciated, I'm not gonna give up yet and I'll try everything you've suggested,

If anyone ever gets re-allocation errors they can run the IFO's through DVD shrink, anything other than a good IFO will instantly give you a error :D


Regards Rainshaker