miniDVD: different "behavior" in stand-alone vs. PowerDVD & mounted disc-image

[CirTap]

Hi folks,

first, I have no idea if this belongs in this category: I found none to be appropriate, and as PcgEdit is involved ...

I was wondering if anyone can explain why the menus on a miniDVD I authored played fine in PowerDVD running a Nero-Image mounted in DeamonTools but failed totally and locked my stand-alone -- which happens to play miniDVDs just fine.
It's just some 550MB so I burned them with Nero 5.5 on a CD-R in ISO data-mode into an .nrg image file, following some guide I found on the net.
I always test the menus for (regular) DVDs from a disc image created with Nero 5.5, and if all's fine, burn that .nrg file to DVD. I found discs, no matter what brand or type, often had CRC-errors if I let Nero burn the VIDEO_TS folder directly -- but that's another story ...

To make the following long story short: using PcgEdit I made an ISO disc-image setting the "CD-R 700MB" sectors. Then burned that .iso file with Nero. This disc plays like a charme !?
Is this how it must be done for miniDVDs? or was it just a coincidence that Nero (maybe) messed up these particular set of DVD files while it created the .nrg file or burned the disc?

This has been my first miniDVD, but I plan to put extras and other specials I find for a movie onto miniDVDs if space permits, instead of "wasting" half a DVD for a few "nice to have clips" or even degrade the quality of the main movie or TV episodes. And yes, I'd rather put them on miniDVD with nice menus instead of SVCD to satisfy the artist in me ;-) (besides I don't want to learn about S/VCD features or inabilities)

Now, here's how this disc is made up:
it contains a bunch of ripped extras and some downloaded, mocked-up "web-specials" (interviews and stuff).
There's a VMG menu (first run) followed by a VTS "main menu" to select chapters from two titles: first DVD-full (extras) and second DVD-half (web-specials).
The stand-alone just deadlocked after the VMG timed-out in order to jump to the VTS menu, and the menu-buttons did nothing but display an unimpressive black screen, but I could still "goto" the individual titles and chapters via remote. So that "part" of the data seemed to be ok.
However, PowerDVD (using the .nrg source mounted in Deamon) performed as expected, and nicely jumped from VMG to the VTS "root menu", or from VTS chapters back to the menu, according to the time-outs, LinkTails etc. and also the buttons worked as intended.

Now from my poor knowledge of DVD structure I thought it could be related to wrong "sectors" - or whatever - in the IFOs, either because
- the authoring tool placed them as if the files would go on a DVD
(something it could undoubtly presume)
- Nero messing up the files (32k gap?)
- a bad, corrupted disc
I noticed that Nero "reordered DVD files", although I burned a CD-R, so it seemed to examine the files and found them to be DVD files, despite I setup burning a CD-R. Actually I though this would be a nice behaviour, but after this disc happened to be screwed up ...

So, can anyone enlighten me about what had possibly happend or what I made wrong?

CirTap

[r0lZ]

First, you need to know that there is no difference between a mini-DVD and a real DVD-R, beside the space available, of course. The files are layered on disc the same way, and the VTS sector pointers must be calculated the same way, too.

When you burn DVD-Video files (with or w/o additional DVD-ROM data files) with Nero, you must burn a DVD-Video or a mini-DVD-Video. Maybe Nero is smart enough to understand what you are trying to burn, and it will select the right mode for you, but I'm not sure.

PgcEdit fixes the VTS sector pointers when you save the DVD.
If the 32K gap option is ON when the files are saved, the pointers are calculated to force the burner (or the ISO image maker) to leave at least 32K of space between the IFO and BUP files. Nero ignores these pointers, and recalculate them. This means that it is unable to respect the 32K gaps. But its output should work anyway, unless there is a CRC read error on both the IFO and the BUP file.
Of course, if you burn an ISO created by PgcEdit and MkISOFS, Nero has no way to move the files, and so it should not modify the pointers, and it should respect the 32K gaps.
If you don't use the 32K gap option, the VTS sector pointers should be identical with PgcEdit and Nero.

The fact that the Nero image can be played with a software player is not a proof that the pointers are OK, since they are not used by the software players.
The strange thing is that you can play your titles, but not the menu. Maybe there is something wrong with the placement of the menu VOB in the image created by Nero?

In short, I don't know why the Nero image fails. But I am happy to see that PgcEdit works fine. :)
Anyway, there are numerous problems when burning a DVD-Video with Nero, especially with double layer discs. So, continue to use PgcEdit, to avoid bad surprises.
And why do you switch to Nero to burn the image? DVD Decrypter is largely superior to write without errors. It's my hint of the day. :D

Note that you don't need to specify the Mini-DVD option in PgcEdit's burn setup. It is only used to warn the user if the compilation don't fit on a CD-R.

[setarip_old]

@CirTap

Hi!

Instead of creating an .NRG or other form of image file, try using NERO in "Mini-DVD" mode (One of the choices under "CD", NOT "DVD") - Copy ALL related files (.IFOs, .BUPs, .VOBs) into the RED "VIDEO_TS" folder - and burn...

[zacoz]

@CirTap

From a satisfied PgcEdit user, I suggest creating your image and burning from PgcEdit (thru use of mkisofs & dvddecrypter) all the time - even when not needing to do any editing. You can be sure to avoid the 32K gap issue and have a more reliable burn.

[CirTap]

Hi,
thank you all for your great responses.

in reverse order ;)

@zacoz: for some reason I think dvddecr. (or PgcEdit?) displayed an "irritating" message about the image to be burned on disc - but I could be wrong :) I clicked way too many buttons that day, so I might be mixing up things <g> I just hit the burn-with dvddecr. button in PcgEdit testwise to see what happens, but then decided to burn the .iso file with Nero anyway.
But I'll certainly give it try next time. I don't mind using something else to burn the discs as long as it worx.

As a side note: I really love PgcEdit's trace mode as I'm playing with VM commands and "more interactive" menus for my own original footage.

@setarip_old: well, apparently there is no such entry available in Nero v5.5; I thought of using it, too, but as I coudn't locate one (there's only Video CD, SVCD, and some UDF/ISO variations), I decided to search for a guide on the net, and it said to burn in plain ISO data mode. Still, Nero discovered the files to be DVD related and reordered them - and probably tweaked them too much :)

@r0lZ: very interesting! that was actually the information I was seeking. I thought "sectors" depend on the media type/size/formatting, like a hard drive.
I did several "things" in PcgEdit, so I dunno which one actually forced the app to modify VTS1's (?) IFO and VOB when I saved the DVD.
Of course, if you burn an ISO created by PgcEdit and MkISOFS, Nero has no way to move the files, and so it should not modify the pointers, and it should respect the 32K gaps. that was my plan and hope, and I'm pretty confident, Nero left the .iso as is but messed up the files in its "own" .nrg. Dunno why the folks @ Ahead ignore this magic boundary even in v6 if it can be that cruicial? - maybe they're so confident Nero never "creates" CRC errors, even on shreddered discs? :-))
If you don't use the 32K gap option, the VTS sector pointers should be identical with PgcEdit and Nero. hmm, I dunno where to look at or what tool to use to find if there is any difference. IFO sturcture, "tables" and all these "magic numbers" I'm presented with in PgcEdit or IfoEdit are still very, very irritating. I just managed to get a tiny understanding of VM commands so far, but that's about it; still struggling with the (real) difference of "cells" and "chapters" ... guess I'll post another Q. on that topic anyway :)
Note that you don't need to specify the Mini-DVD option in PgcEdit's burn setup.thanks for that note; it looked like an "essential" setting to me, thinking of sectors like on a hard disk and such, so I turned on on "to be safe". Now as I look at the values, it's clear they're just the available sectors not their "size" or whatever -- didn't realize that in the first place.

Have fun,
CirTap

[r0lZ]

hmm, I dunno where to look at or what tool to use to find if there is any difference. IFO sturcture, "tables" and all these "magic numbers" I'm presented with in PgcEdit or IfoEdit are still very, very irritating.You can look at the VTS pointers with IfoEdit. In all IFO files, most of them are in the VMGM_MAT or VTSI_MAT table, at offset 0c and 1c, and between c0 and e4. A sector is 2048 bytes long, and the sector pointers are usually relative to the start of the titleset or the start of the IFO file.
In the VMG_TT_SRPT table are also the pointers to the beginning of the titleset for each title. These pointers are relatrive to the start of the VMG (ie the start of VIDEO_TS.IFO.)
The most important pointers that are modified when the 32K gap option is on are the Last Sector of VMG, at offset 0c in VMGM_MAT, and the Last Sector of VTSI, at the same position in the VTSI_MAT tables. Don't forget that these pointers are modified only when the space used by the VOB files of the titleset (or of the VMGM) are smaller that 32KB.
The same pointer at offset 0c in VMG_MAT is also modified to align properly the layer break cell with the beginning of an ECC block, when you burn double layer discs with PgcEdit. This is something Nero 6 seems to be unable to do correctly.

[CirTap]

wow! thanx. had to read this thrice to get it - sort of 8-) gotta copy this to my "dvd notes"; overwhelming this is ...
this stuff really is a science of its own kind, I guess I've never been confronted with such a complex thing like DVDs in my whole IT career :-) all this just to have some moving pictures with sound, lol
oh, and for the records: PgcEdit is some incredible piece of software, if I'd knew before what it's capable of! The name is probably the biggest understatement ever!! :-) which is why I totally ignored it for a long time (why on earth whould I have a need to "edit PGCs"??)
Chapeau! Hats up! I'll check my PayPal balance, r0lZ :-)

have fun,
CirTap

[r0lZ]

Thanks!

[setarip_old]

@CirTap

well, apparently there is no such entry available in Nero v5.5

That's quite true - and you are operating with an antiquated version of NERO. By all means upgrade to v.6.xxx

[CirTap]

@setarip_old: thanx for this advise, but I seriously don't think I will upgrade until I absolutely have to; having DL burner and player some day in the far future ... maybe.

v6 and later are so overloaded with "user friendly" stuff and wasteless apps, I have no need for -- it could have been a Microsoft product!
I don't need another shabby wave- or movie-encoder/editor or whatever this poor-man's multi-media-suite now gratefully offers. v5.5 already has more "features" than I really need or want, and that's burning data, not producing or editing it.
just because I had trouble with this miniDVD won't bring me to upgrade, esp. if there is (now) a handy working alternative.
About the CRC errors I encountered with some DVDs: I consider this "normal" as I'm still sort of evaluating what brand/type works best for my computers (data-only DVD) and stand-alone (movie DVDs).
sorry, if this sounds like I'm ranting -- I think I do <g> --, but starting with v5, Ahead went "far ahead" over what a cd-burning application is supposed to do. 5.5 worx fine for my needs and I like using it, but if they continue into that direction, I'll have to look for something else.

Have fun,
CirTap

[zacoz]

I just hit the burn-with dvddecr. button in PcgEdit testwise to see what happens, but then decided to burn the .iso file with Nero anyway.
But I'll certainly give it try next time. I don't mind using something else to burn the discs as long as it worx.It's not uncommon for me to only build the .iso from PgcEdit (with mkisofs), and then to later open DVDDecrypter manually to burn the .iso to disc. Simpler and quicker than the bloated Nero.

About the CRC errors I encountered with some DVDs: I consider this "normal" as I'm still sort of evaluating what brand/type works best for my computers (data-only DVD) and stand-alone (movie DVDs).I've found some disc's I recently purchased always produce CRC errors if I try to burn greater than 4400Mb, some others could reliable burn to 4420Mb, while my usual purchase of Verbatim's can handle 4464Mb (figures taken from DVDShrink preferences with relative % full reflected in PgcEdit's burn dialog). Adjusting my max limit once established for a given batch of disc's has saved me quite a few coasters.

[CirTap]

I've found some disc's I recently purchased always produce CRC errors if I try to burn greater than 4400Mb, some others could reliable burn to 4420Mb, ...
hmm, interesting. I'll keep a eye on that!
I recall some note someplace that one should leave some "room" on the discs so I never packed it up to 4.7 anyway, but I can't remember if any of the CRC-errored discs hit the 4.4 barrier you experienced. All I know is that this mostly (not always) happens with -RW, regardless of the brand. A pile of Traxdata -R worked fine, both directly burned and via disc-image.
pretty tedious to elaborate what workx and what not :-(

but: thanx for the hint!

Have fun,
CirTap