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jraras
2005-03-09, 01:50 PM
What are the standards for physically trading and b&p'ing DVDs? There is so much good stuff here that physical trading in addition to downloading is a must, imo.

Does burning a DVD from the files provided in a BT here at TTD, then ripping it via Decryptor into the VIDEO_TS etc. files have the same negative effect of burning .wav's from FLAC onto a redbook CD and then EAC'ing them back to .wav? Or does the DVD format address this problem so it is a moot point?

I guess the practical issue I'm trying to deal with is if I should burn data discs and DVD's of all my downloaded DVD's. Also, when doing a trade or b&p should one send a data disc with the contents of the torrent, or an actual DVD that is ready to be popped into a player and watched?

Thanks in advance (btw, I checked the FAQ, but couldn't find anything pertaining to this specifically for DVD, just stuff on audio). FWIW, I'm using windoze boxes (xp and 2k) and have decrypter and nero for software pertaining to DVDs.

best,
Jim :hmm:

U2Lynne
2005-03-09, 02:12 PM
When you burn a DVDR, the VIDEO_TS folder in the burned DVDR should have the *exact* same contents as the VIDEO_TS folder on your harddrive. In other words, it should not be changed in anyway from burning. You should be able to run your md5 checksum on the burned disc and it should pass. (However, I am hearing of some problems when using Nero and burning as a Video DVD that it sometimes changes the IFO and BUP files). So, you should not have to 'archive' your VIDEO_TS folder as well as burn your viewable DVDR.

As for trading DVDs, I have sometimes asked for a Data DVDR simply because I wanted two (or more) shows that were small in size and so if just burned as Data I could get them all on one DVD instead of two (or more) viewable DVDRs. This is really something that needs to be worked out between the two parties involved in the trade/b&p.

jraras
2005-03-09, 02:55 PM
So, if done with decrypter the files ripped from a viewable DVDR should be identical and pass the md5, that's what i'm hearing right?

Also, do people typically specify what type of DVDR (plus or minus) they use prior to a b&p or trade?

thanks!!
Jim :wave:

U2Lynne
2005-03-09, 03:12 PM
So, if done with decrypter the files ripped from a viewable DVDR should be identical and pass the md5, that's what i'm hearing right?
Yes, they should (except as I noted above, sometimes if you burn the DVD as a video DVD, Nero will convert the IFO and BUP files but will leave the VOBs alone).

Also, do people typically specify what type of DVDR (plus or minus) they use prior to a b&p or trade?

thanks!!
Jim :wave:
Yes, you should because some people can only burn plus or minus and some people can only read plus or minus (for instance, I can read plus or minus but only burn to minus).

jraras
2005-03-09, 08:18 PM
[QUOTE=U2Lynne]Yes, they should (except as I noted above, sometimes if you burn the DVD as a video DVD, Nero will convert the IFO and BUP files but will leave the VOBs alone).

OK, well I just checked a video DVD I burnt with GEAR, after d/l'ing the files from TTD. The results: upon ripping (using DVD decrypter) and checking the md5 the VOBs are fine, but the IFO and BUP are NOT--ala the claims made against Nero seem to be true w/ GEAR as well. Has anyone else experienced this with GEAR?

So, now I'm trying to burn the actual file structures that I dl'd from TTD to a video DVD using DVD Decrypter, but in file mode I can't seem to burn a disc. THe only option I see for 'write' (or burning) is in ISO mode and since we all d/l from TTD in file and people are using this to burn here, I must be missing something... no?

I'm a pretty anal guy from the audio world, so i test stuff like this to make sure all md5's match, etc and that I have the correct filesets in order to help with reseeding down the road. But, with Nero, GEAR and who knows what else changing IFO and BUP it probably isn't far fetched to guess that a lot of the physically traded/b&p'd stuff will actually NOT match the md5's of the torrents exactly, unless the trade/b&p occurs on data dvd. This seems like an issue to me... perhaps I'm paranoid.

thanks AGAIN
Jim :wave:

h_vargas
2005-03-09, 08:33 PM
this is why i use RecordNow to burn DVDs. it does *not* manipulate MD5s, info files, BUPs/IFOs, etc.

ever since around version 5.5. of Nero, i've read of it being problematic with burning DVDs... at first, it was what type of DVD compilation to use (UDF or DVD-Video...) so the burned DVD would play on a settop DVD player. now with the talk of Nero manipulating BUPs and/or IFOs on the DVD video disc, i'm not too surprised. i will say this, the video DVDs that i have burned with Nero 6.3 (i think that's the version i have) work fine on my settop players. but i still trust RecordNow for my data DVD archived discs and use it most of the time anyway, as it accepts the VIDEO_TS folder no matter what type of file is in there. (some authoring programs put in other files, such as layout a.k.a project/.LAY files, and Nero gives an error every time i try to burn a VIDEO_TS folder with said file types, which is just an annoyance to click "OK" to disregard the file every time.)

i think DVDDecrypter is god for burning. but like jraras, i never found an option for burning anything other than ISO files with DVDDecrypter. :( if they included that in an updated version, i'd probably dump RecordNow. the fewer programs i can get away with using, the better.

jraras
2005-03-09, 09:02 PM
So, basically if I want to be 100% sure that I'm spreading and receiving filesets that will check with original TTD md5's the only way to assure that is to trade/b&p/archive data discs of the filesets, not just the video DVDs. (analgous to how we all archive our data discs full of FLACs and not CDA's)

Bah! Makes snail-mail transactions quite the predicament, almost more than it's worth, since it seems like a lot of people archive and trade video DVDs as opposed to the filesets that comprise them.

:confused:

JR

this is why i use RecordNow to burn DVDs. it does *not* manipulate MD5s, info files, BUPs/IFOs, etc.

ever since around version 5.5. of Nero, i've read of it being problematic with burning DVDs... at first, it was what type of DVD compilation to use (UDF or DVD-Video...) so the burned DVD would play on a settop DVD player. now with the talk of Nero manipulating BUPs and/or IFOs on the DVD video disc, i'm not too surprised. i will say this, the video DVDs that i have burned with Nero 6.3 (i think that's the version i have) work fine on my settop players. but i still trust RecordNow for my data DVD archived discs and use it most of the time anyway, as it accepts the VIDEO_TS folder no matter what type of file is in there. (some authoring programs put in other files, such as layout a.k.a project/.LAY files, and Nero gives an error every time i try to burn a VIDEO_TS folder with said file types, which is just an annoyance to click "OK" to disregard the file every time.)

i think DVDDecrypter is god for burning. but like jraras, i never found an option for burning anything other than ISO files with DVDDecrypter. :( if they included that in an updated version, i'd probably dump RecordNow. the fewer programs i can get away with using, the better.

Five
2005-03-09, 09:34 PM
Bah! Makes snail-mail transactions quite the predicament, almost more than it's worth, since it seems like a lot of people archive and trade video DVDs as opposed to the filesets that comprise them.

:confused:

JR
Well it was the same a few years ago with audio cdrs. I've got over 100, probably 10-20% having clicks or pops somewhere on them that have crept in during copying and ruined their tradeability and sometimes also the listenability.

If somebody won't take data dvds in a mail trade then perhaps you could email them the artwork, md5s & info via email to verify their files with & pass along. And also verify the md5s on the video dvd before you send it out.

Another big issue for me is whether the VIDEO_TS folder needs to be altered or not (as Nero 6.3 does) in order to play on all standalones when burned.

RainDawg
2005-03-10, 09:23 AM
Just to chime in here....

The way around these problems is to burn with Nero as a data disc, but with a VIDEO_TS and a blank AUDIO_TS folder. If the VIDEO_TS folder (which is what you'll download from TTD) was authored correctly, this will still play in 99% of standalone players fine. Nero seems to alter the info files to perfectly match one standard, but it's not necessary.

So the answer to the question is yes, burn it as a data disc. But note that if you observe the rules, you won't need to sacrifice standalone playability with then disc. And as a data DVD, it'll exactly match the md5s on all files before and after burning unless there has been a burn error.

Oh, and yes, do use DVD Decrypter for this, as it's the only one that really does good error-checking on the files as they are extracted and will throw up an alarm if something goes wrong. Of course, if somethign does go wrong, your md5 will fail, but it's always nice to have a second layer of checking.

4candles
2005-03-10, 12:34 PM
Just to chime in here....

The way around these problems is to burn with Nero as a data disc, but with a VIDEO_TS and a blank AUDIO_TS folder. If the VIDEO_TS folder (which is what you'll download from TTD) was authored correctly, this will still play in 99% of standalone players fine. Nero seems to alter the info files to perfectly match one standard, but it's not necessary.


Sadly, I don't think it's as simple as that - and I would be surprised if 99% of all DVD players could play a VIDEO_TS folder burned in data mode.

When a DVD is authored, the IFO files contain "relative sector pointers" to other files on the DVD. Hardware DVD players use these pointers to locate the content on the DVD - it's only the "VIDEO_TS.IFO" file that a hardware player will actually look for by name. After that file has been found, everything is based on sectors, not files.

In order for the sector pointers to point to the correct parts of the correct files, the files must be ordered correctly on the DVD - and this is not alphabetical order, which is probably how Nero burns data DVDs.

A typical VIDEO_TS folder on a correctly burned DVD would have the files located in the following order:

VIDEO_TS.IFO
VIDEO_TS.VOB
VIDEO_TS.BUP
VTS_01_0.IFO
VTS_01_0.VOB
VTS_01_1.VOB
VTS_01_2.VOB
VTS_01_0.BUP
VTS_02_0.IFO
VTS_02_0.VOB
VTS_02_1.VOB
VTS_02_0.BUP

Notice that the order is IFO -> VOB -> BUP which is where the alphabetical sorting fails.

This is why DVDs burnt as data discs shouldn't work - it's simply a matter of the files being placed on the disc in the wrong order, so the pointers are no longer pointing where they should be. It's possible that by co-incidence that some or even all of the pointers could still point to the right place, but it isn't guaranteed.

Under Linux, the "mkisofs" program understands the .IFO files, and when you ask it to generate a DVD-Video compliant .ISO file for burning a DVD, it uses the pointers in the IFO files to decode where the files should be placed on the DVD.

Nero may well have it's own views on where files should go on a DVD (which could be different to the decisions made by the DVD Authoring program), and change some of the pointers in the IFO files. This is probably even more likely for DVDs authored using a standalone DVD recorder - I've seen some very odd structures being generated by standalone DVD recorders.

An interesting experiment (which I can't do as I don't use Windows) would be to burn a DVD in DVD-Video mode using Nero, copy the files back the hard disk, and then burn another copy of the DVD and see if Nero changes files that it has already changed.

If it turns out that Nero does indeed create MD5-identical burns after at least one generation, and considering the fact that Nero is more or less the de-facto standard for DVD burning, maybe a solution would be for seeders to pass the files through Nero before seeding.

Another solution (if it's only the IFO files that are being changed by Nero), would be to burn those (along with the torrent's text file and original MD5 checksums) in a seperate folder on the DVD. When extracting the DVD for trading, you could just copy the VOBs from the VIDEO_TS folder, and everything else from the data folder.

U2Lynne
2005-03-10, 01:04 PM
Every single DVD I have burned has been done using the Data - DVD-ROM (UDF) tab. I then name the DVD and place the VIDEO_TS and AUDIO_TS folder in the window and burn it. I've never had any problems with this method and I have burned a *lot* of DVDs! Of course, I'm talking about on my Mac using Toast, but I've heard of many people burning DVDs as a Data DVD using Nero and I haven't heard of any problems using that method (except for lots of user errors ;) ).

(image of Toast contents before a burn (http://u2lynne.sandsmuseum.com/images/toast.gif))

Five
2005-03-10, 06:23 PM
An interesting experiment (which I can't do as I don't use Windows) would be to burn a DVD in DVD-Video mode using Nero, copy the files back the hard disk, and then burn another copy of the DVD and see if Nero changes files that it has already changed.
I was thinking about this, too.

4candles
2005-03-10, 07:29 PM
Every single DVD I have burned has been done using the Data - DVD-ROM (UDF) tab. I then name the DVD and place the VIDEO_TS and AUDIO_TS folder in the window and burn it. I've never had any problems with this method and I have burned a *lot* of DVDs! Of course, I'm talking about on my Mac using Toast, but I've heard of many people burning DVDs as a Data DVD using Nero and I haven't heard of any problems using that method (except for lots of user errors ;) ).

(image of Toast contents before a burn (http://u2lynne.sandsmuseum.com/images/toast.gif))

It wouldn't surprise me if even in "data mode" Toast (and maybe even Nero) did the right thing with a VIDEO_TS directory and ordered the files correctly. It doesn't do any harm, so would seem to be sensible behaviour.

But the only tool I know that will actually tell you the order files are located on a DVD is "isoinfo" (a Unix command-line program that comes as part of the "cdrtools" package).

jraras
2005-03-13, 03:11 PM
Every single DVD I have burned has been done using the Data - DVD-ROM (UDF) tab. I then name the DVD and place the VIDEO_TS and AUDIO_TS folder in the window and burn it. I've never had any problems with this method and I have burned a *lot* of DVDs! Of course, I'm talking about on my Mac using Toast, but I've heard of many people burning DVDs as a Data DVD using Nero and I haven't heard of any problems using that method (except for lots of user errors ;) ).

(image of Toast contents before a burn (http://u2lynne.sandsmuseum.com/images/toast.gif))

I actually just tried this using the Veritas RecordNow DX chinzy software that came with my external Sony drive a few years ago and the data DVD I burned, per Lynne's method, is currently working fine in a $99 JVC DVD player... I guess I can't vouch for the readability of 99% of players, but it's working on mine.

Also, I looked at the decrypter of this disc and one I burned as a 'video DVD' in Nero and both of them listed the files in alpha order (BUP first), so does this really matter as was previously mentioned here?

If the readability isn't an issue, this should clearly be the preferred way of burning filesets to DVD, as their is no editing/changing/amending of the real files and md5's will continue to checkout.

Jim

jraras
2005-03-13, 07:40 PM
Hey all,

Been playing around with filesets and burning different ways all day and I just thought of something: why not make an "AUDIO_TS" folder mandatory in the parent folder of all DVD seeds? That way the fileset that results from the torrent could be burned "as-is" using the data setting in the downloaders' software, and the "AUDIO_TS" folder (which will be blank) will be included in the md5. For people burning using 'video DVD' mode, it shouldn't harm anything.

I must be missing something, because it seems too easy.

Jim

ffooky
2005-03-13, 09:02 PM
I believe empty directories can cause problems with some BT clients.

ozzyzak
2005-03-13, 09:34 PM
Maybe I'm using the wrong burning software, but I don't think I've been able to burn a video DVD in data mode. I've tried it under Linux as a data DVD with the VIDEO_TS and AUDIO_TS folder and it wouldn't play in my standalone.

PaulHarald
2005-03-20, 08:24 PM
This is a VERY interesting thread. I use Toast on a Mac and can confirm the same .ifo and .bup changing on some - but just some - DVDs. The guy saying he never had a problem with Toast and his Mac may be right, but if he did a full "compare" (utilities menu in Toast) or did md5 checksum files of the original and the copy, he might find some files changing.

I posted this observation to the official Roxio (makers of Toast) forums and got these replies:

<quote>

Well, I can tell you that Toast does have to modify the IFO files so that the Offsets are correct.

...

I'm just guessing here and I haven't tried it myself, but I think this could be happening.

If someone writes a Video_TS folder directly to the HD from an authoring application, or an application that doesn't do it correctly the offsets could be off. When Toast writes the VIDEO_TS folder the offsets get corrected and the resulting VIDEO_TS folder would fail to verify and compare.

If the VIDEO_TS folder was first burned to a disc, then that VIDEO_TS folder was taken from the disc and saved to the hard drive, the offsets should be correct already. In this case, when the VIDEO_TS folder got burned in Toast, no changes would be needed and the disc would verify.

When burning DVD Dual Layer in Toast, the IFO also needs to be updated to set the break point correctly.

<end quote>

So there you go. Someone suggesting running discs through Nero to "rectify" them - well that might be it and maybe Toast does the exact same thing. Toast is the gold standard app for DVD burning on the Mac. Always trusted it and never had problems before md5 checking came along :-)

Actually, when using MacTheRipper (Mac ripping app) to rip a DVD, then burning, the .ifo and .bup files ALWAYS change, same thing if I save as disc image from Toast so it's not the burning it's the file handling. This may be an example of what the Roxio guys said about certain authoring apps. IMO Ripping should never be performed on region free unencrypted DVDs like the ones we are trading, they should just be copied.

This is a difficult problem we're discussing here, and I'm just a user, not an expert. I have even seen Toast being determined to change .VOB files (again and again when repeated on different Macs and after re-downloading) with some very few torrented DVDs on EZT so I wonder what that's all about. They play fine, but md5 checksums are of course altered, and people who doesn't check if it's a perfect clone won't know but it isn't.

I wish someone would get to the bottom of this one!

Cheers,

PaulHarald

feralicious
2005-03-20, 08:34 PM
For trading, why not just make an image then burn it. It should be identical and pass verification.

For initial burning I use RecordNowMax! and they have never failed to verify. And it allows me to put the info and md5 and artwork outside the VIDEO_TS folder so that the md5 is in place to run its check on all items.

What about torrenting image files? As long as it's not a proprietary image and can be handled by all systems is there anything wrong with that?

PaulHarald
2005-03-20, 08:50 PM
For trading, why not just make an image then burn it. It should be identical and pass verification.



It's not identical when made by Toast, and maybe that's the case with Nero as well. My guess is that it is, but I don't have a PC, just Macs.

The thing is: Toast makes these "necessary" (?) changes also when making a disc image. So it doesn't verify.

feralicious
2005-03-21, 01:12 AM
That's weird, the whole point of making an image is so that it is identical. Are you sure you're not copying on the fly?

U2Lynne
2005-03-21, 01:19 AM
Paul, are you burning a Data Toast DVD or a Video Toast DVD?

PaulHarald
2005-03-21, 06:37 AM
Read my posts, especially the long one.

I am not even burning so no - I don't copy on the fly. While making a disc IMAGE (saved to the hard drive) with toast using a VIDEO_TS and an AUDIO_TS folder as source files, this happens with some DVDs. Yes, Nero and Toast seem to "correct" the .ifo and .bup files on some DVDs and the Roxio guy confirmed this.

And yes - it happens no matter if I use the Data Toast DVD or a Video Toast DVD function. And I don't even have to burn to see what happens.

(Actually, the Video DVD function in Toast that I believe was introduced with 6.0.7 is actually just a menu enhancement that also adds an AUDIO_TS folder automatically if you haven't done so already. The actual file format used is the same (UDF). If you are talking about MAKING and not copying a DVD using Toast, then there is no way to compare anything, as Toast multiplexes any files thrown at it and this is obviously not the way to make a perfect clone).

Md5 checksum comparison using xAct or any other md5 tool, or the "compare" function in Toast will show that files have altered, and doing this on any of my Macs generates the exact same results again and again with the same VIDEO_TS fileset.

Five
2005-03-21, 10:39 AM
So if you burn a disc with Toast then copy the VIDEO_TS folder to your computer from that DVD, then burn again with Toast the files are not altered further, right?

feralicious
2005-03-21, 11:39 AM
Read my posts, especially the long one.

I am not even burning so no - I don't copy on the fly. While making a disc IMAGE (saved to the hard drive) with toast using a VIDEO_TS and an AUDIO_TS folder as source files, this happens with some DVDs. Yes, Nero and Toast seem to "correct" the .ifo and .bup files on some DVDs and the Roxio guy confirmed this.

And yes - it happens no matter if I use the Data Toast DVD or a Video Toast DVD function. And I don't even have to burn to see what happens.

(Actually, the Video DVD function in Toast that I believe was introduced with 6.0.7 is actually just a menu enhancement that also adds an AUDIO_TS folder automatically if you haven't done so already. The actual file format used is the same (UDF). If you are talking about MAKING and not copying a DVD using Toast, then there is no way to compare anything, as Toast multiplexes any files thrown at it and this is obviously not the way to make a perfect clone).

Md5 checksum comparison using xAct or any other md5 tool, or the "compare" function in Toast will show that files have altered, and doing this on any of my Macs generates the exact same results again and again with the same VIDEO_TS fileset.I said for trading, so that's assuming you already have it burned, make an image of it (the disc), then burn that. That should be identical. Of course you have to burn it initially.

PaulHarald
2005-03-21, 02:52 PM
Hi,

Well, keep most of what I burn on a HD but you are absolutely right:

If I already have it burned and make a copy, no errors ever:

(Copy to desctop, compare, burn to disc, compare again)

...but burning from my VIDEO_TS folders on my hard drive (I have a TB) generate the same errors every time.

Five
2005-03-21, 03:14 PM
It seems to me like these are the SBEs of the video world...

So I'm thinking a couple things:

-Once the changes are made with Toast & can be copied & recopied without further changes to the files, would these files be further altered by a program like Nero? It would seem to me that these files have been subtlely corrected in some way.

-Is there an app that can check a VIDEO_TS folder on a HD to see if it will need to be "fixed" and if so can this program also prepare the files in the VIDEO_TS folder so that they can be burned with any DVD burning program (like Toast or Nero) without any further changes being made?

am I onto something or is this just wishful thinking?

Paul, have you ever downloaded a DVD and burned it with Toast and found no errors introduced?

4candles
2005-03-21, 03:17 PM
One way to look at all this is to say that the DVD authoring process isn't complete until you have actually burned the VIDEO_TS folder to DVD.

So maybe the recommendation should be that DVDs are seeded from actual DVD copies, not from VIDEO_TS folders created by authoring software.

This is counter-intuitive for those coming from a CD-Audio, but there shouldn't be any risk of data corruption by addding a DVD generation into the lineage.

The only problem then would be if Nero and Toast (the two de-facto standard burning programs) have a different concept of what is right when they create the DVD image.

PaulHarald
2005-03-21, 08:52 PM
It seems to me like these are the SBEs of the video world...

So I'm thinking a couple things:

-Once the changes are made with Toast & can be copied & recopied without further changes to the files, would these files be further altered by a program like Nero? It would seem to me that these files have been subtlely corrected in some way.

-Is there an app that can check a VIDEO_TS folder on a HD to see if it will need to be "fixed" and if so can this program also prepare the files in the VIDEO_TS folder so that they can be burned with any DVD burning program (like Toast or Nero) without any further changes being made?

am I onto something or is this just wishful thinking?

Paul, have you ever downloaded a DVD and burned it with Toast and found no errors introduced?

This thread is getting somewhere, which I can't say for the same attempts to make some sense at videohelp.com Apple Discussions or at the Roxio forums... :-)

Yes, many torrented DVDs have been burned without anything changing. Typically the "authored by me this and that way" kind of DVDs. It's usually the "i got this in a trade by some guy" DVDs that has the .ifo and .bup files changing.

Example: All 3 DVDs in the Pink Floyd Anthology DVD set was shared at EZT. I burned them all without errors or changes to any files. Great. Then I went to the Harvested-weeds site and got the MD5 files posted at the site and compared. Everything checked out OK except for the two .ifo files and the two .bup files of disc 3 only. Disc 1 and 2 was a perfect match for all files, so the seeder obviously had good copies.

Now just out of curiosity, I downloaded Disc 3 again and checked. The files in question did not match the "official" md5, but it's a good copy and Toast ket the files pass without "correcting" anything. Strange thing.

But sometimes I get a DVD from a torrent that doesn't get corrected at all, and when played there is a pause at each chapter break. My guess is that it's a badly authored DVD or something and nothing to do with what we're discussing here.

So yes, I think you are on to something. But what's the final word? I don't know.

h_vargas
2005-03-22, 02:04 AM
For initial burning I use RecordNowMax! and they have never failed to verify. And it allows me to put the info and md5 and artwork outside the VIDEO_TS folder so that the md5 is in place to run its check on all items.

What about torrenting image files? As long as it's not a proprietary image and can be handled by all systems is there anything wrong with that?

rock on!! i do the same - use RecordNow Max... for both archived DVDs and Video-DVDs. works flawlessly for me, and never had an issue with a DVD not playing in a settop player. and the un-changed IFOs/BUPs are quite a bonus, apparently. :D

jraras
2005-03-22, 10:56 AM
rock on!! i do the same - use RecordNow Max... for both archived DVDs and Video-DVDs. works flawlessly for me, and never had an issue with a DVD not playing in a settop player. and the un-changed IFOs/BUPs are quite a bonus, apparently. :D

Wow, you guys are kicking butt on this discussion... glad I wasn't the only one who found the subject worthy of some bw.

FWIW, I'm using RecordNow Max too and getting perfect results and great playability (is that a word?).

As far as the .ifo and .bup changing, I obviously don't love the idea, as I'm an anal perfectionist who likes the md5's to check exactly... but these are just pointers and at the end of the day do not change the 'content' of the DVD, right? (please correct me if I'm wrong, I'm more of an audio guy in intellect) With that said, if the VOBs pass md5, then really you don't have a matching fileset, but you have the important/vital data, right?

Someone mentioned this issue being the SBE's of the video world and while the pointers to basically serve the same purpose--in my understanding--the editing of the ifo and bup files do not produce artifacts that degrade the watching/listening experience as SBE's do in the case of clicks between tracks on CD-A. So I agree, but to a varying degree ;)

best,
Jim

PaulHarald
2005-03-22, 05:22 PM
As far as the .ifo and .bup changing, I obviously don't love the idea, as I'm an anal perfectionist who likes the md5's to check exactly... but these are just pointers and at the end of the day do not change the 'content' of the DVD, right? (please correct me if I'm wrong, I'm more of an audio guy in intellect) With that said, if the VOBs pass md5, then really you don't have a matching fileset, but you have the important/vital data, right?

Someone mentioned this issue being the SBE's of the video world and while the pointers to basically serve the same purpose--in my understanding--the editing of the ifo and bup files do not produce artifacts that degrade the watching/listening experience as SBE's do in the case of clicks between tracks on CD-A. So I agree, but to a varying degree ;)

best,
Jim

Good points. I have sort of "decided" for myself that the .VOB files have to match, and not the .ifo and .bup files. I don't know enough about this matter to defend this decision though...

Could a faulty .ifo file introduce a pause/stalling of approximately 2 seconds between chapters on a DVD or would that be caused by something different? I have some DVDs with this happening. Would love to be able to correct it.

And another thing: If Toast/Nero actually does good to some DVDs .ifo and .bup files - I would not like to use a burning app that doesn't - but then again that's the whole basis of this discussion and I'm still puzzled...

h_vargas
2005-03-23, 04:52 AM
what i would like is to see a side-by-side comparison of the BUPs/IFOs from pre- and post-burning with these programs that do something to change the files. from what i know, IFO files generally are like "cue sheets" (well, they're info files to be precise) that tell a DVD player where chapter points are, what language(s) are on the DVD, region info, what functions are/aren't disabled on the remote control, blah blah.

so, i'd be interested to look at a side-by-side of the altered IFO vs. the original IFO, if someone cares to take the time to post them. (they would be very small files, since they're essentially text files of sorts... so it wouldn't take foreever to upload them to a server or anything.)

on another note, i will reiterate: RecordNow Max rules. the only time i use Nero to burn DVDs is when i'm burning a test DVD on a RW disc, because Nero doesn't make me erase the disc, i can just burn over the existing data (RecordNow won't let me do that).

gsmyth79
2005-07-16, 12:22 AM
Resurrecting this from the dead, with actual md5s to show from a recently torrented show, Phish 1997-02-18.

I burned disc 1 using DVD-ROM(UDF) with Toast Titanium. The .bup and .ifo files changed. I'm wondering of someone else can confirm this. original md5s (folder hierarchy is different but that doesn't matter):
000103302beea4d31408662447337e98 *set I\VIDEO_TS\VIDEO_TS.BUP
000103302beea4d31408662447337e98 *set I\VIDEO_TS\VIDEO_TS.IFO
c27fd02800c1a22261692bae9eb61f75 *set I\VIDEO_TS\VIDEO_TS.VOB
18ef947fbdf8cd5479154a052a68219c *set I\VIDEO_TS\VTS_01_0.BUP
18ef947fbdf8cd5479154a052a68219c *set I\VIDEO_TS\VTS_01_0.IFO
2d682bd0f81c8b84e08b9d56f309446d *set I\VIDEO_TS\VTS_01_0.VOB
9b152723abdf8755c7b467bb4ff8482c *set I\VIDEO_TS\VTS_01_1.VOB
a6014b3017207d5dc67036bdeebeea17 *set I\VIDEO_TS\VTS_01_2.VOB
09ecf641a66e64129521650c9e7420e2 *set I\VIDEO_TS\VTS_01_3.VOB
c095f88e1a3a53ef53d7072d2648e2e8 *set I\VIDEO_TS\VTS_01_4.VOB
99c35d80f37c6618aa9c56b5fdb3a231 *set I\VIDEO_TS\VTS_01_5.VOB
07c1e31de135bc0102e0da877acdca3c *set I\VIDEO_TS\VTS_02_0.BUP
07c1e31de135bc0102e0da877acdca3c *set I\VIDEO_TS\VTS_02_0.IFO
c27fd02800c1a22261692bae9eb61f75 *set I\VIDEO_TS\VTS_02_0.VOB
8e147fa360421cf2f4d138d7f9d68efc *set I\VIDEO_TS\VTS_02_1.VOB

md5s from the burned disc, only .bup and .ifo different:
b442bc0bd80e36a0e3fb0462a38cd27d *VIDEO_TS.BUP
b442bc0bd80e36a0e3fb0462a38cd27d *VIDEO_TS.IFO
c27fd02800c1a22261692bae9eb61f75 *VIDEO_TS.VOB
18ef947fbdf8cd5479154a052a68219c *VTS_01_0.BUP
18ef947fbdf8cd5479154a052a68219c *VTS_01_0.IFO
2d682bd0f81c8b84e08b9d56f309446d *VTS_01_0.VOB
9b152723abdf8755c7b467bb4ff8482c *VTS_01_1.VOB
a6014b3017207d5dc67036bdeebeea17 *VTS_01_2.VOB
09ecf641a66e64129521650c9e7420e2 *VTS_01_3.VOB
c095f88e1a3a53ef53d7072d2648e2e8 *VTS_01_4.VOB
99c35d80f37c6618aa9c56b5fdb3a231 *VTS_01_5.VOB
07c1e31de135bc0102e0da877acdca3c *VTS_02_0.BUP
07c1e31de135bc0102e0da877acdca3c *VTS_02_0.IFO
c27fd02800c1a22261692bae9eb61f75 *VTS_02_0.VOB
8e147fa360421cf2f4d138d7f9d68efc *VTS_02_1.VOB

It would be great if someone could confirm this with Toast and especially Nero. I'm emailing the seeder to see if he ripped these files off a data DVD or a "playable" DVD (ie burned with Nero or Toast DVD-ROM(UDF)). This may get to the root of the problem.

gsmyth79
2005-07-16, 12:44 AM
I also contacted the seeder to see whether he seeded "data" files or whether he seeded a rip from a "playable" DVD.

Five
2005-07-16, 01:39 AM
I noticed the same thing recently when I sent two DVDs to a guy in Holland... he doesn't have a DVD burner so it was very, very important that I burn a playable DVD for him so he could play it on his standalone. One was taken from a video DVD, when I burned that one I generated .md5 checksums from it and they matched exactly. The other was downloaded from STG and when I burned it the BUP and IFO were different but the VOBs were identical. I emailed the guy the artwork, .txt files and .md5s. The disc with the wrong checksums would be considered bastardized in some way, but are they really?

this was posted over here (http://www.thetradersden.org/forums/showthread.php?t=9456):
Given that the big beasts (Nero & Toast) both sometimes make these changes, might it not be sensible for people to make a separate md5 of the VOBs as well as one of the entire contents of the VIDEO_TS folder ? Any differences in BUPs and IFOs are likely to be imperceptible but would prevent verification/comparison in much the same way as changing tags does with an audio files/wholefile md5 set.

Edit: forget it...talking bollocks as usual :-)
Now is this a good or a bad idea? At first read it seemed to me like a great idea. As I was mentioning earlier in this thread, it would be good to know if toast and nero make the same changes when they "fix" the BUP and IFO files, if after the first time it is burned to video dvd the checksums stay the same on mac or pc then this would almost be like fixing SBEs, right? What are the advantages and/or drawbacks to allowing BUP and IFO files to be altered, so long as the VOB checksums remain the same?

gsmyth79
2005-07-16, 12:15 PM
I think as long as the .vob files are the same it probably doesn't make any difference. It's pretty annoying for me being an "md5 freak" and all. It seems like there's no way around this. I'm just going to keep the people I trade with informed if I'm giving them a disc with a different .bup and .ifo than the downloaded one.

I think an md5 of the entire contents' md5 is necessary to make sure the download is correct, but I don't think people should swet the altered files. For me it happens very infrequently, and I make a note of it in my records.

4candles
2005-07-16, 01:10 PM
I think as long as the .vob files are the same it probably doesn't make any difference. It's pretty annoying for me being an "md5 freak" and all. It seems like there's no way around this. I'm just going to keep the people I trade with informed if I'm giving them a disc with a different .bup and .ifo than the downloaded one.

I think an md5 of the entire contents' md5 is necessary to make sure the download is correct, but I don't think people should swet the altered files. For me it happens very infrequently, and I make a note of it in my records.

I agree - it's annoying, but seems to be unavoidable (unless we trade .iso images, which then cause their own problems).

Given that you've made notes about this, have you noticed any patterns in which DVDs have their IFO files modified when burning to DVD? i.e. do you know which DVD authoring programs were used for those DVDs?

If anyone has a set of "before" and "after" IFO files that are changed by Nero or Toast, I would be very interested in getting a copy to analyse.

gsmyth79
2005-07-16, 05:29 PM
4c-

I can post the .ifo from the discs I burned of Phish 2.18.97 but I don't have the original file anymore.

pawel
2005-07-16, 05:41 PM
Question to Mac folks: can you read a data DVD (containing i.e. flacs, txts, jpgs) burnt under Windows? I think that such disc is readable without any problem, but I like to be sure. I had once a trade with a Mac guy who cliamed that he cannot read a "PC DVD disc". Of course the disc was burnt correctly - checked with md5 and CDCheck.

4candles
2005-07-16, 05:46 PM
4c-

I can post the .ifo from the discs I burned of Phish 2.18.97 but I don't have the original file anymore.

Does anyone reading this have the original IFO files from that show?

I think they would only be useful if I had both the "before" and "after" IFOs.

It's not convenient, but maybe one solution would be to create a ZIP file containing the original downloaded IFO files, and add that zip file to the DVD (outside of the VIDEO_TS folder) before burning.

That way, you would be able to restore the original downloaded files to your HD, and compare the MD5 checksums, without the need for burning two copies of the show.

U2Lynne
2005-07-16, 06:05 PM
2-19-97 was seeded by SYF8. I can PM him and see if we can get the ifo files. Or, if someone has Azureus, then you can just grab those files off the torrent. Actually, I'm doing that now and I'll post them here.

As for reading a DVD written by a PC on a Mac, I have been able too. I think what matters is how it is burned. I know in Toast, when I make a data DVD (for flacs, etc), I choose the Advanced tab and hit "Mac & PC". But, there is another option for "Mac Only". Perhaps the person who says he can't read a PC produced DVD once got one that was written wrong.

4candles
2005-07-16, 08:20 PM
2-19-97 was seeded by SYF8. I can PM him and see if we can get the ifo files. Or, if someone has Azureus, then you can just grab those files off the torrent. Actually, I'm doing that now and I'll post them here.


Thanks. Did you mean to write 2-19-97? gsmyth79's DVD was 2-18-97. That would cause the MD5s to be different :)

I don't have a BT client that lets me to selectively download files, so I can't do it myself.

gsmyth79 - can you post the modified IFO files?

4candles
2005-07-21, 12:49 PM
I've now compared the "VIDEO_TS.IFO" file from the DVD burned using toast by GSMYTHE (thanks to Graham for a copy of the file) with the original torrented on this site.

There is only one byte in the IFO file which is different between the two versions - but this is obviously enough to change the MD5 checksums.

The difference is in the VMG_PTT_SRPT (Video Manager Title Play Map Table) and is the value of the "Title set starting sector" for title 1.

What that means is that there is absolutely no difference in the content of the two DVDs, just that Toast is positioning the files on the DVD in a different way to that predicted by the DVD authoring program (or by the first program to burn those files to DVD). Because of that, it has needed to adjust one of the sector pointers in the VIDEO_TS.IFO file for hardware players to still play it properly.

You could compare this problem with MD5 checksums of WAV files - two WAV files could contain slightly different headers (and therefore have different MD5 checksums), but the PCM data inside the WAV file (the "FLAC fingerprint" or "shntool MD5") could be identical.

So the solution would be to calculate MD5 checksums of just the important data inside the IFO and VOB files - but that's not an easy thing to do, especially as the DVD specifications are not published.

U2Lynne
2005-07-21, 01:00 PM
Darn, I forgot to post those ifos for you. Sorry.

Very interesting what went on. But, as you said, a solution to it is difficult. Too bad we don't have something similar to shntool md5s for them.

gsmyth79
2005-07-21, 01:02 PM
What that means is that there is absolutely no difference in the content of the two DVDs, just that Toast is positioning the files on the DVD in a different way to that predicted by the DVD authoring program (or by the first program to burn those files to DVD). Because of that, it has needed to adjust one of the sector pointers in the VIDEO_TS.IFO file for hardware players to still play it properly.


Thanks for checking that out 4c! So what I'm getting here is that it really doesn't make a difference; the DVDs should play just fine. Right?

I'm just keeping accurate records for myself at this point. For example, places that do a lot of vining like Phishhook don't have any standards at all. As long as the DVDs play they don't care. Sometimes the vines are sent as data and sometimes as playable DVDs. So I just note it and move on.

Lou
2008-02-26, 12:31 AM
Well, I scoured the internet for this problem and lo and behold, I ended up here. I just noticed that on one of my DVD's, the IFO and BUP failed verification when burned to video with Nero, but the VOB's were fine. Glad to see it's not a big deal.

AAR.oner
2008-02-26, 05:10 AM
Well, I scoured the internet for this problem and lo and behold, I ended up here. I just noticed that on one of my DVD's, the IFO and BUP failed verification when burned to video with Nero, but the VOB's were fine. Glad to see it's not a big deal.

correct, the ifo/bup files were changed due to Nero "fixing" a structure issue...none of your actual video content has changed tho is the vob's check out fine