Rebuild from PAL > NTSC?

[Delphin]

I have searched the forum unsuccessfully for information about using DVD Rebuilder to create a NTSC backup from a PAL source.

I am sure that this must have come up before but I can't find much info.

I found this thread . . .

http://forum.doom9.org/showthread.php?t=76227

but that was some time back and I did not know if the situation has changed or if other tools have become available.

As I see it there are 3 main issues.

1. Need to pause the Rebuild process after encoding all the video resources to m2v files so that 29.97 pulldown can be applied to the 25fps video elementary streams to make them NTSC playback compatible.

2. Need to make DVD Rebuilder think that these new streams are valid and that it is working on a NTSC project so that it will build proper nav packets into the streams and create valid NTSC VOBfiles.

3. Need to adjust scale factors for buttons, highlights hot spots etc in original DVD’s IFOs to prevent the control menus from being screwed up and all out of position when overlaid over the newly converted NTSC menu frames.

Is this practical in DVD Rebuilder or would some other tool be better?

I could probably re-encode the video and re-author the DVD manually but the prospect of doing all the rescaling patches to prevent the control buttons in menus from shifting around is daunting to say the least. It would help a lot if I could just find a tool that would automate the conversion of the menus from PAL to NTSC and do the necessary IFO file patches to correct for the change from a 720x576 PAL control grid to a 720x480 NTSC control grid.

I know very little about Rebuilder at this point, so I am not sure if this has become possible, but am looking to find a good tool (or tools) to automate the above steps and would appreciate any ideas.

Any thoughts??? :confused: :confused: :confused:

[jdobbs]

I'm not sure if anyone has come up with a process... if so I haven't heard of it. There are lots of factors that would make it difficult. For example -- DVD-RB does almost no manipulation of the audio/subpicture streams, and that's something that would definitely be required for conversion.

[Carpo]

http://forum.doom9.org/showthread.php?t=97303&highlight=ntsc+pal - dunno if that will help - obviously thats pal to ntsc - never now do the steps the other way around might work ;D

[jptheripper]

i have done alot of movie only pal to ntsc.

there is an awesome pulldown toll (dgpulldown) that basically flags a 25fps stream to 29.97fps (after converting from 720x576 to 720x480). I then author the audio and subs as normal with muxman. no adjustments need to be done to the subs or audio b/c, in essence, you are still working with a 25fps file so the timings are all correct

menus are the hard part, button locations get all screwy and and its not a simple m2v file. However i thought numenu4u could do pal to ntsc for menus.

if you convert the menus to a 29.97 stream at 720x480 with numenu4u, then process all the titlesets with rebuilder from 720x576 25fps to 720x480 25fps, all you would need is to alter the flag files and do some "smart" rebuilding.

[Delphin]

I'm not sure if anyone has come up with a process... if so I haven't heard of it. There are lots of factors that would make it difficult. For example -- DVD-RB does almost no manipulation of the audio/subpicture streams, and that's something that would definitely be required for conversion.

Actually there is no Audio sync correction required at all if you use the method used in Donald Graft's DGpulldown. He uses a modification of the standard 23.98 > 29.97 conversion to FLAG the MPEG file using RTF and BFF flags so that the playback rate is changed from 25fps to exactly 29.970... (30000/1001).

This keeps the audio in perfect sync without having to actually re-encode a single byte of the video or audio (just change a few header flags in the video stream only).

I have already used DGpulldown several times and the correction works perfectly.


menus are the hard part, button locations get all screwy and and its not a simple m2v file. However i thought numenu4u could do pal to ntsc for menus.


Yes I stumbled onto NuMenu4U last night, and if it lives up to it's promise it should be able to shrink the menus while doing the necessary corrections (at least I hope so).

Maybe Rebuilder could just juggle these two external applications (assuming their authors can provide a simple scripting or command line parameter interface).

Currently NuMenu4U requires Scenarist (which isn't very practical for most users), but the author is working on a MuxMan port that should be a bit easier to deal with.

Actually, Rebuilder must already included a stream mux to do what it does now so maybe jdobbs could look at the DGpulldown and NuMenu4U code and just internally code these functions ;)

[Zeul]

Muxman is already fully supported for VIP users

[jptheripper]

great to see you on this thread zuel. When numenu4u vip do a pal-ntsc conversion on all menus, how does it reference the (presumably) still pal stream?

[Video Dude]

Don Graft's DGPulldown is the most feasible since the audio would not have to be streched and re-encoded to be kept in sync. It works by adjusting flags in the video stream, no need to process the audio.

http://neuron2.net/dgpulldown/dgpulldown.html

Perhaps DVD-RB can use this method to do a PAL->NTSC in movie only mode (since DVD-RB does not currently touch menus).

[Zeul]

@jptheripper
The video aspect is changed (to reflect NTSC), audio length altered (if the settings require it), and the subs resized. On authoring, the button positions are all changed to correspond with the new subs. The menu stuff in the ifo is altered also.

[jptheripper]

sweet thanx for the info, donating to become vip after payday :)

[jdobbs]

Actually, Rebuilder must already included a stream mux to do what it does now so maybe jdobbs could look at the DGpulldown and NuMenu4U code and just internally code these functions Inserting pulldown parameters to make 25fps play back as 29.97 should be easy enough... but I hesitate to do so. I try to stay within DVD spec -- and I'm not sure all players would accept it.

[jptheripper]

well i dont think donald graft has run into any problems, there is a huge thread on dgpulldown on the boards.

right now i am content to do it the hard way , and have jdobbs keeping tweaking the ilvu code
:)

[jdobbs]

DG is, of course, a genius. But prudence can be an asset also. Just because you can do something doesn't always mean you should.

[jptheripper]

wow, thats the only time you will ever hear that out of a programmer

[jdobbs]

LOL -- that's way too close to the truth. :D

[Delphin]

Inserting pulldown parameters to make 25fps play back as 29.97 should be easy enough... but I hesitate to do so. I try to stay within DVD spec -- and I'm not sure all players would accept it.

I'm starting to get that Dustin Hoffman / Marathon-Man feeling,

“Is is safe?” . . .

“I don’t kno. . . Argaaaaa”

“IS IT SAFE? . . .”


Actually in this case, I think it IS ‘safe’.

Let’s think about ‘pulldown’ as it’s used on commercial DVD’s . . .

Remember DG wrote DGindex, and when you use it to check a commercial disk you rarely get a perfect "100% FILM" score.

I think that's because a lot of commercial disks have 'discontinuities' in the 3:2 pulldown sequence, varying from simple 'drop frame' operations to really neat stuff like using 'real' 29.97 for extras and pulldown processed 23.98 for the main film.

I think that , if you check again, you will find that the ONLY thing the DVD standard guarantees about a 29.97 pulldown stream, is that, after the flags are processed (inverse pulldown), the stream will be 29.97 (actually 30000/1001) fps.

That’s it! Reading more into it would just be an invitation to get into trouble.

So, as far as I can tell, the only way a DVD player could get into trouble with the DGpulldown 25fps PAL conversion material would be by stupidly assuming that the presence of RFF/TFF flags automatically means that a perfect 3:2 pulldown from 23.98>29.97 is going on. (RFF/TFF= Repeat First Field/Top Field First for those of you who don't speak DVD):)

Given the goofy RFF/TFF stuff which apparently already goes on with commercial disks (see my above comment about the lack of 100%Film verification values for a lot of commercial DVD's), I doubt any such stupid hack would get out of BETA TEST at the player manufacture (because it would cause problems with a LOT of commercial DVD's).

Also, being an uncommonly wise programmer :) [Just because you can do something doesn't always mean you should] :) , you know that most 'stupid hacks' happen because they allow some enticing shortcut, but in this case I can't see any real "benifet" that a player software designer could derive from assuming that RFF/TFF must mean a 23.97 source. The thing that would discourage such a hack is that the EASY path is to ONLY assume that RFF/TFF is just what the standard guarantee’s, a stream that, AFTER the flags are processed, will play EXACTLY 29.97 (that way we don’t even have to worry about the REAL frame rate, how convenient!).

So, given the way most players probably do there their buffer management, I doubt they even know something is going on.

The fact is, this is SUCH A CLEAVER IDEA that if the folks at Sony Media, Scenarist, etc, had come up with it, then it would undoubtedly be the subject of yet another brainless 'software patent' (so thank god it was developed collaboratively here at doom9 and made publicly available).

So, the bottom line is, I can't see why a player would have any incentive to process the stream in a way that would cause a problem, and, in a dozen trials haven’t found a single one that does, so the DGPulldown algorithm is almost certainly ‘SAFE’ (read that as ‘less goofy' than a lot of other hacks that we do here at doom9) :) :) :)

[Rockas]

.... plus... the conversion will be done only by those who wants too ;)
... but ... I think that NTSC->PAL would be nice, too :) ... not that I need that... I only use $50 players lol

[hutch1711]

if you convert the menus to a 29.97 stream at 720x480 with numenu4u, then process all the titlesets with rebuilder from 720x576 25fps to 720x480 25fps, all you would need is to alter the flag files and do some "smart" rebuilding.
Just how would you go about converting the titlesets from 720x576 25fps to 720x480 25fps? Since the menus have been converted to 720x480 29.97 fps wouldn't you want the titlesets converted to 29.97 fps also? Can someone provide an explaination as to why NuMenu4u converts the pal source menus to 720x480 29.97fps, then tags this new menu to the rest of the unconverted titlesets that are still at 720x576 25fps? There seems to be a veiled suggestion that you can process it with DVD Rebuilder, however the only thing I see that accomplishing is to reduce the file size to fit on 4.7GB dvd, with no change to either the menu or titleset streams. :confused:

[jptheripper]

Just how would you go about converting the titlesets from 720x576 25fps to 720x480 25fps? Since the menus have been converted to 720x480 29.97 fps wouldn't you want the titlesets converted to 29.97 fps also? Can someone provide an explaination as to why NuMenu4u converts the pal source menus to 720x480 29.97fps, then tags this new menu to the rest of the unconverted titlesets that are still at 720x576 25fps? There seems to be a veiled suggestion that you can process it with DVD Rebuilder, however the only thing I see that accomplishing is to reduce the file size to fit on 4.7GB dvd, with no change to either the menu or titleset streams. :confused:


what i meant by smart rebuilding is:

yes numenu4u would properly prep the menus

in rebuilder, adding a lanczosresize to 720x480 in the filter menu would resize the video to 720x480, keeping it at 25fps

dgpulldown can then be applied to the m2v titlesets (MANUALLY) to flag them to 29.97

the step that is NOT functional yet is then having rebuilder rebuild the new titlesets recongizing that the framerate has changed. this functionality is currently not available.

[hutch1711]

jptheripper, I'll give your suggestions a try. :thanks: I appreciate your prompt reply.

[Zeul]

hutch1711
What would be the point of NOT putting the menu files back into the main folder? Without the menu files (regardless of format) RB would assume that there were no menus, so the bitrate for the titles would be incorrect.
RB needs a FULL folder to work from.

[hutch1711]

Hi Zeul, please excuse my ignorance, but I hope to learn by asking what probably seem like stupid questions. Am I correct in my assumption that the dvd created by NuMenu4u from a pal source, that coverted the menus to ntsc format, requires further "rebuilding" because of the pal and ntsc format mix? If that is the case, I guess what I was asking is wouldn't you want to keep the remaining unconverted pal files separate from the new ntsc menu files created by NewMenu4u, and combine then together after you have converted the remaing pal files to ntsc?

[jptheripper]

you cant combine, you have to reauthor, as all the pointers are different

[hutch1711]

you cant combine, you have to reauthor, as all the pointers are different
Correct! Sorry wrong terminology used. :p

[DMagic1]

How about if DVD-RB had it in one of the hidden areas with a warning about the use. I've done at least 10 conversions with dgpulldown that have been used on a number of different dvd players without a problem yet.

[hutch1711]

How about if DVD-RB had it in one of the hidden areas with a warning about the use.
Now you have my attention. Are you saying there is something in one of the hidden areas of DVD-RB that can be used when converting a pal source to ntsc?

[jptheripper]

not can, _could_, if jdobbs would write the code :)

[hutch1711]

not can, _could_, if jdobbs would write the code :)
Bummer.

BTW I ran with your suggestion and added lanczosResize(720,480) to my DVD-RB Filter Editor, then ran the prepare stage and encoded it using CCE 2.70 Trial. It would not resize the pal material! Tried again with CCE 2.50 with same result. Switched encoder to HC 0.15 Beta and it resized the pal material to 720x480 25fps no problem. :)

[jptheripper]

well thats good to know. i seem to remember having issues with cce, but i got it to work manually by generating a full d2v file with dgmpgenc (dgindex) and manually writing an avs file

[DMagic1]

Now you have my attention. Are you saying there is something in one of the hidden areas of DVD-RB that can be used when converting a pal source to ntsc?

Sorry about the confusion. I should have added a "?" at the end.
I was hoping that the PAL<>NTSC could be something added soon to RB.