LPCM to MP2 or AC3 conversion

[chocyman]

Ok folks..Im pretty new at this, so im probably gonna get a few things wrong!!:D

So I have a DVD with an LPCM audio track (A sporting event).
Ive read a few other posts on this subject of seeing if theres an "acceptable" way in reducing the size of the LPCM stream, as well, does it really need to be high quality if its crowds cheering and a load of sports fans shouting? Anyway..enough of my reasons.

Ive used DVD shrink for a while now, and been very happy. I ran DVD shrink twice over this file to compress it enough to fit on a DVD-R and burned it.
The video output has really suffered at the expense of a huge LPCM audio stream (which still sounds excellent as I believe the audio is uncompressed in DVD shrink??) , which really isnt what I want .As long as I can hear the commentators, the atmosphere and stuff, what do I care!!

So my question (as was the same one in this thread BTW http://forum.doom9.org/showthread.php?s=&threadid=68474) is...
* how do I rip the audio from the VOB files (ie do I use DVD2AVI >> to a WAV file or something??)
* Would I then run Besweet over the WAV file to get .AC3 or .MP2 (people opinions would be good on this :))and what settings to use in Besweet.... and finally...
* How do I then re-mux the sound with the existing video

From here Im guessing I could just run DVD shrink again over the new files and im thinking a smaller audio file should free up a bit more for a decent video.

I know its a fairly long(ish) help request, but after a few attempts with no joy, I d really appreciate any help people can give.
Surely others have needed to do this conversion process??

Any help or advice is really appreciated with this one.

Thanks

Chocs

[Wilbert]

You could use the following: "LPCM 24bit RAW streams to standard 24bit WAV files"

http://www.rarewares.org/others.html (second link)

[daphy]

if sound (2.0) is not that issue I would use MP2

example:

use a utility like smartripper, dvddecrypter... and demux the pcm track to a WAV file
then use besweet with its GUI choose WAV input to MP2 output

remux (author new dvd-> settings) this MP2 track with the MPV/MV2 (video)-track and the chaptors settings (optional) back with ifoedit

that´s it

CYA Daphy

[violao]

With 2.0 audio I normally use 192 kbps AC3 and the sound is great.

Also, if you intend to keep the existing IFO files, you'll need to adjust audio track settings in IFO with IfoEdit, as well as perform so-called "mock" strip - read about it in 2COOLs guides found in IfoEdit forum.

[daphy]

;)

the idea is ok if you got a good AC3 encoder, else MP2 is the easier way with the same/maybe better result :rolleyes:
as well as perform so-called "mock" strip - read about it in 2COOLs guides found in IfoEdit forum.

please give us a direct link - no time to search ;)

CYA Daphy

[chocyman]

Thanks heaps for the replies guys,:D

Ive had some semi success so far.

I ripped the audio to a WAV file using DVD2AVI, also demuxed to produce a .DV2 file
Using TMPGenc, fed the video (.DV2) and the raw WAV file to produce my files ready for re-authoring (probably gonna use TMPG dvd author), and then to burn back onto DVD.

One thing im unsure of tho. I ripped the audio track as one long WAV (ie all the VOB files, end to end). Some of these VOB files are menus (that have sound) and added extras. When I listen to the audio track, it is one long track (basically DVD2AVI has played all the VOB files in continuous form).
Im wondering if by doing this, the menus maybe all screwed and sound out of sync. Plus, and this is purely down to my lack of understanding, im pretty sure that as its re-muxing and encoding it will treat the menus as it would the main movie (ie no interaction or click to play stuff). Is this right? How would I re-create the menus to have the same functionality as before, but with a MP2 (or AC3 if I can find a decent encoder) soundtrack??

Im thinking that Id be best off ripping a WAV audio track for each VOB file, and encode => re-mux each seperate rather than one long track. Still...not quite sure about how a menu VOB differs from an ordinary (movie) VOB?? Anyone help or any good links to read???

Hope my ramblings make semi-sense anyway. I will look at ifoedit as well. Never used it, but its appeared a few times in a few articles Ive read and I figure that enough people rate it to be worth looking at!!

Anyway..thanks once again and if anyone can maybe point me in the right direction with regards to menus and my confusion above, then Id really appreciate it!!:p

chocs

[violao]

Originally posted by daphy
please give us a direct link - no time to search ;)

I suggest you read ALL 2COOL's GUIDES. (http://forum.doom9.org/showthread.php?s=&threadid=43142) For things related to modifying original VOB files (such as replacing cells/vobs, same things apply if you change audio/sub streams) read this one (http://forum.doom9.org/showthread.php?s=&threadid=60596). I was referring to step 14.

[violao]

Originally posted by chocyman
Im thinking that Id be best off ripping a WAV audio track for each VOB file, and encode => re-mux each seperate rather than one long track. Still...not quite sure about how a menu VOB differs from an ordinary (movie) VOB?? Anyone help or any good links to read???
[/B]

You can work on a single VOB file with DVD2AVI, just make sure that you remove all the rest in File->Open file list. BUT, you cannot work with individual VOB files if they are parts of a single titleset. You need to work on a complete titleset:

1. Open your first VOB file with DVD2AVI - that would be VTS_XX_1.VOB
2. Demux audio
4. Open ALL your titleset files with vstrip
5. Demux video (stream 0xE0)
4. Open VTS_XX_0.IFO with IfoEdit
5. Click on VTS_PGCITI/VTS_PGC_(whatever PGC is your movie)
6. Click on Tools->Save Celltimes to File
7. Encode audio to MP2 or AC3
8. Encode video if you want
9. Open IfoEdit (without any IFO file)
10. Click on DVD Author->Author New DVD
11. Imput new video and audio and CellTimes.txt
12. Choose destination dir and click OK. Wait few minutes.
13. Drag all files other than titleset VOBS to a new dir (overwriting newly created IFO files) and perform strip-streams-but-keep-everything (so-called mock strip) as per 2COOL's guides.
14. You'll have now completely new VOB and IFO files. Open any IFO in IfoEdit, click on GET VTS Sectors and you're done.

If you had subtitles and wanted to keep them, you could have demuxed them too and include them in step 11. I would use Vobsub for demuxing + SubToSup for creating IfoEdit compatible sup stream.

Better leave menu files alone, they probably don't use too much space. If you really need to perform the same operation on menus, you'll probably need to recreate them completely cause there's no simple way for remuxing audio while keepeng subpictures (buttons) commands intact.

Menu VOB is structurally the same as titleset VOB, except that vobs/cells in menu are not meant to be played continuously, so all cells normally pause at the end or loop to the beginning. Therefore, whatever you do to the menu, you need to perform on individual cells, so first you need to demux menu VOB on cells, demux cell content, recreate things, mux it back, join cells, etc. You must always keep track of vob_id/cell_id, cause that's what distingushes cells in dvd navigation (menu commands).

[chocyman]

Hey Violao..

Thanks man for the post(s)....really really helpful. As suspected, my last attempt resulted in one looonnnnnng movie, which included all the menus as 'part' of the movie, and no longer working (couldnt click on them)....
Anyway..am now in the process of demuxing the audio (taking a while) to WAV file(s) as seperate titlesets (when I selected VTS_01_1.VOB, it selects the others in that set..and so on and so on.Is that correct??)
I have one question...Ive never used vstrip before, but I think I understand it basically. Do I demux ALL the video streams (0xE0, 0xE1.......0xE7, video streams 0 to 7) at the same time (check all the boxes) or each one in turn?? Can you just briefly explain why I need to do this :rolleyes: sorry to be a pain!!!

Reading on, I should be able to follow the rest really well....really appreciate your help :p

Cheers

Chocs

[violao]

Originally posted by chocyman
(when I selected VTS_01_1.VOB, it selects the others in that set..and so on and so on.Is that correct??)
That's correct. You need all VOB files in a titleset selected to be able to work on a complete titleset. Same aplies to vstrip below.

Do I demux ALL the video streams (0xE0, 0xE1.......0xE7, video streams 0 to 7) at the same time (check all the boxes) or each one in turn??
Normally you would have only one video stream in a titleset - 0xe0 so you need only to demux that one. I suspect you use vstripGUI and that one is not aware of actually included streams, so it lists all possible stream IDs. If you are not sure about ID you can check with DOS vstrip. You'll also be able to see this info with IfoEdit by opening corresponding titleset IFO file and looking under root level Video attributes.

[chocyman]

Hey violao

Apologies for not replying sooner....my computer decided to go tits up and crash...format and re-install job im afraid!!! Anyway...Ive printed off your advice and going to have another crack at it. See how I go :p

Anyway...wanted to say big thanks for the help. Fingers crossed it should all work!!

Cheers

Chocs

[chocyman]

Hey folks..

Just thought Id share with you a neat little way of doing this...found this by accident whilst playing around with TMPGenc DVD author the other day.
So..to convert a LPCM track to a MP2 (saves allllooottt of space).
Firstly rip the movie off the DVD (I used smart ripper)
Secondly, fire up TMPGenc, add DVD video, and get to the screen that gives you the option of re-encoding the audio as an MP2 or the original PCM audio track.
Thirdly..click go..
So...the output of this will still be a large file, but encoded with a MP2 track rather than a LPCM
I then ran DVDShrink over the file (which compresses the video, but not the audio), and hey presto..onto a DVD, all menus, nothing changed, except for the audio track.
Downside is that you cant encode other audio streams (AC3 etc etc), and you do only get a stereo output, but its an easy way to do it.
Thanks guys for all your help!!

Cheers

Chocs