demux/extract soundtrack from avi [Archive]

sibe

18th December 2001, 14:21

Nandub definitely does it! Select "Direct stream copy" in the audio menu, then choose "Save WAV" in the file menu and then rename your file to .ac3

I've seen a lot of people getting confused about this, although it says save WAV it actually extracts the audio track in whatever format it is when you checked "Direct stream copy". It will have a .wav ending but you just have to rename it and you're fine.

Sibe

ChristianHJW

18th December 2001, 17:56

.. sibe is correct, this is the way to do it. If you chose ' "audio.ac3" ' as your filename you may even do the renaming process while its demuxed ...

Stendrik

21st December 2001, 15:53

I have made a DivX movie with AC3 sound and then splitted it into two parts.
Now I want to extract the AC3-files from these DivX-files again(doesn't sound logical, I know).
Can anyone tell me how to do this ?:( :(

sibe

22nd December 2001, 18:19

The same question was already answered in this forum. Look at that thread: http://rilanparty.com/vbb/showthread.php?s=&threadid=11514

Chaos_rox

24th February 2002, 01:59

Aiight, so,just like the topic, i need some help extracting AC3 audio from a divx (.avi) file. (i was surprised to, a divx with ac3 audio!?) Anybody have any ideas on what to do? :confused:

dragoman

24th February 2002, 09:23

Use Virtualdub.

First, load your avi file under the "file" menu.

Go to the audio menu, select both "avi audio" and "direct stream copy".

Then go to file menu, select "Save wav". Ignore the title, and name the file xxxx.ac3

Then click okay.

The program will demux the audio as-is, that is it will extract the ac3 file from the divx to you hard drive.

BTW, I always encode my DivX movies with the ac3 audio from the dvd. Plays back much cleaner, crisper, and surround sound is built in.

dragoman

Slogra

23rd March 2002, 14:07

I want to re-encode a movie, but i don't want to re-encode the audio. So i want to get the mp3 from the old movie and put it in the new one.

How do i get the mp3 directly from the old avi?

I know this qeustion has been asked before, but i don't remeber the solution. :rolleyes:

THANKS!

DSPguru

23rd March 2002, 14:11

read the AUDIO FAQ.

Slogra

23rd March 2002, 14:52

Ok, the audio faq didn't really help me much.

But i think i figured it out myself.
I saved the sound to .wav with Nandub. I always thought this would give me a uncompressed wav file, but it's an mp3 with a wav header instead.
I guess i can use this wav file for the new video. Should i import it as .wav or as .mp3 file in Nadub?

DSPguru

23rd March 2002, 14:58

Originally posted by Slogra
Ok, the audio faq didn't really help me much.

don't you think that this could have HELPED YOU ?15) How can I extract an AC3 stream from an AVI file with AC3 audio?

This is easy with Nandub.
audio -> direct stream copy
file -> save WAV
rename the resulting file from xxx.wav to xxx.ac3

make sure this is your LAST post regarding issues that had been discussed in the past or appears in the FAQs.
doom9 decided to make sure all users obey the forum rules (http://forum.doom9.org/forum-rules.htm), and he'll start banning users that don't !

we won't tolerate lazy users.

Slogra

23rd March 2002, 15:30

Mp3 is not the same as Ac3. So i didn't read this part of the faq.

Sorry...

gregor7777

27th March 2002, 00:28

No reason to be so snooty DSPguru, he has a valid point. It doesn't say MP3, so why would one assume that the same process would work? Especially if he didn't know that the process had anything to do with wav's?

Sheesh, I don't think Doom9 had this in mind, the guy was being cool.

I just did a quick search as I had the very same question, I didn't really come up with much until I read this thread.

Now, on to another Q: Is this just a shortcoming of the program? I mean, if the file still consists of a VBR MP3, why does it make a difference what the header says it is? Just curious...

MaTTeR

27th March 2002, 00:49

DSPguru snooty? Nah..he's just enforcing the rules. Yes, Doom9 does have this very thing in mind. Were looking for quality posts which indicate people are reading the documents and exploring a little before posting.

The problem is that were seeing to many people that are afraid to point and click a button if the docs/FAQ's don't say to do so exactly down to the letter. Hope this makes sense.

gregor7777

27th March 2002, 01:07

@Matter

I understand, and you were clear enough. I know what you mean, as I'm a long standing members at other various tech boards that face the very same problem.

Anyhow, I just thought that DSP was a little curt, where he might not have to have been. I mean the guy did post the resoloution to his own problem, instead of disappearing into nowhere, you know? But you fellows have the way of it, so I'll digress.

Thanks

LigH

27th March 2002, 10:27

Dear DSPguru,

if you rant about lazy users, you shall also rant about lazy guides: In fact, it might work to extract the audio to a WAV file, but the resulting file will always have a RIFF-WAVE header when using Nandub/VirtualDub. Therefore, simply renaming the file is indeed wrong. Although it may work in some cases, e.g. many AC3 or MP3 reading applications may ignore the headers and skip to the first valid block; instead, others may not and will fail - due to the additional WAVE header.

For example, the WinDAC (http://www.windac.de) archive (currently wdac153.zip) contains a tool which can strip the header off a wave file (StripHdr.exe); such a tool shall be used to get raw compressed data in a clean way out of a compressed wave file. I wonder if it is allowed to distribute it separately; if not, it may not be a hard job to implement such a tool, even with a GUI. All it needs is 1) finding the "data" chunk, 2) extracting the data to a new file - simply removing 44 bytes would not be the correct way, though - compressed waves have at least an additional "fact" chunk and may contain even more chunks, which all do not belong to the compressed audio data.

DSPguru

27th March 2002, 11:07

LigH,
any decent ac3/mp3 decoder has a sync engine in order to handle corrupted streams. i implemented such a synchronizer in BeSweet, and most of the programs will usually skip the wav header very easily.

there are tons of Header removers out there. i recall that phillips' pub_enc package includes a format convertor that does -> wav2pcm.

jokklas

15th May 2002, 19:08

Hi, anyone have a clue as to how I can extract the AC3 from a DivX? VirtualDub/NanDub doesn't seem to be able to simply save it from the DivX. When I tried it sounded.. hmm.. weird as hell kinnda.

Thanks in advance / jokklas.

DSPguru

15th May 2002, 19:09

read the audio faqs and post your logfile.

landok

21st July 2002, 18:19

I 've try with VirtualDub and NunDub and the result is a wav file.
When i rename the wav to ac3 and try to play it with a dvd player (powerdvd) it takes out this message "Unknown file format".
But everything goes ok if i try to play a ripped ac3 from a dvd.

Please anyone an idea?

:(

DSPguru

21st July 2002, 18:25

:readfaq: q15.

landok

21st July 2002, 19:01

Thanks DSPguru for your answer!!!!!!!

:p

katarakt

27th July 2002, 01:16

the movie is a divx movie with mp3 audio stream and i want to transcode it to a vcd. I need to extract the audio for later muxing with the new video-stream.
How can i extract the mp3 audio from the avi?

DSPguru

27th July 2002, 05:59

:readfaq:

katarakt

27th July 2002, 19:20

i've checked the faq but first found nothing, now with the second try i found one method with virtual dub...testing...sorry for my mistake :(

wschindel

31st July 2002, 14:02

I'm trying to convert a DivX file to VCD. I'm using Virtual Dub to extract the wav file to use as a source in TmpgEnc. When I try to save a Wav, the following messages appears:
1- ACM faild to suggest audio decompression format.
2- AVI output WAV: invalid identifier

Can someone help me?:(

DJ Bobo

31st July 2002, 17:24

Use AVI2WAV or NanDub (File -> SAve WAV)
and look into the audio FAQ -.-

benafk

24th August 2002, 05:26

I have been trying to get my digital out to work and have read Matter's extremely informative post on AC3. I have found that my interleave settings are the problem.

I have a large number of AVI's with AC3 interleaved at the incorrect rate. I want to "rip" the AC3 and re-interleave at the correct rate but cannot seem to figure out how rip the AC3 using Nandub.

I really appreciate any help you can give.

Fox Mulder

24th August 2002, 09:56

http://forum.doom9.org/showthread.php?s=&threadid=7633

Duplex

30th August 2002, 03:24

I tried to do it in Nandub/VirtualDub with "File/Save WAV" while Audio was set to "Direct Stream Copy", but it gives me a WAV anyway.

I dont no any other way, so i ask you guys....

Thx + greets

Duplex

sillKotscha

30th August 2002, 04:32

save as .mp3 - but keep in mind that wav-headers are still included.

try the search button to find out about BeSplit

cheers Sill

pacohaas

30th August 2002, 06:07

:readfaq:

ArcticFox

6th September 2002, 09:41

ive got an avi movie, with 5 channel ac3 audio, now i was wondering how i could demultiplex tha ac3 without comprimising its quality or re-encoding it as i would like to be able to convert the avi to mpeg2 for dvd authoring,

i tried using nandub to "save wav as.." then renamed it to ac3, but when i dropped it into my dvd authoring software it gabe me an error

dionisos

6th September 2002, 15:53

i've almost the same problem as ArticFox

i muxed the 5.1 ac3 with the avi with th default interleaving (i think the delay doesnt matter here) and, when i tried to demux it, the ac3 becames "choppy" like "Blablabla "ta-ta-ta-" blablabla "ta-ta-ta"" u know... :)
it was like a mp3 extracted from a scratched CD

i dont have a clue about whats causing that
=\

thanks!!!

[]s

yuk0

7th September 2002, 00:08

i have this movie its in ac3 audio format so i cant use it with tmp genc is there anyway to extract the ac3 audio from the divx file then convert it to .wav?

Palikrovol

7th September 2002, 03:11

Take a look to q15 in faq, maybe you find the solution.

sherpya

7th September 2002, 04:16

Look at this thread for the pics:
http://forum.doom9.it/viewtopic.php?t=157

This is the italian forum so I will translate in english but I don't want to reupload images

- Open Graphedit
Insert "File Source (aync)" and select the avi
Insert an "Avi Splitter" and connect with File Source
Insert an "Avi Mux" and connect to first pin (Stream 00) of Avi Splitter
Insert Null Render (or file writer if you want also the video) and connect to Avi Mux

The Insert a "Dump" filter (FileWriter wont work here) and connect with second pin (Stream 01) of Avi Splitter
(Dump filter is into audiofilters pack - download section)

Press Play.
Pregress bar will stop after few seconds, no need to wait the entire duration (this happens when avi splitter is connected with a null render without avi muxer)

This apply to:
avi -> avi (only video) + mp3
avi -> avi (only video)
avi -> mp3
and also
avi -> avi (only video) + ac3
avi -> avi (only video)
avi -> ac3

just adding null renderer
I've tested all solutions except avi->avi (only video) but
this case easy works on virtualdub
Hope this work
Cheers Sherpya

mustaneekeri

18th September 2002, 11:52

Well i wasn't sure which forum i should post this but here it goes.
I have AVI clip, (Microsoft High-Speed MPEG-4 V2 video and MP3 audio)
of which i want to demux the MP3 stream. How im goin to do this? With Graphedit? Which filters i should add in graph?

DJ Bobo

18th September 2002, 14:09

Man, you have 121 posts and ask something like this??
Havn't you seen the FAQs??????

Fast answer: use AVI2WAV

mustaneekeri

20th September 2002, 00:36

Originally posted by DJ Bobo
Man, you have 121 posts and ask something like this??
Havn't you seen the FAQs??????

Fast answer: use AVI2WAV

hmm, it's just i've newer had to do such a thing. Ther's always a first time.

goldirin

17th November 2002, 15:22

I have many video files in AVI forma with AC3 soynd 5.1
How I can demuxe the AC3?
I use the nandub save option and the stream has a wave header.

pacohaas

19th November 2002, 17:54

:readfaq:

janosch

19th November 2002, 20:10

Originally posted by dionisos
i've almost the same problem as ArticFox
i muxed the 5.1 ac3 with the avi with th default interleaving (i think the delay doesnt matter here) and, when i tried to demux it, the ac3 becames "choppy" like "Blablabla "ta-ta-ta-" blablabla "ta-ta-ta"" u know... :)
[]s

use 60/80 or 80/80 and ms not frames.

CU

MaTTeR

19th November 2002, 22:23

IMHO using NanDub to mux AC3 is a bad idea since we now have an alternative that does it properly and the results are impressive. Why not use AVImux? It also has some demuxing capabilities.

janosch

19th November 2002, 23:40

why not, if it works !
Nandub works god for me.

Cu

MaTTeR

20th November 2002, 00:01

Look around the forum and you'll see plenty of people posting the same ol problems(ie. choppy playback, dropped signals, etc.). If you don't use SPDIF then that explains why you ask me such a thing;)

Mux your movie with AVImux and then do it with NanDub, compare the playback of each. Also, watch carefully the number of times your CD gets accessed then you'll answer your own question.