[MacDV] Re: MP3 Audio Extraction From MPEG Movie?

[Thubten Kunga]

Thanks Steven,
Filipe over at the Mac Pro Audio list gave me the answer. I knew you 
would want to know what it is. This is such an interesting set of 
posts, I'm including the entire chronology. I am so excited I performed 
my first Demux of an embedded MPEG1 Video and successfully extracted 
the MPEG1 Layer 2 audio track and then used iTunes to convert it to a 
96kbps MP3 file. And it was so damned easy. I didn't know what I was 
doing and yet I did it !! UNIX programmers are amazing. Thank GOD for 
Mac OS X and UNIX together at last.

k

On Friday, March 7, 2003, at 10:07  PM, Filipe M. wrote:

> I guess you may have gotten yourself a multiplexed (muxed) file. In 
> Quicktime Pro, press command-J and see what appears in the left 
> pop-up; you should have something like Movie and Muxed Track.
>
> If so, Quicktime will not demux the audio and video tracks apart.
>
> Under OS X, 
> http://www.versiontracker.com/moreinfo.fcgi?id=15987&db=mac might do 
> the trick for you...
>
> Hope I have helped,
>
> Filipe

On Friday, March 7, 2003, at 11:05  PM, Thubten Kunga replied:

Thanks Filipe,
It says MPEG1 Muxe...
Now I'll try your solution application if I can figure it out without 
any documentation. Oh there's a small read me file. Very complicated — 
NOT.  Ran the mpgtxwrap app from September aafter installing the 
package. How this miracle of UNIX programming can accomplish all this 
in a 161 K download is astonishing. Apple ought to have those kinds of 
UNIX programmers rewriting iMovie all over again from scratch.

OK. I have an mp3 file thanks to you Filipe. I installed the package 
and ran the Demuxer falwlessly. Took a minute max to Demux by simply 
choosing the MPEG Movie and pressing START. Displays percentage done in 
real time. Then I put the resulting MPEG 1 Layer 2 audio file in 
iTunes, Advanced—>Convert Selection to mp3 and a couple minutes later 
it resulted in a 96 kbps mp3 file in the Library. It's a miracle. This 
list rocks! Where else can you accomplish do it yourself Demuxing when 
you haven't a clue a half hour before you do it!

I love you Filipe! And every body else who's lurking too. Amazing. 
Simply Amazing!

I'm a born again Demuxer!!

the package you have to install prior to running the app is 140K
The app "mpegtxwrap" 1.1 is 356K

Here's the genius who wrote that tiny miraculous piece of code: 
mpegcut at biermann.org

I have to copy him this post. Thank you brilliant MPEG programmer whom 
ever you are.

k

On Friday, March 7, 2003, at 10:25  PM, Steven Rogers replied In BLUE:

> On Friday, March 7, 2003, at 9:02 PM, Thubten Kunga wrote original 
> Post In GREEN:
>
>> I'm stumped. I have downloaded a 55.4 MB 5:34 minute Music Video MPEG 
>> movie (i know not what flavor) that plays in QuickTime. But when I 
>> try to use my QuickTime Pro 6.1 to export the audio as an AIFF file, 
>> I get no option to do that. In fact no audio extraction option is 
>> shown.
>
> Right - MPEG audio is like a unfathomable enigma to Quicktime. It 
> plays, but if you do anything with the movie, the audio is history. 
> Most of the edit functions are disabled with MPEG.
>
>>  So I downloaded Extractor .95 from the internet and it won't 
>> recognize the MPEG movie as a file it can deal with. I did already 
>> export the original MPEG movie as a QuickTime Movie. But Extractor 
>> doesn't see that file either.
>
> Strange. I looked at the type and creator code of some MPEG files that 
> Extractor likes on my machine, and they're MPEG and TVOD. I think 
> Extractor expects MPEG-2 and your file might be MPEG-1 - that's one 
> guess.
>
>> I have a Judeth Stern and Robert Lettieri Visual QuickStart Guide to 
>> QT Pro 5 book that says that I am supposed to be able to see audio 
>> export options that don't show up in QTP 6.1. Did Apple remove the 
>> audio extraction options in 6.1 Pro?
>
> I don't think so. They're just absent for MPEG.
>
>> How do I get the audio out of the MPEG movie and ultimately into an 
>> MP3 file?
>
> Another option is BBdemux (I think its on Sourceforge) - I haven't 
> found it as reliable as Extractor, but its an option.
>
> Other programs like MediaPipe, FFmpegX, etc. should be able to extract 
> audio, but they're in the "dicey" category that Jim mentioned. It 
> seems to take boundless twiddling to get them to work. Audio is the 
> hitch when working with MPEG. I don't know enough about MPEG to know 
> the technical reasons behind it, but it seems like there aren't any 
> programs for dealing with MPEG as an integrated stream like other AV 
> formats. It seems standard procedure to "demux" them (i.e. split the 
> audio and video) and deal with them as separate entities. There are 
> more freeware programs for the PC - maybe the Mac will catch up.
>
> SR