How to (freely,safely) convert MP4 video to MP3 audio on WinXP?

April 2, 2010 6:10 PM

My Flip video cam exports a clip as MP4 video. I just want the audio (as an MP3). I don't want to install software from potentially untrustworthy sites on my (WinXP) PC, or to pay. Suggestions on how to convert it?

(I've been beating my head against the keyboard on this, and it - and I - am sore)

posted by ahaynes to Computers & Internet (13 answers total)

Alas, I don't think that Audacity grasps the concept of a video MP4; it *does* accept the file, but when I play it (from w/in Audacity), or export it as MP3, ye gods...it's cat repellant.
posted by ahaynes at 6:34 PM on April 2, 2010

No idea if this will work, as I'd use Quicktime Pro on the Mac to do it, but this page lists something promising:

http://www.afterdawn.com/guides/archive/how_to_edit_aac_mp4_audio_page_2.cfm
posted by tomierna at 6:40 PM on April 2, 2010

[VLC](http://www.videolan.org/) will do it. Open it, hit File->Convert/Save. Add in your file, and punch in these settings:

* Enscapulation: MPEG 1

* Video: (uncheck)

* Audio: switch Codec to MP3, use desired bitrate.

Fill in the Destination, save as filename.mp3. Hit Start. Done.
posted by ConstantineXVI at 6:54 PM on April 2, 2010

Er, wrong forum. Here's the VLC link
posted by ConstantineXVI at 6:55 PM on April 2, 2010

www.zamzar.com has worked for me before.
posted by Potomac Avenue at 7:31 PM on April 2, 2010

2nding zamzar.com. You give it the file, and then tell it what formats you want to download - i.e., audio only in mp3. It's so ridiculously helpful!
posted by niles at 9:36 PM on April 2, 2010

Alas.
Zamzar has a 100MB limit (for free), which my ~5 minute video exceeds.
And I regret to say that Videolan hasn't done the trick either - with the MPEG1 encapsulation I got more cat repellant, & without it I got lip-smacking noises on top of the audio. Perhaps I should be desiring a different bitrate (default is 128 kb/s), or sample rate, or something... Or it's possible that Flip just doesn't do MP4 right.
More likely it's my karma though.

But I appreciate your answers, & hope they'll help others.
posted by ahaynes at 10:09 PM on April 2, 2010

(and re tomierna's suggestion, in reading the documentation at the afterdawn.com URL, I couldn't see how to end up with MP3 format)
posted by ahaynes at 10:23 PM on April 2, 2010

Use Avidemux: http://avidemux.org/admWiki/index.php?title=Save_only_audio
posted by cowmix at 10:45 PM on April 2, 2010

I don't know why nobody has suggested WinFF for this. All of these other tools are for various sorts of editing; WinFF was made for conversion, and has all the options you'll need. It works better than all of these other options too, in my experience.
posted by koeselitz at 11:26 PM on April 2, 2010

(You might figure this out yourself, but: before you convert, click over to "Audio" on the presets down below and enter "320" for the bitrate. That'll give you the best possible bitrate.)
posted by koeselitz at 11:33 PM on April 2, 2010

ffmpeg -i video.mp4 -vn -ac 1 audio.mp3
posted by wongcorgi at 7:26 AM on April 3, 2010

(Yeah, ffmpeg works brilliantly too - In fact, WinFF is just a GUI front-end for ffmpeg, which runs from the command line. You can just try ffmpeg if you're comfortable with the command line, but I've found WinFF really helps make things easier a lot of times, especially with batch transcoding.)
posted by koeselitz at 9:24 AM on April 3, 2010