Converting mp4 to mp3

I have a video I need to convert to mp3 (from the command line - not GUI): video.mp4

I tried:

ffmpeg -i -b 192 video.mp4 video.mp3

with no success. I get the following error:

WARNING: library configuration mismatch
Seems stream 0 codec frame rate differs from container frame rate: 59.83 (29917/500) -> 59.75 (239/4)
WARNING: The bitrate parameter is set too low. It takes bits/s as argument, not kbits/s
Encoder (codec id 86017) not found for output stream #0.0

so I tried lame:

lame -h -b 192 video.mp4 video.mp3

I get:

Warning: unsupported audio format

Am I missing something?

11 Answers

For FFmpeg with Constant Bitrate Encoding (CBR):

ffmpeg -i video.mp4 -vn \ -acodec libmp3lame -ac 2 -ab 160k -ar 48000 \ audio.mp3

or if you want to use Variable Bitrate Encoding (VBR):

ffmpeg -i video.mp4 -vn \ -acodec libmp3lame -ac 2 -qscale:a 4 -ar 48000 \ audio.mp3

The VBR example has a target bitrate of 165 Kbit/s with a bitrate range of 140...185.

soundconverter

is the leading audio file converter for the GNOME Desktop. It reads anything GStreamer can read (Ogg Vorbis, AAC, MP3, FLAC, WAV, AVI, MPEG, MOV, M4A, AC3, DTS, ALAC, MPC, Shorten, APE, SID, MOD, XM, S3M, etc...), and writes to WAV, FLAC, MP3, AAC, and Ogg Vorbis files, or use a GNOME Audio Profile.

SoundConverter aims to be simple to use, and very fast. Thanks to its multithreaded design, it will use as many cores as possible to speed up the conversion. It can also extract the audio from videos.

How to Convert MP4 to MP3 with VLC

Open VLC Media Player. Click "Media" > "Convert" to enter the "Open Media" window. Click the "Add" button on the right side of the screen to enter Windows Explorer. Locate the MP4 on your hard drive you want to convert. Click the "Convert" button at the bottom of the screen.
Select the name of the Target file.
Click the "Audio Codec" tab and select "MP3" from the "Codec" drop down box. Press the "Start" button to begin converting your MP4 to MP3 audio.
Click Start

I have a shell-script that uses mplayer (so it can convert anything mplayer can play) to extract the audio, and then encode it using lame. Here is the code:

#! /bin/bash
# any2mp3.sh
# Converts to mp3 anything mplayer can play
# Needs mplayer amd lame installed
[ $1 ] || { echo "Usage: $0 file1.wma file2.wma"; exit 1; }
for i in "$@"
do [ -f "$i" ] || { echo "File $i not found!"; exit 1; }
done
[ -f audiodump.wav ] && { echo "file audiodump.wav already exists" exit 1
}
for i in "$@"
do ext=`echo $i | sed 's/[^.]*\.\([a-zA-Z0-9]\+\)/\1/g'` j=`basename "$i" ".$ext"` j="$j.mp3" echo echo -n "Extracting audiodump.wav from $i... " mplayer -vo null -vc null -af resample=44100 -ao pcm:waveheader:fast \ "$i" >/dev/null 2>/dev/null || { echo "Problem extracting file $i" exit 1 } echo "done!" echo -n "Encoding to mp3... " lame -m s audiodump.wav -o "$j" >/dev/null 2>/dev/null echo "done!" echo "File written: $j"
done
# delete temporary dump file
rm -f audiodump.wav

First you need to apt-get install mplayer lame. After that, put the code in a file named ''any2mp3.sh'', give permission to execute, and put that in your $PATH, and you will be able to do:

$ any2mp3.sh file.mp4 another-file.wma yet-another.file.ogg

It will convert each file passed to an mp3 with the same name.

It's a little rough, but does the job.

I think the problem is with your syntax of the ffmpeg command.

ffmpeg -i source_filename -vn -ab 192k -acodec libmp3lame -ac 2 output_filename

should work.

I use this small script for converting m4a to mp3.

#!/bin/bash
for i in *.m4a; do avconv -i "$i" -vn -acodec libmp3lame -ac 2 -ab 160k -ar 48000 "`basename "$i" .m4a`.mp3"
done

To convert Upd_Sanity.mp4 to Upd_Sanity.mp3

$ sudo apt-get install ffmpeg && sudo apt-get install libavcodec-extra-53
$ ffmpeg -i Upd_Sanity.mp4 -vn -acodec libmp3lame -ac 2 -ab 160k -ar 48000 Upd_Sanity.mp3

OR (as ffmpeg is deprecated)

$ avconv -i Upd_Sanity.mp4 -vn -acodec libmp3lame -ac 2 -ab 160k -ar 48000 Upd_Sanity.mp3

Description

 -i input file name -vn disable video recording -acodec force audio codec to libmp3lame -ac set the number of audio channels -ar set the audio sampling frequency

If you need to use it frequently,

STEP 1 : Create a bash function that performs conversion

## utilities.sh
convertMP4toMP3(){
echo -n "Enter source mp4 file : "
read sourceFile
echo -n "Enter destination mp3 file : "
read destFile
avconv -i $sourceFile -vn -acodec libmp3lame -ac 2 -ab 160k -ar 48000 $destFile
}

STEP 2 : source that bash file

 $ source utilities.sh

STEP 3 : start conversion calling above function convertMP4toMP3

 $ convertMP4toMP3 Enter source mp4 file : Upd_Sanity.mp4 Enter destination mp3 file : UPd_sanity.mp3

References

utilities.sh

First, you have to understand a few things.

MP3 is an audio format.

MP4 is a video format.

To get the audio out of the MP4 (and to save it as an MP3), use soundconverter .

It is possible to use Lame directly if you use FFmpeg and pipe the output to lame (via stdout and stdin). An example:

ffmpeg -i video.mp4 -vn -f wav - | \ lame -V 3 - audio.mp3

This allows you to use lame's considerable commandline options if you wish to explore them...

you can try converting it by vlc or sound converter go to sound converter or find in your software center or use vlc for conversion open vlc media convert/save chose your file chose output format chose name and destination and start steaming thats all

Try Transmageddon is available trough the Ubuntu Software Center

Though it is GUI, you can use Audacity to control fixed or variable, as well as output quality, when doing MP4 to MP3 conversions.

Open Audacity, open the target MP4 file, click FILE, EXPORT, and then select output type (default is MP3) and click SAVE. It opens the MP4's audio channel(s), exports the MP3 audio to wherever (and whatever you save it as), and you are out of it (converting a 400-mb MP4 to MP3 on a 3Ghz AMD chip is around 10-minutes, with a 160kb/sec sample rate on the audio, and the audio file will be about half as large as the MP4).