Raw thoughts from Alex Dong

Convert mp3 files to ogg

I have never expected this to be hard. Sure it won’t be difficult to do this in 2013. But after sinking almost 1 hour into this, I decided to write it down hoping that it might save other people a bit time.

So I started with sox. I tried sox zit.mp3 zit.ogg and received an error message

sox FAIL formats: no handler for file extension `ogg’.

Then I tried dir2ogg -q7 zit.mp3 which was recommended by a post on Ubuntu’s discussion forum. But unfortunately, it still didn’t work out. Here is the error message I got:

dir2ogg 0.11.8 (2009-08-04), converts audio files into ogg vorbis.

WARNING: Mutagen failed on zit.mp3, no tags available Traceback (most recent call last): ID3NoHeaderError: ‘zit.mp3’ doesn’t start with an ID3 tag

INFO: Converting “zit.mp3” (using mpg123 as decoder)… [wav.c:143] error: cannot even write a single byte: Illegal seek [audio.c:630] error: failed to open audio device [mpg123.c:902] error: Failed to initialize output, goodbye. ERROR: Cannot open output file “zit.ogg”: Permission denied WARNING: No tags found… }}}

After much fiddling around, this is the final solution that was working for me. To chain mpg123 and oggenc together. mpg123 will generate a .wav file to the standard output, which oggenc takes in and emit a corresponding ogg file.

for i in *.mp3; do mpg321 $i -w - | oggenc -q7 -o ${i/mp3/ogg} -; done

A few caveats:

  • $i is the filename and ${i/mp3/ogg} changes the output filename.
  • -q7 select a level-7 sound quality. Since both mp3 and ogg are lossy sound format, converting one to another with the same sample rate would only decrease the sound quality. By specifying a higher bit rate, the ogg output would sound similar to the mp3 file.
  • The - are quite important.
  • On Ubuntu/Debian, you might need to install the packages using sudo apt-get install mpg321 vorbis-tools