Ubuntu provides a useful tool called dir2ogg which makes it very easy to convert audio files from various formats to Ogg.
%apt-cache show dir2ogg
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Package: dir2ogg
dir2ogg converts MP3, M4A, WMA, FLAC, WAV files and Audio CDs to the
open-source OGG format.
.
It is a Python script that simply binds together the various decoders and
oggenc making it easier for the user to convert his/her music files. It also
supports ID3 tags.
As you can see, it can convert files from mp3, m4a, flac, wav format to ogg.
To install
%sudo aptitude install dir2ogg
To convert all the m4a files in a directory to ogg format, run the following command:
%dir2ogg -m -q 10 directory name
# -m flag is to convert m4a audio files in the directory.
# -q flag sets quality of the audio file (default is 3)
Useful flags:
%dir2ogg --help dir2ogg 0.11.8 (2009-08-04), converts audio files into ogg vorbis.Usage: dir2ogg [options] [arguments]Options: -r, --recursive convert files in all subdirectories of all directories specified as arguments -q N, --quality=N quality. N is a number from 1-10 (default 3.0) -t, --smart-mp3 try to use similar quality as original mp3 file (overwrites -q) -T N, --smart-mp3-correction=N decrease detected quality (implies -t) -n, --no-mp3 don't convert mp3s (use with '-d' or '-r') -a, --convert-all convert all supported formats -A, --convert-ape convert all APE files found in directories. -f, --convert-flac convert all FLAC files found in directories -m, --convert-m4a convert all M4A files found in directories -M, --convert-mpc convert all MPC files found in directories -w, --convert-wav convert all WAV files found in directories -W, --convert-wma convert all WMA files found in directories -V, --convert-wv convert all WV files found in directories --delete-input delete input files -v, --verbose verbose output