My MP3 player needs MP3 files (hence the name).

The following snippets use gstreamer in a for loop.

Convert *.flac to *.mp3:
Original script here

for song in *.flac ; do gst-launch filesrc location="$song" ! flacdec ! audioconvert ! lame quality=2 mode=0 vbr=4 vbr-quality=2 ! xingmux ! id3v2mux ! filesink location="${song/.flac/.mp3}" ; done

Convert *.ogg to *.mp3:

for song in *.ogg ; do gst-launch filesrc location="$song" ! decodebin2 ! audioconvert ! lame quality=2 mode=0 vbr=4 vbr-quality=2 ! xingmux ! id3v2mux ! filesink location="${song/.ogg/.mp3}" ; done

Convert *.wav to *.mp3:

for song in *.wav ; do gst-launch filesrc location="$song" ! decodebin2 ! audioconvert ! lame quality=2 mode=0 vbr=4 vbr-quality=2 ! xingmux ! id3v2mux ! filesink location="${song/.wav/.mp3}" ; done

Required packages:
gstreamer-tools, gstreamer0.10-plugins-ugly