I came across some .ape files the other day. Apparently, they're a lossless format like flac. And the name? MonkeyAudio. Get it? Because the extension is .ape.
Licensing apparently isn't full-on open-source kosher, but there are a couple of utilities you can use if you need to convert the for an audio play that doesn't handle .ape.
Option 1: via the command line, install this package
sudo apt-get install flac libjmac-java lame mp3splt
run like this:
lossless2mp3 START_DIRECTORY
(The author intends to add more options in the future.
View the helpfile for lossless2mp3 to see what they currently are.)
Option 2: use SoundConverter. Download and install via your package manager software.
Currently more than a couple hundred people have posted good reviews on it.
