FFMPEG is the swiss army knife of Internet Streaming. As written in the homepage “is a very fast video and audio converter that can also grab from a live audio/video source. It can also convert between arbitrary sample rates and resize video on the fly with a high quality polyphase filter. “

Now, we are going to convert all FLAC files from a specific directory to MP3 256K.  It’s not a good idea from the quality perspective, but, you know, some players don’t support FLAC file.

First step is installing FFMPEG with all required codecs. If you are using a Debian base distro just run the following command:

# sudo apt-get install ffmpeg lame flac

unfortunately, ffmpeg is not part of Ubuntu 14.04 official repositories, so we need to add it before installing it:

# sudo apt-add-repository ppa:jon-severinsson/ffmpeg
# sudo apt-get update

Now from the source directory we can run something like that:

# (for FILE in *.flac ; do ffmpeg -i "$FILE" -f mp3 -ab 256000 "`basename "$FILE" .flac`.mp3" || break; done

this is only an example: ffmpeg can handle a lot of formats. To have a list:

# ffmpeg -formats

I suggest to read the official doc to go in deep