Uncompressed audio data in CD quality consumes almost ten MB per minute. The MP3 procedure was developed by Fraunhofer IIS for the purpose of drastically compressing this data. Unfortunately, this procedure is patented. Therefore, companies that distribute MP3 encoders are required to pay license fees. The powerful MP3 encoder Lame was developed for Linux. Although the source code of Lame is under the GPL, we are not allowed to include this encoder in our distribution. For more information about the legal situation, visit the project web page at http://lame.sourceforge.net. In some countries (including Germany and the USA), the use of Lame is permitted for research purposes only.

Ogg Vorbis (vorbis-tools) is a free audio compression format that is now supported by the majority of audio players. The web page of the project is http://www.xiph.org/ogg/vorbis. The vorbis-tools package includes an encoder and a simple player. The encoder is started from the command line with oggenc. The only parameter needed is the WAV file to compress. The option -h displays an overview of the other parameters. The latest version of the Ogg encoder even supports encoding with a variable bit rate. In this way, an even higher degree of compression can be achieved. Instead of the bit rate, specify the desired quality with the parameter -q. The parameter -b determines the average bit rate. -m and -M can be used to specify the minimum and maximum bit rate.

ogg123 is a command-line Ogg player. The program requires the specification of a playback device. Start it with a command like ogg123 -d alsa09 mysong.ogg.