Based on the sources of Quicktime4Linux, OpenQuicktime has since been extensively remodeled and streamlined. The build system is based on Automake/libtool and builds on most varieties of Unix. The codecs are all external from the main library. Included is a player, encoder, audio and video extractors, and a number of other utilities.
somaplayer is music player for MP3, Ogg, wav, audio CDs, MP3 streams, and Ogg streams. It is able to use the appropriate sound drivers or demons or to stream directly to an Icecast server (Icecast2 or SHOUTcast) or to encode in MP3 and Ogg Vorbis. It also acts as a sound daemon that is able to accept connections from other somaplayers or any other sound player (xmms, mpg123, and others) thanks to a special wrapper.
FMS is a tool to create all kinds of sounds from scratch. You can play any sound (sine, triangular, vowels, etc.) with any property settings (frequency, volume, balance, sweep, etc.) and modulations thereof. It also features tools to save sounds, play .MUS music, graphically display sounds, and make real noise.
XLV is a middle-level interface for Audio/Video (and generic multimedia format) playing, recording, and managing. The idea is that what you can do automatically (with one call) can also be done manually (all the decoding process can be extracted from the automate). XLV comes with a full bunch of plugins, including Vorbis, MPEG audio decoding, MPEG 1/2 video decoding, a Win32 codec interface, AVI decoder, Wave decoder, Quicktime decoder, MPEG/VOB (DVD file) decoder, and more functionalities like auto-format conversion, etc.