Apple announced on Mac OS Forge today that they have open sourced their Lossless Audio Codec (ALAC). ALAC was introduced in 2004 as OS X’s core audio codec to compress audio files 40-60 percent without losing any quality. The codec is currently supported by Macs and the latest iOS devices.
ALAC was reversed engineered in 2005, but more and more applications could begin to adapt the codec now that it’s open sourced. Currently Plex, VLC, Boxee, and XBMC feature the codec, and there are sure more to come. ALAC has been open sourced under the Apache license.