Vorbis is an open source, lossy audio codec project headed by the Xiph.Org Foundation and intended to serve as a replacement for MP3. It is most commonly used in conjunction with the Ogg container and is then called Ogg Vorbis.
Vorbis development began following a September 1998 letter from Fraunhofer Gesellschaft announcing plans to charge licensing fees for the MP3 audio format. Soon after, founder Christopher "Monty" Montgomery commenced work on the project and was assisted by a growing number of other developers.
They continued refining the source code until a stable version 1.0 of the codec was released on July 19, 2002. The latest official version is 1.1.2 released on 2005-11-28, but there are some fine-tuned forks available such as aoTuV. Source code (called libvorbis) for the Xiph.Org release is available from the official xiph.org download page.
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