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OGG Vorbis File Format.
Ogg vorbis format developed by Xiphophorus http://www.xiph.org/. On this website you can find the source code of the project. It is part of the Ogg, providing a fully open multimedia systems. The name of the format (Vorbis) comes from the name of the hero of the book Terry Pratchett, "Small Gods".
The sound quality is encoded in the Ogg format, is somewhere between MP3 and AAC.
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