Ogg Vorbis is a high-quality lossy audio codec that is free of intellectual
property restrictions. libvorbis is the main vorbis codec library. It depends
on libogg for bitstream and framing support.
Information regarding Project Releases and Project Resources. Note that the information here is a quote from Freecode.com page, and the downloads themselves may not be hosted on OSDN.
This release adds numerous fixes and optimizations plus three new
features: a Timebase conversion call to libvorbis, ov_crosslap() which
allows smooth transitions between two vorbis segments, and ov_halfrate()
which allows a "free" conversion from the source sample rate to half of
the source rate.