Opus: a new, free, open audio codec that outperforms everything else


The IETF has finished its standardization effort for Opus, a new free/open audio codec that reportedly outperforms all other codecs on all axes. The codec was jointly created by IETF, Mozilla, Microsoft (through Skype), Xiph.Org (maintainers of Ogg), Octasic, Broadcom, and Google and Mozilla promises that a comparable video codec will come next.

One of the pernicious areas for free codecs is patents. The Opus FAQ says, "Opus is also covered by some patents, for which royalty-free usage rights are granted, under conditions that the authors believe are compatible with most (all?) open source licenses, including the GPL (v2 and v3)."

Unlike previous audio codecs, which have typically focused on a narrow set of applications (either voice or music, in a narrow range of bitrates, for either real-time or storage applications), Opus is highly flexible. It can adaptively switch among:

* Bitrates from 6 kb/s to 512 kb/s
* Voice and music
* Mono and stereo
* Narrowband (8 kHz) to Fullband (48 kHz)
* Frame sizes from 2.5 ms to 60 ms

Most importantly, it can adapt seamlessly within these operating points. Doing all of this with proprietary codecs would require at least six different codecs. Opus replaces all of them, with better quality.

It’s Opus, it rocks and now it’s an audio codec standard! (via /.)