Opus Interactive is a free audio codec made especially suitable for interactive real-time applications, interactive speech and music transmission over the Internet, but also intended for storage and streaming applications like teleconferencing, in-game chatting, and even live, distributed music performances

In the past we had MP3 for music, SILK for VoiP, etc. Now this Opus Interactive Audio Codec it is standardized by the Internet Engineering Task Force (IETF) as RFC 6716, promising better quality and lower costs reducing the downloaded bytes being a light format.


  • Bit-rates from 6 kb/s to 510 kb/s
  • Sampling rates from 8 kHz (narrowband) to 48 kHz (fullband)
  • Frame sizes from 2.5 ms to 60 ms
  • Support for both constant bit-rate (CBR) and variable bit-rate (VBR)
  • Audio bandwidth from narrowband to full-band
  • Support for speech and music
  • Support for mono and stereo
  • Support for up to 255 channels (multistream frames)
  • Dynamically adjustable bitrate, audio bandwidth, and frame size
  • Good loss robustness and packet loss concealment (PLC)
  • Floating point and fixed-point implementation

Although Opus is just out, it is already supported in many applications, such as Firefox, GStreamer, FFMpeg, foobar2000, K-Lite Codec Pack, and lavfilters, with upcoming support in VLC, rockbox and Mumble.

Most importantly, this is a really open source codec which gives us the possibility of great updates and the assurance of having more programs with all its features.

Wiki Info:

Official Website: http://www.opus-codec.org/

Informal development chat and support #opus on irc.freenode.net (You can join the chat room through the web interface if you don’t have an irc client.)