Opus

File Format
Name	Opus
Ontology	Electronic File Formats Audio and Music Opus
Extension(s)	.opus

Description

Opus is a lossy audio compression format designed by the Internet Engineering Task Force (IETF) for applications requiring high-quality, low-delay audio transmission (e.g. telephony or network music performance). It incorporates technology from Skype's SILK codec and Xiph.org's CELT codec.

Information

• RFC 6716 - Definition of the Opus Audio Codec
• Ogg Encapsulation for the Opus Audio Codec (draft-ietf-codec-oggopus-00)
• RTP Payload Format for Opus Speech and Audio Codec (draft-spittka-payload-rtp-opus-03)
• Opus, the Swiss Army Knife of Audio Codecs (Presentation at linux.conf.au 2012]

Software

The Opus Codec downloads page contains opus-tools (encode / inspect / decode) .opus files and opusfile, an API for developers.

foobar2000 can play back and encode Opus files (with the Free Encoder Pack

Links

• Bitstream conformance set
• The .opus test set (including intentionally malformed files)

See Also

• CELT
• SILK