Opus Audio Codec

Dev Community Dev/API Corner
1

Hello Plex Team,

 

The Opus Codec could be very interesting for you.

The codec comparison between AAC and Opus looks very good.

 

Source: opus-codec.org

<em>Overview</em>

Opus is a totally open, royalty-free, highly versatile audio codec. Opus is unmatched for interactive speech and music transmission over the Internet, but is also intended for storage and streaming applications. It is standardized by the Internet Engineering Task Force (IETF) as RFC 6716 which incorporated technology from Skype's SILK codec and Xiph.Org's CELT codec.

<em>Technology</em>

Opus can handle a wide range of audio applications, including Voice over IP, videoconferencing, in-game chat, and even remote live music performances. It can scale from low bit-rate narrowband speech to very high quality stereo music. Supported features are:

  • 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 fullband
  • 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

 

regards

 

2

Plex Media Server relies on FFMPEG for audio-video decoding/transcoding. Any requests for added codec-support should be directed there.

3

Opus decode and encode is in FFMPEG (using libopus) from version 1.1 forwards.

When will Plex add libopus to Clients/Server and allow the transcoder to use it?

For Plex/Web Opus support was added to Firefox 15+ and Chrome 27+ (dev) so HTML5 playback should work with little extra work.

It's also now the IETF standard for web audio and will be supported by Safari in the next release.

4

Since this discussion is not specific to channel development, I'm moving it to the general development forum.

5

This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.