Efficient tools to build your streaming infrastructure


Talkback for Larix Broadcaster

Get audio return feed on your streaming mobile device

Larix Broadcaster is widely used for streaming from mobile devices, opening new opportunities for content generation. However our users were missing the ability to give audio feedback to the operator.

Interruptible foldback (IFB) return feed has been known in live production professional tools for decades.
Now Larix Broadcaster can also receive input streams to play audio return feed, this brings new use cases:

  • Studio can now talk to a talent while the stream is online.
  • Stream director from studio can ask operator to perform some actions to improve the layout.
  • In multi-camera setup, operators can be notified when their particular streams are exposed to the audience.

The feedback stream can be generated by any streaming tool, server or service that supports required protocols.

Talkback is part of Larix Premium in-app subscription avialable for just $9.99/m.

Talkback input

Larix Broadcaster Talkback uses Larix Player connectivity engine to obtain and play the audio. So it provides these input options:

  • SRT Pull: your source provides feedback via SRT Listen interface.
  • SRT Listen: your source will use SRT Push to deliver feedback to streaming device.
  • SRT Rendezvous: your source and streaming device will connect via Rendezvous and source will produce the stream.
  • SLDP: your source provides public stream via Softvelum low latency protocol with minimum delay.
  • RTMP: your source provides public RTMP stream which is pulled by Larix.
  • Icecast: you may even use your online radio tools to produce the audio feedback.

AAC audio codec is supported for all talkback input.
Opus audio codec is supported for SRT and SLDP input.

Larix Broadcaster setup is easy.

  • Open application settings and choose Talkback.
  • Add one or more incoming talkback source connections.
  • Select one source which you want to receive.
  • Larix will be trying to connect to the stream and once it's available, the audio will be played.

We recommend using headphones to play the inbound stream to avoid echo in your output.
On iOS, change "Audio" -> "Volume keys" setting to "Do nothing". Connecting/disconnecting headphones caused volume change, and it may trigger start/stop broadcast.

Take a look at these video demos of Talkback usage:

This sneak preview demonstrates Talkback setup via SRT Listen.
Later on we'll release a video tutorial with full talkback setup example, subscribe to Softvelum YouTube channel to get it once it's ready.

Flexible output

Getting audio feedback is a great addition for full set of Larix Broadcaster connectivity features:

  • SRT in Push (Caller), Listen and Rendezvous modes via libsrt version 1.5.0.
  • RTMP and RTSP publishing, with SSL support for RTMPS/RTSPS.
  • RIST protocol Push (Caller) mode support via librist version 0.2.7.
  • Pausing the stream and audio-only capture mode.
  • Multiple simultaneous connections to several destinations, with specific authentication methods for all popular services and servers.

Look at all the features of Larix for Android and Larix for iOS .
To learn more about Larix streaming setup and usage, visit docs reference.

Try Larix Broadcaster in action

Download at App Store
Get it on Google Play