&audiocodec

Lets you specify the audio codec

Viewer-Side Option! (&view, &scene, &room, &solo)

Options

Example: &audiocodec=opus

Value	Description
opus	default; selects audio codec opus
red	selects audio codec red
pcmu	selects audio codec pcmu
pcma	selects audio codec pcma
isac	selects audio codec isac
g722	selects audio codec g722
pcm	selects audio codec pcm

Details

&audiocodec on the viewer side can let you specify the audio codec; opus (default), pcmu, pcma, isac, g722, red and pcm.

red

&audiocodec=red is pretty much like sending two opus streams, with one as a backup in case of packet loss; support in Chromium 97 and up, but the only way I can so far tell that it is working is to check if the audio bitrate has doubled.

When using &proaudio, &stereo, or higher than &audiobitrate=216 with this, the resulting bitrate may not actually double. I don't quite understand what's going on here, if its still working or not, so to be safe when using &proaudio or &stereo, along with &audiocodec=red, I set the bitrate to 216 by default, which will then result in a sending bitrate of around 440-kbps.

I've tried to enable RED-mode to work with PCM audio, but so far it will only work with OPUS audio.

pcm

&audiocodec=pcm now will support 48khz and 44.1khz mono playback (48khz default), and if &stereo is used, it changes to two-channel stereo 32khz.

The existing &samplerate=44100 option can lower the sample rate of this pcm mode (down to 8khz even), and hence the resulting audio bitrate. Since PCM is raw, &audiobitrate won't work, so expect 550 to 1200-kbps in just audio bitrates per viewer.

There may be clicking when using PCM mode (L16) if you are on a bad connection, as PCM doesn't have much in the way of error correction. You'll need to address this yourself probably with post-processing if any issue.

Future options

In the near future you'll be able to send PCM audio via &chunked mode, which will guarantees delivery of all packets sent, however there may be buffering issues if your connection can't keep up with bandwidth requirements.

Currently &chunked mode does work with OPUS-audio though; please provide feedback and requests if you use it. Chunked mode does not support WHIP/WHEP or Meshcast.

Related

page&codecpage&nofec