Receiving two audio streams with RTP

[krusty]

Hello all,

I would like to know if it is possible to listen to two simultaneous audio streams via RTP. It seems to be possible, but I can't make it work.

I tried to do that in the two following ways:

Via VLC User Interface:
- went to "Media" -> "Advanced Open File" -> "Network" and entered the first stream address.
- then went to "show more options" -> "Play another media synchronously" and entered the second stream address.

and via SDP file:
v=0
o=root 282212517 282212517 IN IP4 127.0.0.1
s=music.sdp
c=IN IP4 127.0.0.1
t=0 0
m=audio 8000 RTP/AVP 0
a=rtpmap:0 PCMU/8000
m=audio 8002 RTP/AVP 0
a=rtpmap:0 PCMU/8000

In both cases VLC shows me (in the "Media Information ..." window) that I have two streams, but it only plays the first one. Am I missing something or does VLC not support this feature?

thanks,
ps: using VLC 0.9.8a

[Rémi Denis-Courmont]

You can select which audio track to play from the audio track menu.

[krusty]

Thanks for your answer.

This is a nice feature that I didn't know. But I would like to MIX both streams and couldn't figure out how to do that. Is that possible?

[Jean-Baptiste Kempf]

Thanks for your answer.

This is a nice feature that I didn't know. But I would like to MIX both streams and couldn't figure out how to do that. Is that possible?

No.

[Rémi Denis-Courmont]

If you want to mix, you should open two separate streams, and let the OS do the job.

[krusty]

Hello,

Thanks again for your answers.

That is what I'm doing now, letting the OS mix them. However, this is not a very nice solution because I have to sync both audio streams, and to do that I have to send both streams and start both VLCs at the same time. Unfortunately, several things can delay one of the streams and desynchronize them.

I was expecting that VLC could sync them through RTCP packets, sent along with the streams. I'm looking forward to this feature in future releases.

Thanks,