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Low Latency Audio over Internet

Posted: Thu Jan 10, 2019 3:21 pm
by Opusss
So here's my project. I want to build a transmit/receive system (pair of RPi's) that would handle a low-latency (less than 10ms would by ideal) audio transmission over the Internet.
I know there is latency that is uncontrollable (network hops, switches, DNS servers, etc, etc. .. ) but from my research, they add very little delay, and it would be less than considerable.
Ideally, I'd have an audio-in and an audio-out port on each RPi.... along with a connection "procedure" to connect both RPi's together ... I would prefer not using a server based system, again to reduce latency... peer-to-peer would be needed.

So basically, does anyone know if a similar project has been worked on ?
There are tons of other projects that handle audio transmission over the Internet, but they take very little consideration of the latency.
Latency is very important for this project, as I would like to have both units to output/input practically at the same time.
Any ideas would be much appreciated !

Re: Low Latency Audio over Internet

Posted: Fri Jan 11, 2019 2:18 pm
by RpiName
Over internet? UV4L + Janus can do the job:
rpi1 <--> Janus Geteway <-->rp2
with imperceptible latency.

More info at https://linux-projects.org

Re: Low Latency Audio over Internet

Posted: Fri Jan 11, 2019 3:07 pm
by Opusss
Thanks ! Will give it a try for sure !
I'm a little concerned since it's video based, and I've read that disabling video is not possible.
It could inject unwanted delay in transmission ...
but, hey, can't see until I try !

Re: Low Latency Audio over Internet

Posted: Fri Jan 11, 2019 3:28 pm
by Andyroo
Try this post viewtopic.php?f=38&t=230942

Yes - I am the one questioning it for my needs :)

Re: Low Latency Audio over Internet

Posted: Fri Jan 11, 2019 3:36 pm
by Opusss
Cool ! Very interesting ! Thanks !

Re: Low Latency Audio over Internet

Posted: Fri Jan 11, 2019 3:41 pm
by RpiName
Opusss wrote:
Fri Jan 11, 2019 3:07 pm
Thanks ! Will give it a try for sure !
I'm a little concerned since it's video based, and I've read that disabling video is not possible.
It could inject unwanted delay in transmission ...
but, hey, can't see until I try !
A video driver like the uv4l-dummy driver has to be specified but does not have to be used. In facts you can disable video (both send & receive). See the uv4l-server manual option.

Re: Low Latency Audio over Internet

Posted: Fri Jan 11, 2019 3:44 pm
by Opusss
RpiName wrote:
Fri Jan 11, 2019 3:41 pm

A video driver like the uv4l-dummy driver has to be specified but does not have to be used. In facts you can disable video (both send & receive). See the uv4l-server manual option.
This gets interesting by the minute !! Thanks !