[pulseaudio-discuss] Virtual source (microphone)

[Grzegorz Kryza]

On Mon, 2010-01-18 at 17:53 +0100, Lennart Poettering wrote:
> On Mon, 18.01.10 16:36, Grzegorz Kryza (gkryza at gmail.com) wrote:
> 
> > > > This can be done using 'module-pipe-source' but it was recently removed
> > > > from Fedora packages so I'm looking for alternative.
> > > 
> > > This won't work, since that device does not really provide any kind of
> > > timing control, and also also depends on apps on the other side
> > > read/write data in the right speed. It's mostly a toy.
> > 
> > Yes, but if a timing is done by a process on other side of a pipe?
> > We have already implemented a solution based on pipe sink/source which
> > takes care about providing a data in correct sample rate, format, etc.
> > It works well on all Linux distros with PA we tested except Fedora
> > 12.
> 
> If you do that you need to make sure you provide an interface for the
> PA server to query the latency synchronously with the data
> transferred. Note that most video players schedule frames based on the
> audio clock, so if the latency estimation is not smooth and dependable
> video playback will be jumpy.

Thanks for interesting info.

However if a audio/video synchronization is not needed, for example
in case of virtual microphone? There are other drawbacks of using pipe
sink/source? Especially if it actually works in our case.


> module-pipe-sink/-source do not provide that.
> 
> Lennart
>