[pulseaudio-discuss] Virtual source (microphone)

[Lennart Poettering]

On Mon, 18.01.10 13:29, Grzegorz Kryza (gkryza at gmail.com) wrote:

> Hello.
> 
> I'm trying to figure out how to add a virtual source device.
> Virtual microphone available in all pulse enabled applications as a
> sound source. Voice data for this source should be provided by a third
> party application over a socket, pipe or any other inter process
> communication method.

You'd have to write module that lives in the PA process first for
that. We do not provide anything like that out-of-the-box since audio
should best not be passed onto many other processes. For latency
reasons you want to keep your pipelines short and every further
context switch comes at a price, espeically if you serialize things
onto a socket for that. Also notice that if you do implement this its
substantially more work than simply providing a fifo a la
module-pipe-source, since you need to implement proper timing control
which is usually the most complex part of a feature like this.

> 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.

Lennart

-- 
Lennart Poettering                        Red Hat, Inc.
lennart [at] poettering [dot] net
http://0pointer.net/lennart/           GnuPG 0x1A015CC4