[pulseaudio-discuss] what's the minimum requirement for a PA sink module

[Maarten Bosmans]

2011/12/1 wang dengyi <dy_wang at yahoo.com>:
> Hi Guys,
>
> We use pulseaudio as the audio server on our Linux system but the real sound
> card is on the other OS which only provides a very basic audio driver. The
> audio driver only receive the PCM data (in certain format) and play it back.

Could you explain your setup a bit clearer? Do you want to run pulse
on Linux or some other OS? Is there an ALSA or OSS driver available or
is this a network sink of some sorts?

> That's all for the sound card. So we need a very minimum sink module for PA.
> What's the minimum requirement for this sink? Could the sink just blindly
> dump the audio data to the audio driver?

In general: yes this is possible. Some sinks (e.g. module-alsa-sink)
do a lot of thing, but at the heart of the sink is always the transfer
of pcm data. You could look for ideas of how to implement this in
module-oss-sink or module-pipe-sink.

Most sinks also try to account for clock differences between the sink
clock (audio hardware samplerate) and host clock (computer and pulse's
samplerate) beyond simply dumping audio data at a fixed rate.

> Regards,
>
> Dengyi Wang

Maarten