PulseAudio and sound apps (was: Re: Orphaning a few packages)

[Lennart Poettering]

On Wed, 15.04.09 10:22, Kevin Kofler (kevin.kofler at chello.at) wrote:

> Orcan Ogetbil wrote:
> > I re-orphaned portaudio. I see that it is patched to work with
> > pulseaudio, which, I think, must be banned from the surface of Earth.
> > I am not planning to maintain a package with such a patch.
> 
> PulseAudio is the default sound solution in Fedora, so all packages using
> sound SHOULD support it.
> 
> IMHO, we should:
> * find some solution for JACK apps to work out of the box, without
> reconfiguring PulseAudio to work on top of JACK. Maybe this involves

As Matthias mentioned PA will now hand over audio device access to
JACK if JACK asks for that. When JACk is done running it will hand the
access back.

> running JACK on top of PulseAudio (something which currently doesn't work
> because JACK does not support non-mmap ALSA devices nor the native
> PulseAudio protocol), maybe this involves starting up JACK when needed and
> having it load the JACK modules into PulseAudio and rerouting running
> PulseAudio streams to JACK at runtime (which can be done without
> interrupting the PulseAudio streams - the problem with that solution is
> that it breaks support for multiple output devices, which work just fine
> when using PulseAudio directly), maybe something else, but in any case a
> solution is needed to make things just work.

No. JACK is a sound server for audio production. PulseAudio is a sound
server for the desktop. Only in very few cases it makes sense to
connect them to each other -- and that should then be configured
manually by the user. While JACK is running PA should go out of the
way. And that's what the JACK folks and I have agreed on and
implemented very recently.

In an ideal world PA and JACK would be one hybrid audio server. But
that's not going to happen anytime soon and it is also questionnable
if it would make sense at all. So the only realisitic short term
solution is having JACK and PA cooperate better. And that should be
the case now. The cooepration logic is in PA 0.9.15. I don't know
which version of JACK actaully added the other side of the story.

> * once that's done, make it a requirement that sound MUST work with
> PulseAudio without manual configuration. PulseAudio MUST be the default in
> all sound-using applications. JACK SHOULD only be used if PulseAudio (and
> any of the compatible APIs, e.g. ALSA, ESD etc.) is not supported (and as I
> explained above, it needs to interoperate with PulseAudio more than it
> currently does). Likewise, aRts (the deprecated KDE 3 sound server) SHOULD
> only be used if outputting directly to PulseAudio is not possible.

JACK should not be used by anything by default, with the exception of
audio production software. 

Arts should not be used by anything at all. Let it die a peaceful
death please. (But I a m bit ignorant of KDE, so maybe I am stepping
on someone's toes by saying something bad bad about arts like that)

Lennart

-- 
Lennart Poettering                        Red Hat, Inc.
lennart [at] poettering [dot] net         ICQ# 11060553
http://0pointer.net/lennart/           GnuPG 0x1A015CC4