Re: [linux-audio-user] New Sound Subsystem Needed For Qt4/KDE4

From: Mark Constable <markc@email-addr-hidden>
Date: Sat Jul 30 2005 - 00:40:00 EEST

On Saturday 30 July 2005 06:51, Christoph Eckert wrote:
> > I have no say in the matter but I would
> > like to see something like qjackctl ported to KDE4 and
> > usable from within kcontrol, basically, Jack embedded into
> > the system from the ground up.
>
> This will not happen.

This is an explanantion from kde-multimedia@email-addr-hidden as to just
why it would seem to be a problem...

 The design is basically flawed for desktop audio since it
 delegates real-time low-latency work loads through unix
 pipes to the audio applications. You cannot expect all
 audio applications to run real-time and you can not expect
 users to apply custom patches that allow jack to hand out
 real-time privileges.

As far as I can envisage, by the time KDE4 beta starts shipping
that all/most distros will also be shipping at least a 2.6.12
kernel with a rtlimit patched PAM. Certainly by the end of this
year.

> > My general question, to those who know far more than me, is
> > just what would be the ideal sound subsystem for KDE in
> > 2006 seeing there is a clean slate and an opportunity to
> > get it right from the get go ?
>
> I've been discussing this with Scott Wheeler on thios years
> Linuxtag. Similar to Linus Torvalds, the KDE team simply
> waits what will mature most until the day a decision must be
> made.

If that means "least problematic" then sure, if "most mature"
also means most widely deployed for any audio work that matters
then the choice probably should be JACK.

> I guess JACK will *not* be an option for the KDE team because
> it's not configured on every distro per default and JACK
> isn't platform independent.

It runs on Mac OSX and probably other unices using Portaudio
and consider the timeline for KDE4.

> For this reasons, it seems to be more probable that something
> like gestreamer will be chosen, and gstreamer will then have
> a JACK sink.

An extra complex layer on top of the one that really counts.

> For audio stuff, I dislike it, I'd like to see JACK beconimg a
> standard desktop soundserver.

KDE4 has the opportunity (maybe) of doing this. Once another
subsytem gets into the SVN repository then JACK will never
become the default option. Right now, in mid 2005, there is a
small window of opportunity for JACK to become the default
sound server for one of the major linux desktop systems. If
this were to happen then we'd (linux) have half our future
desktops come by default with a world class professional audio
subsystem second to none. Hello Hollywood.

> But gstreamer has some further advantages: It's not specific
> for audio only. For example (if I got it right) it can also
> provide a video stream from one device to multiple
> applications, so it also solves one problem JACK solved for
> audio for video applications.

It kind of half solves both the audio and video issues.

Does anyone on this list use gstreamer to get Rosegarden,
hydrogen, ardour and JAMin to work together ?

Does gstreamer allow kino and cinelerra to work together ?

> I personally would be happy if JACK would be chosen, so we had
> *one* *tru* solution for desktop as well as for professional
> use, comparable to coreaudio on Mac OS X. But I fear that
> there will be another decision and this will again delay
> finding *the* *true* solution :( .

Fear the fear of a decision like this being made by folks that
do not use the wonderful ALSA/JACK enabled audio toolset that
we are all so familiar with on this list.

> I include Scott Wheeler in the CC of this mail.

Thanks.

--markc
Received on Sat Jul 30 04:15:06 2005

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