Phonon's backends to JACK.

[Colin Guthrie]

'Twas brillig, and aCOSwt at 11/06/11 20:59 did gyre and gimble:
> On Saturday 11 June 2011 18:58:54 Colin Guthrie wrote:
>> 'Twas brillig, and aCOSwt at 11/06/11 14:32 did gyre and gimble:
>>> Well well... Some help would be... hmmm... helpful !
>>
>> Just use PulseAudio and it's module-jack-sink.
>>
>> This allows all backends to output to Jack.
>>
>> Col
> Thank you Colin  for answering.
> Thanks now to Michael Palin...
> <<Well well... Is there anybody else I could talk to ?>>
> 
> I am aware of and appreciate the hard work you personally achieved so that... 
> << KDE + PulseAudio != Sucks >>
> 
> Nevertheless... Are you seriously suggesting I should cascade 3 sound servers 
> ?
> If, apart from xine's backend, it comes as being the only possible solution 
> then I think I'd rather select the Alsa !default output and route this to Jack 
> thanks to the snd_aloop driver as I already do with flash, skype and other 
> Jack unaware thingies.

Well Phonon is very much about consumer audio, not pro-audio. Likewise
most of the apps in question are not pro-audio and are consumer focused.
PulseAudio is also very much consumer focused (paying particular
attention to e.g. power savings for use on battery powered and embedded
systems).

IMO it makes perfect sense to have all the consumer focused apps playing
to PulseAudio and all the pro-audio apps playing to JACK. As upstream
projects both PA and JACK are agreed on this principle.

When you use JACK you're doing so for very specific reasons. No one
would really want to run JACK on a standard consumer system, so it's
typically for people doing some degree of pro-audio work. This being the
case you very much want to nuke any inappropriate sounds. Therefore
simply turning off the connection from PA to JACK it becomes relatively
easy to put up a brick wall between any consumer apps that are running
or start up and your pro-audio work.

Also, keep in mind that phonon is *not* a sound server. It's a library.
PA and JACK are the servers, so it's not cascading 3 sound servers, just
2. If you use GStreamer backend in phono you should get a mostly zero
copy ccommunication between the PA client and PA, so the overheads here
are not overly significant (and again we're dealing with the consumer
side of the fence anyway).

HTHs

Col


-- 

+------------------------+
|     Colin Guthrie      |
+------------------------+
| http://colin.guthr.ie/ |
+------------------------+