Re: [linux-audio-user] Common linux audio layer

Brad Fuller wrote:
> I'll try to bottom line my reply to you and hope I can encapsulate
> Christoph's original point:
>
> He wants to be able to start an audio app and hear it's output. He
> doesn't want to see a dialog box pop-up exclaiming that the audio device
> is blocked by another app.
>
> This is what he (or maybe it was me) is referring to regarding creating
> an audio system for users.

Brad,

Thanks for this nice summary / (re)starting point.

At the risk of recomplicating the issue, I guess some complication is a
result of the Linux multiuser and networking capabilities.

I haven't used Windows beyond Win95, maybe someone can answer how
Windows in the multiuser implementations handles these three situations
(are there more):

   * If there is more than one user on a machine (each with his own
"terminal" (i.e., keyboard, CRT, mouse and *sound card and speakers*),
and one of those users starts an audio application, what does Windows
do? (Presumably, the right thing is that Windows notes which user
requests the application and routes the sound to his sound
card/speakers.)

   * If there is more than one user on a machine (each with his own
"partial terminal" (i.e., keyboard, CRT, mouse, but they *share a common
sound card and speakers*), and one of those users starts an audio
application, what does Windows do? (I'm not sure of the right thing
here, my guess is that the default would be to route the output to a
mixer driving the common audio card, with easily accessible options to
do things like mute the existing sound output, or mute the new
application's output, or ???)

   * If there is more than one user on a machine (but the user in
question is logging in remotely (as via Telnet, ssh, remote X, or
similar), and one of those remotely logged in users starts an audio
application, what does Windows do? (I'm guessing that the right thing
is to route the audio output back to the remote user (somehow) and not
interfere with the audio output of the "local" computer, again with
options to route the output to the sound card of the local computer.)

Of course ( ;-) ) for the simplest case, (a single user on a single user
machine), the sound application should be default simply route the sound
to the (single) (local) sound card, mixing the output with that of any
other audio applications, with options to mute either the output of the
old sound application(s) or the new sound application.

I guess part of my point is that the "proper" behavior needs to be
agreed upon for each of these cases (and others?), before a complete
resolution can be developed.

Randy Kramer

PS: Aside: Until recently, I was a lurker on some of the Xfree86 and
(what's the new one, X.org?) mail lists, and one or both of these
organizations were considering somehow dealing with audio issues similar
to the above. I have no idea how far along they are with such efforts
(or whether they've since decided to drop the issues.)
Received on Sun Jan 9 00:15:09 2005