[pulseaudio-discuss] Using pulseaudio with speakup

[Colin Guthrie]

'Twas brillig, and Markus Rechberger at 02/01/10 13:31 did gyre and gimble:
> In practice did you test this with some mpeg players? I wonder if they
> will automatically pause the
> Video.

Of course this wont work unless the applications are aware of the
corking concept. It doesn't work by magic :p

We have several modules that try to emulate this until the apps can
become aware themselves. Gstreamer based apps can now hook into this
information but even then they need to actually listen to it.

In the mean time we can synthesise key events to send the pause/play
keys to the media players (or all applications) via
module-x11-cork-request but this is a bit flaky and sometimes causes
problems (with the skype beta for example it was pausing media players
when skype generated any sound event and caused players to start playing
if they were already in a pause state before the event sounded).

This is why I disabled this module on Mandriva for the time being.

Once apps can handle this natively we can remove this module from a
default setup and eventually deprecate it completely.

> Unless the application starts to timeshift by itself PA will take care
> that the livestream will become corrupted.

Not really. If the application handles corking/uncorking correctly via
it's audio library then it can either timeshift if supported or simply
throw audio in the bit bucket until it's uncorked. If it wants to it can
also disable video. Really this is an application choice tho', so you're
free to implement this as you see fit in your product.

> Does this corking mechanism really just pause the readout of the
> audiosamples?

There is another thread about corking on this list recently so I wont
try to cover it here. The long and short of it is that it is a mechanism
to say "you are not allowed to output sound now"

Col




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Colin Guthrie
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http://colin.guthr.ie/

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