[pulseaudio-discuss] association of pa_stream to mixer input channel

[Colin Guthrie]

'Twas brillig, and jayan john at 14/06/11 06:12 did gyre and gimble:
> 1. Does the pa_stream_connect_playback() call allocate an input channel
> on the mixer and connect it to the sink device?

Not really what you are referring to as "the mixer" or an "allocated
input channel" here but this command does indeed connect a playback
stream. This will be needed if you want to playback any audio. After the
stream is connected it will be allocated to a sink according to various
routing decisions in PA itself. It may at some point be moved to a new
device at a later time (unless you pass the PA_STREAM_DONT_MOVE flag IIRC).

> 2. Would it allocate 6 input channels on the mixer if I have a 5.1
> channel map for my pa_stream?

Again, I'm not really sure what "the mixer" refers to here. But your
stream will have as many channels as you say it has in it's channel map
like you say. You can ultimately connect a stereo stream to a 5.1 sink
and PA will upmix, and likewise you can connect a 6ch stream to a stereo
sink and it will downmix.

Ultimately, as an app developer, you should just care about your stream
and not worry about the sinks :)

Col


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

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