[pulseaudio-discuss] gst pulsesrc and default caps

Alexey Fisher bug-track at fisher-privat.net
Mon Aug 16 07:23:51 PDT 2010

On Mo, 2010-08-16 at 09:06 -0500, pl bossart wrote:
> >> On Mon, 2010-08-16 at 06:42 +0300, Tanu Kaskinen wrote:
> >> > I guess the problem is that pulsesrc doesn't know
> >> > which source is going to be used before actually starts recording.
> >>
> >> No, that's not the problem. The problem is that pulsesrc doesn't use the
> >> proper flags when creating the stream: PA_STREAM_FIX_FORMAT,
> >> PA_STREAM_FIX_RATE and PA_STREAM_FIX_CHANNELS can be used to create the
> >> stream with whatever parameters are used by the device that the stream
> >> connects to.
> >>
> >
> > Thank you!!! i like this answer :D
> I don't think that solves the problem. The performance issue is due to
> the format/sample-rate conversion.
> Using these flags essentially mean that you will record with whatever
> native sampling-rate is used by the pulseaudio source (as specified in
> daemon.conf) no matter what value is specified when the stream is
> created.. It doesn't mean you are going to record at 16kHz natively in
> pulseaudio. You will still have to go your src in gstreamer.
> -Pierre

It looks like it working for me. Or "resample method: (null)" mean some
thing other? 

1 source outputs(s) available.
    index: 0
        driver: <protocol-native.c>
        state: RUNNING
        source: 2
        current latency: 0,00 ms
        requested latency: 27,56 ms
        sample spec: s16le 1ch 16000Hz
        channel map: mono
        resample method: (null)
        owner module: 9
        client: 33 <gst-launch-0.10>
                media.name = "Record Stream"
                application.name = "gst-launch-0.10"
                native-protocol.peer = "UNIX socket client"
                native-protocol.version = "16"
                application.process.id = "13431"

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