gstreamer a2dpSource plugin

gstreamer a2dpSource plugin

[alistair.rodger]

Hello,

I am looking for some help getting audio out of the bluez stack using 
gstreamer? Are we still using an alsa source or should we be using the 
MediaTransport file descriptor.

I am able to generate a sink file descriptor, using the simple-endpoint 
script, but don't know which gstreamer plugin to use.

I am able stream to a device using the a2dpsink.

Sincerely,
alistair

Re: gstreamer a2dpSource plugin

[Luiz Augusto von Dentz]

Hi,

On Sun, Aug 12, 2012 at 7:38 PM, alistair.rodger
<alistair.rodger@ntlworld.com> wrote:
> Hello,
>
> I am looking for some help getting audio out of the bluez stack using
> gstreamer? Are we still using an alsa source or should we be using the
> MediaTransport file descriptor.
>
> I am able to generate a sink file descriptor, using the simple-endpoint
> script, but don't know which gstreamer plugin to use.
>
> I am able stream to a device using the a2dpsink.

What do you mean by which plugin to use? You are using a2dpsink
already, I don't think I got what you want.

I normally test using the following pipeline:

gst-launch -v audiotestsrc ! audio/x-raw-int,channels=2 ! audioconvert
! sbcenc ! a2dpsink
transport=/org/bluez/{PID}/hci0/dev_AA_BB_CC_DD_EE_FF/fd0

-- 
Luiz Augusto von Dentz

Re: gstreamer a2dpSource plugin

[alistair.rodger]

I am trying to stream_from_  the device to a local sink.  I am therefore looking for something like;

gst-launch alsasrc device=bluetooth ! sbcdec ! .....
or

gst-launch a2dpsource transport=/org/bluez/{PID}/hci0/dev_AA_BB_CC_DD_EE_FF/fd0 ! sbcdec ! ...

preferably the second option as this would use SBC not PCM.

But to clarify, I have been asked to investigate this as part of a product we are developing.  So I am trying to understand the approach we should take.  As an embedded device we cannot support PulseAudio but instead have been using gstreamer.  I can stream_from_  our device using gstreamer but, I understand, the only way to stream to a device, using the higher quality a2dp sbc codec, is using pulse audio.

There are examples on the web using "gst-launch alsasource device=bluetooth ! ..." but I believe this has been deprecated and can only support the SCO headset profile "low" quality audio.

So what I am trying to determine is;

1) Is there a gstreamer source plugin which would take the audio out of the bluetooth stack and pipe it to the "sbcdec" plugin, from which I can pipe it to something like "alsasink"?
2) is it possible to stream the higher quality audio over alsasrc, or is alsa fundamentally only PCM ?
3) Is our only option to create or commission a gstreamer plugin?  If so what steps should we take to pursue its creation.

Sincerely,
alistair