[pulseaudio-discuss] GSoC: Call for project ideas

[Tanu Kaskinen]

On Mon, 2013-03-25 at 16:51 +0000, Arun Raghavan wrote:
> On Mon, 2013-03-25 at 18:09 +0200, Tanu Kaskinen wrote:
> [...] 
> > > The simplest idea I can think of to deal with this meaningfully is to
> > > wrap a sink/source around a GStreamer pipeline to offload all that work
> > > that we don't want to duplicate in PulseAudio .
> > > 
> > > On the sink side, we'd hook up to an appsrc to feed PCM data to a
> > > pipeline. The pipeline would take care of encoding, RTP packetisation
> > > and possibly a corresponding RTCP stream. This would allow codec
> > > selection to be flexible, and in the distant future, could even support
> > > taking encoded data directly.
> > > 
> > > On the source side, we'd hook up to an appsink, receiving PCM data from
> > > the pipeline. The pipeline would take care decoding whatever the format
> > > is, take care of RTCP and maybe more advanced features such as a jitter
> > > buffer and packet-loss concealment (all of this can be plugged in or
> > > not, depending on configuration).
> > > 
> > > Doing it this way means you're using a better RTP stack that gets
> > > attention from a number of other use cases (plus assorted related
> > > goodies) and support for multiple codecs.
> > > 
> > > Thoughts?
> > 
> > I like the idea of offloading stuff to GStreamer very much.
> > 
> > Do you follow GStreamer development closely? If I've understood
> 
> Not very closely, but I do some periodically work on stuff in GStreamer
> (and have commit access).
> 
> > correctly, GStreamer hasn't supported rewinding in the past, has there
> > been any talk about that lately? Lack of rewinding support in any part
> > of the audio pipeline causes bigger or smaller problems. I don't think
> > it's a critical problem in this particular case, although rewind support
> > would be useful in this case too. If we would like to use GStreamer for
> > implementing filters, rewind support would be pretty mandatory.
> 
> The idea I have is separate from filters - it's really only about being
> able to use GStreamer for codecs + networking (RTP).

Sure. It's just very tempting to think beyond just that. GStreamer has
so much stuff that PulseAudio could reuse, if only there was rewinding
support.

-- 
Tanu