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
