Hi Mauro, I could not participate at your Summit, but may have an input to the media-controller in DVB - see below. On Wed, 22 Apr 2015 15:31:46 -0300 Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx> wrote: > This is the first draft for the Linux Media Summit Report. > > Please note that the items 3 to 5 are not in good shape. In special, > nobody took Etherpad notes on item 4. > > Please review. I'll publish a second (final?) draft after having some > feedback. > > Regards, > Mauro > > - > > Linux Media Summit - March, 26 2015 - San Jose - CA - USA > > > Attendees: > > > Angelos Manousaridis <amanous@xxxxxxxxx> > Bob Moragues <bob.moragues@xxxxxxx> > Chris Kohn > Guennadi Liakhovetski <g.liakhovetski@xxxxxx> > Hans Verkuil <hverkuil@xxxxxxxxx> > Hyun Kwon > Karthik Poduval <karthik.poduval@xxxxxxxxx> > Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx> > Michal Lebik > Mohammed CHERIFI mcherifi@xxxxxxxxx > Rafael Chehab <chehabrafael@xxxxxxxxx> > Ron Birkett > Schuyler Patton > Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> > > 1) Media Controller support for DVB > Mauro presented a set of slides (add link) showing how the DVB > pipelines look like and underlined that several topics needs to be > addressed by the Media controller: > > a) dynamic creation/removal of pipelines > b) change media_entity_pipeline_start to also define the final entity > c) how to setup pipelines that also envolve audio and DRM? > d) how to lock the media controller pipeline between enabling a > pipeline and starting it, in > > How to do complex pipelines in DVB? > > - The DVB demux can filter MPEG-TS traffic (either in hardware or in > software) and can send multiplexed TS to the dvr node, elementary > streams to the demux node and can create network interfaces for > elementary streams (ES) via the net node. > - a given set of elementary streams can go to one of those three > options only, or it can be sent directly to a GPU and/or an ALSA > pipeline. > - there is support for hardware PID filtering at the Kernel, but no > support (yet) for a real hw demuxer that splits the MPEG TS into > separate DMA MPEG-TS and/or ES streams. > - frontend device node is to be attached to the demod entity and it > will control the demod, the tuner and a possible LNA via the active > Media Controller links. > - dvr/net/demux device nodes are attached to the demux entity. > - the net interfaces are not (yet) represented via MC: we need the > ability to remove entities dynamically for that, and we are not > really sure if we want this at all. So, it as agreed to wait for > support for removing entities to arrive, then this need can be > discussed again. > - For now we can safely assume that there is only one Satellite > Equipment Control (SEC) in each active data path that goes through a > tuner/demod. So each frontend will control just one SEC. Should we > encounter really complex scenarios, then we should consider having > device nodes for SEC entities. What about demod-diversity: demods of some manufacturers can be used to combine their demodulated symbols and, due to their different antennas and RF-paths, improve the overall reception quality. If we ever have someone contributing in this area with hardware-drivers, it would be nice to have the user-space possible to select demod-combinations. It should be possible to add and remove a demod to a diversity-chain when and when not being tuned to a channel. regards, -- -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
