Add a muxer selection setting

[pvagner]

Tvheadend currently can provide mkv, mpeg ts, and mpeg ps muxes while streaming.
I have found out verry interesting PR tvheadend/tvheadend#263 . This adds ability to only stream first audio channel. It would be usefull to save bandwidth if I am only interested in audio. If muxer setting is applicable to this project can it be added?

[BtbN]

This add-on doesn't get muxed data. It gets the raw elementary streams via htsp. There is no way to select which streams you want. Tvh always sends them all.

[pvagner]

@andoma has added filter stream command to htsp server.
Do I correctly understand this might enable us to get a stream selection?
I am tallking about commit 535fc25fcc

[BtbN]

Yes, this enables you to select which streams of a subscription you want via HTSP.
But you need to know the ID, and VLC plugins don't have any UI to select which streams you want.

[pvagner]

While watching movie in VLC I can go to the menu audio or video and I
can see video track or audio track in there respectivelly. Usually it
contains all the available streams and an item called disable.
Would there be a way for this plugin to only transmit streams which are
playing?
Or alternativelly I am only interested in audio so perhaps you might be
able to add a setting saying something like "stream audio only" into the
htsp options page.
Or is this too complicated to really make some good use of?

Thanks and greetings

Peter