[mythtv] [mythtv-commits] Ticket #1104: multichannelaudio support

[Ma Begaj]

2008/1/16, Jack Perveiler <perveilerj at yahoo.com>:
>
> --- Robin Gilks <g8ecj at gilks.org> wrote:
>
> >
> > >>
> > >> Sorry Mark - still confused...
> > >>
> > >> Are you saying that if my only connection is S/PDIF from my frontend to
> > >> my
> > >> amp then it will only reencode if I change playback speed? Otherwise I
> > >> have to use 6 analog connections?
> > >>
> > >> Example
> > >> Standard def DVB-S recording with stereo sound. I have ALSA:Default as
> > >> the
> > >> output device for S/PDIF output to the amp. No analog connections at
> > >> all.
> > >> The amp analyses the stream as PCM48.
> > >>
> > >> If I select 5.1 in setup, the digital stream to the amp is always
> > >> displayed as PCM48 stereo. It does not encode it to AC3. Will it become
> > >> 5.1 if I change the playback speed?
> > >
> > > I assume you have passthru enabled as you should have.
> > > leave #channels set to stereo (2ch). you dont need 6ch mode at all.
> > > any AC3 5.1 or DTS5.1 source material audio will be passed through as
> > > digital via spidf.
> > > any 2ch source material audio is passed via spidf as 2ch PCM48 and your
> > > amp
> > > does the upmixing.
> > >
> > > reencoding only occurs if the source material is 6ch and you have passthru
> > > enabled and timestretch != 1.0
> > > In this case it still appears via spidf as AC3 encoded 5.1 to your amp.
> > >
> > > hope this is clear.
> >
> > It is a lot better thanks Mark but not 100% :-(
> >
> > So this ticket is not a substitute for the upmixing my amp is capable of -
> > I missed that entirely (in fact I thought that is what is was!), I have to
> > change modes on the amp if I throw 5.1 (eg. from a DVD) at it rather than
> > have MythTV do it all.
> >
> > I thought that it would output 5.1 irrespective of the source so I could
> > put yet another remote into a drawer. Not to worry - I can live with a few
> > button presses...
> >
>
> It would still be desirable to use software upmixing for me because:
>
> 1) My amp takes a second or 2 to switch between DPL and 5.1 modes, which means
> after commercials (DPL, usually) I miss a second or 2 of audio while the
> receiver switches back over to 5.1 mode.  Having an unbroken stream of 5.1
> would be great here.
>
> 2) My receiver has DPL (not DPL2), and decoding 2 channel streams mainly means
> "send everything out the center channel".  It sounds like your software upmixer
> would do a much better job.
>
> Just my 2 cents...
>
> --Jack
>

I set in General Settings Surround51 and 6ch.
Sound in Mythmusic does not work for me if I use "default" (or in
German "Standard") in the menu. I have to enter manually
"surround51..." to make it work. Is it only me with this problem?