[MPlayer-users] Mplayer & DD5.1 via SPDIF - I have only DD2.0: why ?

[Matthias Schwarzott]

On Monday 26 December 2005 22:46, Sasza wrote:
> Hi all,
>
> I have DIVX file with 5.1 sound, and I want to play it via MPLAYER.
> My MythTV (R5A22) system is connected via digital SPDIF connection to my
> Home theater aplituner.
>
> Launching mplayer with various parameters gives at best DD2.0 sound.
> DD5.1 is impossible :-(
> I spend literally days to trying solve this issue (many hours googilng &
> searching various forums)
> System is: EPIA M10k, KnoppMythR5A22.
> Used AVI file plays nicely DD5.1 under xine (unfortunately xine CPU
> consumption is about 50% vs 25% in mplayer. Also I have problem with AVI
> subtitles in xine)
>
> Pls find below mplayer logs for different cmd line option used:
>
>
> 1. "mplayer -channels 6 -ao alsa -ac hwac3, file.avi"

To my knowledge this should be done like:
# mplayer -ac hwac3, file.avi


I have this in my .mplayer/config:
ac=hwac3,
ao=alsa

If your amp shows it plays DDx.y this is ok.
And if your amp shows only DD2.0 then your ac3 stream IS 2.0 and you can do 
nothing to change that.

You can check this by doing
# mplayer file.avi -ac a52 -frames 0 2>/dev/null |grep ^AC3
AC3: 2.0 (stereo)  48000 Hz  448.0 kbit/s

This means ac3-stream is only stereo, but this does not mean that the complete 
avi is encoded it stereo but only the first-audio frame.

Matthias

-- 
Matthias Schwarzott
Gentoo Developer
http://www.gentoo.org