[MPlayer-users] Pan downmixing + LFE Problem

Tashfeen Bhimdi tbhimdi at bhimdi.com
Mon Apr 26 22:13:29 CEST 2004


>>1) Any fix to mix the LFE into the FL and FR channels? (like WinDVD in 
>>windows)
> 
> 
> Well, I have a partial solution yet:
> 
> -channels 6 -af pan=6:100:0:0:0:100:100:0:100:0:0:100:100:0:0:100:0:0:0:0:0:0:100:0:0
> 
> This works with the front left / right speakers and mixes the center and
> lfe into it. But no rear left / right :-///
> 
> (I use a SBLive Value Edition with a Logitech Z560 4.1 Speakerset)


OK, now this is strange.  I entered that line above into my config 
(converting the integers into floats, according to the mplayer docs they 
should be floats), and LFE started working great.  The rear speakers 
continue to work for me too.

Here is what I have now, I really hope it helps your Live+4.1 setup, 
which is similar to an Audigy+4.1 setup I have:

(only audio related entries listed)
ao=alsa1x   #alsa driver
cache=8192  #may help
af-adv=2    #optimal audio filters
srate=48000 #probably better than the live/audigy hardware conversion
af=resample=48000:1:1 #better
channels=6
af=pan=6:1:0:0:0:0.5:0.5:0:1:0:0:0.5:0.5:0:0:1:0:0:0:0:0:0:1:0:0:0:0:0:0:0:0:0:0:0:0:0:0

Make sure you have the latest ALSA drivers installed (making sure to 
edit your .asoundrc file to add hardware mixing).  Run alsamixer (or 
gnome-alsamixer) and jack up the "PCM Surround" and "Surround" levels 
since they're the volume control for the rear speakers (Surround is 
muted by default).  Enable "Tone" otherwise the base/treble controls 
won't work.

For a 4.1 setup, 6 channels with Pan work, while 4 channels don't.  This 
HAS to be a bug in mplayer, since the same line above written for 4 
channels doesn't mix the LFE channel, but change it into 6 channels and 
mute the last 2 channels (effectively making it 4 channels), and LFE 
starts working.

5.1 -> 4+mixed LFE
LFE WORKS:
channels=6
af=pan=6:1:0:0:0:0.5:0.5:0:1:0:0:0.5:0.5:0:0:1:0:0:0:0:0:0:1:0:0:0:0:0:0:0:0:0:0:0:0:0:0

LFE DOESN'T WORK:
channels=4
af=pan=4:1:0:0:0:0.5:0.5:0:1:0:0:0.5:0.5:0:0:1:0:0:0:0:0:0:1:0:0

-- 
Tashfeen Bhimdi




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