[MPlayer-users] dvd (ac3) volume <-> standard (mp3) volume

[Marco Gigante]

On Fri, Jan 10, 2003 at 06:44:23PM -0500, D Richard Felker III wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> 
> > - Is my solution (-aop list=volnorm -af volume=30) the best or 
> >   is there a better way?
> 
> Unfortunately that's the best way I know.

Some time ago I got same problem.
My case was with a 2.0 mp3 downmixed from 5.1 ac3.
I played a bit with -aop and -af with no succes.

Now consider 2 cases.
1) 5.1 ac3:
in older version of mplayer -af volume was
-af volume[=v0:v1:v2:v3:v4:v5:sc:pr:en]
vN: per channel volume

Last CVS version has -af volume[=v:sc:pr:en]
so it seem that newer filter doesn't support per channel
volume adjust.

Ok, this doesn't was my case but now it seem mplayer cannot
manualy adjust per channel volume of 5.1 audio.
Am I missing something?

2) 2.0 audio (ac3, mp3, ogg, ecc.) downmixed from 5.1 ac3:
If 2.0 was bad downmixed and central channel is too low
there is no possibility to adjust it.
-aop volnorm doesn't work since it normalize 2.0 tracks, not
5.1 ones.
-aop volnorm,surround not works either since it decodes to 4.0
and central channel is still low.

Again, am I missin something and I'm wrong?

Since I was not able to solve problem I tried to hack around.
6dBpress audio filter from avidemux seems to solve the problem;
I played a bit with source to port it to -af for mplayer, but
lack of time does me not complete the work.
A sorround filter to decode 2.0 to 5.1, with volnorm, I think
solves the problem for mplayer too.

Any Idea?

--
Marco Gigante