[MPlayer-users] Getting the best sound from mplayer

[Vladimir Mosgalin]

Hi Grant!

 On 2011.07.22 at 13:20:14 -0700, Grant wrote next:

> > lavcresample provides satisfactory resampling when it's set for high
> > quality mode. So just try selecting higher quality mode for audio
> > filters with -af-adv (check manpage).
> 
> According to the manpage, '-af-adv force=1' (optimized for accuracy)
> is the default.  Is floating point processing with force=5 better?
> lavcresample is used by default according to this:
> 
> http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2004-December/032119.html

I'm not sure. I don't use this one, really; maybe "default" is high
quality. If resampling quality isn't enough for you (which can be
perfectly possible, as imho lavc doesn't provide high quality resampling
unless you manually specify high quality options like higher filter
length and number of polyphase entries or linear interpolation (if you
use it, no need to increase anything else iirc). Then again,
lavcresample is said to use only s16le, so your audio will be
downsampled to 16-bit for sure if mplayer resamples something.


 > No, it will pass output as is. Maybe with *some* specific output drivers
> > it can change sample size or rate automatically, when output driver
> > demands some type of stream, not sure, but it's not the common case.
> 
> Doesn't resampling need to take place in order to downmix the 6
> channels to 2?  My question was meant in the context of that downmix
> and resampling.

No, you can both "cut off" extra channels or do the work like pan filter
does in any sample rate and size. Nothing has to be resampled.

> How can I determine how many channels are in the audio track of an MKV
> file so I can apply the correct pan filter when I play it?

Not sure about this, sorry.




-- 

Vladimir