[MPlayer-users] down-mix to stereo

[Zongyao QU]

Clément Bœsch <ubitux <at> gmail.com> writes:
> There is a pending patch I'm actually developing. I need to do
> finish it but there is pre-working version you can find it:
> http://lists-archives.org/mplayer-dev-eng/32379-automatic-downmix.html
> 
> You can follow the thread if you want to know why it's still pending.

Thank you for the info.
I am interesting in the reason it was not included into the src.

After read the src,
I found I still do not know the answer,
does mplayer have its own channel map definition?
or the channel map is decoder depended?

furthermore, 
would you please tell me how to calculate the coefficients?