[Alsa-user] auto upmix in .asoundrc

[Christopher S. <sou...@sh...>]

Hi,

I'm looking for a way to realize an automatic upmix function.

What I got right now in my .asoundrc is a pcm of type route which
distributes channels 0 and 1 to a 7.1 signal.

The problem is, when source is a surround signal, every other channel
than 0 or 1 gets lost. What I want is stereo signals getting upmixed and
everything with more than two channels not getting touched-

I could realize that using a manual switch (like explicitly choosing a
device in the application), but I would like to know whether I could
somehow do it using .asoundrc. What I have in mind is something like a
pcm which determines the number of source channels and calls another pcm
depending on how many it got.

Thanks for any hint!

Christopher Schramm