[pulseaudio-discuss] Conditional up/down mixing

[Colin Guthrie]

Hi,

I could have sworn this was asked about on the ML recently but perhaps
it was just IRC as I cannot for the life of me find the message :s

Anyway, someone was asking about their 5.1 capable card and how they
would prefer that stereo streams were not upmixed as their sound
receiver does a better job of upmixing (e.g. Dolby ProLogic or similar
gubbins).

I was thinking about this today and I think this is a pretty common
setup. I think I may actually have need to do that in my own setup now
I've finally gotten around to configuring it up in a vaguely working way!

So what I was thinking was some way to defining the mixing profile (via
simple module argument) that simply lists (comma separated) the channel
counts that are permitted for remixing.

The remix = yes/no still works too but inverses the logic of the
remix_profile argument.

e.g. remix="yes" remix_profile="2" means it will *not* remix 2 channel
sound to the sinks channel count.

whereas remix="no" remix_profile="1,3,4,5,6,7,8,9,10"  means much the
same thing, but only as far as 10 channels.

Obviously remix_profile is fully optional and remix= works as currently
if specified on it's own.

I've not analised how the code works to see how much hassle this would
be to implement, but if this sounds like a vaguely sensible idea, I'll
look at cooking up a patch.

Col


-- 

Colin Guthrie
gmane(at)colin.guthr.ie
http://colin.guthr.ie/

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