[pulseaudio-discuss] These ideas I've had for the better part of a month, forgive me for there length.

[pl bossart]

>> The next stream type should be a pulse audio internal type(s) used for
>> the mixing of mp3/ac3 and perhaps dts streams.  It's my understanding
>> that ac3 uses vectors to describe 6 channels of sound much like a 2ch
>> mp3.  If I'm not mistaken these vectors can be combined mathematically
>> as-is to represent the combination of two sounds.  This would be a great
>> achivement over any uncompress/combine/recompress senerio.
>
> Do you have any pointers to how this is done? If it's true that there
> really is a way to mix compressed streams without uncompressing first,
> then maybe volume adjustment is possible too?

Nah. no way you can mix streams without decompressing
(dequantization+inverse transform). The only thing you could do is mix
in the transform domain if both streams used the same transform and
window size, not a very common case.
-Pierre