My use case is just add a backgroud music to my voice record.
 
Thanks for you suggestion for JACK.
 
But can i use "~/.asoundrc" or "amixer" to realize it?

2011/4/18 Bill Unruh <unruh@physics.ubc.ca>
On Mon, 18 Apr 2011, Sergei Steshenko wrote:

On Mon, 18 Apr 2011 00:29:20 -0700 (PDT)
Bill Unruh <unruh@physics.ubc.ca> wrote:
[snip]
Why can you not "mix" them
afterwards, since the stuff going out your speaker surely originated from your
computer anyway.
[snip]

Huh ? How about recording a VOIP session - the stuff going to speaker
originates in somebody else's computer.

Uh, no. It goes through your computer.  But at least you have given me a clue
as to what he might be refering to. (Ie, using it to record skype phone calls
he is making).


One possibility is to use jack to link up the pieces. There have also been discussions in the past as to how to record stuff leaving
the machine.


Regards,
 Sergei.


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William G. Unruh   |  Canadian Institute for|     Tel: +1(604)822-3273
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