Re: [ecasound] crazy using alsa loopback device

Hi,

On Fri, 1 Feb 2008, Carlos Hernandez wrote:

> I'm a new ecasound's user, it's an amazing tool.

welcome on board! :) Sorry for the somewhat late response.

> well, I want to send audio from one application to another using
> snd-aloop module (ALSA) and ecasound. this is what I've done.
[...]
> # ecasound -i alsaplugin,1,1 -o alsaplugin,2,0
[...]
> warning! playback underrun - samples lost! Break was at least -757531646.38 ms long.
> warning! playback underrun - samples lost! Break was at least -757531646.34 ms long.
> warning! playback underrun - samples lost! Break was at least -757531022.53 ms long.

It seems the clocks are not synced and this will cause the streams go out
of sync sooner or later.

I recommend taking a look at JACK [1]. It offers a much better mechanism
for routing audio between apps, and you can use it with ecasound as well.
Also, there's a separate program called Jack Diplomat [2] that can sync
two different systems (driven by different clocks).

[1] http://jackaudio.org
     One intro to JACK is at
     http://w3.linux-magazine.com/issue/67/JACK_Audio_Server.pdf
[2] http://www.archivesat.com/JACK_developers/thread771821.htm
     http://spark.woaf.net/jack_diplomat-0.70.tar.bz2

> Everything works fine the first 8-10 seconds... then underruns again.

Yes, so at first the clock drift stays within the internal buffers and
audio is ok, but sooner or later the drift adds up and you start getting
continuous buffer under/overruns.

-- 
  links, my public keys, etc at http://eca.cx/kv
-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Ecasound-list mailing list
Ecasound-list@email-addr-hidden
https://lists.sourceforge.net/lists/listinfo/ecasound-list