[alsa-devel] ALSA DMIX support without MMAP ?

ANISH KUMAR anish.singh at samsung.com
Fri Jan 15 13:07:00 CET 2010

>For dmix, the stop_threshold should be equal to boundary value, thus XRUN 
>check should never be true. If you got xrun with dmix, something is wrong.
DMIX is working now.

 > but when i am 
> playing with Plug PCM there is some noise in the song why????Is rate 
> conversion algoritm not able to resample it properly?
>The default linear resampler is not very good quality. You may use some 
>sox resamplers from the alsa-plugins package, but they're more CPU 
>intensive. Check google.

Actually i am working on soc platform(android-S3C6410) and wanted to use DMIX and some good resampler for my software mixing instead of current software mixing and resampling in upper layer(Above alsa-lib).DMIX is working fine but this resampling is causing some jitter.During rate conversion it looks for libasound_module_rate_speexrate.so which i don't have so its using default one causing the jitter.
Can i build this .so file (as current way of alsa-plugin downloading will not work for me)?For sox resampler i guess i need to use differnet .so and corresponding changes in asound.conf file??
Can i get speex or sox  resampler code so that i can build it for my system?????
This code(speex or sox) i guess would have been integrated with alsa-lib so that alsa-lib can call corresponding functions of resampler source code. 
 OR simply point me to url as googling is not helping.Everywhere i am getting this "you need to download plugins".This will not work in my case.

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