Thank you for your reply. My purpose here is to cancel the feedback echo that comes from the loudspeaker into the mic. The echo canceling API I'm using (libspeex) has the folowing function for echo cancelling: void speex_echo_cancellation(speex_context[in], mic [in], loudspeaker[in], output_without_echo[out] ) Basically it needs to do some mathematical processing on the mic input to remove the echo from the loudspeaker and put the result in the last parameter. I need to feed this function with the samples from input mic and the samples from the loudspeaker and the delay between these two signals should be minimal for best results. I'm looking for some help on how to setup this using alsa. I dont even know if it is possible and if it is what is the best aproach to do so. Thank you very much, Daniel sonofzev@xxxxxxxxxxxx escreveu: > There will always be some latency between mic input and speaker output when monitoring via the system, regardless of OS driver or subsystem.. > > You are also very likely to get feedback issues in this scenario. > What is you rpurpose and maybe we can make some suggestions to resolve your particular issue. > > > > > > On Tue Jan 27 15:05 , Daniel sent: > > >> Please, >> >> Is there any way to keep mic and loudspeaker signals in sync using alsa >> (echo cancellation purposes)? >> >> If so, how can I get these signals ??? >> Is there any kind of notification from alsa/kernel/mixer (or whatever) >> to bring these two signals synchronized ? >> >> Thanks in advance! >> Daniel >> >> ------------------------------------------------------------------------------ >> This SF.net email is sponsored by: >> SourcForge Community >> SourceForge wants to tell your story. >> http://p.sf.net/sfu/sf-spreadtheword >> _______________________________________________ >> Alsa-user mailing list >> Alsa-user@xxxxxxxxxxxxxxxxxxxxx >> https://lists.sourceforge.net/lists/listinfo/alsa-user >> ) >> > > > ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
