Speex dev - Mar 2006 - about AEC Demo

Hi:

  I download the latest version of speex.And I test
AEC.I use testecho.c to do this job.According to
source code:
   while (read(ref_fd, ref_buf, NN*2))
   {
      read(echo_fd, echo_buf, NN*2);
      speex_echo_cancel(st, ref_buf, echo_buf, e_buf,
noise);
      /*speex_preprocess(den, e_buf, noise);*/
      write(e_fd, e_buf, NN*2);
   }

I feed mic and spk signal to ref_buf and echo_buf and
record e_buf.But I found the effect of AEC is not
good.Who can tell me where is wrong?And I suspect that
the signal I input is wrong,if possible who can give
me some example signal?And if I generate this two
signal by the following method,is it OK?My method is
:delay and decrease one segment of audio signal,then
regard them as mic and spk signal,is it OK?


	

	
		
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