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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hello,</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am testing speex 1.1.6’s echo canceller. I am using testecho.c,
with a few modifications to get it to run on Windows. </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>My problem is that I am unable to get the echo cancellation
to work correctly. I am working on an audio conferencing software, and one
issue we have is sometimes the microphone picks up what is being played through
the headset, resulting in an echo of the other person who is talking. In order
to test this scenario through the echo canceller, I am running two samples through
it. The first is the signal I want to clean – it is my husband talking,
with an echo of myself talking. The second sample is the reference sample –
it is just myself talking. (I used the second sample to create the first, so it
is the exact same wav, with my husband’s speaking placed on top of it.)</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The result has my husband speaking clearly, but the echo of myself
talking is garbled and sounds like the Borg Hive from Star Trek. It’s
more distracting than the original signal was. I have tried introducing delays
to my echo, but it does not help the signal to become clearer. </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I think I am doing something wrong, but I am not sure what.
I notice you are using two samples – play.sw and ref.sw – which are
not included in the source. What do they sound like? Is there a place one can
pick up these files? Is this echo cancellation designed more for musical tones
instead of actual echoes of speech? I know this is experimental and I feel I
may be using it in the wrong way.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>If you want, I can email my samples and the resulting
output.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thank you for your support and for a great product,</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Shana</span></font></p>
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