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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hello all,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m a hardware person who has recently found himself
thrust into a software role. So, please forgive any ignorance in the following
questions. I’ve tried to do my homework reading the relevant manual pages
and investigating the Doxygen documentation. :-)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>We’re investigating acoustic echo cancellation
solutions for a speech application. Our hardware will be a TI C64x+ series
processor (DM6467) which has both a DSP and ARM9 core. Our audio will be sampled
at 8kHz and fed in through the I2S ports on the DM6467, echo cancelled, and
then encoded in G.711. As such, I’m really interested in the echo
cancellation component of Speex, but not in the encode/decode. Finally, only
one channel of audio needs to be echo cancelled in the system. So, here come
the questions. :-)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>1. Is it possible to call speex_echo_cancellation() on audio
frames not already encoded in Speex?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>2. Can anyone compare / contrast the features of Speex’s
echo cancellation versus those of, say, Ittiam (http://www.ittiam.com/pages/products/aec.htm
) or Adaptive Digital? (http://www.adaptivedigital.com/product/echo_cancel/adt_aec.htm)
Obviously these are expensive and powerful commercial packages which probably
don’t compare well with a package like Speex, but I’d just like to
get a sense of what the differences are.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks for your help!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Mike<o:p></o:p></span></font></p>
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