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</o:shapelayout></xml><![endif]--></head><body lang=RU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Yes, it's absolutely unnecessary to use speex codec. You can encode the echo cancelled auido data</span><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#333333'> with any codec you want.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#333333'>The Echo Canncelation API is here - </span><a href="http://www.speex.org/docs/api/speex-api-reference/group__SpeexEchoState.html">http://www.speex.org/docs/api/speex-api-reference/group__SpeexEchoState.html</a><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I would advice you to look at </span><span class=apple-style-span><b><span style='font-size:10.5pt;font-family:"Arial","sans-serif";color:black'>speex_echo_cancellation</span></b></span><span class=apple-style-span><b><span style='font-size:10.5pt;font-family:"Arial","sans-serif";color:black'> </span></b></span><span lang=EN-US>function but you will have to sync playback and capture streams by yourself.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I've used GSM, iLBC and Speex codecs with Speex AEC and it works fine.</span><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#333333'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Best Regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Anton A. Shpakovsky<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> speex-dev-bounces@xiph.org [mailto:speex-dev-bounces@xiph.org] <b>On Behalf Of </b>Christopher Adoremos<br><b>Sent:</b> Wednesday, September 29, 2010 4:39 PM<br><b>To:</b> speex-dev@xiph.org<br><b>Cc:</b> jean-marc.valin@usherbrooke.ca<br><b>Subject:</b> [SPAM] [BombData][alltestmode] [Speex-dev] Using Speex Echo Canceller<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hi<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Is it possible to use only the speex echo cancellation module w/o using the speex codec?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Here's the scenario:<o:p></o:p></p></div><div><p class=MsoNormal>1. I have my voice recorded in PCM audio file format<o:p></o:p></p></div><div><p class=MsoNormal>2. I want to cleanup the recorded voice by removing any echo included in the audio file/buffer<o:p></o:p></p></div><div><p class=MsoNormal>3. can I just use the ff APIs?<o:p></o:p></p></div><div><p class=MsoNormal> - SpeexEchoState* speex_echo_state_init()<o:p></o:p></p></div><div><p class=MsoNormal> - int speex_echo_ctl()<o:p></o:p></p></div><div><p class=MsoNormal> - void speex_echo_capture()<o:p></o:p></p></div><div><p class=MsoNormal>4. then, will it be possible to encode the output buffer from speex_echo_capture() to any codec?<o:p></o:p></p></div><div><p class=MsoNormal> Like G711? GSM? etc....<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I'm quite new to audio format concepts/development, so if you have any ideas your advice is highly appreciated..<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks in advance<o:p></o:p></p></div><div><p class=MsoNormal>Chris A<o:p></o:p></p></div></div></body></html>