<FONT size=2> <div>Hi Jean-Marc,</div> <div> </div> <div>Regarding you points:</div> <div> </div> <div>1) Is it ok if the audio is encoded (using Nelly Moser ASAO) and sent to the client and decoded when it is recevied so the AEC is always performed on raw PCM16 8KHZ ?</div> <div><BR>2) The audio is moved in 32ms (512 byte) chunks and the reading and writing to the AEC code will be done by separate threads at regular 32 ms intervals.</div> <div><BR>3) Occasionaly audio is dropped if it has become delayed but a jitter buffer of 120ms is in use.</div> <div> </div> <div>People at different distances from the server will have a slightly different round trip time. Do you think if using a large tail or something we can get near perfect AEC? The same as you get with a hands free phone perhaps?</div> <div><BR>Does it still sound like worth a try? Is Speex AEC as good as it gets or would it be worth contacting some vendors of such
software?</div> <div> </div> <div>Thanks again,</div> <div>Tabby </div></FONT><BR><BR><B><I>Jean-Marc Valin <jean-marc.valin@usherbrooke.ca></I></B> wrote: <BLOCKQUOTE class=replbq style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">Tabitha Flash a écrit :<BR>> Hi, I am looking for AEC software which can be run on the server<BR>> side. This means there will be a fairly constant 600ms or so gap<BR>> between sending out an audio frame and getting it back with echo.<BR>> Could Speex AEC be configured to handle these conditions? <BR><BR>Just use a ring buffer to put the delay back to normal.<BR><BR>> If so, how<BR>> good can I expect it to be?<BR><BR>You'll need to try, but to have any chance of working, the following<BR>conditions must be met:<BR>1) No codec must be used in the echo path (maybe G.711 is OK)<BR>2) There must not be any drift in the sampling clocks<BR>3) There must not be any audio samples lost on the
echo path<BR><BR>Jean-Marc<BR></BLOCKQUOTE><BR><p> 
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