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<body><div style="text-align: left;">Hi All, <br><br>I am working on my master project to port the Speex Acousic Canceller to FPGA. But I am not able to get a satisfied result in its performance when<br>I integrated it to a SIP softphone as my first step. The SIP softphone calls to a PSTN gateway and lands to my land line phone. I can hear the echo <br>of my every word while I talks on the land line phone. <br><br>I am using G.711 codec, frame_size 80 and both 1024 and 2048 tail length. The code was compiled as floating point and fixed point in the PC. But none<br>of them help. I made sure the the synchronization between echo_frame and input_frame was stable and the delay is consistant about 10ms. The echo return loss<br>is around 20db but output_frame and input_frame signal is about the same. I even tried Jean-Marc's latest mdf.c from the subversion but no luck. <br><br>Has anyone test the performance in any other softphones and how well does it work? I have the recording files, anyone would be interesting in taking a look? <br>I wonder if there is something wrong with my input, setup...<br><br>BTW: did anyone ever try to port the algorithm to hardware? I will do some profiling and implement the most compuation expensive function in the Xilinx FPGA.<br>I would really appecriate if anyone can share some experience or provide adavise and suggest! I like to contribute my work to the Speex project if my <br>project turns out to be good end. <br><br>Regards,<br>William<br></div><br /><hr />Connect to the next generation of MSN Messenger <a href='http://imagine-msn.com/messenger/launch80/default.aspx?locale=en-us&source=wlmailtagline' target='_new'>Get it now!</a></body>
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