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<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=EN-US
style='font-size:10.0pt;font-family:Arial;color:blue'>Dear Xiaoming Zhou,</span></font><span
lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>&nbsp;<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=EN-US
style='font-size:10.0pt;font-family:Arial;color:blue'>you can calculate the Ie
values from MOS values using the procedure given in ITU P.830 and P.833:</span></font><span
lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=EN-US
style='font-size:10.0pt;font-family:Arial;color:blue'>1. iLBC MOS values for
different packet loss rates are available from GlobalIPsound or </span></font><span
lang=EN-US><a href="http://www.ilbcfreeware.org/"><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>http://www.ilbcfreeware.org/</span></font></a></span><font
size=2 color=blue face=Arial><span lang=EN-US style='font-size:10.0pt;
font-family:Arial;color:blue'>. </span></font><span lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=EN-US
style='font-size:10.0pt;font-family:Arial;color:blue'>2.
Use&nbsp;the&nbsp;conversation&nbsp;formular&nbsp;given&nbsp;in&nbsp;ITU&nbsp;G.107&nbsp;or&nbsp;in
</span></font><span lang=EN-US><a
href="http://www.tkn.tu-berlin.de/publications/papers/MOS_R2.pdf"><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>http://www.tkn.tu-berlin.de/publications/papers/MOS_R2.pdf</span></font></a></span><font
size=2 color=blue face=Arial><span lang=EN-US style='font-size:10.0pt;
font-family:Arial;color:blue'>&nbsp;to&nbsp;calculate&nbsp;the&nbsp;R&nbsp;factor.&nbsp;</span></font><span
lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=EN-US
style='font-size:10.0pt;font-family:Arial;color:blue'>3. Subtract&nbsp;the&nbsp;R
factors from the
R0&nbsp;value&nbsp;(93.2)&nbsp;to&nbsp;get&nbsp;the&nbsp;Id&nbsp;values.</span></font><span
lang=EN-US><o:p></o:p></span></p>

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<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>&nbsp;<o:p></o:p></span></font></p>

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<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=EN-US
style='font-size:10.0pt;font-family:Arial;color:blue'>Best regards,</span></font><span
lang=EN-US><o:p></o:p></span></p>

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<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>&nbsp;<o:p></o:p></span></font></p>

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<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=EN-US
style='font-size:10.0pt;font-family:Arial;color:blue'>&nbsp;Christian Hoene</span></font><span
lang=EN-US><o:p></o:p></span></p>

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<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>&nbsp;<o:p></o:p></span></font></p>

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<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'><o:p>&nbsp;</o:p></span></font></p>

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face="Times New Roman"><span lang=EN-US style='font-size:12.0pt'>

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<p class=MsoNormal style='margin-bottom:12.0pt'><b><font size=2 face=Tahoma><span
lang=EN-US style='font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</span></font></b><font
size=2 face=Tahoma><span lang=EN-US style='font-size:10.0pt;font-family:Tahoma'>
end2end-interest-bounces@postel.org
[mailto:end2end-interest-bounces@postel.org] <b><span style='font-weight:bold'>On
Behalf Of </span></b>X.Zhou@ewi.tudelft.nl<br>
<b><span style='font-weight:bold'>Sent:</span></b> Donnerstag, 22. September
2005 10:05<br>
<b><span style='font-weight:bold'>To:</span></b> end2end-interest@postel.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> [e2e] question about the
iLBC (VoIP)</span></font><span lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>To examine the quality of VoIP, E-Model is often
used. The output of the E-model is a transmission ration factor R:
R=R0-Is-Id-Ie+A, where R0 represents the basic signal-to-noise ration, Is
represents the impairments occurring simultaneously with the voice signal, Id
represents the impairments caused by delay, and Ie represents the impairments
caused by codecs. </span></font><span lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>Is there any publication gives the Ie value for the codec
iLBC?</span></font><span lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>&nbsp;<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>Regards,</span></font><span lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>Xiaoming Zhou</span></font><span lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>&nbsp;<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>&nbsp;<o:p></o:p></span></font></p>

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