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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Version = speex1.2beta1<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I&#8217;ll try to recreate this in my
testbed and send back results, with maybe a code snippet. <o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> David Hogan
[mailto:david.hogan@freshtel.net] <br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, February 14, 2007
4:36 PM<br>
<b><span style='font-weight:bold'>To:</span></b> Chris Cowden;
speex-dev@xiph.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> RE: [Speex-dev] frame of
silence</span></font><o:p></o:p></p>

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

<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>In what fashion&nbsp;does&nbsp;the encoder
'blowup' when passed a frame of zeroes to encode?</span></font><o:p></o:p></p>

<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>What version of speex are you using?</span></font><o:p></o:p></p>

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

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

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<p class=MsoNormal style='margin-bottom:12.0pt'><b><font size=2 face=Tahoma><span
style='font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</span></font></b><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> Chris
Cowden [mailto:ccowden@ncsoft.com] <br>
<b><span style='font-weight:bold'>Sent:</span></b> Thursday, 15 February 2007
7:57 AM<br>
<b><span style='font-weight:bold'>To:</span></b> David Hogan;
speex-dev@xiph.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> RE: [Speex-dev] frame of
silence</span></font><o:p></o:p></p>

<blockquote style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt;
margin-left:3.75pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Okay, you&#8217;ve answered part of my
question, which is &#8220;What value equals silence?&#8221;. I assume then that
a (decoded) frame of silence would be a buffer the size of my frame (320 bytes)
full of 0&#8217;s.<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Passing this frame (a frame of all
0&#8217;s) through the encoder causes it to blowup though.. <o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>In response to your answer below, I
don&#8217;t think I want to overwrite the decoded audio output since I
don&#8217;t want to lose any &#8220;voice&#8221;, I only want to interpolate
silence into it. So I would guess your response to this would be &#8220;Why
don&#8217;t you just interpolate a frame of 0&#8217;s in between frames of
voice after it&#8217;s been decoded?&#8221;&#8230; to which I reply,
&#8220;that seems sort of hack-ish&#8230; I&#8217;m looking for a more
programmatic way of generating silence that the speex codec won&#8217;t choke
on.&#8221; Is there such a thing?<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I don&#8217;t mean to have a one-sided
conversation, only to make the best use of the bandwidth of this email.. Thank
you for your help and I look forward to any responses!<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p>&nbsp;</o:p></span></font></p>

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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> David Hogan
[mailto:david.hogan@freshtel.net] <br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, February 14, 2007
2:37 PM<br>
<b><span style='font-weight:bold'>To:</span></b> Chris Cowden; speex-dev@xiph.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> RE: [Speex-dev] frame of
silence</span></font><o:p></o:p></p>

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

<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>Forgive me if I misunderstood your
question, but can't you just overwrite the decoded audio buffer (either before
encoding or after decoding, depending on what you are trying to do) with zeros?</span></font><o:p></o:p></p>

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

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

<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>David Hogan</span></font><o:p></o:p></p>

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margin-left:3.75pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'>

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

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

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<p class=MsoNormal style='margin-bottom:12.0pt'><b><font size=2 face=Tahoma><span
style='font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</span></font></b><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
speex-dev-bounces@xiph.org [mailto:speex-dev-bounces@xiph.org] <b><span
style='font-weight:bold'>On Behalf Of </span></b>Chris Cowden<br>
<b><span style='font-weight:bold'>Sent:</span></b> Thursday, 15 February 2007
3:43 AM<br>
<b><span style='font-weight:bold'>To:</span></b> speex-dev@xiph.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> [Speex-dev] frame of
silence</span></font><o:p></o:p></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi, I&#8217;m new to this list. I&#8217;m using Speex as the
base codec in a voice chat application (with DirectSound as the audio
playback/capture interface).<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>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>To help me debug some of my network-related issues, I would
really like to insert frames of &#8220;silence&#8221; into speech. Is there a
convenient function call or API call that takes in a buffer that is the size of
a frame and writes a frame of &#8220;silence&#8221; to it?<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>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I&#8217;m not sure if I&#8217;m wording the question well,
so any feedback would be greatly appreciated!<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>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Btw, I am really enjoying using this codec and look forward
to getting this working! Thanks!<o:p></o:p></span></font></p>

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