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<DIV dir=ltr align=left><SPAN class=876012922-14022007><FONT face=Arial
color=#0000ff size=2>In what fashion does the encoder 'blowup' when
passed a frame of zeroes to encode?</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=876012922-14022007><FONT face=Arial
color=#0000ff size=2>What version of speex are you using?</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=876012922-14022007> </SPAN></DIV>
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<DIV dir=ltr align=left><FONT face=Tahoma size=2><B>From:</B> Chris Cowden
[mailto:ccowden@ncsoft.com] <BR><B>Sent:</B> Thursday, 15 February 2007 7:57
AM<BR><B>To:</B> David Hogan; speex-dev@xiph.org<BR><B>Subject:</B> RE:
[Speex-dev] frame of silence<BR></FONT><BR></DIV>
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<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">Okay, you’ve answered
part of my question, which is “What value equals silence?”. I assume then that
a (decoded) frame of silence would be a buffer the size of my frame (320
bytes) full of 0’s.<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">Passing this frame (a
frame of all 0’s) through the encoder causes it to blowup though..
<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">In response to your
answer below, I don’t think I want to overwrite the decoded audio output since
I don’t want to lose any “voice”, I only want to interpolate silence into it.
So I would guess your response to this would be “Why don’t you just
interpolate a frame of 0’s in between frames of voice after it’s been
decoded?”… to which I reply, “that seems sort of hack-ish… I’m looking for a
more programmatic way of generating silence that the speex codec won’t choke
on.” Is there such a thing?<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">I don’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 face=Arial color=navy size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
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<P class=MsoNormal><B><FONT face=Tahoma size=2><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT
face=Tahoma size=2><SPAN style="FONT-SIZE: 10pt; 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></DIV>
<P class=MsoNormal><FONT face="Times New Roman" size=3><SPAN
style="FONT-SIZE: 12pt"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">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 face="Times New Roman" size=3><SPAN
style="FONT-SIZE: 12pt"> <o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">Cheers,</SPAN></FONT><o:p></o:p></P>
<P class=MsoNormal><FONT face=Arial color=blue size=2><SPAN
style="FONT-SIZE: 10pt; COLOR: blue; FONT-FAMILY: Arial">David
Hogan</SPAN></FONT><o:p></o:p></P>
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<P class=MsoNormal><FONT face="Times New Roman" size=3><SPAN
style="FONT-SIZE: 12pt"><o:p> </o:p></SPAN></FONT></P>
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<P class=MsoNormal style="MARGIN-BOTTOM: 12pt"><B><FONT face=Tahoma
size=2><SPAN
style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT
face=Tahoma size=2><SPAN style="FONT-SIZE: 10pt; 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 face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Hi, I’m new to this list. I’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 face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">To help me debug some of my
network-related issues, I would really like to insert frames of “silence”
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 “silence” to
it?<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I’m not sure if I’m wording the
question well, so any feedback would be greatly
appreciated!<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; 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></BLOCKQUOTE></DIV></BLOCKQUOTE></BODY></HTML>