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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'>More info:<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> </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 tried disabling the “zero floor”
optimization on the encoding side – specifically, in the function
floor1_fit, I replaced “if(nonzero)” with “if(1)”. This
seems to have fixed the problem. Does this help explain anything? Is this a
safe change to make? Is there something better I can do to get the same
effect?<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> </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'>-Ethan<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> </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'>
vorbis-dev-bounces@xiph.org [mailto:vorbis-dev-bounces@xiph.org] <b><span
style='font-weight:bold'>On Behalf Of </span></b>Ethan Fenn<br>
<b><span style='font-weight:bold'>Sent:</span></b> Thursday, December 29, 2005
6:48 PM<br>
<b><span style='font-weight:bold'>To:</span></b> vorbis-dev@xiph.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> [Vorbis-dev] artifacting
with many channels</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> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi all,<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> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am using oggenc to compress multichannel audio streams
(4-10 channels) and am having some severe artifacting on decode. What
seems to be happening is that at times when one channel is silent, one or more
of the other channels will be badly mangled. Simply reordering the
channels seems to fix the problem sometimes, but not predictably. It also
seems to be independent of quality used (it happens equally with quality=-1 and
quality=10).<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> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Does anyone have any idea what could cause this, and what I
might be able to do to fix 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> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>-Ethan<o:p></o:p></span></font></p>
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