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<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>Hi all:<o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='text-align:left'><font size=3
face="Times New Roman"><span lang=EN-US style='font-size:12.0pt'> I
am reading the source code of the live555 now. What puzzles me a lot is the background
principle of the live555. Take testMPEG4VideoStreamer.cpp as an example:<o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='margin-left:21.0pt;mso-para-margin-left:
2.0gd;text-align:left'><font size=3 face="Times New Roman"><span lang=EN-US
style='font-size:12.0pt'>I traced the program by inserting printf statement in
some function and saw the below information<o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='margin-left:21.0pt;mso-para-margin-left:
2.0gd;text-align:left'><font size=4 face="Times New Roman"><span lang=EN-US
style='font-size:14.0pt'>play()-><o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='margin-left:21.0pt;mso-para-margin-left:
2.0gd;text-align:left'><font size=4 face="Times New Roman"><span lang=EN-US
style='font-size:14.0pt'>RTPSink::startPlaying-><o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='margin-left:21.0pt;mso-para-margin-left:
2.0gd;text-align:left'><font size=4 face="Times New Roman"><span lang=EN-US
style='font-size:14.0pt'>MultiFramedRTPSink::continuePlaying-><o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='margin-left:21.0pt;mso-para-margin-left:
2.0gd;text-align:left'><font size=4 face="Times New Roman"><span lang=EN-US
style='font-size:14.0pt'>MultiFramedRTPSink::buildAndSendPacket-><o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='margin-left:21.0pt;mso-para-margin-left:
2.0gd;text-align:left'><font size=4 face="Times New Roman"><span lang=EN-US
style='font-size:14.0pt'>MultiFramedRTPSink::packFrame-><o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='margin-left:21.0pt;mso-para-margin-left:
2.0gd;text-align:left'><font size=4 face="Times New Roman"><span lang=EN-US
style='font-size:14.0pt'>FramedSource::getNextFrame-><o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='margin-left:21.0pt;mso-para-margin-left:
2.0gd;text-align:left'><font size=4 face="Times New Roman"><span lang=EN-US
style='font-size:14.0pt'>MPEGVideoStreamFramer::doGetNextFramer-></span></font><font
size=4><span lang=EN-US style='font-size:14.0pt'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:21.0pt'><font size=4
face="Times New Roman"><span lang=EN-US style='font-size:14.0pt'>ByteStreamFileSource::doGetNextFrame</span></font><span
lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-indent:21.0pt'><font
size=3 face="Times New Roman"><span lang=EN-US style='font-size:12.0pt'>That’s
it. I don’t know why </span></font><font size=4><span lang=EN-US
style='font-size:14.0pt'>ByteStreamFileSource::doGetNextFrame</span></font><font
size=3><span lang=EN-US style='font-size:12.0pt'> appears here suddenly. Who
calls it? I guess there may be some background jobs. As I can not find any code
about this calling, I am not sure about that.<o:p></o:p></span></font></p>
<p class=MsoNormal align=left style='text-align:left;text-indent:21.0pt'><font
size=2 face="Times New Roman"><span lang=EN-US style='font-size:10.5pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal align=left style='text-align:left;text-indent:21.0pt'><font
size=3 face="Times New Roman"><span lang=EN-US style='font-size:12.0pt'>Any
help<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:21.0pt'><font size=3
face="Times New Roman"><span lang=EN-US style='font-size:12.0pt'>Thank you<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span lang=EN-US
style='font-size:10.5pt'><o:p> </o:p></span></font></p>
<p class=MsoAutoSig><font size=4 face="Times New Roman"><span lang=EN-US
style='font-size:14.0pt'>Best </span></font><font size=4><span lang=EN-US
style='font-size:14.0pt'>Regards<o:p></o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face="Times New Roman"><span lang=EN-US><o:p> </o:p></span></font></p>
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