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<DIV><SPAN class=214485105-07082008><FONT face=Verdana><SPAN
class=812032610-07082008>Hi all,</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=214485105-07082008><FONT face=Verdana><SPAN
class=812032610-07082008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=214485105-07082008><FONT face=Verdana><SPAN
class=812032610-07082008></SPAN>I'm trying to figure out how to calculate the
RTPTime values in the RTSP/PLAY-Response "RTP-Info" header, based on an incoming
live RTP/RTCP stream(s) from a live encoder.</FONT></SPAN></DIV>
<DIV><FONT face=Verdana><SPAN
class=214485105-07082008></SPAN></FONT> </DIV>
<DIV><SPAN class=214485105-07082008><FONT face=Verdana>I've pulled apart an
HUSM <SPAN class=812032610-07082008>packet </SPAN>dump and the critical
section looks something like this:</FONT></SPAN></DIV>
<DIV><SPAN class=214485105-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=214485105-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=214485105-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=214485105-07082008>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana>769: RTCP-SR/9301 from
LENC</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana> NTP:
MSW: 3403825895 (0xcae242e7); LSW: 133143986 (0x07ef9db2) ==> Nov
12, 2007 03:11:35.0310 UTC</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana> RTP:
670943030</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana>803: RTCP-SR/9303 from
LENC</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana> NTP:
MSW: 3403825896 (0xcae242e8); LSW: 64424509 (0x03d70a3d) ==> Nov 12, 2007
03:11:36.0150 UTC<BR> RTP: 383790848</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana>840: RTCP-SR/9301 from
LENC</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana> NTP:
MSW: 3403825897 (0xcae242e9); LSW: 64424509 (0x03d70a3d) ==> Nov 12, 2007
03:11:37.0150 UTC<BR> RTP: 671123120</FONT></SPAN></DIV>
<DIV><FONT face=Verdana></FONT> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana color=#ff0000>871:
RTSP/PLAY-Request from CLIENT</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana>881: RTCP-SR/9303 from
LENC</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT
face=Verdana> NTP: MSW: 3403825898 (0xcae242ea); LSW:
64424509 (0x03d70a3d) ==> Nov 12, 2007 03:11:38.0150 UTC</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana> RTP:
383834926</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana color=#ff0000>882:
RTCP-SR/3457 to CLIENT</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana> Same
as 881<BR><BR>906: RTCP-RR/3457 from CLIENT</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana>919: RTCP-SR/9301 from
LENC</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana> NTP:
MSW: 3403825899 (0xcae242eb); LSW: 133143986 (0x07ef9db2) ==> Nov 12, 2007
03:11:39.0310 UTC</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana> RTP:
671303570</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT
face=Verdana></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana color=#ff0000>920:
RTCP-SR/9301 to CLIENT</FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><SPAN class=510183102-07082008><FONT
face=Verdana> Same as 919</FONT></SPAN></SPAN></DIV>
<DIV><FONT face=Verdana><SPAN class=510183102-07082008><SPAN
class=510183102-07082008></SPAN></SPAN><SPAN class=510183102-07082008><SPAN
class=510183102-07082008> </DIV></SPAN></SPAN></FONT>
<DIV><SPAN class=510183102-07082008><SPAN class=510183102-07082008><FONT
face=Verdana>921: RTP/9302 from LENC</FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><SPAN class=510183102-07082008><FONT
face=Verdana> Seq: 39932</FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008> RTP:
383841717</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><SPAN class=510183102-07082008><FONT
face=Verdana color=#ff0000>922: RTP/3456 to CLIENT</FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><SPAN class=510183102-07082008><FONT
face=Verdana> Same as 921</FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><SPAN class=510183102-07082008><FONT
face=Verdana>923: RTP/9300 from LENC</FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008> Seq:
59095</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008> RTP:
671369087</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><SPAN class=510183102-07082008><FONT
face=Verdana>924: RTP/9302 from LENC</FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008> Seq:
39933</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008> RTP:
383842741</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana color=#ff0000><SPAN
class=510183102-07082008>925: RTSP/PLAY-Response to
CLIENT</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana><SPAN
class=510183102-07082008> RTP-Info:
url=rtsp://172.28.15.239/rtpencoder/<SPAN
class=214485105-07082008>Blah</SPAN>.sdp/streamid=1;seq=39932;rtptime=383841717,</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT size=+0><SPAN
class=510183102-07082008><FONT size=2><FONT face=Verdana><SPAN
class=214485105-07082008>
</SPAN>url=rtsp://172.28.15.239/rtpencoder/<SPAN
class=214485105-07082008>Blah</SPAN>.sdp/streamid=0;seq=59095;rtptime=671239890</FONT></FONT></SPAN></FONT></SPAN></DIV>
<DIV><FONT face=Verdana size=2></FONT> </DIV>
<DIV><SPAN class=510183102-07082008><FONT size=2><SPAN class=510183102-07082008>
<DIV><SPAN class=510183102-07082008><FONT size=2><SPAN
class=510183102-07082008><FONT face=Verdana color=#ff0000 size=2>926: RTP/3458
to CLIENT</FONT></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT size=2><SPAN
class=510183102-07082008></SPAN></FONT></SPAN><SPAN
class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008> Seq:
59095</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008> RTP:
671369087</SPAN></FONT></SPAN></DIV></SPAN></FONT></SPAN><SPAN
class=510183102-07082008><FONT size=2><SPAN class=510183102-07082008><FONT
size=2></FONT></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT size=2><SPAN
class=510183102-07082008><FONT face=Verdana
size=2></FONT></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><SPAN class=510183102-07082008>
<DIV><FONT size=2><FONT face=Verdana><SPAN class=510183102-07082008><SPAN
class=510183102-07082008>927: RTP/3456 to CLIENT<BR></SPAN></SPAN><SPAN
class=510183102-07082008><SPAN class=510183102-07082008> Seq:
39933</SPAN></SPAN></FONT></FONT></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008> RTP:
383842741</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008><SPAN class=214485105-07082008>How in the world did
HUSM come up with "rtptime=671239890"?????</SPAN></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008><SPAN
class=214485105-07082008></SPAN></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008><SPAN class=214485105-07082008>Is there any reference
or commonly cited material about how these values are
calculated?</SPAN></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008><SPAN
class=214485105-07082008></SPAN></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008><SPAN class=214485105-07082008>Thanks in
advance,</SPAN></SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008><SPAN
class=214485105-07082008></SPAN></SPAN></FONT></SPAN> </DIV>
<DIV><SPAN class=510183102-07082008><FONT face=Verdana size=2><SPAN
class=510183102-07082008><SPAN
class=214485105-07082008>ChrisB</SPAN></SPAN></FONT></SPAN></DIV></SPAN></SPAN></DIV></SPAN></DIV></FONT></DIV>
<DIV> </DIV>
<DIV class=Section1>
<P class=MsoNormal align=left><B style="mso-bidi-font-weight: normal"><SPAN
style="FONT-SIZE: 7.5pt; FONT-FAMILY: Verdana"><ST1:PERSONNAME w:st="on">Chris
Burns<BR></SPAN></B><SPAN style="FONT-SIZE: 7.5pt; FONT-FAMILY: Verdana">M: +64
21 391 286<BR></SPAN><SPAN style="FONT-SIZE: 7.5pt; FONT-FAMILY: Verdana"><A
href="mailto:chris.burns@abdeus.com">chris.burns@abdeus.com</A></SPAN></ST1:PERSONNAME></P></DIV></BODY></HTML>