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<p class=MsoNormal><span style='font-size:12.0pt'>Hi Experts,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:12.0pt'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:12.0pt'>I am not sure if the live555
support redundant AMR frames in RTP streams. I don't see such code in the
live555 lib. So if the SDP contains </span><span style='font-size:12.0pt;
color:black'>max-red >0, how does the RTSP client react such RTP stream?<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:12.0pt;color:black'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:12.0pt;color:black'>Attach is the
description on max-red in SDP described in RFC4867, section 8:<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>max-red: The maximum duration in milliseconds
that elapses between<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
the primary (first) transmission of a frame and any<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
redundant transmission that the sender will use. </span><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>This<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>
</span><span style='font-size:12.0pt;font-family:Monaco;color:black'>parameter
allows a receiver to have a bounded delay when<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
</span><span lang=ZH-CN style='font-size:12.0pt;font-family:Monaco;color:black'>redundancy
is used. Allowed values are between 0 (no<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>
</span><span style='font-size:12.0pt;font-family:Monaco;color:black'>redundancy
will be used) and 65535. </span><span lang=ZH-CN style='font-size:12.0pt;
font-family:Monaco;color:black'>If the parameter is<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>
</span><span style='font-size:12.0pt;font-family:Monaco;color:black'>omitted,
no limitation on the use of redundancy is<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
</span><span lang=ZH-CN style='font-size:12.0pt;font-family:Monaco;color:black'>present.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:12.0pt'>and the example in section 3.7.1
figure 1:<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'> </span><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>--+--------+--------+--------+--------+--------+--------+--------+--<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>
| f(n-2) | f(n-1) | f(n) | f(n+1) | f(n+2) | f(n+3) | f(n+4) |<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>
--+--------+--------+--------+--------+--------+--------+--------+--<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>
</span><span style='font-size:12.0pt;font-family:Monaco;color:black'><----
p(n-1) ----><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
<----- p(n) -----><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
<---- p(n+1) ----><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
<---- p(n+2) ----><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
<---- p(n+3)
----><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:12.0pt;
font-family:Monaco;color:black'>
</span><span lang=ZH-CN style='font-size:12.0pt;font-family:Monaco;color:black'><----
p(n+4) ----><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span lang=ZH-CN
style='font-size:12.0pt;font-family:Monaco;color:black'>
</span><span style='font-size:12.0pt;font-family:Monaco;color:black'>Figure 1:
An example of redundant transmission<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:12.0pt'><o:p> </o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Arial Narrow","sans-serif";
color:navy'>Zhang, Changchun</span></b><b><span style='font-size:10.0pt;
font-family:"Arial Narrow","sans-serif";color:gray'> | NM | CDC |
Tektronix Communications | +86 21 38960464 | </span></b><b><u><span
style='font-size:10.0pt;font-family:"Arial Narrow","sans-serif";color:navy'>changchun.zhang</span></u></b><b><span
style='font-size:10.0pt;font-family:"Arial Narrow","sans-serif";color:gray'><a
href="mailto:zhang.changchun@tektronix.com"
title="mailto:keith.miller@tektronix.com"><span style='color:navy'>@tektronix.com</span></a></span></b><o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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