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Re: [AVT] RTP/RTCP Timestamp and transmission time

Colin Perkins <csp@csperkins.org> Sat, 20 September 2003 15:26 UTC

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Date: Sat, 20 Sep 2003 00:30:58 +0100
Subject: Re: [AVT] RTP/RTCP Timestamp and transmission time
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To: Lorenzo Polidori <lorenzo@blt.it>
From: Colin Perkins <csp@csperkins.org>
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On Friday, Sep 19, 2003, at 08:36 Europe/London, Lorenzo Polidori wrote:

> At 12.56 18/09/2003 +0100, Colin Perkins wrote:
>
>> You need to schedule the transmission time of the RTP packets 
>> according
>> to their RTP timestamp. Since the packets are timed, there is a
>> correlation with the wall-clock.
>
> Ok, now it's clear, thanks all. But I have an other question. I must
> schedule  the transmission time of the RTP packets and the packets
> containing the same MPEG2 picture have the same RTP TS, since the time
> reference of the slides belonging to the same picture does not change. 
> Am I
> obliged to send a burst of RTP data packets every MPEG2 scheduled 
> picture,
> containing all the relative slides?

You are not obliged to send them in a burst, however RTP provides no 
way for the receiver to distinguish sender-induced delay from 
network-induced delay.

-- 
Colin Perkins
http://csperkins.org/


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