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Re: [AVT] Update (-09) of Timed Tex draft (WAS: RE: Comments ondraft-ietf-avt-rtp-3gpp-timed-text-08.txt)
Rey Jose wrote:
Option two is not addressing the concerns of Colin, namely non-standard RTP handling, because the TYPE 5 TS would not be visible until you extract the packet from buffer, sometimes too late, so that is not a solution. If we are going for this line, easier would be to keep the solution as is now.
Yes, not putting the earliest timestamp in the RTP header will prevent
any entity pre-depacketization to determine from when the SDs can be
used. Assuming that we avoid this and go with a TYPE 5 packet that has a
TS offset field (32 bits). Then we need to add text that the jitter
calculation becomes basically useless if one sends dynamic SDs that are
repeated. This due to the periodically jump in the TS backwards when one
includes the repeated SDs. I would also recommend that the TS offset
field is not called SDUR, because this is not the sample duration, it is
only a TS offset to the next unit.
Cheers
Magnus Westerlund
Multimedia Technologies, Ericsson Research EAB/TVA/A
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Ericsson AB | Phone +46 8 4048287
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S-164 80 Stockholm, Sweden | mailto: magnus.westerlund at ericsson.com
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