Subject: [AVT] 27MHz time stamp for MP2T

From: szhu <[email-masked]>
Date: Fri, 02 Aug 2002 13:56:56 -0700

Hi,

The current RTP time stamp resolution is 90K Hz for MP2T format. Some
people here have raised an issue that to handle MPTS and VBR, to have a
more precise time stamp, a dynamic payload format can be defined, which
should carry a 27M Hz timestamp. The 27M Hz time stamp will have the
same precision as that of the PCR in MPEG2 Transport Stream (MP2T). This
is for the IP dejittering purpose. May I have some expert's opinion on
this idea?

Thank you,
Shan Zhu

_______________________________________________
Audio/Video Transport Working Group
[email-masked]
https://www1.ietf.org/mailman/listinfo/avt

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From: Colin Perkins <[email-masked]>
Date: Mon, 05 Aug 2002 16:40:30 -0400

>is for the IP dejittering purpose. May I have some expert's opinion on

This has been discussed previously in AVT, with the general conclusion that
it's a good idea (e.g. see the discussion on an "Update to RFC 2250" in the
AVT minutes from the London IETF meeting). You may wish to coordinate with
Reha Civanlar on the update to RFC 2250.

Colin

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From: "M. Reha Civanlar" <[email-masked]>
Date: Tue, 06 Aug 2002 12:39:21 -0400

It seems like this is the only modification on RFC 2250 in which the WG has
shown some interest since I listed a collection of suggestions in the 51st
meeting.

Considering this and the large number of existing implementations of RFC
2250, instead of updating it, I suggest preparing another short RFC to
define a new payload type which uses the MP2T payload format from RFC 2250,
but allows for out-of-band definition of the clock frequency.

Any comments?

M. Reha Civanlar
[email-masked]