Wireshark-dev: [Wireshark-dev] Jitter Buffer in Wireshark
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From: Krzysztof Cabaj <kcabaj@xxxxxxxxx>
Date: Thu, 10 Dec 2009 22:52:53 +0100
Hi,

Due to my research concerning jitter buffer, I tried to use Wireshark
to evaluate a number of packets dropped by buffer. However, there is
no description of jitter buffer implementation in Wireshark.
Therefore, I have verified source codes for version 1.2.4. I analyzed
file gtk/rtp_player.c and function decode_rtp_stream.

And, I have few concerns.

There is no real buffer, but only a number representing hypothetical
buffer size (variable jitter_buffer).
Packets are “dropped” when variable diff is greater than jitter_buffer
(line 758).
Variable diff represents absolute value in ms between real time of
receiving this packet and time when this packet should be
received (line 742).

I would be very grateful if somebody who know this part of code could
confirm these?

Regards,
Krzysztof Cabaj