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I have a .pcap file after capturing voice packets. I now want to filter RTP packets (with header). When I select stream I am interested in and do "follow UDP stream" I get the udp payload (RTP including the header). But for all the packets captured there is no packet size. My application would want a 4 byte "packet length" before each packet. How can I get this fro wireshark.

Thanks for the help in advance.

asked 02 Aug '11, 09:23

shailesh's gravatar image

accept rate: 0%

There is no way to do that with "Follow UDP Stream" unless you change the source code and recompile Wireshark.

It might be easier to write a little script/program that uses the libpcap library to extract the UDP payload and save it with a length header in front of it. Then you can feed the individual RTP streams to it...

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answered 03 Aug '11, 01:25

SYN-bit's gravatar image

SYN-bit ♦♦
accept rate: 20%

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question asked: 02 Aug '11, 09:23

question was seen: 4,931 times

last updated: 03 Aug '11, 01:25

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