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hi. i have a pcap with RTP packets. in this pcap i have no SIP or SDP packets(only RTP).and payload type field is dynamic. How can i find out payload type? ALL payloads start with 0x000001B2? and marker bit is set in all packets. are these packets containing MPEG? i know that payloa_type=32 has been assigned to MPEG. but is it possible that these packets are MPEG?

asked 15 Jul '17, 11:58

hhw's gravatar image

accept rate: 100%

edited 15 Jul '17, 12:12

grahamb's gravatar image

grahamb ♦

If you have just the RTP stream with no SDP describing it, you can guess about media type (audio, video, image) and codec only by bandwidth, regularity of packet timing and size, and the contents of the payload.

Other than that, are you sure the 0x000001b2 is part of the payload, can't it be the SSRC which directly precedes it?

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answered 15 Jul '17, 12:16

sindy's gravatar image

accept rate: 24%

edited 15 Jul '17, 12:28

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question asked: 15 Jul '17, 11:58

question was seen: 1,913 times

last updated: 15 Jul '17, 12:36

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