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Hello I'm newbie here. I need to know about RTP payload type. I've got dynamic RTP payload type on my wireshark when I did video call using yahoo messenger.

Then it appears many RTP protocols and the info shows: PT=DynamicRTP-Type-123 and also PT=DynamicRTP-Type-97

Since it dynamic payload type, how could I know which RTP protocol carries video packets and which carries voice packets? CMIIW Thanks in advance :)

asked 23 May '13, 08:20

sekar's gravatar image

accept rate: 0%

You need to see the setup of the RTP where the codec is "assigned" a payload type, or possibly guess from the RTP packets. Video should transfer much more data. But you still ned the setup info to know which codec is beeing used it is quite possible proprietarry codecs are beeing used.

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answered 23 May '13, 08:25

Anders's gravatar image

Anders ♦
accept rate: 17%

well, thanks anders. 1. Yes I notice that payloadtype-123 are much more than type-97. I think that my video (which is motion-JPEG) was fragmented into packets since it has same timestamp. Am I right?

  1. Where could I find 'setup info'? Because I've read sooo much articles and I found that dynamic payload type 96-127 are unassigned.

  2. Does it possible for me to replay the audio from my video call?

Soorryy for asking too much. Need your help :)

(26 May '13, 07:58) sekar

Hi, I hvae no idea how yahoo Messenger works or what protocols it uses to set up video calls. In SIP SDP is used to describe the media session beeing set up if you look at the packets around the time of the actual setup of the call can anything be sen there(in plain text)? Without knowing what protocols and codecs Yahoo Messenger uses it will be very hard to do what you want.

(26 May '13, 12:49) Anders ♦
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question asked: 23 May '13, 08:20

question was seen: 13,974 times

last updated: 26 May '13, 12:49

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