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I'm completely new to video/audio formats, containers, and protocols. However, I have to figure out how to decode a bitstream that contains audio and video. I do not know the transport protocol, container format, or codecs used -- but I have been able to deduce a few things:

  • It's not RTP
  • It's over UDP on port 443
  • Audio and video are in datagrams
  • audio datagram payloads are always 76 bytes in length, and there are about 42 of them a second.
  • video datagram payloads are a maximum of 536 bytes, average is around 500 bytes, and there are about 62 of them a second.

How should I even begin to try to decode it?

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migrated from Jan 24 '14 at 12:01

This question came from our site for engineers, producers, editors, and enthusiasts spanning the fields of video, and media creation.

Did you try decoding it with ffmpeg? It supports UDP as input. – LordNeckbeard Jul 13 '12 at 20:51

Capture a chunk in Wireshark and then chose "decode as" and keep picking different A/V formats and see if any of them work. If none of that helps, upload a 100 kbyte wireshark pcap file and link to it here and I'll take a look.

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