I recently had a scenario where I had to encode and decode RTP packets off the wire.

I wrote a Python Library to handle it which I’ve published for anyone to use.

Encoding data is quite simple, it takes a dictionary of values to fill the headers and payload and returns hex data to be sent down the wire:

payload = 'd5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5' 

packet_vars = {'version' : 2, 'padding' : 0, 'extension' : 0, 'csi_count' : 0, 'marker' : 0, 'payload_type' : 8, 'sequence_number' : 306, 'timestamp' : 306, 'ssrc' : 185755418, payload' : payload} 

PyRTP.GenerateRTPpacket(packet_vars)             #Generates hex to send down the wire 

And decoding is the same but reverse, feed it hex data and it returns a dict of values:

packet_bytes = '8008d4340000303c0b12671ad5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5d5'

rtp_params = PyRTP.DecodeRTPpacket(packet_bytes) #Returns dict of values from packet

Hopefully it’ll save someone else some time in the future.

For more info on RTP see:

RTP – More than you Wanted to Know for a deep dive into the packet structure