RTP AAC Packet Depacketizer

Question

I asked earlier about H264 at RTP H.264 Packet Depacketizer

My question now is about the audio packets.

I noticed via the RTP packets that audio frames like AAC, G.711, G.726 and others all have the Marker Bit set.

I think frames are independent. am I right?

My question is: Audio is small, but I know that I can have more than one frame per RTP ​​packet. Independent of how many frames I have, they are complete? Or it may be fragmented between RTP packets.

Answer 1

The difference between audio and video is that audio is typically encoded either in individual samples, or in certain [small] frames without reference to previous data. Additionally, amount of data is small. So audio does not typically need complicated fragmentation to be transmitted over RTP. However, for any payload type you should again refer to RFC that describes the details:

• AAC - RTP Payload Format for MPEG-4 Audio/Visual Streams
• G.711 - RTP Payload Format for ITU-T Recommendation G.711.1
• G.726 - RTP Profile for Audio and Video Conferences with Minimal Control
• Other