[Live-devel] Is there a RTP payload type for a MPEG program stream?

[Ross Finlayson]

At 11:48 AM 7/23/04, you wrote:
>Section 1 and 2 of RFC 2250 (RTP payload type for MPEG1/2 Video) mention 
>that MPEG1 system streams and MPEG2 program streams may be carried in RTP 
>packets.  Section 2.1 says that distinct types are given in the RTP header 
>for MPEG1 System streams, MPEG2 program streams, and MPEG2 transport 
>streams and it references RFC 1890 for those payload type 
>assignments.  But nowhere in RFC 1890 does it mention MPEG1 system or 
>MPEG2 program streams, only the MPEG2 transport stream (and the ES 
>stream).  Am I confused?  Can RTP carry a MPEG program stream?

(First, note that general questions about RTP payload formats - independent 
of the "LIVE.COM Streaming Media" software - are best addressed to the 
"avt at ietf.org" mailing list.)

(Also, BTW, RFC 1890 has now been superceded by RFC 3551.)

Yes, MPEG System and Program streams can be sent via RTP, as defined in RFC 
2250.  However, unlike MPEG Transport Streams and MPEG (1 or 2) Elementary 
Streams, there are no *static* payload type numbers defined for 
these.  That's why they're not mentioned in RFC 1890 or 3551.  Instead, 
they are required to use dynamic payload type numbers.  (Note also, FYI, 
the MIME types "video/MP1S" and "video/MP2P" defined in RFC 3555.)


	Ross Finlayson
	LIVE.COM
	<http://www.live.com/>