RFC 3640 (rfc3640) - Page 2 of 43


RTP Payload Format for Transport of MPEG-4 Elementary Streams



Alternative Format: Original Text Document



RFC 3640         Transport of MPEG-4 Elementary Streams    November 2003


       2.9.  Carriage of Auxiliary Information  . . . . . . . . . . .  8
       2.10. MIME Format Parameters and Configuring Conditional Field  8
       2.11. Global Structure of Payload Format . . . . . . . . . . .  9
       2.12. Modes to Transport MPEG-4 Streams  . . . . . . . . . . .  9
       2.13. Alignment with RFC 3016  . . . . . . . . . . . . . . . . 10
   3.  Payload Format . . . . . . . . . . . . . . . . . . . . . . . . 10
       3.1.  Usage of RTP Header Fields and RTCP  . . . . . . . . . . 10
       3.2.  RTP Payload Structure  . . . . . . . . . . . . . . . . . 11
             3.2.1.  The AU Header Section  . . . . . . . . . . . . . 11
                     3.2.1.1.  The AU-header  . . . . . . . . . . . . 12
             3.2.2.  The Auxiliary Section . . . . . . . . . . . . .  14
             3.2.3.  The Access Unit Data Section . . . . . . . . . . 15
                     3.2.3.1.  Fragmentation. . . . . . . . . . . . . 16
                     3.2.3.2.  Interleaving . . . . . . . . . . . . . 16
                     3.2.3.3.  Constraints for Interleaving . . . . . 17
                     3.2.3.4.  Crucial and Non-Crucial AUs with
                               MPEG-4 System Data . . . . . . . . . . 20
       3.3.  Usage of this Specification. . . . . . . . . . . . . . . 21
             3.3.1.  General. . . . . . . . . . . . . . . . . . . . . 21
             3.3.2.  The Generic Mode . . . . . . . . . . . . . . . . 22
             3.3.3.  Constant Bit Rate CELP . . . . . . . . . . . . . 22
             3.3.4.  Variable Bit Rate CELP . . . . . . . . . . . . . 23
             3.3.5.  Low Bit Rate AAC . . . . . . . . . . . . . . . . 24
             3.3.6.  High Bit Rate AAC. . . . . . . . . . . . . . . . 25
             3.3.7.  Additional Modes . . . . . . . . . . . . . . . . 26
   4.  IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 27
       4.1.  MIME Type Registration . . . . . . . . . . . . . . . . . 27
       4.2.  Registration of Mode Definitions with IANA . . . . . . . 33
       4.3.  Concatenation of Parameters. . . . . . . . . . . . . . . 33
       4.4.  Usage of SDP . . . . . . . . . . . . . . . . . . . . . . 34
             4.4.1.  The a=fmtp Keyword . . . . . . . . . . . . . . . 34
   5.  Security Considerations. . . . . . . . . . . . . . . . . . . . 34
   6.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 35
   APPENDIX: Usage of this Payload Format. . .  . . . . . . . . . . . 36
   Appendix A.  Interleave Analysis . . . . . . . . . . . . . . . . . 36
   A.  Examples of Delay Analysis with Interleave. . .  . . . . . . . 36
       A.1.  Introduction . . . . . . . . . . . . . . . . . . . . . . 36
       A.2.  De-interleaving and Error Concealment  . . . . . . . . . 36
       A.3.  Simple Group Interleave  . . . . . . . . . . . . . . . . 36
             A.3.1.  Introduction . . . . . . . . . . . . . . . . . . 36
             A.3.2.  Determining the De-interleave Buffer Size  . . . 37
             A.3.3.  Determining the Maximum Displacement . . . . . . 37
       A.4.  More Subtle Group Interleave . . . . . . . . . . . . . . 38
             A.4.1.  Introduction . . . . . . . . . . . . . . . . . . 38
             A.4.2.  Determining the De-interleave Buffer Size. . . . 38
             A.4.3.  Determining the Maximum Displacement . . . . . . 39
       A.5.  Continuous Interleave  . . . . . . . . . . . . . . . . . 39
             A.5.1.  Introduction . . . . . . . . . . . . . . . . . . 39



van der Meer, et al.        Standards Track