Network Working Group J. van der Meer
Request for Comments: 3640 Philips Electronics
Category: Standards Track D. Mackie
Apple Computer
V. Swaminathan
Sun Microsystems Inc.
D. Singer
Apple Computer
P. Gentric
Philips Electronics
November 2003
RTP Payload Format for Transport of MPEG-4 Elementary Streams
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
The Motion Picture Experts Group (MPEG) Committee (ISO/IEC JTC1/SC29
WG11) is a working group in ISO that produced the MPEG-4 standard.
MPEG defines tools to compress content such as audio-visual
information into elementary streams. This specification defines a
simple, but generic RTP payload format for transport of any non-
multiplexed MPEG-4 elementary stream.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Carriage of MPEG-4 Elementary Streams Over RTP . . . . . . . . 4
2.1. Signaling by MIME Format Parameters . . . . . . . . . . 4
2.2. MPEG Access Units . . . . . . . . . . . . . . . . . . . 5
2.3. Concatenation of Access Units . . . . . . . . . . . . . 5
2.4. Fragmentation of Access Units . . . . . . . . . . . . . 6
2.5. Interleaving . . . . . . . . . . . . . . . . . . . . . . 6
2.6. Time Stamp Information . . . . . . . . . . . . . . . . . 7
2.7. State Indication of MPEG-4 System Streams . . . . . . . 8
2.8. Random Access Indication . . . . . . . . . . . . . . . . 8
van der Meer, et al. Standards Track [Page 1]
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