RTP Payload Format for Elementary Streams with MPEG Surround Multi-Channel Audio
RFC 5691
Document | Type |
RFC - Proposed Standard
(October 2009; No errata)
Updates RFC 3640
Was draft-ietf-avt-rtp-mps (avt WG)
|
|
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Authors | Stefan Doehla , Malte Schmidt , Frans de Bont , Ralph Sperschneider | ||
Last updated | 2015-10-14 | ||
Replaces | draft-schmidt-avt-mps | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 5691 (Proposed Standard) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Cullen Jennings | ||
Send notices to | (None) |
Network Working Group F. de Bont Request for Comments: 5691 Philips Electronics Updates: 3640 S. Doehla Category: Standards Track Fraunhofer IIS M. Schmidt Dolby Laboratories R. Sperschneider Fraunhofer IIS October 2009 RTP Payload Format for Elementary Streams with MPEG Surround Multi-Channel Audio Abstract This memo describes extensions for the RTP payload format defined in RFC 3640 for the transport of MPEG Surround multi-channel audio. Additional Media Type parameters are defined to signal backwards- compatible transmission inside an MPEG-4 Audio elementary stream. In addition, a layered transmission scheme that doesn't use the MPEG-4 systems framework is presented to transport an MPEG Surround elementary stream via RTP in parallel with an RTP stream containing the downmixed audio data. 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) 2009 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the BSD License. de Bont, et al. Standards Track [Page 1] RFC 5691 Transport of MPEG Surround October 2009 Table of Contents 1. Introduction ....................................................2 2. Conventions .....................................................3 3. Definitions and Abbreviations ...................................3 3.1. Definitions ................................................3 3.2. Abbreviations ..............................................4 4. Transport of MPEG Surround ......................................4 4.1. Embedded Spatial Audio Data in AAC Payloads ................4 4.2. MPEG Surround Elementary Stream ............................5 4.2.1. Low Bitrate MPEG Surround ...........................7 4.2.2. High Bitrate MPEG Surround ..........................8 5. IANA Considerations .............................................8 5.1. Media Type Registration ....................................9 5.2. Registration of Mode Definitions with IANA .................9 5.3. Usage of SDP ..............................................10 6. Security Considerations ........................................10 7. References .....................................................11 7.1. Normative References ......................................11 7.2. Informative References ....................................11 1. Introduction MPEG Surround (Spatial Audio Coding, SAC) [23003-1] is an International Standard that was finalized by MPEG in January 2007. It is capable of re-creating N channels based on M < N transmitted channels and additional control data. In the preferred modes of operating the Spatial Audio Coding system, the M channels can either be a single mono channel or a stereo channel pair. The control data represents a significantly lower data rate than the data rate required for transmitting all N channels, making the coding very efficient while at the same time ensuring compatibility with M channel devices. The MPEG Surround standard incorporates a number of tools that enable features that allow for broad application of the standard. A key feature is the ability to scale the spatial image quality gradually from very low spatial overhead towards transparency. Another key feature is that the decoder input can be made compatible to existing matrixed surround technologies. As an example, for 5.1 multi-channel audio, the MPEG Surround encoder creates a stereo (or mono) downmix signal and spatial informationShow full document text