RTP Payload Format for the Opus Speech and Audio Codec
RFC 7587
Document | Type | RFC - Proposed Standard (June 2015; No errata) | |
---|---|---|---|
Authors | Julian Spittka , Koen Vos , Jean-Marc Valin | ||
Last updated | 2015-10-14 | ||
Replaces | draft-spittka-payload-rtp-opus | ||
Stream | Internet Engineering Task Force (IETF) | ||
Formats | plain text html pdf htmlized (tools) htmlized bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Ali Begen | ||
Shepherd write-up | Show (last changed 2015-01-13) | ||
IESG | IESG state | RFC 7587 (Proposed Standard) | |
Action Holders |
(None)
|
||
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Ben Campbell | ||
Send notices to | (None) | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) J. Spittka Request for Comments: 7587 Category: Standards Track K. Vos ISSN: 2070-1721 vocTone JM. Valin Mozilla June 2015 RTP Payload Format for the Opus Speech and Audio Codec Abstract This document defines the Real-time Transport Protocol (RTP) payload format for packetization of Opus-encoded speech and audio data necessary to integrate the codec in the most compatible way. It also provides an applicability statement for the use of Opus over RTP. Further, it describes media type registrations for the RTP payload format. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7587. Copyright Notice Copyright (c) 2015 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 Simplified BSD License. Spittka, et al. Standards Track [Page 1] RFC 7587 RTP Payload Format for Opus June 2015 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions, Definitions, and Acronyms Used in This Document 3 3. Opus Codec . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.1. Network Bandwidth . . . . . . . . . . . . . . . . . . . . 4 3.1.1. Recommended Bitrate . . . . . . . . . . . . . . . . . 4 3.1.2. Variable versus Constant Bitrate . . . . . . . . . . 4 3.1.3. Discontinuous Transmission (DTX) . . . . . . . . . . 5 3.2. Complexity . . . . . . . . . . . . . . . . . . . . . . . 6 3.3. Forward Error Correction (FEC) . . . . . . . . . . . . . 6 3.4. Stereo Operation . . . . . . . . . . . . . . . . . . . . 6 4. Opus RTP Payload Format . . . . . . . . . . . . . . . . . . . 7 4.1. RTP Header Usage . . . . . . . . . . . . . . . . . . . . 7 4.2. Payload Structure . . . . . . . . . . . . . . . . . . . . 7 5. Congestion Control . . . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 6.1. Opus Media Type Registration . . . . . . . . . . . . . . 9 7. SDP Considerations . . . . . . . . . . . . . . . . . . . . . 12 7.1. SDP Offer/Answer Considerations . . . . . . . . . . . . . 13 7.2. Declarative SDP Considerations for Opus . . . . . . . . . 15 8. Security Considerations . . . . . . . . . . . . . . . . . . . 15 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 16 9.1. Normative References . . . . . . . . . . . . . . . . . . 16 9.2. Informative References . . . . . . . . . . . . . . . . . 17 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 18 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 1. Introduction Opus [RFC6716] is a speech and audio codec developed within the IETF Internet Wideband Audio Codec working group. The codec has a very low algorithmic delay, and it is highly scalable in terms of audio bandwidth, bitrate, and complexity. Further, it provides different modes to efficiently encode speech signals as well as music signals, thus making it the codec of choice for various applications using the Internet or similar networks. This document defines the Real-time Transport Protocol (RTP) [RFC3550] payload format for packetization of Opus-encoded speech and audio data necessary to integrate Opus in the most compatible way. It also provides an applicability statement for the use of Opus over RTP. Further, it describes media type registrations for the RTPShow full document text