The QCP File Format and Media Types for Speech Data
RFC 3625
Document | Type |
RFC - Informational
(October 2003; Errata)
Updates RFC 3555
Was draft-gellens-qcp (gen)
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Authors | Harinath Garudadri , Randall Gellens | ||
Last updated | 2020-01-21 | ||
Stream | ISE | ||
Formats | plain text html pdf htmlized with errata bibtex | ||
Stream | ISE state | (None) | |
Consensus Boilerplate | Unknown | ||
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 3625 (Informational) | |
Telechat date | |||
Responsible AD | Allison Mankin | ||
IESG note | This documents a storage format for QCELP audio - it is time-sensitive to 3GPP2, which needs it for the streaming applications of the EVRC and SMV vocoders. It was discussed by the AVT Working Group, which published its own storage format for data from those vocoders, but agreed this one, with a distinct name, was equally publishable. | ||
Send notices to | (None) |
Network Working Group R. Gellens Request for Comments: 3625 H. Garudadri Updates: 3555 Qualcomm Category: Informational September 2003 The QCP File Format and Media Types for Speech Data Status of this Memo This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2003). All Rights Reserved. Abstract RFC 2658 specifies the streaming format for 3GPP2 13K vocoder (High Rate Speech Service Option 17 for Wideband Spread Spectrum Communications Systems, also known as QCELP 13K vocoder) data, but does not specify a storage format. Many implementations have been using the "QCP" file format (named for its file extension) for exchanging QCELP 13K data as well as Enhanced Variable Rate Coder (EVRC) and Selectable Mode Vocoders (SMV) data. (For example, Eudora(r), QuickTime(r), and cmda2000(r) handsets). This document specifies the QCP file format and updates the audio/qcelp media registration to specify this format for storage, and registers the audio/evrc-qcp and audio/smv-qcp media types for EVRC and SMV (respectively) data stored in this format. Gellens & Garudadri Informational [Page 1] RFC 3625 QCP File Format and Media Types September 2003 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions Used in this Document. . . . . . . . . . . . . . . 2 3. QCP File Format. . . . . . . . . . . . . . . . . . . . . . . . 2 4. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 10 4.1. Update of Media Type Audio/qcelp . . . . . . . . . . . . 10 4.2. Update of Media Type Audio/vnd.qcelp . . . . . . . . . . 10 4.3. Registration of Audio/EVRC-QCP . . . . . . . . . . . . . 11 4.4. Registration of Audio/SMV-QCP. . . . . . . . . . . . . . 12 5. Security Considerations. . . . . . . . . . . . . . . . . . . . 13 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7.1. Normative References . . . . . . . . . . . . . . . . . . 13 7.2. Informative References . . . . . . . . . . . . . . . . . 13 8. Intellectual Property Statement. . . . . . . . . . . . . . . . 14 9. Editors' Addresses . . . . . . . . . . . . . . . . . . . . . . 14 10. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 15 1. Introduction This document specifies the QCP format for storage of [QCELP] 13K, [EVRC], and [SMV] vocoder frames in files which may reside on network elements (e.g., media servers, Multimedia Messaging System (MMS) centers, etc.) and third-generation cellular (3G) handsets, or be transmitted via email or other mechanisms. Vocoder frames read from a QCP file may be streamed using protocols and formats outside the scope of this document, delivered to an [EVRC], [SMV], or [QCELP] 13K decoder, or otherwise processed. The QCP format supports [QCELP] 13K as well as [EVRC] and [SMV] data. Note that this format is different from the EVRC and SMV storage format specified in [EVRC-SMV]. 2. Conventions Used in this Document The key words "REQUIRED", "MUST", "MUST NOT", "SHOULD", "SHOULD NOT", and "MAY" in this document are to be interpreted as described in BCP 14, RFC 2119 [KEYWORDS]. 3. QCP File Format The following describes the QCP file format using [ABNF]. A qcp file contains data frames generated by the [QCELP], [EVRC], or [SMV] vocoders. Gellens & Garudadri Informational [Page 2] RFC 3625 QCP File Format and Media Types September 2003 qcp-file = riff-qlcm fmt vrat [labl] [offs] data [cnfg] [text] riff-qlcm = RIFF riff-size QLCM fmt = FMT chunk-size major minor codec-info ; major and minor are set to the version of ; the QCP file format used to generate the ; file - currently, the following versions ; are defined: ; ; major = 2, minor = 0 ; used for SMV. ; major = 1, minor = 0 ; used for QCELP-13K and EVRC vrat = VRAT chunk-size var-rate-flag size-in-packets labl = LABL chunk-size label offs = OFFS chunk-size step-size num-offsets *offset ; number of repetitions of offset must equal ; num-offsets data = DATA chunk-size *packet [pad]Show full document text