RFC 3625 · INFORMATIONAL · 2003

The QCP File Format and Media Types for Speech Data

Overview

RFC 3625, “The QCP File Format and Media Types for Speech Data”, is an Informational document published in October 2003 by R. Gellens, H. Garudadri. It updates RFC 3555. The canonical text is published by the RFC Editor.

Abstract

RFC 2658 specifies the streaming format for 3GPP2 13KK 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.

Abstract as published in the RFC, via rfc-editor.org.

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

Read this RFC

The canonical text of RFC 3625 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC updates
RFC 3555
Other RFCs from 2003

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