2022年6月16日 · Speex is an Open Source/Free Software patent-free audio compression format designed for speech. The Speex Project aims to lower the barrier of entry for voice applications by providing a free alternative to expensive proprietary speech codecs.

Speex 1.2.0. This is the latest stable release of the Speex codec library. Downloads: Speex Source Code; SpeexDSP 1.2rc3. This brown-paper-bag release adds two headers that should have been included with SpeexDSP 1.2rc2.

The Speex manual provides an introduction to Speex and CELP coding, speexenc and speexdec information, libspeex API information, and miscellaneous format information. PDF Postscript

Can Speex pass DTMF? Can Speex pass V.9x modem signals correctly? What is your (Jean-Marc) relationship with the University of Sherbrooke and how does Speex fit into that?

Speex modes have a query system similar to the speex_encoder_ctl and speex_decoder_ctl calls. Since modes are read-only, it is only possible to get information about a particular mode. The function used to do that is:

Chapter 5 Speex Module Documentation 5.1 Speex encoder and decoder Classes • struct SpeexMode Defines • #define SPEEX_SET_ENH 0 • #define SPEEX_GET_ENH 1

Speex Samples (based on version 1.2-beta1) Samples coded with Speex have been decoded back to wav format so you don't need to have a Speex decoder to listen to them. Narrowband. These samples are coded using narrowband Speex mode (more bit-rates available) Male. original; coded 4 kbps; coded 4 kbps VBR; coded 6 kbps; coded 8 kbps; coded 8 kbps ...

Speex is a lossy codec, which means that it achives compression at the expense of fidelity of the input speech signal. Unlike some other speech codecs, it is possible to control the tradeoff made between quality and bit-rate.

The base Speex distribution includes a command-line encoder (speexenc) and decoder (speexdec). This section describes how to use these tools. speexenc. The speexenc utility is used to create Speex files from raw PCM or wave files. It can be used by calling:

Speex wideband mode (sub-band CELP) For wideband, the Speex approach uses a q uadrature m irror f ilter (QMF) to split the band in two. The 16 kHz signal is thus divided into two 8 kHz signals, one representing the low band (0-4 kHz), the other the high band (4-8 kHz).