libg722

Introduction

The G.722 module is a bit exact implementation of the ITU G.722 specification for all three specified bit rates - 64000bps, 56000bps and 48000bps. It passes the ITU tests.

To allow fast and flexible interworking with narrow band telephony, the encoder and decoder support an option for the linear audio to be an 8k samples/second stream. In this mode the codec is considerably faster, and still fully compatible with wideband terminals using G.722.

History

The code was originally written by Milton Anderson [email protected] from BELLCORE, and has been modified by the Chengxiang Lu and Alex Hauptmann from the Speech Group, School of Computer Science, Carnegie Mellon University, to be fairly fast and efficient, while retaining high fidelity.

Steve Underwood [email protected] improved the code a lot later on and contributed it into several popular open source projects.

Himanshu Soni [email protected] has adjusted some coefficients to avoid over/under-flows in the decoder.

Phil Schatzmann [email protected] has added cmake-glue and Arduino support.

Librarized by Sippy Software, Inc.

Using libg722 as an Arduino Library

You can download the library as zip and call include Library -> zip library. Or you can git clone this project into the Arduino libraries folder e.g. with

cd  ~/Documents/Arduino/libraries
git clone https://github.com/sippy/libg722.git

The use of git is recommended because you can easily update to the latest version just by executing the git pull command in the project folder.

License

This code is mostly Public Domain. Library test code is under BSD 2-clause license.

See LICENSE for copyright details and each individual file for specifics.