The ITU G.722 codec, encode and decode part.

/*
 * SpanDSP - a series of DSP components for telephony
 *
 * g722_decode.c - The ITU G.722 codec, decode part.
 *
 * Written by Steve Underwood <steveu@coppice.org>
 *
 * Copyright (C) 2005 Steve Underwood
 *
 *  Despite my general liking of the GPL, I place my own contributions
 *  to this code in the public domain for the benefit of all mankind -
 *  even the slimy ones who might try to proprietize my work and use it
 *  to my detriment.
 *
 * Based in part on a single channel G.722 codec which is:
 *
 * Copyright (c) CMU 1993
 * Computer Science, Speech Group
 * Chengxiang Lu and Alex Hauptmann
 * /