Added libspeex to revision control, and updated Makefile to use it.

code/libspeex/lpc.h

@@ -0,0 +1,53 @@
+/* Copyright (C) 2002 Jean-Marc Valin */
+/**
+   @file lpc.h
+   @brief Functions for LPC (Linear Prediction Coefficients) analysis
+*/
+/*
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+   
+   - Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+   
+   - Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+   
+   - Neither the name of the Xiph.org Foundation nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+   
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
+   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifndef LPC_H
+#define LPC_H
+
+#include "arch.h"
+
+void _spx_autocorr(
+              const spx_word16_t * x,   /*  in: [0...n-1] samples x   */
+              spx_word16_t *ac,   /* out: [0...lag-1] ac values */
+              int lag, int   n);
+
+spx_word32_t                      /* returns minimum mean square error    */
+_spx_lpc(
+    spx_coef_t       * lpc, /*      [0...p-1] LPC coefficients      */
+    const spx_word16_t * ac,  /*  in: [0...p] autocorrelation values  */
+    int p
+    );
+
+
+#endif