/* Copyright (C) 2002 Jean-Marc Valin 
   File: lpc.h
   Functions for LPC (Linear Prediction Coefficients) analysis

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   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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*/

#ifndef LPC_H
#define LPC_H

void _spx_autocorr(
              const float * x,   /*  in: [0...n-1] samples x   */
              float *ac,   /* out: [0...lag-1] ac values */
              int lag, int   n);

float                      /* returns minimum mean square error    */
wld(
    float       * lpc, /*      [0...p-1] LPC coefficients      */
    const float * ac,  /*  in: [0...p] autocorrelation values  */
    float       * ref, /* out: [0...p-1] reflection coef's     */
    int p
    );


#endif