1 /********************************************************************
3 * THIS FILE IS PART OF THE Ogg Vorbis SOFTWARE CODEC SOURCE CODE. *
4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS SOURCE IS GOVERNED BY *
5 * THE GNU PUBLIC LICENSE 2, WHICH IS INCLUDED WITH THIS SOURCE. *
6 * PLEASE READ THESE TERMS DISTRIBUTING. *
8 * THE OggSQUISH SOURCE CODE IS (C) COPYRIGHT 1994-2000 *
9 * by Monty <monty@xiph.org> and The XIPHOPHORUS Company *
10 * http://www.xiph.org/ *
12 ********************************************************************
14 function: LPC low level routines
15 last mod: $Id: lpc.h,v 1.9 2000/01/28 09:05:12 xiphmont Exp $
17 ********************************************************************/
22 #include "vorbis/codec.h"
25 typedef struct lpclook{
26 /* en/decode lookups */
37 extern void lpc_init(lpc_lookup *l,int n, long mapped, long rate, int m);
38 extern void lpc_clear(lpc_lookup *l);
40 /* simple linear scale LPC code */
41 extern double vorbis_lpc_from_data(double *data,double *lpc,int n,int m);
42 extern double vorbis_lpc_from_spectrum(double *curve,double *lpc,lpc_lookup *l);
45 extern double vorbis_curve_to_lpc(double *curve,double *lpc,lpc_lookup *l);
46 extern void vorbis_lpc_to_curve(double *curve,double *lpc, double amp,
49 /* standard lpc stuff */
50 extern void vorbis_lpc_residue(double *coeff,double *prime,int m,
52 extern void vorbis_lpc_predict(double *coeff,double *prime,int m,