xref: /external/speex/libspeex/lsp.h

/*---------------------------------------------------------------------------*\
Original Copyright
	FILE........: AK2LSPD.H
	TYPE........: Turbo C header file
	COMPANY.....: Voicetronix
	AUTHOR......: James Whitehall
	DATE CREATED: 21/11/95

Modified by Jean-Marc Valin

    This file contains functions for converting Linear Prediction
    Coefficients (LPC) to Line Spectral Pair (LSP) and back. Note that the
    LSP coefficients are not in radians format but in the x domain of the
    unit circle.

\*---------------------------------------------------------------------------*/
/**
   @file lsp.h
   @brief Line Spectral Pair (LSP) functions.
*/
/* Speex License:

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   modification, are permitted provided that the following conditions
   are met:

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   notice, this list of conditions and the following disclaimer.

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   - 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
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*/

#ifndef __AK2LSPD__
#define __AK2LSPD__

#include "arch.h"

int lpc_to_lsp (spx_coef_t *a, int lpcrdr, spx_lsp_t *freq, int nb, spx_word16_t delta, char *stack);
void lsp_to_lpc(spx_lsp_t *freq, spx_coef_t *ak, int lpcrdr, char *stack);

/*Added by JMV*/
void lsp_enforce_margin(spx_lsp_t *lsp, int len, spx_word16_t margin);

void lsp_interpolate(spx_lsp_t *old_lsp, spx_lsp_t *new_lsp, spx_lsp_t *interp_lsp, int len, int subframe, int nb_subframes);

#endif	/* __AK2LSPD__ */