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view libtwamr/int_lsf.h @ 602:72cdae602d6e

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libgsmhr1/dec_func.c: rm unused static functions In the original code, sp_dec.c held two kinds of functions: those needed only as part of the decoder, and those used by both decoder and encoder engines. In this library, we have moved the latter class of functions to dec_func.c module. Almost all static functions from the original sp_dec.c, with the exception of aToRc(), are needed only on sp_dec.c side of the new divide - remove them from dec_func.c, where they became dead code.
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 04 Dec 2025 18:58:22 +0000
parents 693ea1d5cf1e
children
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/*
********************************************************************************
*
*      GSM AMR-NB speech codec   R98   Version 7.6.0   December 12, 2001
*                                R99   Version 3.3.0                
*                                REL-4 Version 4.1.0                
*
********************************************************************************
*
*      File             : int_lsf.h
*      Purpose          : Interpolates the LSFs
*
********************************************************************************
*/
#ifndef int_lsf_h
#define int_lsf_h "$Id $"
 
/*
********************************************************************************
*                         INCLUDE FILES
********************************************************************************
*/
#include "typedef.h"
 
/*
********************************************************************************
*                         DEFINITION OF DATA TYPES
********************************************************************************
*/
 
/*
********************************************************************************
*                         DECLARATION OF PROTOTYPES
********************************************************************************
*/

/*
**************************************************************************
*
*  Function    : Int_lsf
*  Purpose     : Interpolates the LSFs for selected subframe
*  Description : The 20 ms speech frame is divided into 4 subframes.
*                The LSFs are interpolated at the 1st, 2nd and 3rd
*                subframe and only forwarded at the 4th subframe.
*
*                      |------|------|------|------|
*                         sf1    sf2    sf3    sf4
*                   F0                          F1
*      
*                 sf1:   3/4 F0 + 1/4 F1         sf3:   1/4 F0 + 3/4 F1
*                 sf2:   1/2 F0 + 1/2 F1         sf4:       F1
*  Returns     : void
*
**************************************************************************
*/
void Int_lsf (
    Word16 lsf_old[], /* i : LSF vector at the 4th SF of past frame          */
    Word16 lsf_new[], /* i : LSF vector at the 4th SF of present frame       */
    Word16 i_subfr,   /* i : Pointer to current sf (equal to 0,40,80 or 120) */
    Word16 lsf_out[]  /* o : interpolated LSF parameters for current sf      */
);
 
#endif