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/* ITU-T G.729 Software Package Release 2 (November 2006) */ 
/* 
   ITU-T G.729 Annex C - Reference C code for floating point 
                         implementation of G.729 
                         Version 1.01 of 15.September.98 
*/ 
 
/* 
---------------------------------------------------------------------- 
                    COPYRIGHT NOTICE 
---------------------------------------------------------------------- 
   ITU-T G.729 Annex C ANSI C source code 
   Copyright (C) 1998, AT&T, France Telecom, NTT, University of 
   Sherbrooke.  All rights reserved. 
 
---------------------------------------------------------------------- 
*/ 
 
/* 
 File : LSPDEC.C 
 Used for the floating point version of both 
 G.729 main body and G.729A 
*/ 
#include  
#include "typedef.h" 
#include "version.h" 
#ifdef VER_G729A 
 #include "ld8a.h" 
 #include "tab_ld8a.h" 
#else 
 #include "ld8k.h" 
 #include "tab_ld8k.h" 
#endif 
 
/* Prototype definitions of static functions */ 
static void lsp_iqua_cs( int prm[], FLOAT lsp[], int erase); 
 
/* static memory */ 
static FLOAT freq_prev[MA_NP][M];    /* previous LSP vector       */ 
static FLOAT freq_prev_reset[M] = {  /* previous LSP vector(init) */ 
 (F)0.285599,  (F)0.571199,  (F)0.856798,  (F)1.142397,  (F)1.427997, 
 (F)1.713596,  (F)1.999195,  (F)2.284795,  (F)2.570394,  (F)2.855993 
};     /* PI*(float)(j+1)/(float)(M+1) */ 
 
/* static memory for frame erase operation */ 
static int prev_ma;                  /* previous MA prediction coef.*/ 
static FLOAT prev_lsp[M];            /* previous LSP vector         */ 
 
 
/*---------------------------------------------------------------------------- 
 * Lsp_decw_reset -   set the previous LSP vectors 
 *---------------------------------------------------------------------------- 
 */ 
void lsp_decw_reset(void) 
{ 
   int  i; 
 
   for(i=0; i> NC0_B) & 1; 
        code0 = prm[0] & (INT16)(NC0 - 1); 
        code1 = (prm[1] >> NC1_B) & (INT16)(NC1 - 1); 
        code2 = prm[1] & (INT16)(NC1 - 1); 
 
        lsp_get_quant(lspcb1, lspcb2, code0, code1, code2, fg[mode_index], 
              freq_prev, lsp_q, fg_sum[mode_index]); 
 
        copy(lsp_q, prev_lsp, M ); 
        prev_ma = mode_index; 
     } 
   else                         /* Frame erased */ 
     { 
       copy(prev_lsp, lsp_q, M ); 
 
        /* update freq_prev */ 
       lsp_prev_extract(prev_lsp, buf, 
          fg[prev_ma], freq_prev, fg_sum_inv[prev_ma]); 
       lsp_prev_update(buf, freq_prev); 
     } 
     return; 
} 
/*---------------------------------------------------------------------------- 
 * d_lsp - decode lsp parameters 
 *---------------------------------------------------------------------------- 
 */ 
void d_lsp( 
    int     index[],    /* input : indexes                 */ 
    FLOAT   lsp_q[],    /* output: decoded lsp             */ 
    int     bfi         /* input : frame erase information */ 
) 
{ 
   int i; 
 
   lsp_iqua_cs(index, lsp_q,bfi); /* decode quantized information */ 
 
   /* Convert LSFs to LSPs */ 
 
   for (i=0; i