ref: c4109ff50138fc5660db39fd2bd455ca5c58c065
dir: /imdct.c/
#include <math.h>
#include <stdlib.h>
#include "tf_main.h"
#include "transfo.h"
#include "block.h"
#include "dolby_win.h"
#define DPI 3.14159265358979323846264338327950288
static double zero = 0;
static void vcopy( double src[], double dest[], int inc_src, int inc_dest, int vlen )
{
int i;
for( i=0; i<vlen; i++ ) {
*dest = *src;
dest += inc_dest;
src += inc_src;
}
}
static void vmult( double src1[], double src2[], double dest[],
int inc_src1, int inc_src2, int inc_dest, int vlen )
{
int i;
for( i=0; i<vlen; i++ ) {
*dest = *src1 * *src2;
dest += inc_dest;
src1 += inc_src1;
src2 += inc_src2;
}
}
static void vadd( double src1[], double src2[], double dest[],
int inc_src1, int inc_src2, int inc_dest, int vlen )
{
int i;
for( i=0; i<vlen; i++ ) {
*dest = *src1 + *src2;
dest += inc_dest;
src1 += inc_src1;
src2 += inc_src2;
}
}
/* Calculate window */
void calc_window( double window[], int len, Window_shape wfun_select )
{
int i;
extern double dolby_win_1024[];
extern double dolby_win_128[];
switch(wfun_select)
{
case WS_FHG:
for( i=0; i<len; i++ )
window[i] = sin((DPI/(2*len)) * (i + 0.5));
break;
case WS_DOLBY:
switch(len)
{
case BLOCK_LEN_SHORT:
for( i=0; i<len; i++ )
window[i] = dolby_win_128[i];
break;
case BLOCK_LEN_LONG:
for( i=0; i<len; i++ )
window[i] = dolby_win_1024[i];
break;
}
break;
}
}
#define MAX_SHIFT_LEN_LONG 4096
/* %%%%%%%%%%%%%%%%% MDCT - STUFF %%%%%%%%%%%%%%%% */
void mdct( double in_data[], double out_data[], int len )
{
vcopy(in_data, out_data, 1, 1, len);
MDCT(out_data, len);
}
void buffer2freq(
double p_in_data[],
double p_out_mdct[],
double p_overlap[],
enum WINDOW_TYPE block_type,
Window_shape wfun_select, /* offers the possibility to select different window functions */
int nlong, /* shift length for long windows */
int nmed, /* shift length for medium windows */
int nshort, /* shift length for short windows */
Mdct_in overlap_select /* YT 970615 for son_PP */
)
{
double transf_buf[ 2*MAX_SHIFT_LEN_LONG ];
double windowed_buf[ 2*MAX_SHIFT_LEN_LONG ];
double *p_o_buf;
int k;
double window_long[MAX_SHIFT_LEN_LONG];
double window_long_prev[MAX_SHIFT_LEN_LONG];
double window_short[MAX_SHIFT_LEN_LONG];
double window_short_prev[MAX_SHIFT_LEN_LONG];
double *window_short_prev_ptr;
int nflat_ls = (nlong-nshort)/ 2;
int transfak_ls = nlong/nshort;
static Window_shape wfun_select_prev=WS_FHG;
static int firstTime=1;
window_short_prev_ptr = window_short_prev ;
calc_window( window_long, nlong, wfun_select );
calc_window( window_long_prev, nlong, wfun_select_prev );
calc_window( window_short, nshort, wfun_select );
calc_window( window_short_prev, nshort, wfun_select_prev );
/* create / shift old values */
/* We use p_overlap here as buffer holding the last frame time signal*/
/* YT 970615 for son_pp */
if (firstTime){
firstTime=0;
vcopy( &zero, transf_buf, 0, 1, nlong );
} else
vcopy( p_overlap, transf_buf, 1, 1, nlong );
/* Append new data */
vcopy( p_in_data, transf_buf+nlong, 1, 1, nlong );
vcopy( p_in_data, p_overlap, 1, 1, nlong );
/* Set ptr to transf-Buffer */
p_o_buf = transf_buf;
/* Separate action for each Block Type */
switch( block_type ) {
case ONLY_LONG_WINDOW :
vmult( p_o_buf, window_long_prev, windowed_buf, 1, 1, 1, nlong );
vmult( p_o_buf+nlong, window_long+nlong-1, windowed_buf+nlong, 1, -1, 1, nlong );
mdct( windowed_buf, p_out_mdct, 2*nlong );
break;
case LONG_SHORT_WINDOW :
vmult( p_o_buf, window_long_prev, windowed_buf, 1, 1, 1, nlong );
vcopy( p_o_buf+nlong, windowed_buf+nlong, 1, 1, nflat_ls );
vmult( p_o_buf+nlong+nflat_ls, window_short+nshort-1, windowed_buf+nlong+nflat_ls, 1, -1, 1, nshort );
vcopy( &zero, windowed_buf+2*nlong-1, 0, -1, nflat_ls );
mdct( windowed_buf, p_out_mdct, 2*nlong );
break;
case SHORT_LONG_WINDOW :
vcopy( &zero, windowed_buf, 0, 1, nflat_ls );
vmult( p_o_buf+nflat_ls, window_short_prev_ptr, windowed_buf+nflat_ls, 1, 1, 1, nshort );
vcopy( p_o_buf+nflat_ls+nshort, windowed_buf+nflat_ls+nshort, 1, 1, nflat_ls );
vmult( p_o_buf+nlong, window_long+nlong-1, windowed_buf+nlong, 1, -1, 1, nlong );
mdct( windowed_buf, p_out_mdct, 2*nlong );
break;
case ONLY_SHORT_WINDOW :
p_o_buf += nflat_ls;
for (k=transfak_ls-1; k-->=0; ) {
vmult( p_o_buf, window_short_prev_ptr, windowed_buf, 1, 1, 1, nshort );
vmult( p_o_buf+nshort, window_short+nshort-1, windowed_buf+nshort, 1, -1, 1, nshort );
mdct( windowed_buf, p_out_mdct, 2*nshort );
p_out_mdct += nshort;
/* YT 970615 for sonPP*/
p_o_buf += nshort;
window_short_prev_ptr = window_short;
}
break;
}
/* Set output data
vcopy(transf_buf, p_out_mdct,1, 1, nlong); */
/* --- Save old window shape --- */
wfun_select_prev = wfun_select;
}
/***********************************************************************************************/