ref: e82315d28bb5b1e866dad32fadc801c14c5cb1b4
dir: /libfaad/filtbank.c/
/*
** FAAD - Freeware Advanced Audio Decoder
** Copyright (C) 2002 M. Bakker
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or
** (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
**
** $Id: filtbank.c,v 1.2 2002/02/18 10:01:05 menno Exp $
**/
#include "common.h"
#include <stdlib.h>
#ifdef USE_FMATH
#include <mathf.h>
#else
#include <math.h>
#endif
#include <assert.h>
#include "filtbank.h"
#include "syntax.h"
#include "kbd_win.h"
#include "mdct.h"
real_t *long_window[2];
real_t *short_window[2];
void filter_bank_init(fb_info *fb)
{
uint16_t i;
make_fft_order(fb->unscrambled64, fb->unscrambled512);
fb->sin_long = malloc(BLOCK_LEN_LONG*sizeof(real_t));
fb->sin_short = malloc(BLOCK_LEN_SHORT*sizeof(real_t));
long_window[0] = fb->sin_long;
long_window[1] = kbd_long;
short_window[0] = fb->sin_short;
short_window[1] = kbd_short;
/* calculate the sine windows */
for (i = 0; i < BLOCK_LEN_LONG; i++)
#ifdef USE_FMATH
fb->sin_long[i] = sinf(M_PI / (2.0f * BLOCK_LEN_LONG) * (i + 0.5));
#else
fb->sin_long[i] = (real_t)sin(M_PI / (2.0 * BLOCK_LEN_LONG) * (i + 0.5));
#endif
for (i = 0; i < BLOCK_LEN_SHORT; i++)
#ifdef USE_FMATH
fb->sin_short[i] = sinf(M_PI / (2.0f * BLOCK_LEN_SHORT) * (i + 0.5));
#else
fb->sin_short[i] = (real_t)sin(M_PI / (2.0 * BLOCK_LEN_SHORT) * (i + 0.5));
#endif
}
void filter_bank_end(fb_info *fb)
{
if (fb->sin_long) free(fb->sin_long);
if (fb->sin_short) free(fb->sin_short);
}
static INLINE void vcopy(real_t *src, real_t *dest, uint16_t vlen)
{
int16_t i;
assert(vlen % 16 == 0);
for (i = vlen/16-1; i >= 0; --i)
{
*dest++ = *src++; *dest++ = *src++; *dest++ = *src++; *dest++ = *src++;
*dest++ = *src++; *dest++ = *src++; *dest++ = *src++; *dest++ = *src++;
*dest++ = *src++; *dest++ = *src++; *dest++ = *src++; *dest++ = *src++;
*dest++ = *src++; *dest++ = *src++; *dest++ = *src++; *dest++ = *src++;
}
}
static INLINE void vzero(real_t *dest, uint16_t vlen)
{
int16_t i;
assert(vlen % 16 == 0);
for (i = vlen/16-1; i >= 0; --i)
{
*dest-- = 0; *dest-- = 0; *dest-- = 0; *dest-- = 0;
*dest-- = 0; *dest-- = 0; *dest-- = 0; *dest-- = 0;
*dest-- = 0; *dest-- = 0; *dest-- = 0; *dest-- = 0;
*dest-- = 0; *dest-- = 0; *dest-- = 0; *dest-- = 0;
}
}
static INLINE void vmult1(real_t *src1, real_t *src2, real_t *dest, uint16_t vlen)
{
int16_t i;
assert(vlen % 16 == 0);
for (i = vlen/16-1; i >= 0 ; --i)
{
*dest++ = *src1++ * *src2++; *dest++ = *src1++ * *src2++;
*dest++ = *src1++ * *src2++; *dest++ = *src1++ * *src2++;
*dest++ = *src1++ * *src2++; *dest++ = *src1++ * *src2++;
*dest++ = *src1++ * *src2++; *dest++ = *src1++ * *src2++;
*dest++ = *src1++ * *src2++; *dest++ = *src1++ * *src2++;
*dest++ = *src1++ * *src2++; *dest++ = *src1++ * *src2++;
*dest++ = *src1++ * *src2++; *dest++ = *src1++ * *src2++;
*dest++ = *src1++ * *src2++; *dest++ = *src1++ * *src2++;
}
}
static INLINE void vmult2(real_t *src1, real_t *src2, real_t *dest, uint16_t vlen)
{
int16_t i;
assert(vlen % 16 == 0);
for (i = vlen/16-1; i >= 0 ; --i)
{
*dest++ = *src1++ * *src2--; *dest++ = *src1++ * *src2--;
*dest++ = *src1++ * *src2--; *dest++ = *src1++ * *src2--;
*dest++ = *src1++ * *src2--; *dest++ = *src1++ * *src2--;
*dest++ = *src1++ * *src2--; *dest++ = *src1++ * *src2--;
*dest++ = *src1++ * *src2--; *dest++ = *src1++ * *src2--;
*dest++ = *src1++ * *src2--; *dest++ = *src1++ * *src2--;
*dest++ = *src1++ * *src2--; *dest++ = *src1++ * *src2--;
*dest++ = *src1++ * *src2--; *dest++ = *src1++ * *src2--;
}
}
static INLINE void vadd(real_t *src1, real_t *src2, real_t *dest, uint16_t vlen)
{
int16_t i;
assert(vlen % 16 == 0);
for (i = vlen/16-1; i >= 0; --i)
{
*dest++ = *src1++ + *src2++; *dest++ = *src1++ + *src2++;
*dest++ = *src1++ + *src2++; *dest++ = *src1++ + *src2++;
*dest++ = *src1++ + *src2++; *dest++ = *src1++ + *src2++;
*dest++ = *src1++ + *src2++; *dest++ = *src1++ + *src2++;
*dest++ = *src1++ + *src2++; *dest++ = *src1++ + *src2++;
*dest++ = *src1++ + *src2++; *dest++ = *src1++ + *src2++;
*dest++ = *src1++ + *src2++; *dest++ = *src1++ + *src2++;
*dest++ = *src1++ + *src2++; *dest++ = *src1++ + *src2++;
}
}
static INLINE void imdct(fb_info *fb, real_t *in_data, real_t *out_data, uint16_t len)
{
switch (len)
{
case 2048:
IMDCT_long(in_data, out_data, fb->unscrambled512);
return;
case 256:
IMDCT_short(in_data, out_data, fb->unscrambled64);
return;
}
}
static INLINE void mdct(fb_info *fb, real_t *in_data, real_t *out_data, uint16_t len)
{
switch (len)
{
case 2048:
MDCT_long(in_data, out_data, fb->unscrambled512);
return;
case 256:
MDCT_short(in_data, out_data, fb->unscrambled64);
return;
}
}
void ifilter_bank(fb_info *fb, uint8_t window_sequence, uint8_t window_shape,
uint8_t window_shape_prev, real_t *freq_in, real_t *time_buff,
real_t *time_out)
{
real_t *o_buf, transf_buf[2*BLOCK_LEN_LONG];
real_t *window_long;
real_t *window_long_prev;
real_t *window_short;
real_t *window_short_prev;
real_t *window_short_prev_ptr;
real_t *fp;
int8_t win;
uint16_t nlong = 1024;
uint16_t nshort = 128;
uint16_t nflat_ls = (nlong-nshort)/2;
window_long = long_window[window_shape];
window_long_prev = long_window[window_shape_prev];
window_short = short_window[window_shape];
window_short_prev = short_window[window_shape_prev];
/* pointer to previous window function */
window_short_prev_ptr = window_short_prev;
vcopy(time_buff, time_out, nlong);
o_buf = time_out;
switch (window_sequence)
{
case ONLY_LONG_SEQUENCE:
/* inverse transform */
imdct(fb, freq_in, transf_buf, 2*nlong);
/* window function (previous) on first half of the new data */
vmult1(transf_buf, window_long_prev, transf_buf, nlong);
/* overlap and add second half of the old data with first half
of the new data */
vadd(transf_buf, o_buf, o_buf, nlong);
/* reversed window function on second half of the new data */
vmult2(transf_buf+nlong, window_long+nlong-1, o_buf+nlong, nlong);
break;
case LONG_START_SEQUENCE:
/* inverse transform */
imdct(fb, freq_in, transf_buf, 2*nlong);
/* window function (previous) on first half of the new data */
vmult1(transf_buf, window_long_prev, transf_buf, nlong);
/* overlap and add second half of the old data with first half
of the new data */
vadd(transf_buf, o_buf, o_buf, nlong);
/* copy data from nlong upto (3*nlong-nshort)/4; (window function = 1.0) */
vcopy(transf_buf+nlong, o_buf+nlong, nflat_ls);
/* reversed window function on part of second half of the new data */
vmult2(transf_buf+nlong+nflat_ls, window_short+nshort-1,
o_buf+nlong+nflat_ls, nshort);
/* zero rest of the data; (window function = 0.0) */
vzero(o_buf+2*nlong-1, nflat_ls);
break;
case EIGHT_SHORT_SEQUENCE:
fp = o_buf + nflat_ls;
for (win = 8-1; win >= 0; --win)
{
/* inverse transform */
imdct(fb, freq_in, transf_buf, 2*nshort);
/* window function (previous) on first half of the new data */
vmult1(transf_buf, window_short_prev_ptr, transf_buf, nshort);
/* overlap and add second half of the old data with first half
of the new data */
vadd(transf_buf, fp, fp, nshort);
/* reversed window function on second half of the new data */
vmult2(transf_buf+nshort, window_short+nshort-1, fp+nshort, nshort);
/* shift to next short block */
freq_in += nshort;
fp += nshort;
window_short_prev_ptr = window_short;
}
vzero(o_buf+2*nlong-1, nflat_ls);
break;
case LONG_STOP_SEQUENCE:
/* inverse transform */
imdct(fb, freq_in, transf_buf, 2*nlong);
/* zero first part of first half of the data (window function = 0.0) */
vzero(transf_buf+nflat_ls-1, nflat_ls);
/* window function (previous) on part of the first half of
the new data */
vmult1(transf_buf+nflat_ls, window_short_prev_ptr,
transf_buf+nflat_ls, nshort);
/* third part of the stop sequence window is window function = 1,
so no need to actually apply that */
/* overlap and add second half of the old data with first half
of the new data */
vadd(transf_buf+nflat_ls, o_buf+nflat_ls, o_buf+nflat_ls, nshort);
/* copy last part of first half of the data (window function = 1.0) */
vcopy(transf_buf+nflat_ls+nshort, o_buf+nflat_ls+nshort, nflat_ls);
/* reversed window function on second half of the new data */
vmult2(transf_buf+nlong, window_long+nlong-1, o_buf+nlong, nlong);
break;
}
/* save second half of data */
vcopy(o_buf+nlong, time_buff, nlong);
}
/* only works for LTP -> no overlapping */
void filter_bank_ltp(fb_info *fb, uint8_t window_sequence, uint8_t window_shape,
uint8_t window_shape_prev, real_t *in_data, real_t *out_mdct)
{
int8_t win;
real_t windowed_buf[2*1024];
real_t *p_o_buf;
real_t *window_long;
real_t *window_long_prev;
real_t *window_short;
real_t *window_short_prev;
real_t *window_short_prev_ptr;
uint16_t nlong = 1024;
uint16_t nshort = 128;
uint16_t nflat_ls = (nlong-nshort)/2;
window_long = long_window[window_shape];
window_long_prev = long_window[window_shape_prev];
window_short = short_window[window_shape];
window_short_prev = short_window[window_shape_prev];
window_short_prev_ptr = window_short_prev;
p_o_buf = in_data;
switch(window_sequence)
{
case ONLY_LONG_SEQUENCE:
vmult1(p_o_buf, window_long_prev, windowed_buf, nlong);
vmult2(p_o_buf+nlong, window_long+nlong-1, windowed_buf+nlong, nlong);
mdct(fb, windowed_buf, out_mdct, 2*nlong);
break;
case LONG_START_SEQUENCE:
vmult1(p_o_buf, window_long_prev, windowed_buf, nlong);
vcopy(p_o_buf+nlong, windowed_buf+nlong, nflat_ls);
vmult2(p_o_buf+nlong+nflat_ls, window_short+nshort-1, windowed_buf+nlong+nflat_ls, nshort);
vzero(windowed_buf+2*nlong-1, nflat_ls);
mdct(fb, windowed_buf, out_mdct, 2*nlong);
break;
case EIGHT_SHORT_SEQUENCE:
for (win = 8-1; win >= 0; --win)
{
vmult1(p_o_buf, window_short_prev_ptr, windowed_buf, nshort);
vmult2(p_o_buf+nshort, window_short+nshort-1, windowed_buf+nshort, nshort);
mdct(fb, windowed_buf, out_mdct, 2*nshort);
out_mdct += nshort;
p_o_buf += 2*nshort;
window_short_prev_ptr = window_short;
}
break;
case LONG_STOP_SEQUENCE:
vzero(windowed_buf+nflat_ls-1, nflat_ls);
vmult1(p_o_buf+nflat_ls, window_short_prev_ptr, windowed_buf+nflat_ls, nshort);
vcopy(p_o_buf+nflat_ls+nshort, windowed_buf+nflat_ls+nshort, nflat_ls);
vmult2(p_o_buf+nlong, window_long+nlong-1, windowed_buf+nlong, nlong);
mdct(fb, windowed_buf, out_mdct, 2*nlong);
break;
}
}