ref: c9715c6aea0091de8b86602f7db0f315b370f4b2
dir: /libfaac/aacquant.c/
/*
* FAAC - Freeware Advanced Audio Coder
* Copyright (C) 2001 Menno Bakker
* Copyright (C) 2002, 2003 Krzysztof Nikiel
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id: aacquant.c,v 1.20 2003/06/26 19:19:21 knik Exp $
*/
#include <math.h>
#include <stdlib.h>
#include "aacquant.h"
#include "coder.h"
#include "huffman.h"
#include "psych.h"
#include "util.h"
#define XRPOW_FTOI(src,dest) ((dest) = (int)(src))
#define QUANTFAC(rx) adj43[rx]
#define ROUNDFAC 0.4054
static int FixNoise(CoderInfo *coderInfo,
const double *xr,
double *xr_pow,
int *xi,
double *xmin);
static void CalcAllowedDist(CoderInfo *coderInfo, PsyInfo *psyInfo,
double *xr, double *xmin, int quality);
double *pow43;
double *adj43;
double *adj43asm;
void AACQuantizeInit(CoderInfo *coderInfo, unsigned int numChannels)
{
unsigned int channel, i;
pow43 = (double*)AllocMemory(PRECALC_SIZE*sizeof(double));
adj43 = (double*)AllocMemory(PRECALC_SIZE*sizeof(double));
adj43asm = (double*)AllocMemory(PRECALC_SIZE*sizeof(double));
pow43[0] = 0.0;
for(i=1;i<PRECALC_SIZE;i++)
pow43[i] = pow((double)i, 4.0/3.0);
adj43asm[0] = 0.0;
for (i = 1; i < PRECALC_SIZE; i++)
adj43asm[i] = i - 0.5 - pow(0.5 * (pow43[i - 1] + pow43[i]),0.75);
for (i = 0; i < PRECALC_SIZE-1; i++)
adj43[i] = (i + 1) - pow(0.5 * (pow43[i] + pow43[i + 1]), 0.75);
adj43[i] = 0.5;
for (channel = 0; channel < numChannels; channel++) {
coderInfo[channel].requantFreq = (double*)AllocMemory(BLOCK_LEN_LONG*sizeof(double));
}
}
void AACQuantizeEnd(CoderInfo *coderInfo, unsigned int numChannels)
{
unsigned int channel;
if (pow43) FreeMemory(pow43);
if (adj43) FreeMemory(adj43);
if (adj43asm) FreeMemory(adj43asm);
for (channel = 0; channel < numChannels; channel++) {
if (coderInfo[channel].requantFreq) FreeMemory(coderInfo[channel].requantFreq);
}
}
static void BalanceEnergy(CoderInfo *coderInfo,
const double *xr, const int *xi)
{
const double ifqstep = pow(2.0, 0.25);
const double logstep_1 = 1.0 / log(ifqstep);
int sb;
int nsfb = coderInfo->nr_of_sfb;
int start, end;
int l;
double en0, enq;
int shift;
for (sb = 0; sb < nsfb; sb++)
{
double qfac_1;
start = coderInfo->sfb_offset[sb];
end = coderInfo->sfb_offset[sb+1];
qfac_1 = pow(2.0, -0.25*(coderInfo->scale_factor[sb] - coderInfo->global_gain));
en0 = 0.0;
enq = 0.0;
for (l = start; l < end; l++)
{
double xq;
if (!sb && !xi[l])
continue;
xq = pow43[xi[l]];
en0 += xr[l] * xr[l];
enq += xq * xq;
}
if (enq == 0.0)
continue;
enq *= qfac_1 * qfac_1;
shift = log(sqrt(enq / en0)) * logstep_1 + 1000.5;
shift -= 1000;
shift += coderInfo->scale_factor[sb];
coderInfo->scale_factor[sb] = shift;
}
}
static void UpdateRequant(CoderInfo *coderInfo, int *xi)
{
double *requant_xr = coderInfo->requantFreq;
int sb;
int i;
for (sb = 0; sb < coderInfo->nr_of_sfb; sb++)
{
double invQuantFac =
pow(2.0, -0.25*(coderInfo->scale_factor[sb] - coderInfo->global_gain));
int start = coderInfo->sfb_offset[sb];
int end = coderInfo->sfb_offset[sb + 1];
for (i = start; i < end; i++)
requant_xr[i] = pow43[xi[i]] * invQuantFac;
}
}
int AACQuantize(CoderInfo *coderInfo,
PsyInfo *psyInfo,
ChannelInfo *channelInfo,
int *cb_width,
int num_cb,
double *xr,
int quality)
{
int sb, i, do_q = 0;
int bits = 0, sign;
double xr_pow[FRAME_LEN];
double xmin[MAX_SCFAC_BANDS];
int xi[FRAME_LEN];
/* Use local copy's */
int *scale_factor = coderInfo->scale_factor;
/* Set all scalefactors to 0 */
coderInfo->global_gain = 0;
for (sb = 0; sb < coderInfo->nr_of_sfb; sb++)
scale_factor[sb] = 0;
/* Compute xr_pow */
for (i = 0; i < FRAME_LEN; i++) {
double temp = fabs(xr[i]);
xr_pow[i] = sqrt(temp * sqrt(temp));
do_q += (temp > 1E-20);
}
if (do_q) {
CalcAllowedDist(coderInfo, psyInfo, xr, xmin, quality);
coderInfo->global_gain = 0;
FixNoise(coderInfo, xr, xr_pow, xi, xmin);
BalanceEnergy(coderInfo, xr, xi);
UpdateRequant(coderInfo, xi);
for ( i = 0; i < FRAME_LEN; i++ ) {
sign = (xr[i] < 0) ? -1 : 1;
xi[i] *= sign;
coderInfo->requantFreq[i] *= sign;
}
} else {
coderInfo->global_gain = 0;
SetMemory(xi, 0, FRAME_LEN*sizeof(int));
}
BitSearch(coderInfo, xi);
/* offset the difference of common_scalefac and scalefactors by SF_OFFSET */
for (i = 0; i < coderInfo->nr_of_sfb; i++) {
if ((coderInfo->book_vector[i]!=INTENSITY_HCB)&&(coderInfo->book_vector[i]!=INTENSITY_HCB2)) {
scale_factor[i] = coderInfo->global_gain - scale_factor[i] + SF_OFFSET;
}
}
coderInfo->global_gain = scale_factor[0];
#if 0
printf("global gain: %d\n", coderInfo->global_gain);
for (i = 0; i < coderInfo->nr_of_sfb; i++)
printf("sf %d: %d\n", i, coderInfo->scale_factor[i]);
#endif
/* place the codewords and their respective lengths in arrays data[] and len[] respectively */
/* there are 'counter' elements in each array, and these are variable length arrays depending on the input */
coderInfo->spectral_count = 0;
sb = 0;
for(i = 0; i < coderInfo->nr_of_sfb; i++) {
OutputBits(
coderInfo,
coderInfo->book_vector[i],
xi,
coderInfo->sfb_offset[i],
coderInfo->sfb_offset[i+1]-coderInfo->sfb_offset[i]);
if (coderInfo->book_vector[i])
sb = i;
}
// FIXME: Check those max_sfb/nr_of_sfb. Isn't it the same?
coderInfo->max_sfb = coderInfo->nr_of_sfb = sb + 1;
return bits;
}
#if 1 /* TAKEHIRO_IEEE754_HACK */
typedef union {
float f;
int i;
} fi_union;
#define MAGIC_FLOAT (65536*(128))
#define MAGIC_INT 0x4b000000
#if 0
static void Quantize(const double *xp, int *pi, double istep)
{
int j;
fi_union *fi;
fi = (fi_union *)pi;
for (j = FRAME_LEN/4 - 1; j >= 0; --j) {
double x0 = istep * xp[0];
double x1 = istep * xp[1];
double x2 = istep * xp[2];
double x3 = istep * xp[3];
x0 += MAGIC_FLOAT; fi[0].f = x0;
x1 += MAGIC_FLOAT; fi[1].f = x1;
x2 += MAGIC_FLOAT; fi[2].f = x2;
x3 += MAGIC_FLOAT; fi[3].f = x3;
fi[0].f = x0 + (adj43asm - MAGIC_INT)[fi[0].i];
fi[1].f = x1 + (adj43asm - MAGIC_INT)[fi[1].i];
fi[2].f = x2 + (adj43asm - MAGIC_INT)[fi[2].i];
fi[3].f = x3 + (adj43asm - MAGIC_INT)[fi[3].i];
fi[0].i -= MAGIC_INT;
fi[1].i -= MAGIC_INT;
fi[2].i -= MAGIC_INT;
fi[3].i -= MAGIC_INT;
fi += 4;
xp += 4;
}
}
#endif
static void QuantizeBand(const double *xp, int *pi, double istep,
int offset, int end)
{
int j;
fi_union *fi;
fi = (fi_union *)pi;
for (j = offset; j < end; j++)
{
double x0 = istep * xp[j];
x0 += MAGIC_FLOAT; fi[j].f = x0;
fi[j].f = x0 + (adj43asm - MAGIC_INT)[fi[j].i];
fi[j].i -= MAGIC_INT;
}
}
#else
static void Quantize(const double *xr, int *ix, double istep)
{
int j;
for (j = FRAME_LEN/8; j > 0; --j) {
double x1, x2, x3, x4, x5, x6, x7, x8;
int rx1, rx2, rx3, rx4, rx5, rx6, rx7, rx8;
x1 = *xr++ * istep;
x2 = *xr++ * istep;
XRPOW_FTOI(x1, rx1);
x3 = *xr++ * istep;
XRPOW_FTOI(x2, rx2);
x4 = *xr++ * istep;
XRPOW_FTOI(x3, rx3);
x5 = *xr++ * istep;
XRPOW_FTOI(x4, rx4);
x6 = *xr++ * istep;
XRPOW_FTOI(x5, rx5);
x7 = *xr++ * istep;
XRPOW_FTOI(x6, rx6);
x8 = *xr++ * istep;
XRPOW_FTOI(x7, rx7);
x1 += QUANTFAC(rx1);
XRPOW_FTOI(x8, rx8);
x2 += QUANTFAC(rx2);
XRPOW_FTOI(x1,*ix++);
x3 += QUANTFAC(rx3);
XRPOW_FTOI(x2,*ix++);
x4 += QUANTFAC(rx4);
XRPOW_FTOI(x3,*ix++);
x5 += QUANTFAC(rx5);
XRPOW_FTOI(x4,*ix++);
x6 += QUANTFAC(rx6);
XRPOW_FTOI(x5,*ix++);
x7 += QUANTFAC(rx7);
XRPOW_FTOI(x6,*ix++);
x8 += QUANTFAC(rx8);
XRPOW_FTOI(x7,*ix++);
XRPOW_FTOI(x8,*ix++);
}
}
#endif
static void CalcAllowedDist(CoderInfo *coderInfo, PsyInfo *psyInfo,
double *xr, double *xmin, int quality)
{
int sfb, start, end, l;
const double globalthr = 29.7 / (double)quality;
int last = coderInfo->lastx;
int lastsb = 0;
static const double minfix = 1.5;
int *cb_offset = coderInfo->sfb_offset;
int num_cb = coderInfo->nr_of_sfb;
double avgenrg = coderInfo->avgenrg;
for (sfb = 0; sfb < num_cb; sfb++)
{
if (last > cb_offset[sfb])
lastsb = sfb;
}
for (sfb = 0; sfb < num_cb; sfb++)
{
double thr, tmp;
double enrg = 0.0;
start = cb_offset[sfb];
end = cb_offset[sfb + 1];
if (sfb > lastsb)
{
xmin[sfb] = 0;
continue;
}
for (l = start; l < end; l++)
enrg += xr[l]*xr[l];
thr = pow((double)(end-start)*avgenrg/enrg, 0.425*(lastsb-sfb)/lastsb + 0.075);
tmp = minfix * (double)(start + 400) / (double)last;
if (tmp < thr)
thr = tmp;
xmin[sfb] = ((coderInfo->block_type == ONLY_SHORT_WINDOW) ? 0.7 : 1.0)
* globalthr * thr;
}
}
static int FixNoise(CoderInfo *coderInfo,
const double *xr,
double *xr_pow,
int *xi,
double *xmin)
{
int i, sb;
int start, end;
double quantvol, diffvol;
double quantfac;
double tmp;
const double ifqstep = pow(2.0, 0.1875);
const double log_ifqstep = 1.0 / log(ifqstep);
const double maxstep = 0.05;
for (sb = 0; sb < coderInfo->nr_of_sfb; sb++)
{
double sfacfix;
double fixstep = 0.25;
int sfac;
double fac;
int dist;
double sfacfix0 = 1.0, dist0 = 1e50;
double maxx;
start = coderInfo->sfb_offset[sb];
end = coderInfo->sfb_offset[sb+1];
if (!xmin[sb])
goto nullsfb;
maxx = 0.0;
for (i = start; i < end; i++)
{
if (xr_pow[i] > maxx)
maxx = xr_pow[i];
}
//printf("band %d: maxx: %f\n", sb, maxx);
if (maxx < 10.0)
{
nullsfb:
for (i = start; i < end; i++)
xi[i] = 0;
coderInfo->scale_factor[sb] = 10;
continue;
}
sfacfix = 1.0 / maxx;
sfac = log(sfacfix) * log_ifqstep - 0.5;
for (i = start; i < end; i++)
xr_pow[i] *= sfacfix;
maxx *= sfacfix;
coderInfo->scale_factor[sb] = sfac;
QuantizeBand(xr_pow, xi, IPOW20(coderInfo->global_gain), start, end);
//printf("\tsfac: %d\n", sfac);
calcdist:
quantfac = pow(2.0, 0.25*(coderInfo->scale_factor[sb] - coderInfo->global_gain));
quantvol = 0.0;
diffvol = 0.0;
for (i = start; i < end; i++)
{
tmp = pow43[xi[i]];
quantvol += tmp * tmp;
diffvol += fabs(fabs(xr[i]) * quantfac - tmp);
}
quantvol = sqrt(quantvol/(double)(end-start)) * (double)(end-start);
//printf("\tdiffvol: %f, qvol: %f\n", diffvol, quantvol);
tmp = diffvol / quantvol;
if (fabs(fixstep) > maxstep)
{
double dd = 0.5*(tmp / xmin[sb] - 1.0);
if (fabs(dd) < fabs(fixstep))
{
fixstep = dd;
if (fabs(fixstep) < maxstep)
fixstep = maxstep * ((fixstep > 0) ? 1 : -1);
}
}
if (fixstep > 0)
{
if (tmp < dist0)
{
dist0 = tmp;
sfacfix0 = sfacfix;
}
else
{
if (fixstep > .1)
fixstep = .1;
}
}
else
{
dist0 = tmp;
sfacfix0 = sfacfix;
}
dist = (tmp > xmin[sb]);
fac = 0.0;
if (fabs(fixstep) >= maxstep)
{
if ((dist && (fixstep < 0))
|| (!dist && (fixstep > 0)))
{
fixstep = -0.5 * fixstep;
}
fac = 1.0 + fixstep;
}
else if (dist)
{
fac = 1.0 + fabs(fixstep);
}
if (fac != 0.0)
{
if (maxx * fac >= IXMAX_VAL)
{
// restore best noise
fac = sfacfix0 / sfacfix;
for (i = start; i < end; i++)
xr_pow[i] *= fac;
maxx *= fac;
sfacfix *= fac;
coderInfo->scale_factor[sb] = log(sfacfix) * log_ifqstep - 0.5;
QuantizeBand(xr_pow, xi, IPOW20(coderInfo->global_gain), start, end);
continue;
}
if (coderInfo->scale_factor[sb] < -10)
{
for (i = start; i < end; i++)
xr_pow[i] *= fac;
maxx *= fac;
sfacfix *= fac;
coderInfo->scale_factor[sb] = log(sfacfix) * log_ifqstep - 0.5;
QuantizeBand(xr_pow, xi, IPOW20(coderInfo->global_gain), start, end);
goto calcdist;
}
}
//printf("%d: %g\t%g - %g(%d)\n", sb, quantvol, diffvol/quantvol, xmin[sb], coderInfo->scale_factor[sb]);
}
return 0;
}
int SortForGrouping(CoderInfo* coderInfo,
PsyInfo *psyInfo,
ChannelInfo *channelInfo,
int *sfb_width_table,
double *xr)
{
int i,j,ii;
int index = 0;
double xr_tmp[1024];
int group_offset=0;
int k=0;
int windowOffset = 0;
/* set up local variables for used quantInfo elements */
int* sfb_offset = coderInfo->sfb_offset;
int* nr_of_sfb = &(coderInfo->nr_of_sfb);
int* window_group_length;
int num_window_groups;
*nr_of_sfb = coderInfo->max_sfb; /* Init to max_sfb */
window_group_length = coderInfo->window_group_length;
num_window_groups = coderInfo->num_window_groups;
/* calc org sfb_offset just for shortblock */
sfb_offset[k]=0;
for (k=1 ; k <*nr_of_sfb+1; k++) {
sfb_offset[k] = sfb_offset[k-1] + sfb_width_table[k-1];
}
/* sort the input spectral coefficients */
index = 0;
group_offset=0;
for (i=0; i< num_window_groups; i++) {
for (k=0; k<*nr_of_sfb; k++) {
for (j=0; j < window_group_length[i]; j++) {
for (ii=0;ii< sfb_width_table[k];ii++)
xr_tmp[index++] = xr[ii+ sfb_offset[k] + 128*j +group_offset];
}
}
group_offset += 128*window_group_length[i];
}
for (k=0; k<1024; k++){
xr[k] = xr_tmp[k];
}
/* now calc the new sfb_offset table for the whole p_spectrum vector*/
index = 0;
sfb_offset[index++] = 0;
windowOffset = 0;
for (i=0; i < num_window_groups; i++) {
for (k=0 ; k <*nr_of_sfb; k++) {
sfb_offset[index] = sfb_offset[index-1] + sfb_width_table[k]*window_group_length[i] ;
index++;
}
windowOffset += window_group_length[i];
}
*nr_of_sfb = *nr_of_sfb * num_window_groups; /* Number interleaved bands. */
return 0;
}
void CalcAvgEnrg(CoderInfo *coderInfo,
const double *xr)
{
int end, l;
int last = 0;
double totenrg = 0.0;
end = coderInfo->sfb_offset[coderInfo->nr_of_sfb];
for (l = 0; l < end; l++)
{
if (xr[l])
{
last = l;
totenrg += xr[l] * xr[l];
}
}
last++;
coderInfo->lastx = last;
coderInfo->avgenrg = totenrg / last;
}