/*
* Parameter:
* coderInfo(IO)(O:coderInfo->scale_factor)
* xr(unused)
* xr_pow(IO)
* xi(O)
* xmin(I)
*/
static int32_t FixNoise(CoderInfo *coderInfo,
coef_t *xr_pow,
int32_t *xi,
real_32_t *xmin)
{
register int32_t i, sb;
int32_t start, end;
static real_32_t log_ifqstep = REAL_CONST(7.6943735514); // 1.0 / log(ifqstep)
static real_32_t realconst1 = REAL_CONST(0.6931471806); //log2
static real_32_t realconst2 = REAL_CONST(0.5);
for (sb = 0; sb < coderInfo->nr_of_sfb; sb++) {
eng_t eng = 0;
frac_t maxfixstep;
start = coderInfo->sfb_offset[sb];
end = coderInfo->sfb_offset[sb+1];
for ( i=start; i< end; i++)
eng += (int64_t)(COEF2INT(xr_pow[i]))*COEF2INT(xr_pow[i]);
if ( (eng == 0) || (xmin[sb]==0) )
maxfixstep = FRAC_ICONST(1);
else {
maxfixstep = faac_sqrt(eng/(end-start)*
MUL_R(xmin[sb],faac_sqrt(xmin[sb]))
);
if ( maxfixstep == 0 )
maxfixstep = FRAC_ICONST(1);
else
maxfixstep = ((real_t)1<<(FRAC_BITS+REAL_BITS))/maxfixstep;
}
#ifdef DUMP_MAXFIXSTEP
printf("sb = %d, maxfixstep = %.8f\n",sb, FRAC2FLOAT(maxfixstep));
#endif
for (i = start; i < end; i++) {
#ifdef DUMP_MAXFIXSTEP
printf("xr_pow[%d] = %.8f\t",i,COEF2FLOAT(xr_pow[i]));
#endif
xr_pow[i] = MUL_F(xr_pow[i],maxfixstep);
#ifdef DUMP_MAXFIXSTEP
printf("xr_pow[%d]*fix = %.8f\n",i,COEF2FLOAT(xr_pow[i]));
#endif
}
QuantizeBand(xr_pow, xi, start, end);
coderInfo->scale_factor[sb] = (int32_t)REAL2INT(MUL_R(faac_log(maxfixstep)-FRAC2REAL_BIT*realconst1,
log_ifqstep) - realconst2)+1;
#ifdef DUMP_MAXFIXSTEP
printf("scale_factor = %d\n", coderInfo->scale_factor[sb]);
#endif
}
#ifdef DUMP_MAXFIXSTEP
exit(1);
#endif
return 0;
}
static int FixNoise(CoderInfo *coderInfo,
const double *xr,
double *xr_pow,
int *xi,
double *xmin,
double *pow43,
double *adj43)
{
int i, sb;
int start, end;
double diffvol;
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 = (int)(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,
adj43);
//printf("\tsfac: %d\n", sfac);
calcdist:
diffvol = 0.0;
for (i = start; i < end; i++)
{
tmp = xi[i];
diffvol += tmp * tmp; // ~x^(3/2)
}
if (diffvol < 1e-6)
diffvol = 1e-6;
tmp = pow(diffvol / (double)(end - start), -0.666);
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,
adj43);
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,
adj43);
goto calcdist;
}
}
}
return 0;
}
