void compute_ath( lame_global_flags *gfp, FLOAT8 ATH_l[], FLOAT8 ATH_s[] )
{
lame_internal_flags *gfc = gfp->internal_flags;
int sfb, i, start, end;
FLOAT8 ATH_f;
FLOAT8 samp_freq = gfp->out_samplerate;
for (sfb = 0; sfb < SBMAX_l; sfb++) {
start = gfc->scalefac_band.l[ sfb ];
end = gfc->scalefac_band.l[ sfb+1 ];
ATH_l[sfb]=FLOAT8_MAX;
for (i = start ; i < end; i++) {
FLOAT8 freq = i*samp_freq/(2*576);
ATH_f = ATHmdct( gfp, freq ); /* freq in kHz */
ATH_l[sfb] = Min( ATH_l[sfb], ATH_f );
}
}
for (sfb = 0; sfb < SBMAX_s; sfb++){
start = gfc->scalefac_band.s[ sfb ];
end = gfc->scalefac_band.s[ sfb+1 ];
ATH_s[sfb] = FLOAT8_MAX;
for (i = start ; i < end; i++) {
FLOAT8 freq = i*samp_freq/(2*192);
ATH_f = ATHmdct( gfp, freq ); /* freq in kHz */
ATH_s[sfb] = Min( ATH_s[sfb], ATH_f );
}
}
/* no-ATH mode:
* reduce ATH to -200 dB
*/
if (gfp->noATH) {
for (sfb = 0; sfb < SBMAX_l; sfb++) {
ATH_l[sfb] = 1E-37;
}
for (sfb = 0; sfb < SBMAX_s; sfb++) {
ATH_s[sfb] = 1E-37;
}
}
/* work in progress, don't rely on it too much
*/
gfc->ATH-> floor = 10. * log10( ATHmdct( gfp, -1. ) );
/*
{ FLOAT8 g=10000, t=1e30, x;
for ( f = 100; f < 10000; f++ ) {
x = ATHmdct( gfp, f );
if ( t > x ) t = x, g = f;
}
printf("min=%g\n", g);
}*/
}
static void
compute_ath(lame_internal_flags const* gfc)
{
SessionConfig_t const *const cfg = &gfc->cfg;
FLOAT *const ATH_l = gfc->ATH->l;
FLOAT *const ATH_psfb21 = gfc->ATH->psfb21;
FLOAT *const ATH_s = gfc->ATH->s;
FLOAT *const ATH_psfb12 = gfc->ATH->psfb12;
int sfb, i, start, end;
FLOAT ATH_f;
FLOAT const samp_freq = cfg->samplerate_out;
for (sfb = 0; sfb < SBMAX_l; sfb++) {
start = gfc->scalefac_band.l[sfb];
end = gfc->scalefac_band.l[sfb + 1];
ATH_l[sfb] = FLOAT_MAX;
for (i = start; i < end; i++) {
FLOAT const freq = i * samp_freq / (2 * 576);
ATH_f = ATHmdct(cfg, freq); /* freq in kHz */
ATH_l[sfb] = Min(ATH_l[sfb], ATH_f);
}
}
for (sfb = 0; sfb < PSFB21; sfb++) {
start = gfc->scalefac_band.psfb21[sfb];
end = gfc->scalefac_band.psfb21[sfb + 1];
ATH_psfb21[sfb] = FLOAT_MAX;
for (i = start; i < end; i++) {
FLOAT const freq = i * samp_freq / (2 * 576);
ATH_f = ATHmdct(cfg, freq); /* freq in kHz */
ATH_psfb21[sfb] = Min(ATH_psfb21[sfb], ATH_f);
}
}
for (sfb = 0; sfb < SBMAX_s; sfb++) {
start = gfc->scalefac_band.s[sfb];
end = gfc->scalefac_band.s[sfb + 1];
ATH_s[sfb] = FLOAT_MAX;
for (i = start; i < end; i++) {
FLOAT const freq = i * samp_freq / (2 * 192);
ATH_f = ATHmdct(cfg, freq); /* freq in kHz */
ATH_s[sfb] = Min(ATH_s[sfb], ATH_f);
}
ATH_s[sfb] *= (gfc->scalefac_band.s[sfb + 1] - gfc->scalefac_band.s[sfb]);
}
for (sfb = 0; sfb < PSFB12; sfb++) {
start = gfc->scalefac_band.psfb12[sfb];
end = gfc->scalefac_band.psfb12[sfb + 1];
ATH_psfb12[sfb] = FLOAT_MAX;
for (i = start; i < end; i++) {
FLOAT const freq = i * samp_freq / (2 * 192);
ATH_f = ATHmdct(cfg, freq); /* freq in kHz */
ATH_psfb12[sfb] = Min(ATH_psfb12[sfb], ATH_f);
}
/*not sure about the following */
ATH_psfb12[sfb] *= (gfc->scalefac_band.s[13] - gfc->scalefac_band.s[12]);
}
/* no-ATH mode:
* reduce ATH to -200 dB
*/
if (cfg->noATH) {
for (sfb = 0; sfb < SBMAX_l; sfb++) {
ATH_l[sfb] = 1E-20;
}
for (sfb = 0; sfb < PSFB21; sfb++) {
ATH_psfb21[sfb] = 1E-20;
}
for (sfb = 0; sfb < SBMAX_s; sfb++) {
ATH_s[sfb] = 1E-20;
}
for (sfb = 0; sfb < PSFB12; sfb++) {
ATH_psfb12[sfb] = 1E-20;
}
}
/* work in progress, don't rely on it too much
*/
gfc->ATH->floor = 10. * log10(ATHmdct(cfg, -1.));
/*
{ FLOAT g=10000, t=1e30, x;
for ( f = 100; f < 10000; f++ ) {
x = ATHmdct( cfg, f );
if ( t > x ) t = x, g = f;
}
printf("min=%g\n", g);
} */
}