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#include "config.h"
#include "splitter.h"
#include "math_defs.h"
void bandsplit_init(BandSplitter *splitter, ALfloat f0norm)
{
ALfloat w = f0norm * F_TAU;
ALfloat cw = cosf(w);
if(cw > FLT_EPSILON)
splitter->coeff = (sinf(w) - 1.0f) / cw;
else
splitter->coeff = cw * -0.5f;
splitter->lp_z1 = 0.0f;
splitter->lp_z2 = 0.0f;
splitter->hp_z1 = 0.0f;
}
void bandsplit_clear(BandSplitter *splitter)
{
splitter->lp_z1 = 0.0f;
splitter->lp_z2 = 0.0f;
splitter->hp_z1 = 0.0f;
}
void bandsplit_process(BandSplitter *splitter, ALfloat *RESTRICT hpout, ALfloat *RESTRICT lpout,
const ALfloat *input, ALsizei count)
{
ALfloat lp_coeff, hp_coeff, lp_y, hp_y, d;
ALfloat lp_z1, lp_z2, hp_z1;
ALsizei i;
ASSUME(count > 0);
hp_coeff = splitter->coeff;
lp_coeff = splitter->coeff*0.5f + 0.5f;
lp_z1 = splitter->lp_z1;
lp_z2 = splitter->lp_z2;
hp_z1 = splitter->hp_z1;
for(i = 0;i < count;i++)
{
ALfloat in = input[i];
/* Low-pass sample processing. */
d = (in - lp_z1) * lp_coeff;
lp_y = lp_z1 + d;
lp_z1 = lp_y + d;
d = (lp_y - lp_z2) * lp_coeff;
lp_y = lp_z2 + d;
lp_z2 = lp_y + d;
lpout[i] = lp_y;
/* All-pass sample processing. */
hp_y = in*hp_coeff + hp_z1;
hp_z1 = in - hp_y*hp_coeff;
/* High-pass generated from removing low-passed output. */
hpout[i] = hp_y - lp_y;
}
splitter->lp_z1 = lp_z1;
splitter->lp_z2 = lp_z2;
splitter->hp_z1 = hp_z1;
}
void splitterap_init(SplitterAllpass *splitter, ALfloat f0norm)
{
ALfloat w = f0norm * F_TAU;
ALfloat cw = cosf(w);
if(cw > FLT_EPSILON)
splitter->coeff = (sinf(w) - 1.0f) / cw;
else
splitter->coeff = cw * -0.5f;
splitter->z1 = 0.0f;
}
void splitterap_clear(SplitterAllpass *splitter)
{
splitter->z1 = 0.0f;
}
void splitterap_process(SplitterAllpass *splitter, ALfloat *RESTRICT samples, ALsizei count)
{
ALfloat coeff, in, out;
ALfloat z1;
ALsizei i;
ASSUME(count > 0);
coeff = splitter->coeff;
z1 = splitter->z1;
for(i = 0;i < count;i++)
{
in = samples[i];
out = in*coeff + z1;
z1 = in - out*coeff;
samples[i] = out;
}
splitter->z1 = z1;
}
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