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#include "config.h"
#include "bformatdec.h"
#include "ambdec.h"
#include "alu.h"
typedef struct BandSplitter {
ALfloat coeff;
ALfloat lp_z1;
ALfloat lp_z2;
ALfloat hp_z1;
} BandSplitter;
static void bandsplit_init(BandSplitter *splitter, ALfloat freq_mult)
{
ALfloat w = freq_mult * 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;
}
static void bandsplit_process(BandSplitter *splitter, ALfloat *restrict hpout, ALfloat *restrict lpout,
const ALfloat *input, ALuint count)
{
ALfloat coeff, d, x;
ALuint i;
coeff = splitter->coeff*0.5f + 0.5f;
for(i = 0;i < count;i++)
{
x = input[i];
d = (x - splitter->lp_z1) * coeff;
x = splitter->lp_z1 + d;
splitter->lp_z1 = x + d;
d = (x - splitter->lp_z2) * coeff;
x = splitter->lp_z2 + d;
splitter->lp_z2 = x + d;
lpout[i] = x;
}
coeff = splitter->coeff;
for(i = 0;i < count;i++)
{
x = input[i];
d = x - coeff*splitter->hp_z1;
x = splitter->hp_z1 + coeff*d;
splitter->hp_z1 = d;
hpout[i] = x - lpout[i];
}
}
static const ALfloat UnitScale[MAX_AMBI_COEFFS] = {
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f
};
static const ALfloat SN3D2N3DScale[MAX_AMBI_COEFFS] = {
1.000000000f, /* ACN 0 (W), sqrt(1) */
1.732050808f, /* ACN 1 (Y), sqrt(3) */
1.732050808f, /* ACN 2 (Z), sqrt(3) */
1.732050808f, /* ACN 3 (X), sqrt(3) */
2.236067978f, /* ACN 4 (V), sqrt(5) */
2.236067978f, /* ACN 5 (T), sqrt(5) */
2.236067978f, /* ACN 6 (R), sqrt(5) */
2.236067978f, /* ACN 7 (S), sqrt(5) */
2.236067978f, /* ACN 8 (U), sqrt(5) */
2.645751311f, /* ACN 9 (Q), sqrt(7) */
2.645751311f, /* ACN 10 (O), sqrt(7) */
2.645751311f, /* ACN 11 (M), sqrt(7) */
2.645751311f, /* ACN 12 (K), sqrt(7) */
2.645751311f, /* ACN 13 (L), sqrt(7) */
2.645751311f, /* ACN 14 (N), sqrt(7) */
2.645751311f, /* ACN 15 (P), sqrt(7) */
};
static const ALfloat FuMa2N3DScale[MAX_AMBI_COEFFS] = {
1.414213562f, /* ACN 0 (W), sqrt(2) */
1.732050808f, /* ACN 1 (Y), sqrt(3) */
1.732050808f, /* ACN 2 (Z), sqrt(3) */
1.732050808f, /* ACN 3 (X), sqrt(3) */
1.936491673f, /* ACN 4 (V), sqrt(15)/2 */
1.936491673f, /* ACN 5 (T), sqrt(15)/2 */
2.236067978f, /* ACN 6 (R), sqrt(5) */
1.936491673f, /* ACN 7 (S), sqrt(15)/2 */
1.936491673f, /* ACN 8 (U), sqrt(15)/2 */
2.091650066f, /* ACN 9 (Q), sqrt(35/8) */
1.972026594f, /* ACN 10 (O), sqrt(35)/3 */
2.231093404f, /* ACN 11 (M), sqrt(224/45) */
2.645751311f, /* ACN 12 (K), sqrt(7) */
2.231093404f, /* ACN 13 (L), sqrt(224/45) */
1.972026594f, /* ACN 14 (N), sqrt(35)/3 */
2.091650066f, /* ACN 15 (P), sqrt(35/8) */
};
/* NOTE: Low-frequency (LF) fields and BandSplitter filters are unused with
* single-band decoding
*/
typedef struct BFormatDec {
alignas(16) ALfloat MatrixHF[MAX_OUTPUT_CHANNELS][MAX_AMBI_COEFFS];
alignas(16) ALfloat MatrixLF[MAX_OUTPUT_CHANNELS][MAX_AMBI_COEFFS];
BandSplitter XOver[MAX_AMBI_COEFFS];
ALfloat (*Samples)[BUFFERSIZE];
/* These two alias into Samples */
ALfloat (*SamplesHF)[BUFFERSIZE];
ALfloat (*SamplesLF)[BUFFERSIZE];
ALuint NumChannels;
ALboolean DualBand;
} BFormatDec;
BFormatDec *bformatdec_alloc()
{
return al_calloc(16, sizeof(BFormatDec));
}
void bformatdec_free(BFormatDec *dec)
{
if(dec)
{
al_free(dec->Samples);
dec->Samples = NULL;
dec->SamplesHF = NULL;
dec->SamplesLF = NULL;
memset(dec, 0, sizeof(*dec));
al_free(dec);
}
}
void bformatdec_reset(BFormatDec *dec, const AmbDecConf *conf, ALuint chancount, ALuint srate, const ALuint chanmap[MAX_OUTPUT_CHANNELS])
{
const ALfloat *coeff_scale = UnitScale;
ALfloat ratio;
ALuint i;
al_free(dec->Samples);
dec->Samples = NULL;
dec->SamplesHF = NULL;
dec->SamplesLF = NULL;
dec->NumChannels = chancount;
dec->Samples = al_calloc(16, dec->NumChannels * conf->FreqBands *
sizeof(dec->Samples[0]));
dec->SamplesHF = dec->Samples;
dec->SamplesLF = dec->SamplesHF + dec->NumChannels;
if(conf->CoeffScale == ADS_SN3D)
coeff_scale = SN3D2N3DScale;
else if(conf->CoeffScale == ADS_FuMa)
coeff_scale = FuMa2N3DScale;
if(conf->FreqBands == 1)
{
dec->DualBand = AL_FALSE;
ratio = 1.0f;
}
else
{
dec->DualBand = AL_TRUE;
ratio = conf->XOverFreq / (ALfloat)srate;
for(i = 0;i < MAX_AMBI_COEFFS;i++)
bandsplit_init(&dec->XOver[i], ratio);
ratio = powf(10.0f, conf->XOverRatio / 40.0f);
memset(dec->MatrixLF, 0, sizeof(dec->MatrixLF));
for(i = 0;i < conf->NumSpeakers;i++)
{
ALuint chan = chanmap[i];
ALuint j, k = 0;
for(j = 0;j < 1;j++)
{
if((conf->ChanMask&(1<<j)))
dec->MatrixLF[chan][j] = conf->LFMatrix[i][k++] / coeff_scale[j] *
conf->LFOrderGain[0] / ratio;
}
for(;j < 4;j++)
{
if((conf->ChanMask&(1<<j)))
dec->MatrixLF[chan][j] = conf->LFMatrix[i][k++] / coeff_scale[j] *
conf->LFOrderGain[1] / ratio;
}
for(;j < 9;j++)
{
if((conf->ChanMask&(1<<j)))
dec->MatrixLF[chan][j] = conf->LFMatrix[i][k++] / coeff_scale[j] *
conf->LFOrderGain[2] / ratio;
}
for(;j < 16;j++)
{
if((conf->ChanMask&(1<<j)))
dec->MatrixLF[chan][j] = conf->LFMatrix[i][k++] / coeff_scale[j] *
conf->LFOrderGain[3] / ratio;
}
}
}
memset(dec->MatrixHF, 0, sizeof(dec->MatrixHF));
for(i = 0;i < conf->NumSpeakers;i++)
{
ALuint chan = chanmap[i];
ALuint j, k = 0;
for(j = 0;j < 1;j++)
{
if((conf->ChanMask&(1<<j)))
dec->MatrixHF[chan][j] = conf->HFMatrix[i][k++] / coeff_scale[j] *
conf->HFOrderGain[0] * ratio;
}
for(;j < 4;j++)
{
if((conf->ChanMask&(1<<j)))
dec->MatrixHF[chan][j] = conf->HFMatrix[i][k++] / coeff_scale[j] *
conf->HFOrderGain[1] * ratio;
}
for(;j < 9;j++)
{
if((conf->ChanMask&(1<<j)))
dec->MatrixHF[chan][j] = conf->HFMatrix[i][k++] / coeff_scale[j] *
conf->HFOrderGain[2] * ratio;
}
for(;j < 16;j++)
{
if((conf->ChanMask&(1<<j)))
dec->MatrixHF[chan][j] = conf->HFMatrix[i][k++] / coeff_scale[j] *
conf->HFOrderGain[3] * ratio;
}
}
}
static void apply_row(ALfloat *out, const ALfloat *mtx, ALfloat (*restrict in)[BUFFERSIZE], ALuint inchans, ALuint todo)
{
ALuint c, i;
for(c = 0;c < inchans;c++)
{
ALfloat gain = mtx[c];
if(!(fabsf(gain) > GAIN_SILENCE_THRESHOLD))
continue;
for(i = 0;i < todo;i++)
out[i] += in[c][i] * gain;
}
}
void bformatdec_process(struct BFormatDec *dec, ALfloat (*restrict OutBuffer)[BUFFERSIZE], ALuint OutChannels, ALfloat (*restrict InSamples)[BUFFERSIZE], ALuint SamplesToDo)
{
ALuint chan, i;
if(dec->DualBand)
{
for(i = 0;i < dec->NumChannels;i++)
bandsplit_process(&dec->XOver[i], dec->SamplesHF[i], dec->SamplesLF[i],
InSamples[i], SamplesToDo);
for(chan = 0;chan < OutChannels;chan++)
{
apply_row(OutBuffer[chan], dec->MatrixHF[chan], dec->SamplesHF,
dec->NumChannels, SamplesToDo);
apply_row(OutBuffer[chan], dec->MatrixLF[chan], dec->SamplesLF,
dec->NumChannels, SamplesToDo);
}
}
else
{
for(chan = 0;chan < OutChannels;chan++)
apply_row(OutBuffer[chan], dec->MatrixHF[chan], InSamples,
dec->NumChannels, SamplesToDo);
}
}
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