static unsafe void cubic_spline(stage_t p, fifo_t output_fifo)
{
int i, num_in = p.occupancy;
int max_num_out = 1 + (int)(num_in * p.out_in_ratio);
int output_offs = output_fifo.reserve(max_num_out);
fixed(byte *pinput = &p.fifo.data[p.offset], poutput = &output_fifo.data[output_offs])
{
double *input = (double *)pinput;
double *output = (double *)poutput;
for (i = 0; (p.at >> 32) < num_in; ++i, p.at += p.step)
{
double *s = input + (p.at >> 32);
double x = (p.at & 0xffffffff) * (1 / MULT32);
double b = 0.5 * (s[1] + s[-1]) - *s, a = (1 / 6.0) * (s[2] - s[1] + s[-1] - *s - 4 * b);
double c = s[1] - *s - a - b;
output[i] = ((a * x + b) * x + c) * x + *s;
}
}
//assert(max_num_out - i >= 0);
output_fifo.trim_by(max_num_out - i);
p.fifo.read((int)(p.at >> 32), null);
p.at &= 0xffffffff;
}
static unsafe void double_sample(stage_t p, fifo_t output_fifo)
{
int num_in = Math.Max(0, p.fifo.occupancy);
dft_filter_t f = p.shared.half_band[1];
int overlap = f.num_taps - 1;
while (num_in > f.dft_length >> 1)
{
int input_offs = p.fifo.offset;
p.fifo.read((f.dft_length - overlap) >> 1, null);
num_in -= (f.dft_length - overlap) >> 1;
int output_offs = output_fifo.reserve(f.dft_length);
output_fifo.trim_by(overlap);
fixed(byte *pinput = &p.fifo.data[input_offs])
fixed(byte *poutput = &output_fifo.data[output_offs])
fixed(double *lsx_fft_sc = p.shared.info.lsx_fft_sc)
fixed(int *lsx_fft_br = p.shared.info.lsx_fft_br)
{
double *input = (double *)pinput;
double *output = (double *)poutput;
for (int j = 0, i = 0; i < f.dft_length; ++j, i += 2)
{
output[i] = input[j];
output[i + 1] = 0;
}
SOXFft.rdft(f.dft_length, 1, output, lsx_fft_br, lsx_fft_sc);
output[0] *= f.coefs[0];
output[1] *= f.coefs[1];
for (int i = 2; i < f.dft_length; i += 2)
{
double tmp = output[i];
output[i] = f.coefs[i] * tmp - f.coefs[i + 1] * output[i + 1];
output[i + 1] = f.coefs[i + 1] * tmp + f.coefs[i] * output[i + 1];
}
SOXFft.rdft(f.dft_length, -1, output, lsx_fft_br, lsx_fft_sc);
}
}
}
static unsafe void half_sample(stage_t p, fifo_t output_fifo)
{
int num_in = Math.Max(0, p.fifo.occupancy);
dft_filter_t f = p.shared.half_band[p.which];
int overlap = f.num_taps - 1;
while (num_in >= f.dft_length)
{
int input_offs = p.fifo.offset;
p.fifo.read(f.dft_length - overlap, null);
num_in -= f.dft_length - overlap;
int output_offs = output_fifo.reserve(f.dft_length);
output_fifo.trim_by((f.dft_length + overlap) >> 1);
Buffer.BlockCopy(p.fifo.data, input_offs, output_fifo.data, output_offs, f.dft_length * sizeof(double));
fixed(byte *poutput = &output_fifo.data[output_offs])
fixed(double *lsx_fft_sc = p.shared.info.lsx_fft_sc)
fixed(int *lsx_fft_br = p.shared.info.lsx_fft_br)
{
double *output = (double *)poutput;
SOXFft.rdft(f.dft_length, 1, output, lsx_fft_br, lsx_fft_sc);
output[0] *= f.coefs[0];
output[1] *= f.coefs[1];
for (int i = 2; i < f.dft_length; i += 2)
{
double tmp = output[i];
output[i] = f.coefs[i] * tmp - f.coefs[i + 1] * output[i + 1];
output[i + 1] = f.coefs[i + 1] * tmp + f.coefs[i] * output[i + 1];
}
SOXFft.rdft(f.dft_length, -1, output, lsx_fft_br, lsx_fft_sc);
for (int j = 1, i = 2; i < f.dft_length - overlap; ++j, i += 2)
{
output[j] = output[i];
}
}
}
}
static unsafe void cubic_spline(stage_t p, fifo_t output_fifo)
{
int i, num_in = p.occupancy;
int max_num_out = 1 + (int)(num_in * p.out_in_ratio);
int output_offs = output_fifo.reserve(max_num_out);
fixed (byte* pinput = &p.fifo.data[p.offset], poutput = &output_fifo.data[output_offs])
{
double* input = (double*)pinput;
double* output = (double*)poutput;
for (i = 0; (p.at >> 32) < num_in; ++i, p.at += p.step)
{
double* s = input + (p.at >> 32);
double x = (p.at & 0xffffffff) * (1 / MULT32);
double b = 0.5 * (s[1] + s[-1]) - *s, a = (1 / 6.0) * (s[2] - s[1] + s[-1] - *s - 4 * b);
double c = s[1] - *s - a - b;
output[i] = ((a * x + b) * x + c) * x + *s;
}
}
//assert(max_num_out - i >= 0);
output_fifo.trim_by(max_num_out - i);
p.fifo.read((int)(p.at >> 32), null);
p.at &= 0xffffffff;
}
static unsafe void double_sample(stage_t p, fifo_t output_fifo)
{
int num_in = Math.Max(0, p.fifo.occupancy);
dft_filter_t f = p.shared.half_band[1];
int overlap = f.num_taps - 1;
while (num_in > f.dft_length >> 1)
{
int input_offs = p.fifo.offset;
p.fifo.read((f.dft_length - overlap) >> 1, null);
num_in -= (f.dft_length - overlap) >> 1;
int output_offs = output_fifo.reserve(f.dft_length);
output_fifo.trim_by(overlap);
fixed (byte* pinput = &p.fifo.data[input_offs])
fixed (byte* poutput = &output_fifo.data[output_offs])
fixed (double* lsx_fft_sc = p.shared.info.lsx_fft_sc)
fixed (int* lsx_fft_br = p.shared.info.lsx_fft_br)
{
double* input = (double*)pinput;
double* output = (double*)poutput;
for (int j = 0, i = 0; i < f.dft_length; ++j, i += 2)
{
output[i] = input[j];
output[i + 1] = 0;
}
SOXFft.rdft(f.dft_length, 1, output, lsx_fft_br, lsx_fft_sc);
output[0] *= f.coefs[0];
output[1] *= f.coefs[1];
for (int i = 2; i < f.dft_length; i += 2)
{
double tmp = output[i];
output[i] = f.coefs[i] * tmp - f.coefs[i + 1] * output[i + 1];
output[i + 1] = f.coefs[i + 1] * tmp + f.coefs[i] * output[i + 1];
}
SOXFft.rdft(f.dft_length, -1, output, lsx_fft_br, lsx_fft_sc);
}
}
}
static unsafe void half_sample(stage_t p, fifo_t output_fifo)
{
int num_in = Math.Max(0, p.fifo.occupancy);
dft_filter_t f = p.shared.half_band[p.which];
int overlap = f.num_taps - 1;
while (num_in >= f.dft_length)
{
int input_offs = p.fifo.offset;
p.fifo.read(f.dft_length - overlap, null);
num_in -= f.dft_length - overlap;
int output_offs = output_fifo.reserve(f.dft_length);
output_fifo.trim_by((f.dft_length + overlap) >> 1);
Buffer.BlockCopy(p.fifo.data, input_offs, output_fifo.data, output_offs, f.dft_length * sizeof(double));
fixed (byte* poutput = &output_fifo.data[output_offs])
fixed (double* lsx_fft_sc = p.shared.info.lsx_fft_sc)
fixed (int* lsx_fft_br = p.shared.info.lsx_fft_br)
{
double* output = (double*)poutput;
SOXFft.rdft(f.dft_length, 1, output, lsx_fft_br, lsx_fft_sc);
output[0] *= f.coefs[0];
output[1] *= f.coefs[1];
for (int i = 2; i < f.dft_length; i += 2)
{
double tmp = output[i];
output[i] = f.coefs[i] * tmp - f.coefs[i + 1] * output[i + 1];
output[i + 1] = f.coefs[i + 1] * tmp + f.coefs[i] * output[i + 1];
}
SOXFft.rdft(f.dft_length, -1, output, lsx_fft_br, lsx_fft_sc);
for (int j = 1, i = 2; i < f.dft_length - overlap; ++j, i += 2)
output[j] = output[i];
}
}
}