Error_t
BiquadFilterUpdateKernelD(BiquadFilterD *filter,
const double *bCoeff,
const double *aCoeff)
{
CopyBufferD(filter->b, bCoeff, 3);
CopyBufferD(filter->a, aCoeff, 2);
return NOERR;
}
TEST(DSPDouble, TestCopyBuffer)
{
double out[10];
CopyBufferD(out, onesD, 10);
for (unsigned i = 0; i < 10; ++i)
{
ASSERT_DOUBLE_EQ(onesD[i], out[i]);
}
}
BiquadFilterD*
BiquadFilterInitD(const double *bCoeff, const double *aCoeff)
{
// Allocate Memory
BiquadFilterD* filter = (BiquadFilterD*)malloc(sizeof(BiquadFilterD));
if (filter)
{
// Initialize Buffers
CopyBufferD(filter->b, bCoeff, 3);
CopyBufferD(filter->a, aCoeff, 2);
ClearBufferD(filter->x, 2);
ClearBufferD(filter->y, 2);
ClearBufferD(filter->w, 2);
}
return filter;
}
Error_t
BiquadFilterProcessD(BiquadFilterD *filter,
double *outBuffer,
const double *inBuffer,
unsigned n_samples)
{
#ifdef __APPLE__
// Use accelerate if we have it
double coeffs[5] = {
filter->b[0], filter->b[1], filter->b[2],
filter->a[0], filter->a[1]
};
double temp_in[n_samples + 2];
double temp_out[n_samples + 2];
// Put filter overlaps into beginning of input and output vectors
cblas_dcopy(2, filter->x, 1, temp_in, 1);
cblas_dcopy(2, filter->y, 1, temp_out, 1);
cblas_dcopy(n_samples, inBuffer, 1, (temp_in + 2), 1);
// Process
vDSP_deq22D(temp_in, 1, coeffs, temp_out, 1, n_samples);
// Write overlaps to filter x and y arrays
cblas_dcopy(2, (temp_in + n_samples), 1, filter->x, 1);
cblas_dcopy(2, (temp_out + n_samples), 1, filter->y, 1);
// Write output
cblas_dcopy(n_samples, (temp_out + 2), 1, outBuffer, 1);
#else
double buffer[n_samples];
for (unsigned buffer_idx = 0; buffer_idx < n_samples; ++buffer_idx)
{
// DF-II Implementation
buffer[buffer_idx] = filter->b[0] * inBuffer[buffer_idx] + filter->w[0];
filter->w[0] = filter->b[1] * inBuffer[buffer_idx] - filter->a[0] * \
buffer[buffer_idx] + filter->w[1];
filter->w[1] = filter->b[2] * inBuffer[buffer_idx] - filter->a[1] * \
buffer[buffer_idx];
}
// Write output
CopyBufferD(outBuffer, buffer, n_samples);
#endif
return NOERR;
}
