void zvmul(const float* real1P, const float* imag1P, const float* real2P, const float* imag2P, float* realDestP, float* imagDestP, size_t framesToProcess)
{
DSPSplitComplex sc1;
DSPSplitComplex sc2;
DSPSplitComplex dest;
sc1.realp = const_cast<float*>(real1P);
sc1.imagp = const_cast<float*>(imag1P);
sc2.realp = const_cast<float*>(real2P);
sc2.imagp = const_cast<float*>(imag2P);
dest.realp = realDestP;
dest.imagp = imagDestP;
#if defined(__ppc__) || defined(__i386__)
::zvmul(&sc1, 1, &sc2, 1, &dest, 1, framesToProcess, 1);
#else
vDSP_zvmul(&sc1, 1, &sc2, 1, &dest, 1, framesToProcess, 1);
#endif
}
void FFTFrame::multiply(const FFTFrame& frame)
{
FFTFrame& frame1 = *this;
const FFTFrame& frame2 = frame;
float* realP1 = frame1.realData();
float* imagP1 = frame1.imagData();
const float* realP2 = frame2.realData();
const float* imagP2 = frame2.imagData();
// Scale accounts for vecLib's peculiar scaling
// This ensures the right scaling all the way back to inverse FFT
float scale = 0.5f;
// Multiply packed DC/nyquist component
realP1[0] *= scale * realP2[0];
imagP1[0] *= scale * imagP2[0];
// Multiply the rest, skipping packed DC/Nyquist components
DSPSplitComplex sc1 = frame1.dspSplitComplex();
sc1.realp++;
sc1.imagp++;
DSPSplitComplex sc2 = frame2.dspSplitComplex();
sc2.realp++;
sc2.imagp++;
unsigned halfSize = m_FFTSize / 2;
// Complex multiply
vDSP_zvmul(&sc1, 1, &sc2, 1, &sc1, 1, halfSize - 1, 1 /* normal multiplication */);
// We've previously scaled the packed part, now scale the rest.....
vDSP_vsmul(sc1.realp, 1, &scale, sc1.realp, 1, halfSize - 1);
vDSP_vsmul(sc1.imagp, 1, &scale, sc1.imagp, 1, halfSize - 1);
}
