3 Apr
2006
3 Apr
'06
9:20 p.m.
Hi,
Has anyone implemented cross correlation in PD using rifft~? I am confident with performing cross correlation in the time domain, but am a little confused about how the equivalent operation can be conducted using FFTs. So far I understand the algorithm to be:
- Zero pad the signal vectors to twice the vector size
- Take their ffts: fft(x) fft(y)
- Take the complex conjugate of fft(x) and multiply this by fft(y)
- Take the inverse fft of the result.
Whatever I try doesn't seem to give the correct output. In particular - I am unsure of step 3 above. Can anyone give some clarification or an example patch.
TIA,
Jamie