Comment Re:Wish I could understand the details of FFTs (Score 1) 271
It is actually quite simple provided you have at least some basic math skills. Don't try to wrap your head around the math involved just yet. Just do this:
1) Have a look at http://en.wikipedia.org/wiki/Fourier_transform and only look at Definition and Introduction.
2) Get some tool like Matlab or Octave (the last one is OSS)
3) Generate a pure sine wave signal and put that through the formula's you found in 1). You should get a single spike in your results
4) Now add a second sine wave with a different frequency to the first signal. and put that signal through the same formulas. You should find two spikes.
5) Try experimenting with this, adding signals and experiencing how the amplitude and frequency impacts the spike height and position.
When you have a feeling for this, THAT is the time to read the entire article. You will find it easier to understand.
You now have a reasonable understanding of the Fourier Transform. The Fast Fourier Transform or classic FFT is no more than some mathematical trick to make these calculations faster and actually it has it's drawbacks, like your nr of sample must be a power of 2 and some other stuff I won't go into here, although these are acceptable in most practical cases. This new FFT transform seems to be a lossy variant of FFT which will impact the resulting signal, negating the contribution of frequency area's with low energy content. It could be especially useful in situation where that loss of information is acceptable as it is in sound and video to some degree. However, I did not really read up on this new method so I could be off the mark...