After doing two FFTs, how can you tell how similar the results are? For example, lets take a look at these FFT results:
- Blue (left top corner) shows the ideal signal.
- Green (right top corner) shows a signal that should be detected as similar.
- Red (left bottom corner) shows a signal that should be detected as different.
I'm looking for a function, that takes two arrays with fft results and returns a number between 0.0 and 1.0, depending on how similar the two arrays of input values are. Is there something like this already available in a C# library? If not, how would you calculate this? What's the math behind it?
Your help is much appreciated. Thank you.