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23 lines
643 B
23 lines
643 B
8 years ago
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### Output of FFT:
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```
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{[DC,NY],C[1],C[2],...,C[n/2]}
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```
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### On a sample basis
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Let ps stand for "per sample"
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``` C[1] ``` gives the ```1/N``` ps coefficient
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``` C[2] ``` gives the ```2/N``` ps coefficient
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``` C[N/2] ``` gives the ```1/2``` ps coefficient
### In seconds
Let ```f``` (=44100) be the samplerate. Then:
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``` C[1] ``` gives the ```f/N``` hz coefficient
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``` C[2] ``` gives the ```2f/N``` hz coefficient
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``` C[N/2] ``` gives the ```f/2``` hz coefficient
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### From herz to position
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Let ```h``` be some frequency. Then from the above we see that for ``` m := Nh/f ``` we get the ```mf/N = h``` hz coefficient in ``` C[m]```.
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