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A comment on Fourier Transforms – The Math Trick Behind MP3s, JPEGs, and Homer Simpson’s Face. Parent comment

Re:Fourier Transforms – The Math Trick Behind MP3s, JPEGs, a... by taejo on Wednesday November 06, 2013 @02:11PM (#6684732)
> This is actually the exact same number of numbers as in the time-domain series.

In a way, it's twice as many, since they have both real and imaginary components.

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Re:Fourier Transforms – The Math Trick Behind MP3s, JPEGs, a... by kkjkok on Wednesday November 06, 2013 @03:17PM (#6685201)
Nope - the amount of numbers is in fact identical. The discrete Fourier transform has redundant information in bins above NFFT/2 (where NFFT is the size of the transform/number of samples in the signal) for purely real valued input. This means the "number of numbers" is the same - NFFT/2 bins of necessary complex values after transformation, versus NFFT real values in the original series.
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Re:Fourier Transforms – The Math Trick Behind MP3s, JPEGs, a... by taejo on Monday November 11, 2013 @12:12PM (#6712628)
Ah yeah, forgot about that. Thank you.
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