Module microfft::real

FFT on real inputs (RFFT)

This implementation takes advantage of the symmetry properties of the FFT to compute an N-point RFFT by internally invoking an N/2-point CFFT, roughly doubling the computation speed compared to used a full N-point CFFT.

The produced output is the first half out the output returned by the corresponding N-point CFFT, i.e. the real DC value and N/2 - 1 positive-frequency terms. The negative-frequency terms are not computed, since they can be calculated from the positive-frequency terms and are therefore redundant.

Functions

rfft_2	Perform an in-place 2-point RFFT.
rfft_4	Perform an in-place 4-point RFFT.
rfft_8	Perform an in-place 8-point RFFT.
rfft_16	Perform an in-place 16-point RFFT.
rfft_32	Perform an in-place 32-point RFFT.
rfft_64	Perform an in-place 64-point RFFT.
rfft_128	Perform an in-place 128-point RFFT.
rfft_256	Perform an in-place 256-point RFFT.
rfft_512	Perform an in-place 512-point RFFT.
rfft_1024	Perform an in-place 1024-point RFFT.
rfft_2048	Perform an in-place 2048-point RFFT.
rfft_4096	Perform an in-place 4096-point RFFT.