1.4.2.29 DSP_TransformFFT16_setup Function

Creates FFT coefficients for use in the FFT16 function.

Description

void DSP_TransformFFT16_setup(int16c *twiddles, int log2N);

Calculates the N twiddle factors required to operate the FFT16 function. These factors are done in serial fashion, and require considerable processing power. Ideally this function would be run only once prior to an ongoing FFT, and the results held in a buffer.

Preconditions

twiddles must be N in length N is calculated (2^log2N)

Parameters

twiddles pointer to a complex array of factors (int16c)

log2N binary exponent of number of data points (int)

Returns

None.

Remarks

This function is of considerable length and executed in C.

It is recommended it only be called once for any given FFT length in time sensitive applications.

Example

see DSP_TransformFFT16 for example.

C

void  DSP_TransformFFT16_setup (int16c * twiddles , int  log2N );