nrf_dsp_cfft_twiddle_factors_i16()

uint16_t nrf_dsp_cfft_twiddle_factors_i16	(	int16_t *	p_twiddle_cfft,
		uint16_t	fft_len )

#include <include/nrf_edgeai/dsp/transform/fft/nrf_dsp_fft_i16.h>

Generate fixed-point 16 bit complex twiddle factors buffer.

Parameters

[out]	p_twiddle_cfft	Output complex twiddle factors buffer, the output buffer should be 3*fft_len/2 in length the twiddle factors will be written in interleaved fashion: (cos0,sin0,cos1,sin1,..., cosN,sinN),
[in]	fft_len	FFT length for which complex twiddle factors table will be generated, should be in power of 2

Returns

Number of twiddle factors in the output buffer, if fft_len is not power of 2, returns 0