CMSIS-DSP: arm_rfft_instance_q15 Struct Reference

| CMSIS-DSP Version 1.7.0 CMSIS DSP Software Library

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arm_rfft_instance_q15 Struct Reference

Instance structure for the Q15 RFFT/RIFFT function.

## Data Fields
uint32_t | fftLenReal
uint8_t | ifftFlagR
uint8_t | bitReverseFlagR
uint32_t | twidCoefRModifier
const q15_t * | pTwiddleAReal
const q15_t * | pTwiddleBReal
const arm_cfft_instance_q15 * | pCfft

## Field Documentation

uint8_t arm_rfft_instance_q15::bitReverseFlagR

flag that enables (bitReverseFlagR=1) or disables (bitReverseFlagR=0) bit reversal of output.

uint32_t arm_rfft_instance_q15::fftLenReal

length of the real FFT.

uint8_t arm_rfft_instance_q15::ifftFlagR

flag that selects forward (ifftFlagR=0) or inverse (ifftFlagR=1) transform.

const arm_cfft_instance_q15* arm_rfft_instance_q15::pCfft

points to the complex FFT instance.

const q15_t* arm_rfft_instance_q15::pTwiddleAReal

points to the real twiddle factor table.

const q15_t* arm_rfft_instance_q15::pTwiddleBReal

points to the imag twiddle factor table.

uint32_t arm_rfft_instance_q15::twidCoefRModifier

twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table.