CMSIS-DSP  
CMSIS DSP Software Library
Deprecated Real FFT Functions

Functions

void arm_rfft_f32 (const arm_rfft_instance_f32 *S, float32_t *pSrc, float32_t *pDst)
 Processing function for the floating-point RFFT/RIFFT. Source buffer is modified by this function. More...
 
arm_status arm_rfft_init_f32 (arm_rfft_instance_f32 *S, arm_cfft_radix4_instance_f32 *S_CFFT, uint32_t fftLenReal, uint32_t ifftFlagR, uint32_t bitReverseFlag)
 Initialization function for the floating-point RFFT/RIFFT. More...
 

Description

Function Documentation

◆ arm_rfft_f32()

void arm_rfft_f32 ( const arm_rfft_instance_f32 S,
float32_t pSrc,
float32_t pDst 
)
Deprecated:
Do not use this function. It has been superceded by arm_rfft_fast_f32 and will be removed in the future.
Parameters
[in]Spoints to an instance of the floating-point RFFT/RIFFT structure
[in]pSrcpoints to the input buffer
[out]pDstpoints to the output buffer
Returns
none

◆ arm_rfft_init_f32()

arm_status arm_rfft_init_f32 ( arm_rfft_instance_f32 S,
arm_cfft_radix4_instance_f32 S_CFFT,
uint32_t  fftLenReal,
uint32_t  ifftFlagR,
uint32_t  bitReverseFlag 
)
Deprecated:
Do not use this function. It has been superceded by arm_rfft_fast_init_f32 and will be removed in the future.
Parameters
[in,out]Spoints to an instance of the floating-point RFFT/RIFFT structure
[in,out]S_CFFTpoints to an instance of the floating-point CFFT/CIFFT structure
[in]fftLenReallength of the FFT.
[in]ifftFlagRflag that selects transform direction
  • value = 0: forward transform
  • value = 1: inverse transform
[in]bitReverseFlagflag that enables / disables bit reversal of output
  • value = 0: disables bit reversal of output
  • value = 1: enables bit reversal of output
Returns
execution status
Description
The parameter fftLenRealspecifies length of RFFT/RIFFT Process. Supported FFT Lengths are 128, 512, 2048.
The parameter ifftFlagR controls whether a forward or inverse transform is computed. Set(=1) ifftFlagR to calculate RIFFT, otherwise RFFT is calculated.
The parameter bitReverseFlag controls whether output is in normal order or bit reversed order. Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order.
This function also initializes Twiddle factor table.