# arm_dct4_instance_q31 Struct Reference

Instance structure for the Q31 DCT4/IDCT4 function. More...

`#include <arm_math.h>`

## Data Fields

uint16_t | N
uint16_t | Nby2
q31_t | normalize
q31_t * | pTwiddle
q31_t * | pCosFactor
arm_rfft_instance_q31 * | pRfft
arm_cfft_radix4_instance_q31 * | pCfft

## Detailed Description

Instance structure for the Q31 DCT4/IDCT4 function.

Definition at line 2341 of file arm_math.h.

## Field Documentation

uint16_t arm_dct4_instance_q31::N

length of the DCT4.

Definition at line 2343 of file arm_math.h.

uint16_t arm_dct4_instance_q31::Nby2

half of the length of the DCT4.

Definition at line 2344 of file arm_math.h.

q31_t arm_dct4_instance_q31::normalize

normalizing factor.

Definition at line 2345 of file arm_math.h.

q31_t* arm_dct4_instance_q31::pTwiddle

points to the twiddle factor table.

Definition at line 2346 of file arm_math.h.

q31_t* arm_dct4_instance_q31::pCosFactor

points to the cosFactor table.

Definition at line 2347 of file arm_math.h.

arm_rfft_instance_q31* arm_dct4_instance_q31::pRfft

points to the real FFT instance.

Definition at line 2348 of file arm_math.h.

arm_cfft_radix4_instance_q31* arm_dct4_instance_q31::pCfft

points to the complex FFT instance.

Definition at line 2349 of file arm_math.h.

The documentation for this struct was generated from the following file:

- arm_math.h

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