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# FFT4

> FFT4

# FFT4

Fast Fourier Transform with four samples.

## Syntax

```cpp theme={null}
void FFT4(  
         XMVECTOR* __restrict pReal,  
         XMVECTOR* __restrict pImaginary,  
         const size_t uCount= 1  
)  
```

### Parameters

*pReal*   \_Inout\_updates\_(uCount)\
Type: XMVECTOR\* \_\_restrict

Real components of the FFT. Must have at least *uCount* elements.

*pImaginary*   \_Inout\_updates\_(uCount)\
Type: XMVECTOR\* \_\_restrict

Imaginary components of the FFT. Must have at least *uCount* elements.

*uCount*   \_In\_\
Type: size\_t

Number of FFT iterations.

### Return value

Type: void

None.

## Remarks

For FFTs with a number of samples that are less than or equal to 16, use [FFT16](/reference/audio/xdsp/functions/fft16), [FFT8](/reference/audio/xdsp/functions/fft8), or [FFT4](/reference/audio/xdsp/functions/fft4).

All buffer parameters must be 16-byte aligned. Audio data must be FLOAT32 mono.

## Requirements

**Header:** xdsp.h

**Supported platforms:** XBOX One family consoles and XBOX Series consoles

## See also

[xdsp](/reference/audio/xdsp/xdsp_members)


## Related topics

- [FFT](/reference/audio/xdsp/functions/fft.md)
- [FFT16](/reference/audio/xdsp/functions/fft16.md)
- [FFT8](/reference/audio/xdsp/functions/fft8.md)
- [FFTInitializeUnityTable](/reference/audio/xdsp/functions/fftinitializeunitytable.md)
- [ButterflyDIT4_1](/reference/audio/xdsp/functions/butterflydit4_1.md)