# FCONV2D

## Purpose:

Computes the 2D convolution of two arrays
using the FFT method.

## Syntax:

FCONV2D(array1, array2)

array1 |
- |
An array. |

array2 |
- |
An array. |

## Returns:

An array, the convolved result.

## Example:

W1: randn(30)

W2: randn(30)

W3: conv2d(w1, w2)

W4: fconv2d(w1, w2)

Performs the 2D convolution of two random
arrays. W3 performs direct convolution in the time domain and W4 performs
the same convolution using the FFT method.

## Remarks:

For an image *I*[*x, y*]
and a kernel function *f*[*x, y*],
the 2D linear convolution *c*[*x, y*]
is defined as:

FCONV2D performs the two-dimensional linear convolution in the frequency
domain by computing the 2D FFTs of the input arrays. This method is usually
faster than CONV2D for when both
inputs are relatively large arrays.

See CONV2D
for a time domain implementation.

See IMCONV for
image convolution that handles individual RGB components.

## See Also:

CONV

CONV2D

FCONV

FFT2

IMCONV