FFT_CVIP

fft_cvip() - performs Fast Fourier Transform.

Contents

SYNTAX

spect = fft_cvip( input_img, block_size )

Input parameters include:

Output parameters include:

DESCRIPTION

This function computes the fourier transform of the input image. The argument block_size is usually given empty brackets [] so that the function handles the zero padding itself. Any other value for block_size results in dividing the area of the image into squares of size block_size and taking the fourier of the small windows.

REFERENCE

1. Scott E Umbaugh. DIGITAL IMAGE PROCESSING AND ANALYSIS: Applications with MATLAB and CVIPtools, 3rd Edition.

EXAMPLE

Read image

 input_img = imread('Car.bmp');

% Block size

 block_size = [];

% Call function

 spect = fft_cvip( input_img, block_size );

% use abs to compute the magnitude (handling imaginary) and use log to brighten display

 S2=log(1+abs(spect));

 S2 = remap_cvip(S2);

% Display input image

 figure; imshow(input_img);title('Input Image');

% Display output image

 figure; imshow(S2,[]);title('Output FFT Image');

CREDITS

Author: Mehrdad Alvandipour, March 2017
Copyright © 2017-2018 Scott E Umbaugh
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