Fourier Transform of Random Image

Uniform Random Image

uniform random image Fourier transform magnitude

The DC term was removed from the input image before taking its transform.

Matlab code

inp = rand(256);
imwrite(inp,'uniform_random.jpg');
% input has DC term removed.
% output is magnitude of output
oup = sqrt(psf(inp-mean2(inp)));
imwrite(oup,'uniform_random_transform.jpg');

Normal Random Image

normal random image Fourier transform magnitude

The input image has a mean of 0.5 and standard deviation of 0.1. The mean was subtracted from the image before its Fourier transform was taken.

Matlab code

» inp = randn(256);
» inp = 0.1*inp+0.5;
» std2(inp)

ans = 0.1003

» mean2(inp)

ans =  0.5008

» imhist(inp);
» imshow(inp);
» imwrite(inp,'normal.jpg');
» oup = sqrt(psf(inp-0.5));
» imshow(oup);
» imwrite(oup,'normal_transform.jpg');
» imhist(oup);

Maintained by John Loomis, last updated 16 March 2000