Question

I am a student that is studying for matlab.

==================================================================

[Question]

Switching magnitude and phase information between two input images

 load two different input images

 And compare the results of switching the magnitude and phase information of the given inputs.

==================================================================

Reference 1 : Internet users

Reference 2 : http://paeton.tistory.com/15

==================================================================

My answer :

cm=imread('image1.bmp');
figure, imshow('image1.bmp');

cf=fftshift(fft2(cm));
g1=mat2gray(fspecial('gaussian',480,10));
cg1=cf.*g1;
figure,fftshow(cg1,'log');
cgi1=ifft2(cg1);
fftshow(cgi1,'abs');

cf=fftshift(fft2(cm));
g1=mat2gray(fspecial('gaussian',480,50));
cg1=cf.*g1;
figure,fftshow(cg1,'log');
cgi1=ifft2(cg1);
fftshow(cgi1,'abs');

==================================================================

I submit the answer to the teacher, but is wrong.

From it's been two months, but not everyone can give the answer.

I do not know how to solve this problem.

Please help me. Phase and Magnitude to switch the source code, please.

Was it helpful?

Solution

Oh... I feel so sorry for you.
You should be answering your homework questions by yourself!

function I_must_understand_this_code_before_I_submit_my_homework( )

% read images
im{1} = im2double( imread( 'image1.bmp' ) );
im{2} = im2double( imread( 'image2.bmp' ) );
assert( all( size(im{1}) == size(im{2}) ), 'images must have same size' );

% FFT - separate magnitude and phase no fftshift
mag = cell(1,2);
phz = cell(1,2);
for ii=1:2
    I = zeros( size(im{ii}) );
    for c = 1:size(im{ii},3) % for color images
        I(:,:,c) = fft2( im{ii}(:,:,c) );
    end
    mag{ii} = abs( I ); % magnitude of fft
    phz{ii} = angle( I ); % phase
end

% combine (still in Fourier domain)
C{1} = mag{1}.*exp( j * phz{2} ); % mag of first with phase of second
C{2} = mag{2}.*exp( j * phz{1} ); % mag of second with phase of first

% back to image domain
comb = cell(1,2);
for ii=1:2
    for c = 1:size(C{ii},3)
        comb{ii}(:,:,c) = ifft2( C{ii}(:,:,c) )
    end
    comb{ii} = abs(comb{ii}); % discard imaginary part
end
% dispaly
figure('Name','I should forever be grateful to stack overflow!');
subplot(221);
imshow( im{1} ); title('image1');
subplot(222);
imshow( im{2} ); title('image2');
subplot(223);
imshow( comb{1} ); title('mag of 1 with phase of 2');    
subplot(224);
imshow( comb{2} ); title('mag of 2 with phase of 1');    
Licensed under: CC-BY-SA with attribution
Not affiliated with StackOverflow
scroll top