I have a question in image processing, this code shows how to add noise to the image and then retrieve it again ... The problem when retrieving the image error occurs and show the image that was retrieved in white
1 view (last 30 days)
Show older comments
Ahmed Grera
on 2 Sep 2017
Commented: Image Analyst
on 3 Sep 2017
img = imread( ('eight.tif') ); % read image, use gray-level images here.
A = imnoise(img,'Gaussian',0,1);
IMG = fft2( img ); % Fourier of img
sz = size( img );
G = fspecial('gaussian' ,[5,5]); % create a filter with std sigma same size as img
%# Filter it
h = imfilter(A,G,'same');
H = fft2( h ); % Fourier of filter
F = IMG.*H; % filter in Fourier space
f = ifft2( F ); % back to spatial domain.
figure, imagesc(f);title('Gaussian filter in Frequency Domain')
figure,imshow(img),title('Original Image');
figure,imshow(A),title('Noisy Image');
imshow(f)
% Calculate MSE, mean square error.
img =im2double(img);
f =im2double(f);
[M N] = size(img);
error0 = img - f;
Mean_Square_Error = sum(sum(error0 .* error0)) / (M * N)
0 Comments
Accepted Answer
Walter Roberson
on 2 Sep 2017
The result of
img = imread( ('eight.tif') ); % read image, use gray-level images here.
is almost certainly going to be one of the integer data types.
The result of
f = ifft2( F ); % back to spatial domain.
is going to be double precision.
>> min(f(:)),max(f(:))
ans =
2241610061
ans =
2319637632
... that is not even in the same range.
0 Comments
More Answers (1)
Image Analyst
on 3 Sep 2017
Try this, using [] to scale the image before display:
imshow(f, []);
2 Comments
See Also
Categories
Find more on Image Processing Toolbox in Help Center and File Exchange
Products
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!