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Enhancing Image with Histogram Matching and Median Filter

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I want to enhance the MRI image by histogram matching and median filter, but the result is unexpected with this code:
% Grayscaled Image
A = imread ('D:\TESIS\1.jpg');
B = rgb2gray(A);
% High Pass Filtered Image
h = fspecial('log', [3 3], 0.5);
C = imfilter (B,h);
% Enhanced Image
D = imhistmatch(B,C);
E = medfilt2(D);
figure;
subplot(2,2,1), imshow(A); title('Original Image');
subplot(2,2,2), imshow(B); title('Grayscaled Image');
subplot(2,2,3), imshow(C); title('High Pass Filtered Image');
subplot(2,2,4), imshow(D); title('Enhanced Image');
My image is 1.jpg and I'm expecting the result is similar to this Test.png instead of in the code. I am wondering what is missing. Thank you.

  2 Comments

Image Analyst
Image Analyst on 24 Jan 2020
Why don't you plot all three histograms (before, reference, and after) to see what they look like?
If you want an EXACT histogram match, see My File Exchange for code that does that much more exactly than the built-in function.
Qvna Lhyvnav
Qvna Lhyvnav on 23 Feb 2020
Thank you for the answer before. I already added the grayscale image with the built-in function image and I got the expected result.

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Accepted Answer

KALYAN ACHARJYA
KALYAN ACHARJYA on 24 Jan 2020
Edited: KALYAN ACHARJYA on 24 Jan 2020
I want to enhance the MRI image by histogram matching and median filter
Histogram Matching:
Are you considering with target image?
Median filter:
A median filter use for signal smoothing, it may smooth the internal part, but I don't think it can generate the clear border view.

  1 Comment

Qvna Lhyvnav
Qvna Lhyvnav on 23 Feb 2020
Histogram Matching:
Yes.
Median Filter:
Yes, it is but I used it after added the grayscale image with the histogram matching image and I got the expected result.

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