I wish to read 322 images of mammogram then wish to apply the enhancement techniques say histogram equalization and then wish to calculate contrast improvement index (CII) of all 322 images followed by showing results of all 322 images graphically

My problem is I am not able to understand how to use for loop or other technique to read 322 images followed by applying the enhancement techniques on all 322 images, calculation of CII and entropy of all and showing their results graphically. I have all 322 images in a folder.

Answer 1

[Image Analyst]

See the FAQ: https://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F

Answer 2

[awezmm]

First check out these, I think they are doing exactly what you want: mmgimg1

mmgimg2

Make sure your images are grayscale

For reading images I suggest you use imagedatastore: imageDatastore

You would do:

%Put the full path of the folder containing all your images in location argument below.
imds = imageDatastore('location')

%Now you will have to use for loop to read all the images
for i = 1:length(imds.Files)

       %getting file name of an image
       curr_image_cell_name = imds.Files(i);
       curr_image_file_name = curr_image_cell_name{1,1};

       %reading current image
       curr_image = imread(curr_image_file_name);

       %now you can adjust your image here, note that your images have to be grayscale
       %there are a variet methods: check out this site: 
       %https://www.mathworks.com/help/images/contrast-enhancement-techniques.html 

      %some examples, note that your images have to be grayscale
      image_imadjust = imadjust(curr_image);
      image_histeq = histeq(curr_image);
      image_adapthisteq = adapthisteq(curr_image);

      %you can show this graphically by plotting the histograms of different images 
      %figure. This is explained in: 
      %https://www.mathworks.com/help/images/contrast-enhancement-techniques.html 
      imshow(imhist(curr_image))

      %entropy of grayscale image: 
      %https://www.mathworks.com/help/images/ref/entropy.html 
      ent = entropy(curr_image);
      disp(ent)
end

[jyoti dabass]

Thanks for the code. It gives entropy values for all 322 images. But i also wish to know how to plot the results graphically. like on x images we have 1 to 322, on y axis we must have value of entropy corresponding to image.

[awezmm]

cant you accept my answer since i gave the code and you can use plot for that: https://www.mathworks.com/help/matlab/ref/plot.html

[jyoti dabass]

I accepted the answer but i had tried plot. Its not giving the waveforms required. Anyways thanks for the code.

[Image Analyst]

For the end of the loop, try

      ent(i) = entropy(curr_image);
      fprintf('For image #%d of %d, the entropy is  %f.\n', i, length(imds.Files), ent(i));
end
plot(ent, 'b-', 'LineWidth', 2);
grid on;

Answer 3

[jyoti dabass]

Thank you..Its working fine.