MATLAB: Why can not read images with structures from the folder with different resolution ?

structures

I am reading some images from my folder. I am using structures but If I read from my folder first image all is ok and the FOR statement is ended due to is error message matlab shows:

??? Index exceeds matrix dimensions.
Error in ==> select_part_img at 26
    images_part=images_set(1,i); img=imread(images_part.name);

What is problem ? How can I solve this problem ? In my folder are images with different resolution.

Best Answer

Your line

[img_num,no_used]=size(images_set);

is probably incorrect. images_set will be a structure array vector: one of its two dimensions is going to be 1, probably its second dimension, leading to no_used being 1

When "i" is 2, your line

images_part=images_set(1,i);

is going to be incorrect: it is the first dimension that increases. You need

images_part=images_set(i,1);

Better yet, ignore rows vs columns by using

img_num = length(images_set);

and

images_part=images_set(i);

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imcrop should have a rectangle as input, but you have a mask. You could use

roi = drawrectangle();

instead of imfreehand and then change imcrop to

I = imcrop(I,roi.Position);

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You can try using connected components. With relatively simple problems this could work:

img_original = imread('image.jpeg'); % load image
img_pad = padarray(img_original,[10 10], 0); % pad to simplify cc
threshold = 35;
img_pad(img_pad<threshold) = 0; % threshold image
img_pad(img_pad>=threshold) = 1;
img_inverted = 1-img_pad; % invert image
CC = bwconncomp(img_inverted,4); % find connected components
pixelList = []; % list of pixel in background
for i = 1:length(CC.PixelIdxList)
     % discard small components that are part of the chromosome
    if length(CC.PixelIdxList{1,i}) > 1000 
       pixelList = [pixelList cell2mat(CC.PixelIdxList(i))'] ;
    end
end
mask = zeros(size(img_pad)); % create a mask
mask(pixelList) = 1;
mask = mask(11:end-10,11:end-10); % remove padding
img_corrected = img_original;
img_corrected(logical(mask)) = 255; % set background pixels to white
% PLOT
figure;
subplot(1,4,1); imagesc(img_original); axis image; colormap gray
subplot(1,4,2); imagesc(img_inverted); axis image; colormap gray
subplot(1,4,3); imagesc(mask); axis image; colormap gray
subplot(1,4,4); imagesc(img_corrected); axis image; colormap gray

Best Answer

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