Trying to find the error in logic

There is some problem in the logic of this code. It is supposed to segment the lungs from chest radiographs for the set threshold but it is not doing that correctly (providing same results for any threshold value).

clear; clc; close all;

%% Loading images

Threshold = 240;

raw_x_ray='ee.png';

I=imread(raw_x_ray);

figure(101);

imshow(I);

colormap(gray);

title('Grayscale X-Ray');

I=wiener2(I, [7 7]);

figure(102);

subplot(2,1,1);

imshow(I);

subplot(2,1,2);

imhist(I, 256);

a_thresh = I >= Threshold; % set this threshold

[labelImage, numberOfBlobs] = bwlabel(a_thresh);

props = regionprops(a_thresh,'all');

sortedSolidity = sort([props.Solidity], 'descend');

SB = sortedSolidity(1);

if SB == 1

binaryImage = imbinarize(I); figure(103);

imshow(binaryImage); colormap(gray);

SE = strel('square',3);

morphologicalGradient = imsubtract(imdilate(binaryImage, SE),imerode(binaryImage, SE));

mask = imbinarize(morphologicalGradient,0.03);

SE = strel('square',2);

mask = imclose(mask, SE);

mask = imfill(mask,'holes');

mask = bwareafilt(mask,2); % control number of area show

notMask = ~mask;

mask = mask | bwpropfilt(notMask,'Area',[-Inf, 5000 - eps(5000)]);

showMaskAsOverlay(0.5,mask,'r'); % you have to download app/function showMaskAsOverlay

BW2 = imfill(binaryImage,'holes');

new_image = BW2 ;

new_image(~mask) = 0; % invert background and holes

B=bwboundaries(new_image); % can only accept 2 dimensions

figure(104);

imshow(new_image);

ss = strcat('Result_',num2str(Threshold),'.mat');

save(ss,'new_image');

hold on

visboundaries(B);

im8 = im2uint8(new_image);

imwrite(im8, 'ccc.png')

end

[John Petersen]

It would help if you could narrow it down a little more and maybe explain what is wrong about it?

[Rida Memon]

The code is providing same output for any threshold value be it 90,110 or 250 etc.. I feel the problem is in these lines: SB = sortedSolidity(1); if SB == 1

Answer 1

[Daniel Vieira]

the Threshold parameter doesn't matter at all in your code. you binarize the image with the threshold, measure solidity of blobs, take the largest solidity, and if it's 1 (which is extremely likely) then you throw the previous binarization away and binarize again with default values of imbinarize. I'm not sure that's what you intended to do, but to me it seems unntentional, I don't think this approach goes anywhere.

[Rida Memon]

Actually i have picked that code from a site. I understand that there is above stated problem with this code. Therefore i need help to correct this code. It should not throw but use that previously obtained threshold. Kindly help me if you can.