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필터 지우기

Exact Image extraction is not possible

조회 수: 2 (최근 30일)
Jhilam Mukherjee
Jhilam Mukherjee 2013년 12월 6일
답변: Image Analyst 2013년 12월 8일
I want to extract the inner black portion of image CT14.jpg using mask.png as a mask by multiplying these two image but every time I get the outer portion of the image. How it is possible to segment these two inner lung portion. please help me.

채택된 답변

Image Analyst
Image Analyst 2013년 12월 8일
Try this:
clc; % Clear the command window.
close all; % Close all figures (except those of imtool.)
imtool close all; % Close all imtool figures if you have the Image Processing Toolbox.
clear; % Erase all existing variables. Or clearvars if you want.
workspace; % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 20;
% Check that user has the Image Processing Toolbox installed.
hasIPT = license('test', 'image_toolbox');
if ~hasIPT
% User does not have the toolbox installed.
message = sprintf('Sorry, but you do not seem to have the Image Processing Toolbox.\nDo you want to try to continue anyway?');
reply = questdlg(message, 'Toolbox missing', 'Yes', 'No', 'Yes');
if strcmpi(reply, 'No')
% User said No, so exit.
return;
end
end
% Read in gray scale demo image.
folder = 'C:\Users\jhilam\Documents\Temporary';
baseFileName = 'CT14.jpg';
% Get the full filename, with path prepended.
fullFileName = fullfile(folder, baseFileName);
% Check if file exists.
if ~exist(fullFileName, 'file')
% File doesn't exist -- didn't find it there. Check the search path for it.
fullFileName = baseFileName; % No path this time.
if ~exist(fullFileName, 'file')
% Still didn't find it. Alert user.
errorMessage = sprintf('Error: %s does not exist in the search path folders.', fullFileName);
uiwait(warndlg(errorMessage));
return;
end
end
grayImage = imread(fullFileName);
% Get the dimensions of the image.
% numberOfColorBands should be = 1.
[rows, columns, numberOfColorBands] = size(grayImage);
if numberOfColorBands > 1
% It's not really gray scale like we expected - it's color.
% Convert it to gray scale by taking only the green channel.
grayImage = grayImage(:, :, 2); % Take green channel.
end
% Display the original gray scale image.
subplot(2, 3, 1);
imshow(grayImage, []);
title('Original Grayscale Image', 'FontSize', fontSize);
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Give a name to the title bar.
set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off')
% Blacken the white bar artifact in the left 5 columns.
grayImage(:, 1:5) = 0;
% Let's compute and display the histogram.
[pixelCount, grayLevels] = imhist(grayImage);
subplot(2, 3, 2);
bar(grayLevels, pixelCount);
grid on;
title('Histogram of original image', 'FontSize', fontSize);
xlim([0 grayLevels(end)]); % Scale x axis manually.
% Binarize the image to get the body.
binaryImage = grayImage > 150;
% Display the binary image.
subplot(2, 3, 3);
imshow(binaryImage, []);
title('Binary Image', 'FontSize', fontSize);
% Fill and get rid of small objects
binaryImage2 = imfill(binaryImage, 'holes');
minAcceptableSize = round(rows*columns*0.05);
binaryImage2 = bwareaopen(binaryImage2, minAcceptableSize);
% Display the binary image.
subplot(2, 3, 4);
imshow(binaryImage2, []);
title('Binary Image 2', 'FontSize', fontSize);
% Invert and OR
binaryImage2 = ~(~binaryImage2 | binaryImage);
% Display the binary image.
subplot(2, 3, 5);
imshow(binaryImage2, []);
axis on;
title('Binary Image 2', 'FontSize', fontSize);
% Fill again
binaryImage3 = imfill(binaryImage2, 'holes');
% Get rid of small things again.
binaryImage3 = bwareaopen(binaryImage3, minAcceptableSize);
% And it with binary image 2
binaryImage3 = binaryImage3 & binaryImage2;
% Display the binary image.
subplot(2, 3, 6);
imshow(binaryImage3, []);
title('Binary Image 3', 'FontSize', fontSize);
uiwait(helpdlg('Done with Demo by Image Analyst!'));

추가 답변 (2개)

Image Analyst
Image Analyst 2013년 12월 6일
How did you get that mask? Why not get one that is not connected to the outer black stuff? Anyway to mask the gray image by a binary (logical) image, you can do it in two ways.
maskedImage = grayImage; % Initialize
maskedImage(~mask) = 0;
or
maskedImage = grayImage .* uint8(mask); % or uint16, whatever grayImage is.
  댓글 수: 1
Image Analyst
Image Analyst 2013년 12월 8일
That's because the Otsu method is lousy. It rarely picks good thresholds for real world images unless they're very contrasty with a bimodal histogram.

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Jhilam Mukherjee
Jhilam Mukherjee 2013년 12월 8일
At first the Otsu's thresholding technique is applied on the second image, which give a binary thresholded image, then an= morphological operation performed over thresholded image that yielded the first image.
I get output the above image but my desired out put is
in gray scale format. but I can't obtained this output. In each images I found the above image. How is it possible

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