Asked by Zara Khan
on 16 Sep 2018 at 14:57

I am working on a dataset which consists of 1000 binary images. Following things are needed to be done for every single images: 1. Make all images to vertically align(if any of them are already vertically align then leave as it is) 2. Draw 8 circles with different radius values 3. Store each circle perimeter pixel to a profile. I have tried doing this. For storing perimeter pixel values I have used poly2mask and have considered its boundary. But this is taking too much of the time. Program is going extremely extremely slow. Unable to get outputs. Only using few data I am able to check. For 1000 data I waited for a whole day still not getting my desired output. Please anyone help me in doing this.

clc; close all; clear; workspace; folder = 'D:\data_set'; filepattern = fullfile(folder, 'P*.png'); directoryInfo = dir(filepattern); numImages = length(directoryInfo); for k = 1 : numImages baseFileName = directoryInfo(k).name; fullFileName = fullfile(folder, baseFileName); a = imread(fullFileName); bwimg =bwareafilt(~a, 1); s=regionprops(bwimg,'Centroid','Orientation','MajorAxisLength','MinorAxisLength'); theta=s.Orientation; if theta>=0 && theta<90 phi=90-theta; y=imrotate(bwimg,phi); else phi=90+theta; y=imrotate(bwimg,-phi); end circleCenterX =s.Centroid(1); circleCenterY =s.Centroid(2); diameters = mean([s.MajorAxisLength s.MinorAxisLength],2); r1 =diameters/2; r2=diameters/3; r3=diameters/4; r4=diameters/5; r5=0.6*diameters; r6=0.7*diameters; r7=0.8*diameters; r8=0.9*diameters; radii(k,:)=[r1, r2, r3, r4,r5, r6, r7, r8]; [m,n]=size(radii); t=0:0.001:2*pi; for i=1:m for j=1:n x = circleCenterX + radii(i,j) * sin(t); y = circleCenterY + radii(i,j) * cos(t); bw = poly2mask(x,y,256,256); end end end end

Answer by Image Analyst
on 16 Sep 2018 at 15:28

Not sure what this code does with making increasingly large circles, but this seems to work:

clc; % Clear the command window. clearvars; close all; % Close all figures (except those of imtool.) workspace; % Make sure the workspace panel is showing. format long g; format compact; fontSize = 20;

clc; close all; clear; workspace; folder = pwd; % 'D:\data_set'; filepattern = fullfile(folder, '*.png'); directoryInfo = dir(filepattern); numImages = length(directoryInfo); t=linspace(0, 2*pi, 720); for k = 1 : numImages baseFileName = directoryInfo(k).name; fullFileName = fullfile(folder, baseFileName) rgbImage = imread(fullFileName); % Get the dimensions of the image. % numberOfColorChannels should be = 1 for a gray scale image, and 3 for an RGB color image. [rows, columns, numberOfColorChannels] = size(rgbImage) if numberOfColorChannels > 1 % It's not really gray scale like we expected - it's color. % Use weighted sum of ALL channels to create a gray scale image. % grayImage = rgb2gray(rgbImage); % ALTERNATE METHOD: Convert it to gray scale by taking only the green channel, % which in a typical snapshot will be the least noisy channel. grayImage = rgbImage(:, :, 1); % Take red channel. else grayImage = rgbImage; % It's already gray scale. end subplot(2, 2, 1); imshow(grayImage); title(baseFileName, 'Interpreter', 'none'); % Enlarge figure to full screen. set(gcf, 'Units', 'Normalized', 'OuterPosition', [0, 0.04, 1, 0.96]); drawnow; % Now it's gray scale with range of 0 to 255. binaryImage =bwareafilt(~grayImage, 1); subplot(2, 2, 2); imshow(binaryImage); title('Binary Image', 'Interpreter', 'none'); drawnow; s=regionprops(binaryImage,'Centroid','Orientation','MajorAxisLength','MinorAxisLength'); if isempty(s) % Skip this image if there are no blobs. continue; end theta=s.Orientation; if theta>=0 && theta<90 phi=90-theta; y=imrotate(binaryImage,phi); else phi=90+theta; y=imrotate(binaryImage,-phi); end circleCenterX =s.Centroid(1); circleCenterY =s.Centroid(2); diameters = mean([s.MajorAxisLength, s.MinorAxisLength],2) r1 =diameters/2; r2=diameters/3; r3=diameters/4; r4=diameters/5; r5=0.6*diameters; r6=0.7*diameters; r7=0.8*diameters; r8=0.9*diameters; radii(k,:)=[r1, r2, r3, r4, r5, r6, r7, r8]; [rowsR, colsR]=size(radii); bw = false(rows, columns); for j=1:colsR thisRadius = radii(1, j); x = circleCenterX + thisRadius * sin(t); y = circleCenterY + thisRadius * cos(t); bw = bw | poly2mask(x, y, rows, columns); subplot(2, 2, 3); imshow(bw); caption = sprintf('Radius = %.3f', thisRadius); title(caption); drawnow; end if k < numImages promptMessage = sprintf('Do you want to Continue processing,\nor Quit processing?'); titleBarCaption = 'Continue?'; buttonText = questdlg(promptMessage, titleBarCaption, 'Continue', 'Quit', 'Continue'); if contains(buttonText, 'Quit') break; end end end msgbox('Done!');

Zara Khan
on 16 Sep 2018 at 16:53

Zara Khan
on 16 Sep 2018 at 18:00

What ia the use of this line bw = bw | poly2mask(x, y, rows, columns); Will you please explain me ??

Image Analyst
on 17 Sep 2018 at 1:54

Sign in to comment.

Opportunities for recent engineering grads.

Apply Today
## 0 Comments

Sign in to comment.