how to connect lines instead of discountinuity

clc; % Clear the command window.

close all; % Close all figures (except those of imtool.)

clear; % Erase all existing variables. Or clearvars if you want.

workspace; % Make sure the workspace panel is showing.

format long g;

format compact;

fontSize = 10;

% Read in image and convert to gray scale.

rgbImage = imread('7002-9.jpg');

I = rgb2gray(rgbImage);

subplot(2,2,1);

imshow(I);

title('7001-21');

% Take histogram.

subplot(2,2,2);

histogram(I);

grid on; %to make grid line

title('histogram Gray image');

% Binarize image.

threshold = 145;

xline(threshold, 'Color', 'r', 'LineWidth',2)

mask=I < threshold;

mask = imfill(mask, 'holes');

% Filter image.

se=strel('sphere',1);

filteredImage = imopen(mask, se);

subplot(2, 2, 3);

imshow(filteredImage);

title('Opened Image');

%%% Measure the areas to determin minAcceptableArea show the histogram of

%%% area

% props = regionprops(filteredImage, 'Area');

% allAreas = sort([props.Area], 'descend');

% histogram(allAreas)

%%Look at the histogram. What area do you think is the minimum size to be a valid crack?

minAcceptableArea = 20;

mask = bwareafilt(filteredImage, [minAcceptableArea, inf]);

subplot(2, 2, 4);

imshow(mask);

%

% % Measure size of crack.

props = regionprops(mask, 'Area');

allAreas = [props.Area];

out=bwferet(mask)

% Measure the areas to know the area not to be considered

% props = regionprops(mask, 'Area');

% allAreas = sort([props.Area], 'descend')

% Get width = area / maximum length

averageWidths = sort(allAreas ./ out.MaxDiameter, 'descend');

message = sprintf('The average width = %.2f pixels.', averageWidths(1));

fprintf('%s\n', message);

caption = sprintf('Binary Image of Cracks larger than %d\nAverage width of largest = %.2f pixels', minAcceptableArea, averageWidths(1));

title(caption, 'FontSize', fontSize, 'Interpreter', 'None');

uiwait(helpdlg(message));

I got the answer of crack width as shown in attachement, my question is as you see after filteration there are discontinousie lines of cracks ,how can I connect between them to be continouse?

Answer 1

[Sarvesh Kale]

Hi yasmin ismail,

You can try to open the image using a different structural element and see if that works, maybe try

SE = strel("line",10,100)

More information can be found at https://in.mathworks.com/help/images/ref/strel.html

Thank you