MATLAB: How to find the distance between the outer most points of two objects in a binary image

binaryimage processingMATLAB

Hello everyone,

I have a series of images like the one shown below, which represent cracks in a steel specimen. Through various filters I got a binary image which includes the actual crack or cracks as the white objects. I would like to calculate the distance between the outer most Points (i.e. the crack tips). Because I have a large series of these images (several hundreds with slightly different cracks) I do not want to use imdist or similar manual functions to get the distance out of the image.

Best Answer

I = imread('download.png') ;
[y,x]  =find(I) ;
% GEt bounding box of data 
x0 = min(x) ; x1 = max(x) ; 
y0 = min(y) ; y1 = max(y) ; 
C = [x0 y0 ; x1 y0 ; x1 y1 ; x0 y1 ; x0 y0] ;
imshow(I)
hold on
plot(C(:,1),C(:,2),'r')
height = abs(y0-y1)

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MATLAB: How to use a for loop to find all row ?!

I = imread('crack_crop.jpeg') ;
I = rgb2gray(I) ;
[y,x] = find(I==0) ;
imshow(I)
hold on
plot(x,y,'.r')
%% GEt bounding box
x0 = min(x) ; x1 = max(x) ;
y0 = min(y) ; y1 = max(y) ;
%
B = x1-x0 ;
L = y1-y0 ;
R = [x0 y0 ; x0 y1 ; x1 y1 ; x1 y0] ;
% patch(R(:,1),R(:,2),'b')
if L>B
    title('Vertical Crack')
else
    title('Horizonatal Crack')
end

MATLAB: How to count the white pixels for each column in a binary image

I = imread('download.png') ;
I = rgb2gray(I) ;
idx = I~=0 ;
iwant = sum(idx)

Best Answer

Related Solutions

MATLAB: How to use a for loop to find all row ?!

MATLAB: How to count the white pixels for each column in a binary image

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