Measure the length of the Crack?

I have processed a image using edge detection operator and now i have to find the Length of the Crack i.e the length of the white part,If someone could help me figure out how to do it?

Answer 1

[Walter Roberson]

I suggest that you bwmorph 'close' then bwmorph 'skel' then bwmorph 'spur'. Then regionprops 'perimeter', probably divided by 2.

Instead of bwmorph 'close' you can imclose()

[Image Analyst]

After bwmorph(skeleton, 'spur') you might be able to just filter and sum the image to get the length of the skeleton in pixels

binaryImage = bwareafilt(binaryImage, 1); % Take largest blob only.
lengthOfSkel = sum(binaryImage(:));

[Walter Roberson]

One question is whether you want euclidean distance between the endpoints of the crack, or if you want the distance you get by following the crack. The suggestions we have given above are for distance following the crack.

[Walter Roberson]

Fairuz Husna comments (to me)

I have the same problem

[Walter Roberson]

Fairuz Husna, you have not been clear as to which problem you have.

[Pranit Patil]

How do we calculate the width of the crack and the direction in which it propagates?