How to know the crack area on the segmented 3d image?

Hi,

I have some segmented 3d images for certain particles.

Here is one example,

You can find some holes on the surface (circled in red) that make the hollow region inside particle connect to the outside. I am struggled to find the surface area of those holes. I have tried to use ’imclose’ to fill the hollow region and subtract to its original one and get hollow region structure. But it is not helpful for finding just the surface area of circled region.

Could anyone have some ideas？Thanks!

Answer 1

[Image Analyst]

That is not a segmented image, at least it's not segmented for the things you care about - which are the cracks. I don't even know what you want. There are tons of little indentations and concavities all over that shape. Somehow you need to isolate just the ones you are interested in. The method you suggested should work reasonably well if you choose the right structuring element. If it doesn't, you might have to somehow manually hand-trace the regions.

[Dongyu Liang]

Hi,

This is what I got after 'activecontour' operation from CT images based on masks and showing in ‘volumeViewer‘. This particle structure is what I want. But I also want to know external surface area and the cracks surface area, so I can know how many persent area is crack on entire external surface. By using 'imclose', 'imfill', 'imsubtract', I can get hollow region structure which is solid. This structure surface area conatins the cracks area with the internal surface area of original structure together. I still do not know how to separate them. For some particles, there are too many cracks on it and I am not sure they can be easily hand-traced.

Please let me know if I am not clear or you have any other ideas. Thanks!