Posted by
Michael Schmid on
Mar 01, 2017; 7:24pm
URL: http://imagej.273.s1.nabble.com/crack-length-determination-tp5018201p5018217.html
Neel wrote:
> In a 8-bit image, pixel with 255 value (dark) are representing cracks
in concrete. Now as a crack is a linear feature extending over some
length, dark pixels are forming a linear shape. Does anybody know how to
trim the corner pixels in such linear arrangement so that I can get to
the middle pixel?
Hi Neel,
you can use Process>Find Maxima with 'light background'. For contiguous
areas with a constant pixel value, it gives you the pixel of this area
(this crack, in your case) that is closest to the center of mass of all
pixels of this crack.
You can select whether you want a point selection, an image with only
the points of relevance or a list with the coordinates in the Results table.
As it seems some cracks are not contiguous in your sample image (but
they probably are in reality), you may need some preprocessing to join
the segments. The easiest would be dilation by Process>Filters>Maximum
followed by Skeletonize.
Michael
________________________________________________________________
On 01/03/2017 19:39, negupta wrote:
> Thanks again for the new probable solution.
>
> I have come up with another possible solution to solve this problem using
> ImageJ. But I have one more issue and if I get satisfactory result from it
> may be I can share it for future purpose.
>
> So the situation is like this:
> In a 8-bit image, pixel with 255 value (dark) are representing cracks in
> concrete. Now as a crack is a linear feature extending over some length,
> dark pixels are forming a linear shape. Does anybody know how to trim the
> corner pixels in such linear arrangement so that I can get to the middle
> pixel? I know I can do it visually but then it would not be accurate enough.
>
> Please ask If you don't understand the fact. I am sharing the image so that
> you can understand more what I am trying to say.
>
> Neel
> <
http://imagej.1557.x6.nabble.com/file/n5018215/Classification_result_skeleton.png>
>
>
>
> --
> View this message in context:
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>
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