Determining area of irregular shape

Hi! Can you help me how to determine area in this picture, without borders? In ImageJ or somewhere else? o10.2

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Hi,

I am not entirely sure what you mean with “without borders”. I assume you want to measure the area enclosed by the black lines.

You can measure the area by using the Wand-Selection-Tool. It probably works even better when smoothing (median-filter, middle) and detecting edges (right) first.
grafik

this code replicates what I did and measures the area.

run("Duplicate...", " ");
run("Median...", "radius=1");
run("Find Edges");
doWand(45, 53, 10.0, "4-connected");
run("Measure");

Does this help?

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Joachim,

Thanks a lot. I have just one more question, since depending on crop or whatever I get different results, can you give me a hint how to properly deal with this issue or at least avoid it. Since I’m not sure why this happens. Here are the examples

22.0.png

22.1.png

ned, 25. okt 2020. 10:28 Joachim via Image.sc Forum <imagej@discoursemail.com> је написао/ла:

Hey,

somehow the examples are not displayed for me, can you try uploading them again?

22.0

Or this situation:

Hey,

from your screenshots it looks like you could get better results either by increasing the median-filter radius (to smooth out some of the noise you still have) or by increasing the tolerance of the wand-tool (double-click on the symbol). The exact values would have to be determined by trial.

But it is rather difficult to say something precise without one of the original images to try things, so if you still encounter problems after changing these settings, it would help us if you could post one of the images in the original quality.

I’ve solved the problem! Thanks a lot for your help!

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