Could someone help with how to use the frangi filter to segment the venous structure? I do not quite understand the min and max values for the threshold.
Welcome to the forum!
Those parameters are not thresholds, they are scales. You should give large values of those parameters if you expect the “tubes” in your image are big/wide, and small values if you expect them to be small/thin. Details here.
Hope that helps,
Hi John (@bogovicj),
Thanks for your reply. I do not get the desired results regardless which number I tried. Could it be due to the fact the images I used are SWI images with the venous structure showing in dark instead of bright?
Hi Wei @wei_liu,
Yes, this could be the issue - have you tried inverting your images (
Edit > Invert ) before applying the Frangi filter?
If you are still getting unexpected results, perhaps consider posting your original and post-processed images to this forum post - that could be helpful for others to give you ideas.
This does the trick. Thank you!