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graphics - Branching points detection in processed image



I want to get the branching coordinates from a computer-generated image like this one:


Generated tree


After SkeletonTransform and Pruning, I get:


Skeletonized


I would like to develop an algorithm that automatically detect and give coordinates of branching points (I could do it manually but really time consuming).


Thanks!


Edit: I already tried MorphologicalBranchPoints with poor results...



Answer



Use MorphologicalBranchPoints.


im = Binarize@Import["https://i.stack.imgur.com/O0AMj.png"]


skel = Pruning[Thinning[im], 20];

HighlightImage[skel, MorphologicalBranchPoints[skel]]

enter image description here


Another possibility is to use


skel1 = Pruning[Thinning[im, Method -> "MedialAxis"], 10];

as a start then smoothen the result using



skel2 = Thinning@Dilation[skel1, 5]

so that MorphologicalBranchPoints would not give false results.


HighlightImage[skel2, MorphologicalBranchPoints[skel2]]

enter image description here


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