How to remove branches from skeleton image?

I have a root plant in image below.

I have to detect primary root. I got the skeleton of root like image below

How to remove all branches in skeleton image to get primary root?

Please help me!

Thanks!

[adrian satmari]

Hi @Tran Quoc Huy

I got some problem, did you find some solution for this?

Thank you!

[darova]

Look here

Try attached file

Answer 1

[Brenda Silva]

The function bwmorph (see matlab documentation) might help you with this. Try to use im = bwmorph(im,'spur',Inf).