I want to detect filopodia (red arrow indicates filopodia in a vessel image).
My strategy is that if $I$ is the original and $J$ is the another image after opening operation. Then, $I-J$ is the filopodia. (See Figure 6 in this paper).
To do this, I want to enhance the very thin lines. How to do it? I also have information of front line like this:
Or, do you have any idea for detecting filopodia?