search

timjerman / JermanEnhancementFilter

Jerman's tubular (vessel) and spherical (blob) enhancement filters
Other
61 stars 23 forks source link

Eigen value question. #8

Open BWWwustl opened 2 months ago

BWWwustl commented 2 months ago

Hi. Thanks for sharing the code. It is amazing algorithm.

I am a little bit confused about why the tube-like or elongated structures will have two Higher eigenvalues and one eigenvalue nearly equal to zero? Which exactly these eigenvalues represent for? Thanks!

timjerman commented 2 months ago

Hi, the eigenvalues of the Hessian matrix at a voxel in an image describe the local geometric shape:

image

A tube is elongated in one direction while not in the other two. This can be similarly described using the eigenvalues, where one has low values, while the other two have higher values.

For a detailed explanation please look into the journal and conference papers mentioned in the code description (readme) text.