Compute the likeliness of an image region to contain vessels or other image ridges , according to the method described by Frangi et al. :
Frangi, Alejandro F., et al. "Multiscale vessel enhancement filtering." International Conference on Medical Image Computing and Computer-Assisted Intervention. Springer Berlin Heidelberg, 1998.
Code adapted from Matlab to python from : https://www.mathworks.com/matlabcentral/fileexchange/24409-hessian-based-frangi-vesselness-filter