Here is example of matlab for describing hessian matrix to track vessel. But I can not know about threshold.
I = imread ('D:\program matlab\im0324.bmp');
I = im2double(I);
J = rgb2gray (I);
imwrite (J,'J.bmp');
[x y]=size(J)
h = fspecial('gaussian',[3 3], 0.55) %gaussian function
[px,py] = gradient(h, 0.2, 0.2) % derivative of gaussian
n = [px,py];
b = conv2 (J,n); %convolution
g = hess (h) % hessian matrix
z = eig (g) % eigenvalue (used to threshold)
hhj
K = medfilt2(

; %median filter
d = ordfilt2(K,9,[1 1 1; 1 1 1; 1 1 1]) %dilasion
figure(1), imshow (J)
figure(2), imshow (

figure(3), imshow (K)
figure(4), imshow (d)
I dont know what I write above that's true.
I need yourexplanation.
But I had been suggested by scientiest
Mr. Sofkato read paper:
@InProceedings{frangi:miccai98,
author = {A. Frangi and W. J. Niessen and K. L. Vincken and
M. A. Viergever},
title = {Multiscale Vessel Enhancement Filtering},
booktitle = {Medical Image Computing and Computer Assisted Intervention
1998},
pages = {130--137}
But I am still confused.
Please, help me...
thx