[Insight-users] how to calculate point using eigen vector

[Arunachalam Kana]

Hi itk users,

 

I am trying to write an algorithm to trace centre line of a tube shape
in 3D CT image.

 

I am using the hessian matrix to get the direction of the tube shape.

 

The Eigen values and vector of hessian matrix for coordinate [9,5,2]:

 

Eigen value: -560.862  -1022.66  12.2557 (not in any order)

 

Eigen vectors:   0.701     0.708      0.078

                                -0.702   0.705     -0.092

                               -0.120   0.010     0.992

 

When arranged in |Lambda1| < |Lambda2| < |Lambda3| , i get 12.2557 as
Lambda1.

If my understanding of literature is right, then the direction of the
tube centre line will

point in the direction of eigenvector corresponding to 12.2557 which is
0.992.

 

If i am right so far, then my question is :

1.       how to calculate the next coordinate to which i have to move
from [9,5,2]?

2.       Is there any literature to refer to ?

 

Help to solve this problem will be highly appreciated.

 

Thank you,

Regards,

Kana

 

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