A Framework of Vertebra Segmentation Using the Active Shape Model-Based Approach

Algorithm 3

ASM segmentation procedure.

Input:

  (i)  𝑋: the current shape

  (ii) 𝑋: the mean shape

Result:

  (i)  𝑋^⋆: the final shape

begin

   foreach landmarks in 𝑋  do

   Compute 𝑔;

  𝑋=𝑋;

  repeat

     foreach landmarks in X do

     foreach points along the normal do

      Compute 𝑔;

      Compute 𝐷=(𝑔−𝑔)^𝑇𝑆^𝑔−1(𝑔−𝑔)

     Find 𝑔 minimizing 𝐷;

    Update the landmarks position with the new profile;

    Determine 𝑋 best suited to these landmarks;

  until  Convergence;

  𝑋^⋆=𝑋;