Skeleton by Thinning Operator

Building the Cantata Workspace


To build a workspace to experiment with the Skeleton by Thinning operator:
  1. Select and Display the image $MMACH/viff/skel.xv using the operators User Defined and Display Image.

  2. Build the two Structuring Elements A and B using two 3x3 Str.El. operators to specify the pattern used in the thinning.

  3. Use operator Skel by Thin specifying the rotation step option: 1 is 45, 2 is 90 and 4 is 180.

Exercises

  1. Are the four skeletons used homotopic?

  2. Change the step of rotation used in the skeletons and see the results?

  3. Use a pattern for detecting a 4-connected interior pixel. What result can you get? Is it homotopic?

  4. Use skel by thinning operator in order to build an homotopic skeleton, then using this same operator, but with other parameters, eliminate the non closed branches of the skeleton.

  5. Repeat the same exercice, but now just to reduce the size of the non closed branches of the skeleton. In the reduction of the size of the skeleton use the N-Thinning operator.