morph_skiz ( Region : RegionSkiz : Iterations1, Iterations2 : )

Thinning of a region.

morph_skiz first performs a sequential thinning (thinning_seq) of the input region with the element 'l' of the Golay alphabet. The number of iterations is determined by the parameter Iterations1. Then a sequential thinning of the resulting region with the element 'e' of the Golay alphabet is carried out. The number of iterations for this step is determined by the parameter Iterations2. The skiz operation serves to compute a kind of skeleton of the input regions, and to prune the branches of the resulting skeleton. If the skiz operation is applied to the complement of the region, the region and the resulting skeleton are separated.

If very large values or 'maximal' are passed for Iterations1 or Iterations2, the processing stops if no more changes occur.


Parameters

Region (input_object)
region(-array) -> object
Regions to be thinned.

RegionSkiz (output_object)
region(-array) -> object
Result of the skiz operator.

Iterations1 (input_control)
integer -> integer / string
Number of iterations for the sequential thinning with the element 'l' of the Golay alphabet.
Default value: 100
Suggested values: 'maximal', 0, 1, 2, 3, 5, 7, 10, 15, 20, 30, 40, 50, 70, 100, 150, 200, 300, 400
Range of values: 0 <= Iterations1
Minimum increment: 1
Recommended increment: 1

Iterations2 (input_control)
integer -> integer / string
Number of iterations for the sequential thinning with the element 'e' of the Golay alphabet.
Default value: 1
Suggested values: 'maximal', 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 17, 20, 30, 40, 50
Range of values: 0 <= Iterations2
Minimum increment: 1
Recommended increment: 1


Complexity

Let F be the area of the input region. Then the runtime complexity for one region is

      O((Iterations1 + Iterations2) * 3 * sqrt(F)) .


Result

morph_skiz returns TRUE if all parameters are correct. The behavior in case of empty or no input region can be set via:

  a) no region:    set_system(::'no_object_result',<RegionResult>:)
  b) empty region: set_system(::'empty_region_result',<RegionResult>:)
Otherwise, an exception is raised.


Possible Predecessors

threshold__, regiongrowing__, connection, union1, watersheds, class_ndim1__


Possible Successors

pruning, reduce_domain, select_shape, area_center, connection, background_seg, complement__


Alternatives

skeleton, thinning_seq, morph_skeleton, interjacent


See also

thinning, hit_or_miss_seq, difference



Copyright © 1996-1997 MVTec Software GmbH