closing_circle ( Region : RegionClosing : Radius : )

Close a region with a circular structuring element.

closing_circle behaves analogously to closing, i.e., the regions' boundaries are smoothed and holes within a region which are smaller than the circular structuring element of radius Radius are closed. The closing_circle operation is defined as a dilation followed by a Minkowski subtraction, both with the same circular structuring element.


Attention

closing_circle is applied to each input region separately. If gaps between different regions are to be closed, union1 or union2 has to be called first.


Parameters

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

RegionClosing (output_object)
region(-array) -> object
Closed regions.

Radius (input_control)
real -> real / integer
Radius of the circular structuring element.
Default value: 3.5
Suggested values: 1.5, 2.5, 3.5, 4.5, 5.5, 7.5, 9.5, 12.5, 15.5, 19.5, 25.5, 33.5, 45.5, 60.5, 110.5
Range of values: 0.5 <= Radius <= 511.5 (lin)
Minimum increment: 1.0
Recommended increment: 1.0


Example
my_closing_circle(ObjType In, double Radius, ObjType *Out)
{
  ObjType  tmp, StructElement;
  circle(StructElement,100.0,100.0,Radius);
  dilation1(In,StructElement,&tmp,1);
  minkowski_sub1(tmp,StructElement,Out,1);
  clear(tmp); clear(StructElement);
}

Complexity

Let F1 be the area of the input region. Then the runtime complexity for one region is:

    O(4 * sqrt(F1) * Radius) .


Result

closing_circle 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

reduce_domain, select_shape, area_center, connection


Alternatives

count, fill_up, closing, closing_circle, closing_golay


See also

dilation1, minkowski_sub1, erosion1, opening



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