Herror ::dilation2 (
    Hobject Region,
    Hobject StructElement,
    Hobject *RegionDilation,
    const HTuple &Row,
    const HTuple &Column,
    const HTuple &Iterations
)
HRegion HRegion::Dilation2 (
    const HRegion &StructElement,
    const HTuple &Row,
    const HTuple &Column,
    const HTuple &Iterations
) const
HRegionArray HRegionArray::Dilation2 (
    const HRegion &StructElement,
    const HTuple &Row,
    const HTuple &Column,
    const HTuple &Iterations
) const

Dilate a region (using a reference point).

::dilation2 dilates the input regions with a structuring element (StructElement) having the reference point (Row,Column). ::dilation2 has a similar effect as ::dilation1, the difference is that the reference point of the structuring element can be chosen arbitrarily. The parameter Iterations determines the number of iterations which are to be performed with the structuring element. The result of iteration n-1 is used as input for iteration n.

An empty region is generated in case of an empty structuring element.

Structuring elements (StructElement) can be generated with operators such as ::gen_circle, ::gen_rectangle1, ::gen_rectangle2, ::gen_ellipse, ::draw_region, ::gen_region_polygon, ::gen_region_points, etc.


Attention

A dilation always results in enlarged regions. Closely spaced regions which may touch or overlap as a result of the dilation are still treated as two separate regions. If the desired behavior is to merge them into one region, the operator ::union1 has to be called first.


Parameters

Region (input_object)
region(-array) -> Hobject: HRegion(Array)
Regions to be dilated.

StructElement (input_object)
region -> Hobject: HRegion
Structuring element.

RegionDilation (output_object)
region(-array) -> Hobject * : HRegion(Array)
Dilated regions.

Row (input_control)
point.y -> HTuple.long
Row coordinate of the reference point.
Default value: 0

Column (input_control)
point.x -> HTuple.long
Column coordinate of the reference point.
Default value: 0

Iterations (input_control)
integer -> HTuple.long
Number of iterations.
Default value: 1
Suggested values: 1, 2, 3, 4, 5, 7, 11, 17, 25, 32, 64, 128
Typical range of values: 1 <= Iterations
Minimum increment: 1
Recommended increment: 1


Complexity

Let F1 be the area of the input region, and F2 be the area of the structuring element. Then the runtime complexity for one region is:

    O(sqrt(F1) * sqrt(F2) * Iterations) .


Result

::dilation2 returns H_MSG_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_ndim_norm, ::gen_circle, ::gen_ellipse, ::gen_rectangle1, ::gen_rectangle2, ::draw_region, ::gen_region_points, ::gen_struct_elements, ::gen_region_polygon_filled


Possible Successors

::reduce_domain, ::add_channels, ::select_shape, ::area_center, ::connection


Alternatives

::minkowski_add1, ::minkowski_add2, ::dilation1, ::dilation_golay, ::dilation_seq


See also

::erosion1, ::erosion2, ::opening, ::closing


Module

Morphology



Copyright © 1996-2002 MVTec Software GmbH