dilation_rectangle1DilationRectangle1DilationRectangle1dilation_rectangle1dilation_rectangle1🔗

Short description🔗

dilation_rectangle1DilationRectangle1DilationRectangle1dilation_rectangle1dilation_rectangle1 — Dilate a region with a rectangular structuring element.

Signature🔗

dilation_rectangle1( region Region, out region RegionDilation, extent.x Width, extent.y Height )

Description🔗

dilation_rectangle1DilationRectangle1 applies a dilation with a rectangular structuring element to the input regions Regionregionregion. The size of the structuring rectangle is Widthwidthwidth x Heightheightheight. The operator results in enlarged regions, and the holes smaller than the rectangular mask in the interior of the regions are closed.

dilation_rectangle1DilationRectangle1 is a very fast operation because the height of the rectangle enters only logarithmically into the runtime complexity, while the width does not enter at all. This leads to excellent runtime efficiency, even in the case of very large rectangles (edge length \(>\) 100).

Attention🔗

dilation_rectangle1DilationRectangle1 is applied to each input region separately. If gaps between different regions are to be closed, union1Union1 or union2Union2 has to be called first.

To enlarge a region by the same amount in all directions, Widthwidthwidth and Heightheightheight must be odd. If this is not the case, the region is dilated by a larger amount at the right or at the bottom, respectively, than at the left or at the top.

Execution information🔗

Execution information

Multithreading type: reentrant (runs in parallel with non-exclusive operators).
Multithreading scope: global (may be called from any thread).
Automatically parallelized on tuple level.

Parameters🔗

Regionregionregion (input_object) region(-array) → objectHObjectHRegionHObjectHobject

Regions to be dilated.

RegionDilationregionDilationregion_dilation (output_object) region(-array) → objectHObjectHRegionHObjectHobject *

Dilated regions.

Widthwidthwidth (input_control) extent.x → (integer)HTuple (Hlong)HTuple (int / long)intHtuple (Hlong)

Width of the structuring rectangle.

Default: 1111
Suggested values: 1, 2, 3, 4, 5, 11, 15, 21, 31, 51, 71, 101, 151, 201
Value range: 1 ≤ Width ≤ 511 (lin)
Minimum increment: 1
Recommended increment: 10

Heightheightheight (input_control) extent.y → (integer)HTuple (Hlong)HTuple (int / long)intHtuple (Hlong)

Height of the structuring rectangle.

Default: 1111
Suggested values: 1, 2, 3, 4, 5, 11, 15, 21, 31, 51, 71, 101, 151, 201
Value range: 1 ≤ Height ≤ 511 (lin)
Minimum increment: 1
Recommended increment: 10

Example🔗

(C)

threshold(Image,&Light,220.0,255.0)\;
dilation_rectangle1(Light,&Wide,50,50)\;
set_color(WindowHandle,"red")\;
disp_region(Wide,WindowHandle)\;
set_color(WindowHandle,"white")\;
disp_region(Light,WindowHandle)\;

(C++)

#include "HIOStream.h"
#if !defined(USE_IOSTREAM_H)
using namespace std\;
#endif
#include "HalconCpp.h"

main()
{
  cout << "Reproduction of 'dilation_rectangle ()'" << endl\;
  cout << "First = original image " << endl\;
  cout << "Blue  = after dilation " << endl\;
  cout << "Red   = after segmentation " << endl\;
 HByteImage img("monkey")\;
  HWindow    w\;
 HRegionArray regs   = (img >= 220).Connection()\;
  HRegionArray dilreg = regs.DilationRectangle1 (2, 4)\;
                       img.Display (w)\;      w.Click ()\;
  w.SetColor ("blue")\;  dilreg.Display (w)\;   w.Click ()\;
  w.SetColor ("red")\;   regs.Display (w)\;     w.Click ()\;
 return(0)\;
}

Complexity🔗

Let \(F1\) be the area of an input region and \(H\) be the height of the rectangle. Then the runtime complexity for one region is:

\[\begin{eqnarray*} O(\sqrt{F1} \cdot ld(H)) \enspace . \end{eqnarray*}\]

Result🔗

dilation_rectangle1DilationRectangle1 returns 2 (H_MSG_TRUE) if all parameters are correct. The behavior in case of empty or no input region can be set via:

no region: set_system('no_object_result',<RegionResult>)
empty region: set_system('empty_region_result',<RegionResult>)

Otherwise, an exception is raised.

Combinations with other operators🔗

Combinations

Possible predecessors

thresholdThreshold, regiongrowingRegiongrowing, connectionConnection, union1Union1, watershedsWatersheds, class_ndim_normClassNdimNorm

Possible successors

reduce_domainReduceDomain, select_shapeSelectShape, area_centerAreaCenter, connectionConnection

Alternatives

minkowski_add1MinkowskiAdd1, minkowski_add2MinkowskiAdd2, expand_regionExpandRegion, dilation1Dilation1, dilation2Dilation2, dilation_circleDilationCircle

Module🔗

Foundation