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lowlandsLowlandsLowlandslowlandslowlands🔗

Short description🔗

lowlandsLowlandsLowlandslowlandslowlands — Detect all gray value lowlands.

Signature🔗

lowlands( image Image, out region Lowlands )void Lowlands( const HObject& Image, HObject* Lowlands )static void HOperatorSet.Lowlands( HObject image, out HObject lowlands )def lowlands( image: HObject ) -> HObject

Herror lowlands( const Hobject Image, Hobject* Lowlands )

Herror T_lowlands( const Hobject Image, Hobject* Lowlands )

HRegion HImage::Lowlands( ) const

HRegion HImage.Lowlands( )

Description🔗

lowlandsLowlands extracts all points from Imageimageimage with a gray value less or equal to the gray value of its neighbors (8-neighborhood) and returns them in Lowlandslowlandslowlands. Each lowland is returned as a separate region.

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🔗

Imageimageimage (input_object) singlechannelimage(-array) → object (byte / direction / cyclic / int1 / int2 / uint2 / int4 / int8 / real)HObject (byte / direction / cyclic / int1 / int2 / uint2 / int4 / int8 / real)HImage (byte / direction / cyclic / int1 / int2 / uint2 / int4 / int8 / real)HObject (byte / direction / cyclic / int1 / int2 / uint2 / int4 / int8 / real)Hobject (byte / direction / cyclic / int1 / int2 / uint2 / int4 / int8 / real)

Image to be processed.

Lowlandslowlandslowlands (output_object) region-array → objectHObjectHRegionHObjectHobject *

Extracted lowlands as regions (one region for each lowland).

Example🔗

(C)

read_image(&Image,"fabrik")\;
corner_responce(Image,&CornerResp,5,0.04)\;
lowlands(CornerResp,&Minima)\;
set_colored(WindowHandle,12)\;
disp_region(Minima,WindowHandle)\;
T_area_center(Minima,NULL,&Row,&Col)\;
(C++)
#include "HIOStream.h"
#if !defined(USE_IOSTREAM_H)
using namespace std\;
#endif
#include "HalconCpp.h"
using namespace Halcon\;

int main (int argc, char *argv[])
{
  if (argc != 2)
  {
    cout << "Usage : " << argv[0] << " <name of image>" << endl\;
    return (-1)\;
  }
 HImage   image (argv[1])\;
  HWindow  win\;
 image.Display (win)\;
 HImage       cres = image.CornerResponse (5, 0.04)\;
  HRegionArray mins = cres.Lowlands ()\;
 win.SetColored (12)\;
  mins.Display (win)\;
  win.Click ()\;
 return (0)\;
}

Combinations with other operators🔗

Combinations

Possible predecessors

binomial_filterBinomialFilter, gauss_filterGaussFilter, smooth_imageSmoothImage

Possible successors

area_centerAreaCenter, get_region_pointsGetRegionPoints, select_shapeSelectShape

Alternatives

lowlands_centerLowlandsCenter, gray_skeletonGraySkeleton, local_minLocalMin

See also

monotonyMonotony, topographic_sketchTopographicSketch, corner_responseCornerResponse, texture_lawsTextureLaws

Module🔗

Foundation