erosion_golayerosion_golayerosion_golayErosionGolayErosionGolay (Operator)

Name

erosion_golayerosion_golayerosion_golayErosionGolayErosionGolay — Erode a region with an element from the Golay alphabet.

Signature

Description

erosion_golayerosion_golayerosion_golayErosionGolayErosionGolay erodes a region with the selected element GolayElementGolayElementGolayElementGolayElementgolayElement from the Golay alphabet. The following structuring elements are available:

'l', 'm', 'd', 'c', 'e', 'i', 'f', 'f2', 'h', 'k'.

The rotation number RotationRotationRotationRotationrotation determines which rotation of the element should be used, and whether the foreground (even) or background version (odd) of the selected element should be used. The Golay elements, together with all possible rotations, are described with the operator golay_elementsgolay_elementsgolay_elementsGolayElementsGolayElements. The operator works by shifting the structuring element over the region to be processed (RegionRegionRegionRegionregion). For all positions of the structuring element fully contained in the region, the corresponding reference point (relative to the structuring element) is added to the output region. This means that the intersection of all translations of the structuring element within the region is computed.

The parameter IterationsIterationsIterationsIterationsiterations 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.

Attention

Not all values of RotationRotationRotationRotationrotation are valid for any Golay element. For some of the values of RotationRotationRotationRotationrotation, the resulting regions are identical to the input regions.

Parallelization

• 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

Complexity

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

       O(3 * sqrt(F)) .

Result

erosion_golayerosion_golayerosion_golayErosionGolayErosionGolay 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: empty region: set_system('empty_region_result',<RegionResult>)

Otherwise, an exception is raised.

Possible Predecessors

thresholdthresholdthresholdThresholdThreshold, regiongrowingregiongrowingregiongrowingRegiongrowingRegiongrowing, watershedswatershedswatershedsWatershedsWatersheds, class_ndim_normclass_ndim_normclass_ndim_normClassNdimNormClassNdimNorm

Possible Successors

reduce_domainreduce_domainreduce_domainReduceDomainReduceDomain, select_shapeselect_shapeselect_shapeSelectShapeSelectShape, area_centerarea_centerarea_centerAreaCenterAreaCenter, connectionconnectionconnectionConnectionConnection

Alternatives

erosion_seqerosion_seqerosion_seqErosionSeqErosionSeq, erosion1erosion1erosion1Erosion1Erosion1, erosion2erosion2erosion2Erosion2Erosion2

See also

dilation_golaydilation_golaydilation_golayDilationGolayDilationGolay, opening_golayopening_golayopening_golayOpeningGolayOpeningGolay, closing_golayclosing_golayclosing_golayClosingGolayClosingGolay, hit_or_miss_golayhit_or_miss_golayhit_or_miss_golayHitOrMissGolayHitOrMissGolay, thinning_golaythinning_golaythinning_golayThinningGolayThinningGolay, thickening_golaythickening_golaythickening_golayThickeningGolayThickeningGolay, golay_elementsgolay_elementsgolay_elementsGolayElementsGolayElements

Module

Foundation