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FIL.ScanExactlyNEdges3D

Locates a specified number of the strongest changes of surface height along a given path.

Namespace:FilNet
Assembly:FIL.NET.dll

Syntax

C++
C#
 
public static void ScanExactlyNEdges3D
(
	FilNet.Surface inSurface,
	FilNet.ScanMap inScanMap,
	FilNet.EdgeScanParams3D inEdgeScanParams,
	int inEdgeCount,
	FilNet.Selection inEdgeSelection,
	float inMinDistance,
	float? inMaxDistance,
	FilNet.LocalBlindness? inLocalBlindness,
	int? inMaxProfileGapWidth,
	INullable<List<FilNet.SurfaceEdge1D>> outEdges,
	FilNet.Profile outHeightProfile,
	FilNet.Profile outResponseProfile
)

Parameters

Name Type Range Default Description
inSurfaceFilNet.SurfaceInput surface.
inScanMapFilNet.ScanMapData precomputed with CreateSurfaceScanMap.
inEdgeScanParamsFilNet.EdgeScanParams3DParameters controlling the surface edge extraction process.
inEdgeCountint<0, INF>1Number of surface edges to be found. Default value: 1.
inEdgeSelectionFilNet.Selectionfil::Selection::BestSelection mode of the resulting edges. Default value: fil::Selection::Best.
inMinDistancefloat<0.0f, INF>0.0fMinimal distance between consecutive edges. Default value: 0.0f.
inMaxDistancefloat?<0.0f, INF>Maximal distance between consecutive edges. Default value: ftl::NIL.
inLocalBlindnessFilNet.LocalBlindness?Defines conditions in which weaker edges can be detected in the vicinity of stronger edges. Default value: ftl::NIL.
inMaxProfileGapWidthint?<0, INF>1Maximal number of consecutive not existing profile points. Default value: 1.
outEdgesFilNet.INullable<System.Collections.Generic.List<FilNet.SurfaceEdge1D>>Found surface edges. This parameter cannot be null.
outHeightProfileFilNet.ProfileExtracted surface height profile.
outResponseProfileFilNet.ProfileProfile of the edge (derivative) operator response.

Description

The operation scans the surface using inScanMap previously generated from a scan path and finds a set of inEdgeCount surface edges perpendicular to the path. If no subset (of inEdgeCount elements) of detected edges meets the requirements of inEdgeScanParams.minMagnitude, inMinDistance, inEdgeScanParams.edgeTransition then the outputs are set to NIL.

Note that in case of a scan path which is closed, the parameters controlling the distances between consecutive found objects do not control the distance between the first and the last of the found objects (counting from the beginning of the scan path).

The operation is very similar to ScanExactlyNEdges from 1DEdgeDetection category, but there are some substantial differences. One of these is the possibility of absence of information, because some surface points may not exist at all. To detect such edges, where solely change of existence matters, Valid/Invalid options of inEdgeScanParams.EdgeTransition can be used. Outside the surface domain (i.e. rectangle defined by input surface width, height, offsets and scales) there are no valid or invalid points, so no edge can be found in the direct vicinity of the domain border.

Because in the Valid/Invalid mode all edges have equal strength, if inEdgeSelection is set to Best, it will be implicitly substituted with First selection option.

Please note that when the input surface has unequal scales along X and Y axes and the scan path is not parallel to any of the axes, the results may be slightly less accurate because of uneven sampling along axes.

Remarks

Read more about Local Coordinate Systems in Machine Vision Guide: Local Coordinate Systems.

Function Overrides

See also