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AVL.ScanSingleEdge3D_Direct

Locates the strongest change of surface height along a given path.

Namespace:AvlNet
Assembly:AVL.NET.dll

Syntax

C++
C#
 
public static void ScanSingleEdge3D_Direct
(
	AvlNet.Surface inSurface,
	AvlNet.Path inScanPath,
	AvlNet.CoordinateSystem2D? inScanPathAlignment,
	float? inSamplingStep,
	int inScanWidth,
	AvlNet.InterpolationMethod inSurfaceInterpolation,
	AvlNet.EdgeScanParams3D inEdgeScanParams,
	AvlNet.Selection inEdgeSelection,
	AvlNet.LocalBlindness? inLocalBlindness,
	int? inMaxProfileGapWidth,
	out AvlNet.SurfaceEdge1D? outEdge
)

Parameters

Name Type Range Default Description
inSurfaceAvlNet.SurfaceInput surface.
inScanPathAvlNet.PathPath along which the scan is performed.
inScanPathAlignmentAvlNet.CoordinateSystem2D?Adjusts the scan path to the position of the inspected object. Default value: atl::NIL.
inSamplingStepfloat?<0.0f, INF>Distance between consecutive sampling points on the scan path; if Nil, the bigger of surface X and Y scales is chosen. Default value: atl::NIL.
inScanWidthint<1, INF>5Width of the scan field in pixels. Default value: 5.
inSurfaceInterpolationAvlNet.InterpolationMethodBilinearInterpolation method used for extraction of surface points. Default value: Bilinear.
inEdgeScanParamsAvlNet.EdgeScanParams3DEdgeScanParams3D ( ProfileInterpolation: Quadratic4 SmoothingStdDev: 0.6f MinMagnitude: 5.0f EdgeTransition: LowToHigh )Parameters controlling the surface edge extraction process. Default value: EdgeScanParams3D ( ProfileInterpolation: Quadratic4 SmoothingStdDev: 0.6f MinMagnitude: 5.0f EdgeTransition: LowToHigh ).
inEdgeSelectionAvlNet.SelectionIf many edge points are possible, defines which one is selected.
inLocalBlindnessAvlNet.LocalBlindness?Defines conditions in which weaker edges can be detected in the vicinity of stronger edges. Default value: atl::NIL.
inMaxProfileGapWidthint?<0, INF>1Maximal number of consecutive not existing profile points. Default value: 1.
outEdgeAvlNet.SurfaceEdge1D?Found surface edge.

Description

The operation scans the surface along inScanPath and locates the strongest edge perpendicular to the path. If the strongest edge is weaker than inEdgeScanParams.minMagnitude then the outputs are set to NIL.

The optional parameter inScanPathAlignment defines a transform to be performed on the inScanPath so that the actual scan path (outAlignedScanPath) is adjusted to the position of the object.

The operation is very similar to ScanSingleEdge 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