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AVL.FitCircleToEdges_Direct

Namespace:AvlNet
Assembly:AVL.NET.dll

Syntax

C++
C#
 
public static void FitCircleToEdges_Direct
(
	AvlNet.Image inImage,
	AvlNet.CircleFittingField inFittingField,
	AvlNet.CoordinateSystem2D? inFittingFieldAlignment,
	int inScanCount,
	int inScanWidth,
	AvlNet.SamplingParams inSamplingParams,
	AvlNet.EdgeScanParams inEdgeScanParams,
	AvlNet.Selection inEdgeSelection,
	AvlNet.LocalBlindness? inLocalBlindness,
	float inMaxIncompleteness,
	AvlNet.CircleFittingMethod inFittingMethod,
	AvlNet.MEstimator? inOutlierSuppression,
	out AvlNet.Circle2D? outCircle,
	NullableRef<List<AvlNet.Edge1D?>> outEdges,
	NullableRef<NullableRef<AvlNet.Profile>> outDeviationProfile,
	NullableValue<AvlNet.CircleFittingField> outAlignedFittingField,
	NullableRef<List<AvlNet.Point2D>> outInliers,
	NullableRef<SafeList<AvlNet.Profile>> outBrightnessProfiles,
	NullableRef<SafeList<AvlNet.Profile>> outResponseProfiles,
	IList<AvlNet.Segment2D> diagScanSegments,
	IList<AvlNet.Rectangle2D> diagSamplingAreas
)

Parameters

Name Type Range Default Description
inImageAvlNet.ImageImage to fit the circle to
inFittingFieldAvlNet.CircleFittingFieldCircle fitting field
inFittingFieldAlignmentAvlNet.CoordinateSystem2D?Adjusts the fitting field to the position of the inspected object
inScanCountint<3, INF>10The number of points that will be searched to estimate the position of the circle
inScanWidthint<1, INF>5The width of each scan field (in pixels)
inSamplingParamsAvlNet.SamplingParamsParameters controlling the sampling process
inEdgeScanParamsAvlNet.EdgeScanParamsEdgeScanParams ( ProfileInterpolation: Quadratic4 SmoothingStdDev: 1.0f MinMagnitude: 5.0f EdgeTransition: BrightToDark )Parameters controlling the edge extraction process
inEdgeSelectionAvlNet.SelectionSelection mode of edges
inLocalBlindnessAvlNet.LocalBlindness?Defines conditions in which weaker edges can be detected in the vicinity of stronger edges
inMaxIncompletenessfloat<0.0f, 0.999f>0.1fMaximal fraction of edge points not found
inFittingMethodAvlNet.CircleFittingMethodAlgebraicTaubinMethod used to fit a circle
inOutlierSuppressionAvlNet.MEstimator?Selects a method for ignoring incorrectly detected points
outCircleAvlNet.Circle2D?Fitted circle or nothing if the fitting fails
outEdgesAvlNet.NullableRef<System.Collections.Generic.List<AvlNet.Edge1D?>>Found edges
outDeviationProfileAvlNet.NullableRef<AvlNet.NullableRef<AvlNet.Profile>>Profile of distances between the actual circle points and the corresponding reference circle points
outAlignedFittingFieldAvlNet.NullableValue<AvlNet.CircleFittingField>Fitting field used; in the image coordinate system
outInliersAvlNet.NullableRef<System.Collections.Generic.List<AvlNet.Point2D>>Points matching the fitting Circle
outBrightnessProfilesAvlNet.NullableRef<AvlNet.SafeList<AvlNet.Profile>>Extracted image profiles
outResponseProfilesAvlNet.NullableRef<AvlNet.SafeList<AvlNet.Profile>>Profiles of the edge (derivative) operator response
diagScanSegmentsSystem.Collections.Generic.IList<AvlNet.Segment2D>Segments along which the scans were run
diagSamplingAreasSystem.Collections.Generic.IList<AvlNet.Rectangle2D>Areas from which the input image is sampled

Description

The operation tries to fit a given circle to edges present in the inImage image. Internally, it performs a series of scans with the ScanSingleEdge_Direct filter along inScanCount specific scan segments which length is always equal to the inFittingField width and cannot be less than 4. The found points are then used to determine the actual position of the circle in the image. Only inMaxIncompleteness fraction of these scans may fail. If the fitting according to the given parameters is not possible, outCircle is set to Nil.

Examples

Fitting a circles to the edges of a hole
(inEdgeScanParams.Transition = BrightToDark).

Remarks

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

This filter is a part of the Shape Fitting toolset. To read more about this technique, one can refer to the Shape Fitting chapter of our Machine Vision Guide

Hardware Acceleration

This operation supports automatic parallelization for multicore and multiprocessor systems.

Hardware acceleration settings may be manipulated with Settings class.

Function Overrides

See also