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AVL.FitCircleToRidges_Direct

Performs a series of 1D ridge detections and finds a circle that best matches the detected points.

Namespace:AvlNet
Assembly:AVL.NET.dll

Syntax

C++
C#
 
public static void FitCircleToRidges_Direct
(
	AvlNet.Image inImage,
	AvlNet.CircleFittingField inFittingField,
	AvlNet.CoordinateSystem2D? inFittingFieldAlignment,
	int inScanCount,
	int inScanWidth,
	AvlNet.SamplingParams inSamplingParams,
	AvlNet.RidgeScanParams inRidgeScanParams,
	AvlNet.Selection inRidgeSelection,
	AvlNet.LocalBlindness? inLocalBlindness,
	float inMaxIncompleteness,
	AvlNet.CircleFittingMethod inFittingMethod,
	AvlNet.MEstimator? inOutlierSuppression,
	out AvlNet.Circle2D? outCircle,
	IList<AvlNet.Ridge1D?> outRidges,
	INullable<AvlNet.Profile> outDeviationProfile,
	out AvlNet.CircleFittingField outAlignedFittingField,
	IList<AvlNet.Point2D> outInliers,
	IList<AvlNet.Profile> outBrightnessProfiles,
	IList<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. Default value: atl::NIL.
inScanCountint<3, INF>10The number of points that will be searched to estimate the position of the circle. Default value: 10.
inScanWidthint<1, INF>5The width of each scan field (in pixels). Default value: 5.
inSamplingParamsAvlNet.SamplingParamsParameters controlling the sampling process.
inRidgeScanParamsAvlNet.RidgeScanParamsRidgeScanParams ( ProfileInterpolation: Quadratic4 SmoothingStdDev: 1.0f RidgeWidth: 5 RidgeMargin: 2 MinMagnitude: 5.0f RidgePolarity: Dark )Parameters controlling the ridge extraction process. Default value: RidgeScanParams ( ProfileInterpolation: Quadratic4 SmoothingStdDev: 1.0f RidgeWidth: 5 RidgeMargin: 2 MinMagnitude: 5.0f RidgePolarity: Dark ).
inRidgeSelectionAvlNet.SelectionSelection mode of ridges.
inLocalBlindnessAvlNet.LocalBlindness?Defines conditions in which weaker ridges can be detected in the vicinity of stronger ridges. Default value: atl::NIL.
inMaxIncompletenessfloat<0.0f, 0.999f>0.1fMaximal fraction of ridge points not found. Default value: 0.1f.
inFittingMethodAvlNet.CircleFittingMethodAlgebraicTaubinMethod used to fit a circle. Default value: AlgebraicTaubin.
inOutlierSuppressionAvlNet.MEstimator?Selects a method for ignoring incorrectly detected points. Default value: atl::NIL.
outCircleAvlNet.Circle2D?Fitted circle or nothing if the fitting fails.
outRidgesSystem.Collections.Generic.IList<AvlNet.Ridge1D?>Found ridges.
outDeviationProfileAvlNet.INullable<AvlNet.Profile>Profile of distances between the actual circle points and the corresponding reference circle points. This parameter cannot be null.
outAlignedFittingFieldAvlNet.CircleFittingFieldFitting field used; in the image coordinate system.
outInliersSystem.Collections.Generic.IList<AvlNet.Point2D>Points matching the fitting Circle.
outBrightnessProfilesSystem.Collections.Generic.IList<AvlNet.Profile>Extracted image profiles.
outResponseProfilesSystem.Collections.Generic.IList<AvlNet.Profile>Profiles of the ridge 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 ridges present in the inImage image. Internally, it performs a series of scans with the ScanSingleRidge_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 circle to a wall of a plastic capsule
(inRidgeScanParams.Polarity = Dark, inRidgeScanParams.RidgeWidth = 3).

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