You are here: Start » AVL.NET » Function Reference » Computer Vision » Shape Fitting » AVL.FitArcToRidges_Direct

AVL.FitArcToRidges_Direct

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

Namespace:AvlNet
Assembly:AVL.NET.dll

Syntax

C++
C#
 
public static void FitArcToRidges_Direct
(
	AvlNet.Image inImage,
	AvlNet.ArcFittingField 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.Arc2D? outArc,
	NullableRef<List<AvlNet.Ridge1D?>> outRidges,
	NullableRef<NullableRef<AvlNet.Profile>> outDeviationProfile,
	INullable<AvlNet.ArcFittingField> outAlignedFittingField,
	NullableRef<List<AvlNet.Point2D>> outInliers,
	NullableRef<SafeList<AvlNet.Profile>> outBrightnessProfiles,
	NullableRef<SafeList<AvlNet.Profile>> outResponseProfiles
)

Parameters

Name Type Range Default Description
inImageAvlNet.ImageInput image to fit arc to.
inFittingFieldAvlNet.ArcFittingFieldArc 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 arc. 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 an arc. Default value: AlgebraicTaubin.
inOutlierSuppressionAvlNet.MEstimator?Selects a method for ignoring incorrectly detected points. Default value: atl::NIL.
outArcAvlNet.Arc2D?Fitted arc or nothing if the fitting fails.
outRidgesAvlNet.NullableRef<System.Collections.Generic.List<AvlNet.Ridge1D?>>Found ridges. Can be null to skip this parameter calculation.
outDeviationProfileAvlNet.NullableRef<AvlNet.NullableRef<AvlNet.Profile>>Profile of distances between the actual arc points and the corresponding reference arc points. Can be null to skip this parameter calculation.
outAlignedFittingFieldAvlNet.INullable<AvlNet.ArcFittingField>Fitting field used; in the image coordinate system. Can be null to skip this parameter calculation.
outInliersAvlNet.NullableRef<System.Collections.Generic.List<AvlNet.Point2D>>Points matching the fitting Arc. Can be null to skip this parameter calculation.
outBrightnessProfilesAvlNet.NullableRef<AvlNet.SafeList<AvlNet.Profile>>Extracted image profiles. Can be null to skip this parameter calculation.
outResponseProfilesAvlNet.NullableRef<AvlNet.SafeList<AvlNet.Profile>>Profiles of the ridge operator response. Can be null to skip this parameter calculation.

Description

The operation tries to fit a given arc 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 arc in the image. Only inMaxIncompleteness fraction of these scans may fail. If the fitting according to the given parameters is not possible, outArc is set to Nil.

Examples

Fitting an arc to a curved wall of a plastic capsule
(inRidgeScanParams.RidgeWidth = 3, inRidgeScanParams.Polarity = Dark).

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