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AVL.DetectMultipleCircles Method

Finds circles of a given radius in the input image.

Namespace:	AvlNet
Assembly:	AVL.NET.dll

Syntax

public static void DetectMultipleCircles(
	AvlNet.Image inImage,
	AvlNet.Region inRoi,
	float inRadius,
	float inMaxOverlap,
	float inMinScore,
	float inEdgeThreshold,
	out AvlNet.HoughCircle[] outCircles,
	out AvlNet.Image diagGradientMagnitudeImage,
	out AvlNet.Image diagScoreImage
)

Parameters

Name	Type	Range	Default	Description
inImage	AvlNet.Image			Input image.
inRoi	AvlNet.Region			Input region of interest. Default value: atl::NIL, or null.
inRadius	float	<0.0f, INF>	10.0f	Circles' radius. Default value: 10.0f.
inMaxOverlap	float	<0.0f, 1.0f>	0.1f	Maximum accepted overlapping coefficient. Default value: 0.1f.
inMinScore	float	<0.0f, INF>	20.0f	Minimum matching score. Default value: 20.0f.
inEdgeThreshold	float		10.0f	Minimum accepted edge magnitude. Default value: 10.0f.
outCircles	AvlNet.HoughCircle			Found circles.
diagGradientMagnitudeImage	AvlNet.Image			Visualized gradients magnitude of an input image.
diagScoreImage	AvlNet.Image			Calculated score for each pixel of an input image.

Description

The operation detects circular objects of given radius (in pixels) in the inImage using the Hough Transform approach. The output array is ordered from best matching to worst matching results.

The parameter inMaxOverlap defines how much the detected circles can overlap. The value of 0 means no overlapping is allowed, and also that each circle must be fully contained in the search ROI, whereas the value of 1 allows full overlapping.

Examples

DetectMultipleCircles performed on the sample image.

Hardware Acceleration

This operation supports automatic parallelization for multicore and multiprocessor systems.