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AVL.ScanExactlyNEdges

Locates a specified number of the strongest transitions between dark and bright pixels along a given path.

Namespace:AvlNet
Assembly:AVL.NET.dll

Syntax

C++
C#
 
public static void ScanExactlyNEdges
(
	AvlNet.Image inImage,
	AvlNet.ScanMap inScanMap,
	AvlNet.EdgeScanParams inEdgeScanParams,
	int inEdgeCount,
	AvlNet.Selection inEdgeSelection,
	float inMinDistance,
	INullable<List<AvlNet.Edge1D>> outEdges,
	INullable<List<AvlNet.Gap1D>> outGaps
)

Parameters

Name Type Range Default Description
inImageAvlNet.ImageInput image.
inScanMapAvlNet.ScanMapData precomputed with CreateScanMap.
inEdgeScanParamsAvlNet.EdgeScanParamsEdgeScanParams ( ProfileInterpolation: Quadratic4 SmoothingStdDev: 0.6f MinMagnitude: 5.0f EdgeTransition: BrightToDark )Parameters controlling the edge extraction process. Default value: EdgeScanParams ( ProfileInterpolation: Quadratic4 SmoothingStdDev: 0.6f MinMagnitude: 5.0f EdgeTransition: BrightToDark ).
inEdgeCountint<0, INF>1Number of edges to be found. Default value: 1.
inEdgeSelectionAvlNet.Selectionavl::Selection::BestSelection mode of the resulting edges. Default value: avl::Selection::Best.
inMinDistancefloat<0.0f, INF>0.0fMinimal distance between consecutive edges. Default value: 0.0f.
outEdgesAvlNet.INullable<System.Collections.Generic.List<AvlNet.Edge1D>>Found edges. This parameter cannot be null.
outGapsAvlNet.INullable<System.Collections.Generic.List<AvlNet.Gap1D>>Gaps between consecutive edges. This parameter cannot be null.

Description

The operation scans the image using inScanMap previously generated from a scan path and finds a set of inEdgeCount image edges perpendicular to the path. If no subset (of inEdgeCount elements) of detected edges meets the requirements of inEdgeScanParams.minMagnitude, inMinDistance, inEdgeScanParams.edgeTransition then the outputs are set to NIL.

Note that in case of a scan path which is closed, the parameters controlling the distances between consecutive found objects do not control the distance between the first and the last of the found objects (counting from the beginning of the scan path).

Examples

ScanExactlyNEdges locates the edges using a scan map representing the scan path above (inEdgeCount = 61).

Remarks

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

This filter is a part of the 1D Edge Detection toolset. For a comprehensive introduction to this technique please refer to 1D Edge Detection and 1D Edge Detection - Subpixel Precision chapters of our Machine Vision Guide.

Function Overrides

See also