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Header: AVL.h
Namespace: avl
Module: MetrologyBasic

Precomputes a data object that is required for fast 1D edge detection.

Applications: Used together with 1D Edge Detection filters (excluding "_Direct"), but can be moved before the loop if only the scan parameters do not change.


void avl::CreateScanMap
	const avl::ImageFormat& inImageFormat,
	const avl::Path& inScanPath,
	atl::Optional<const avl::CoordinateSystem2D&> inScanPathAlignment,
	int inScanWidth,
	const avl::SamplingParams& inSamplingParams,
	avl::ScanMap& outScanMap,
	atl::Optional<avl::Path&> outAlignedScanPath = atl::NIL,
	atl::Array<avl::Path>& diagSamplingPoints,
	float& diagSamplingStep


Name Type Range Default Description
Input value
inImageFormat const ImageFormat& Dimensions, depth and pixel type of the image on which edge detection will be performed
Input value
inScanPath const Path& Path along which the scan is performed
Input value
inScanPathAlignment Optional<const CoordinateSystem2D&> NIL Adjusts the scan path to the position of the inspected object
Input value
inScanWidth int 1 - 5 Width of the scan field in pixels
Input value
inSamplingParams const SamplingParams& .interpolation Bilinear Parameters controlling the sampling process
Output value
outScanMap ScanMap& Optimized data object required for 1D edge detection
Output value
outAlignedScanPath Optional<Path&> NIL Transformed input path
Diagnostic input
diagSamplingPoints Array<Path>& Array of paths each one containing the sampling points that contributes to a single value of the extracted profile
Diagnostic input
diagSamplingStep float& Used distance between consecutive sampling points on the scan path

Optional Outputs

The computation of following outputs can be switched off by passing value atl::NIL to these parameters: outAlignedScanPath.

Read more about Optional Outputs.


The operation creates a scan map from a given inScanPath. The scan map can be later used by other 1D Edge Detection filters.

The optional parameter inScanPathAlignment defines a transform to be performed on the inScanPath so that the actual scan path (outAlignedScanPath) is adjusted to the position of the object, typically detected by one of Template Matching filters.

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.


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

See Also

  • ScanSingleEdge – Locates the strongest transition between dark and bright pixels along a given path.
  • ScanSingleRidge – Locates the strongest dark or bright pixel peak along a given path.