Collection of functions for edge detection. More...

Classes
class	EdgeResult
	Edge search result More...

class	EdgeResultPair
	A pair of found edges. More...

class	Projection
	Projection that the Edge analysis of Common Vision Blox is using. More...

class	ProjectionValue
	Single projection value. More...

Typedefs
typedef std::shared_ptr< Projection >	ProjectionPtr
	Convenience shared pointer for Projection.

Enumerations
enum class	EdgeSearchMode { Intensity , IntensitySubPixel , Contrast , ContrastSubPixel , SecondDerivativeSubPixel }
	Determines the algorithm for finding an edge. More...

enum class	EdgeType { Ignore = CExports::POLARITY_DONT_CARE , Positive = CExports::POLARITY_POSITIVE , Negative = CExports::POLARITY_NEGATIVE }
	Type of the edges to be searched. More...

enum class	ProjectionMode { Average , Sum }
	Options affecting the result of the projection. More...

Functions
bool	operator!= (const EdgeResult &lhs, const EdgeResult &rhs) noexcept
	Comparison operator for EdgeResult objects.

bool	operator== (const EdgeResult &lhs, const EdgeResult &rhs) noexcept
	Comparison operator for EdgeResult objects.

EdgeResult	FindFirstEdge (const ImagePlane &plane, EdgeSearchMode mode, EdgeType type, double threshold, Area2D aoi, double density=1.0)
	Find the first edge (as specified) in the aoi.

EdgeResult	FindFirstEdge (const ImagePlane &plane, EdgeSearchMode mode, EdgeType type, double threshold, double density=1.0)
	Find the first edge (as specified) in the whole plane.

EdgeResultPair	FindEdgePair (const ImagePlane &plane, EdgeSearchMode mode, EdgeType type1, double threshold1, EdgeType type2, double threshold2, Area2D aoi, double density=1.0)
	Find an edge pair (as specified) in the aoi.

EdgeResultPair	FindEdgePair (const ImagePlane &plane, EdgeSearchMode mode, EdgeType type1, double threshold1, EdgeType type2, double threshold2, double density=1.0)
	Find an edge pair (as specified) in the whole plane.

EdgeResultPair	FindEdgePair (const ImagePlane &plane, EdgeSearchMode mode, EdgeType type1, EdgeType type2, double threshold, Area2D aoi, double density=1.0)
	Find an edge pair (as specified) in the aoi.

EdgeResultPair	FindEdgePair (const ImagePlane &plane, EdgeSearchMode mode, EdgeType type1, EdgeType type2, double threshold, double density=1.0)
	Find an edge pair (as specified) in the whole plane.

std::vector< EdgeResult >	FindAllEdges (const ImagePlane &plane, EdgeSearchMode mode, EdgeType type, double threshold, Area2D aoi, double density=1.0)
	Find all edges inside the aoi.

std::vector< EdgeResult >	FindAllEdges (const ImagePlane &plane, EdgeSearchMode mode, EdgeType type, double threshold, double density=1.0)
	Find all edges inside the whole plane.

EdgeResult	FindBestEdge (const ImagePlane &plane, EdgeType type, Area2D aoi, double density=1.0)
	Use the 2nd derivative method to find the edge with the highest intensity in the area of interest.

EdgeResult	FindBestEdge (const ImagePlane &plane, EdgeType type, double density=1.0)
	Use the 2nd derivative method to find the edge with the highest intensity in the whole plane.

void	WriteProjection (const ImagePlane &plane, Area2D aoi, double density=1.0)
	Write the projection that Edge is using internally as the basis for its calculations into an image plane (might be useful for debugging).

Detailed Description

Collection of functions for edge detection.

Online Manual: Image Analysis

Remarks: CMake users: Link to imported target CVB::CvbFoundationEdge

Enumeration Type Documentation

◆ EdgeSearchMode

enum class EdgeSearchMode

strong

Determines the algorithm for finding an edge.

Enumerator
Intensity	Find edges based on absolute intensities in the image. In this mode, the edge quality directly corresponds to the difference in intensity across the edge.
IntensitySubPixel	Like Intensity, but with sub pixel accuracy.
Contrast	Find edges based on the contrasts in the image (1st derivative of the gray values).
ContrastSubPixel	Like Contrast, but with sub pixel accuracy.
SecondDerivativeSubPixel	Find edges based on the 2nd derivative of the intensities with sub pixel accuracy. Note that in this mode edge qualities are usually much lower than 10.

◆ EdgeType

enum class EdgeType

strong

Type of the edges to be searched.

Enumerator
Ignore	Used for EdgeResult::Nothing and with the 2nd derivative edge detection functions.
Positive	Intensities increase along the scan direction.
Negative	Intensities decrease along the scan direction.

◆ ProjectionMode

enum class ProjectionMode

strong

Options affecting the result of the projection.

Enumerator
Average	Projection value is the average value per projection line.
Sum	Projection value is the sum of all gray values per projection line.

Function Documentation

◆ FindAllEdges() [1/2]

std::vector< EdgeResult > FindAllEdges	(	const ImagePlane &	plane,
		EdgeSearchMode	mode,
		EdgeType	type,
		double	threshold,
		Area2D	aoi,
		double	density = 1.0 )

inline

Find all edges inside the aoi.

Parameters

[in]	plane	Plane in which to search.
[in]	mode	Search mode to use.
[in]	type	Type of edge to be searched for.
[in]	threshold	Threshold to apply.
[in]	aoi	Area to scan.
[in]	density	Search density to use where 1.0 means scanning all pixels.

Returns: Found edges.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindAllEdges() [2/2]

std::vector< EdgeResult > FindAllEdges	(	const ImagePlane &	plane,
		EdgeSearchMode	mode,
		EdgeType	type,
		double	threshold,
		double	density = 1.0 )

inline

Find all edges inside the whole plane.

Parameters

[in]	plane	Plane in which to search.
[in]	mode	Search mode to use.
[in]	type	Type of edge to be searched for.
[in]	threshold	Threshold to apply.
[in]	density	Search density to use where 1.0 means scanning all pixels.

Returns: Found edges.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindBestEdge() [1/2]

EdgeResult FindBestEdge	(	const ImagePlane &	plane,
		EdgeType	type,
		Area2D	aoi,
		double	density = 1.0 )

inline

Use the 2nd derivative method to find the edge with the highest intensity in the area of interest.

Parameters

[in]	plane	Plane to scan.
[in]	type	Type of edge to be searched for.
[in]	aoi	Area to scan.
[in]	density	Density at which to scan the aoi where 1.0 means scanning all pixels.

Returns: The best result (or EdgeResult::Nothing() if nothing was found e.g. because the area is outside the image).

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindBestEdge() [2/2]

EdgeResult FindBestEdge	(	const ImagePlane &	plane,
		EdgeType	type,
		double	density = 1.0 )

inline

Use the 2nd derivative method to find the edge with the highest intensity in the whole plane.

Parameters

[in]	plane	Plane to scan.
[in]	type	Type of edge to be searched for.
[in]	density	Density at which to scan the plane where 1.0 means scanning all pixels.

Returns: The best result (or EdgeResult::Nothing() if nothing was found e.g. because the area is outside the image).

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindEdgePair() [1/4]

EdgeResultPair FindEdgePair	(	const ImagePlane &	plane,
		EdgeSearchMode	mode,
		EdgeType	type1,
		double	threshold1,
		EdgeType	type2,
		double	threshold2,
		Area2D	aoi,
		double	density = 1.0 )

inline

Find an edge pair (as specified) in the aoi.

Parameters

[in]	plane	Plane to search in.
[in]	mode	Search mode.
[in]	type1	Type of edge to be searched for.
[in]	threshold1	Threshold to apply when looking for the first edge (left to right in the aoi).
[in]	type2	Type of edge to be searched for.
[in]	threshold2	Threshold to apply when looking for the second edge (right to left in the aoi).
[in]	aoi	Area to scan.
[in]	density	Density at which to scan the aoi where 1.0 means scanning all pixels.

Returns: Search results (containing EdgeResult::Nothing() if not found).

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindEdgePair() [2/4]

EdgeResultPair FindEdgePair	(	const ImagePlane &	plane,
		EdgeSearchMode	mode,
		EdgeType	type1,
		double	threshold1,
		EdgeType	type2,
		double	threshold2,
		double	density = 1.0 )

inline

Find an edge pair (as specified) in the whole plane.

Parameters

[in]	plane	Plane to search in.
[in]	mode	Search mode.
[in]	type1	Type of edge to be searched for.
[in]	threshold1	Threshold to apply when looking for the first edge (left to right in the plane).
[in]	type2	Type of edge to be searched for.
[in]	threshold2	Threshold to apply when looking for the second edge (right to left in the plane).
[in]	density	Density at which to scan the plane where 1.0 means scanning all pixels.

Returns: Search results (containing EdgeResult::Nothing() if not found).

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindEdgePair() [3/4]

EdgeResultPair FindEdgePair	(	const ImagePlane &	plane,
		EdgeSearchMode	mode,
		EdgeType	type1,
		EdgeType	type2,
		double	threshold,
		Area2D	aoi,
		double	density = 1.0 )

inline

Find an edge pair (as specified) in the aoi.

Parameters

[in]	plane	Plane to search in.
[in]	mode	Search mode.
[in]	type1	Type of edge to be searched for.
[in]	type2	Type of edge to be searched for.
[in]	threshold	Threshold to apply when looking for for both edges.
[in]	aoi	Area to scan.
[in]	density	Density at which to scan the aoi where 1.0 means scanning all pixels.

Returns: Search results (containing EdgeResult::Nothing() if not found).

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindEdgePair() [4/4]

EdgeResultPair FindEdgePair	(	const ImagePlane &	plane,
		EdgeSearchMode	mode,
		EdgeType	type1,
		EdgeType	type2,
		double	threshold,
		double	density = 1.0 )

inline

Find an edge pair (as specified) in the whole plane.

Parameters

[in]	plane	Plane to search in.
[in]	mode	Search mode.
[in]	type1	Type of edge to be searched for.
[in]	type2	Type of edge to be searched for.
[in]	threshold	Threshold to apply when looking for for both edges.
[in]	density	Density at which to scan the aoi where 1.0 means scanning all pixels.

Returns: Search results (containing EdgeResult::Nothing() if not found).

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindFirstEdge() [1/2]

EdgeResult FindFirstEdge	(	const ImagePlane &	plane,
		EdgeSearchMode	mode,
		EdgeType	type,
		double	threshold,
		Area2D	aoi,
		double	density = 1.0 )

inline

Find the first edge (as specified) in the aoi.

Parameters

[in]	plane	Plane to search in.
[in]	mode	Search mode.
[in]	type	Type of edge to be searched for.
[in]	threshold	Edge threshold to apply.
[in]	aoi	Area to scan.
[in]	density	Density at which to scan the aoi where 1.0 means scanning all pixels.

Returns: Found edge (or EdgeResult::Nothing() if no edge was found).

Exceptions

Any	exception derived from std::exception including CvbException.

◆ FindFirstEdge() [2/2]

EdgeResult FindFirstEdge	(	const ImagePlane &	plane,
		EdgeSearchMode	mode,
		EdgeType	type,
		double	threshold,
		double	density = 1.0 )

inline

Find the first edge (as specified) in the whole plane.

Parameters

[in]	plane	Plane to search in.
[in]	mode	Search mode.
[in]	type	Type of edge to be searched for.
[in]	threshold	Edge threshold to apply.
[in]	density	Density at which to scan the plane where 1.0 means scanning all pixels.

Returns: Found edge (or EdgeResult::Nothing() if no edge was found).

Exceptions

Any	exception derived from std::exception including CvbException.

◆ operator!=()

bool operator!=	(	const EdgeResult &	lhs,
		const EdgeResult &	rhs )

inlinenoexcept

Comparison operator for EdgeResult objects.

Parameters

[in]	lhs	Left hand side operand.
[in]	rhs	Right hand side operand.

Returns: True if lhs != rhs, false otherwise.

Exceptions

Does	not throw any exception.

◆ operator==()

bool operator==	(	const EdgeResult &	lhs,
		const EdgeResult &	rhs )

inlinenoexcept

Comparison operator for EdgeResult objects.

Parameters

[in]	lhs	Left hand side operand.
[in]	rhs	Right hand side operand.

Returns: True if lhs == rhs, false otherwise.

Exceptions

Does	not throw any exception.

◆ WriteProjection()

void WriteProjection	(	const ImagePlane &	plane,
		Area2D	aoi,
		double	density = 1.0 )

inline

Write the projection that Edge is using internally as the basis for its calculations into an image plane (might be useful for debugging).

Parameters

[in]	plane	Plane to write the projection to.
[in]	aoi	Area of interest to project.
[in]	density	Density at which to scan where 1.0 means scanning all pixels.

Exceptions

Any	exception derived from std::exception including CvbException.

Classes

Typedefs

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

◆ EdgeSearchMode

◆ EdgeType

◆ ProjectionMode

Function Documentation

◆ FindAllEdges() [1/2]

◆ FindAllEdges() [2/2]

◆ FindBestEdge() [1/2]

◆ FindBestEdge() [2/2]

◆ FindEdgePair() [1/4]

◆ FindEdgePair() [2/4]

◆ FindEdgePair() [3/4]

◆ FindEdgePair() [4/4]

◆ FindFirstEdge() [1/2]

◆ FindFirstEdge() [2/2]

◆ operator!=()

◆ operator==()

◆ WriteProjection()