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CheckPresence_Intensity

Verifies object presence by analysing pixel intensities in the specified region.

Header:	AVL.h

Syntax

void avl::CheckPresence_Intensity
(
	const avl::Image& inImage,
	const avl::ShapeRegion& inRoi,
	atl::Optional<const avl::CoordinateSystem2D&> inRoiAlignment,
	atl::Optional<float> inMinIntensity,
	atl::Optional<float> inMaxIntensity,
	float inMinContrast,
	atl::Optional<float> inMaxContrast,
	bool& outIsPresent,
	atl::Optional<float&> outIntensity = atl::NIL,
	atl::Optional<float&> outContrast = atl::NIL,
	atl::Optional<avl::ShapeRegion&> outAlignedRoi = atl::NIL
)

void CheckPresence_Intensity
(
	Image inImage,
	ShapeRegion inRoi,
	CoordinateSystem2D? inRoiAlignment,
	float? inMinIntensity,
	float? inMaxIntensity,
	float inMinContrast,
	float? inMaxContrast,
	out bool outIsPresent,
	out float? outIntensity,
	out float? outContrast,
	out ShapeRegion? outAlignedRoi
)

Parameters

Name	Type	Range	Default	Description
inImage	const Image&			Input image
inRoi	const ShapeRegion&			Location at which object presence is being checked
inRoiAlignment	Optional<const CoordinateSystem2D&>		NIL	Adjusts the region of interest to the position of the inspected object
inMinIntensity	Optional<float>		NIL	Lowest acceptable value for the average pixel value
inMaxIntensity	Optional<float>		NIL	Highest acceptable value for the average pixel value
inMinContrast	float	0.0 -		Lowest acceptable value for the standard deviation of the pixel values
inMaxContrast	Optional<float>	0.0 -	NIL	Highest acceptable value for the standard deviation of the pixel values
outIsPresent	bool&			Flag indicating whether the object is present or not
outIntensity	Optional<float&>		NIL	Average pixel value
outContrast	Optional<float&>		NIL	Standard deviation of the pixel values
outAlignedRoi	Optional<ShapeRegion&>		NIL	Input ROI after transformation (in the image coordinates)

Description

The filter computes basic statistics of the image pixels in selected ROI and checks if they fit the defined ranges. The used statistics are average and standard deviation of the pixel values.

Hints

If the object location is variable, Pass an appropriate local coordinate system to inRoiAlignment.
Define inRoi to specify the image location at which the object presence will be checked.
Investigate the values that appear on outIntensity and outContrast outputs. With this information set inMinIntensity, inMaxIntensity, inMinContrast and inMaxContrast to values which are appropriate for correct objects.
When creating data previews, use outAlignedRoi and NOT inRoi as only the former will be properly aligned to the object location.

Examples