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CheckPresence_Intensity

Module:	FoundationPro

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

Applications

Quick and easy presence verification, e.g. for missing caps, screws, labels.

Name	Type	Range	Description
inImage	Image		Input image
inRoi	ShapeRegion		Location at which object presence is being checked
inRoiAlignment	CoordinateSystem2D *		Adjusts the region of interest to the position of the inspected object
inMinIntensity	Real *		Lowest acceptable value for the average pixel value
inMaxIntensity	Real *		Highest acceptable value for the average pixel value
inMinContrast	Real	0.0 -	Lowest acceptable value for the standard deviation of the pixel values
inMaxContrast	Real *	0.0 -	Highest acceptable value for the standard deviation of the pixel values
outIsPresent	Bool		Flag indicating whether the object is present or not
outIntensity	Real		Average pixel value
outContrast	Real		Standard deviation of the pixel values
outAlignedRoi	ShapeRegion		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

Connect the inImage input with an appropriate image source. Make sure that this image is available (the program was previously run).
If the object location is variable, Connect 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

Description of usage of this filter can be found in examples and tutorial: Button Presence, Tablets, Parallel Enumeration, Bottle Inspector Part 3: Foam Detection.

CheckPresence_Intensity performed on sample image with inMinIntensity = 80. The foam is present in red rectangle.

Errors

This filter can throw an exception to report error. Read how to deal with errors in Error Handling.

List of possible exceptions:

Error type	Description
DomainError	Region exceeds an input image in CheckPresence_Intensity.

Complexity Level

This filter is available on Basic Complexity Level.

Filter Group

This filter is member of CheckPresence filter group.