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CheckPresence_Intensity

Basic

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

See Also

  • ImageAverage – Computes the average of the image pixel values.