Documentation/4.1/Modules/ThresholdScalarVolume

Introduction and Acknowledgements

This work is part of the National Alliance for Medical Image Computing (NA-MIC), funded by the National Institutes of Health through the NIH Roadmap for Medical Research, Grant U54 EB005149. Information on NA-MIC can be obtained from the NA-MIC website. Author: Nicole Aucoin, SPL Contact: Nicole Aucoin, <email>nicole@bwh.harvard.edu</email>

Surgical Planning Laboratory   NA-MIC   NAC

Module Description

Threshold an image.

Set image values to a user-specified outside value if they are below, above, or between simple threshold values.

ThresholdAbove: The values greater than or equal to the threshold value are set to OutsideValue.

ThresholdBelow: The values less than or equal to the threshold value are set to OutsideValue.

ThresholdOutside: The values outside the range Lower-Upper are set to OutsideValue.

Although all image types are supported on input, only signed types are produced.

Use Cases

Most frequently used for these scenarios:

• Use Case 1: threshold a CT to recover bone structures
• Use Case 2: create a mask volume to limit processing to a region of a brain (for example, a tumor showing up as higher intensity)

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  GUI

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  After

Tutorials

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Panels and their use

Parameters: IO Input Volume: Input volume Output Volume: Thresholded input volume Filter Settings Threshold Value: Threshold value Lower: Lower threshold value Upper: Upper threshold value Outside Value: Set the voxels to this value if they fall outside the threshold range Threshold Type: What kind of threshold to perform. If Outside is selected, uses Upper and Lower values. If Below is selected, uses the ThresholdValue, if Above is selected, uses the ThresholdValue.

GUI

Similar Modules

• The Editor module also has a threshold function

References

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