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Voids and Inclusions

The Voids and Inclusions tool detects voids and inclusions in 3D grayscale images while ensuring only internal defects are identified. It analyzes the grayscale intensity within the target volume to identify regions that differ significantly from the surrounding material.

Accessing the Tool​

  1. Navigate to the Segmentation tab in the ribbon.
  2. Click Voids and Inclusions in the Create Mask section.

How It Works​

The algorithm analyzes the grayscale intensity within a reference mask to identify regions that:

  • Fall below or above expected intensity thresholds (absolute contrast)
  • Differ significantly from local surrounding intensity (relative contrast)
  • Are completely enclosed within the material (internal defects)

Only internal features are detected—surface-connected regions are excluded.

Parameters​

Target Object(s)​

  • Description: Select the target volume objects on which the operation will be applied
  • Options: Active Volume, Selected Volumes, Visible Volumes, All Volumes

Analysis Type​

Mode​

Choose what to detect:

  • Void: Detect regions with lower intensity than surrounding material (e.g., air pockets, porosity)
  • Inclusion: Detect regions with higher intensity than surrounding material (e.g., dense particles, foreign objects)

Method​

Choose the detection method:

  • Absolute: Use fixed intensity threshold for defect detection
  • Relative: Use percentage difference from local mean intensity

ROI Mask (Optional)​

Checkable group box to restrict analysis to a specific region (unchecked by default):

  • Mask object: Select a mask object to analyze within
  • Effect: When enabled, only analyzes voxels within the specified mask

Analysis Parameters​

Auto Absolute Contrast​

  • Description: Automatically estimate the absolute contrast value
  • Type: Checkbox

Absolute Contrast​

  • Range: 0.0 to 1,000,000.0
  • Default: 3000.0
  • Description: Fixed intensity threshold for defect detection (used in Absolute method)

Relative Contrast (%)​

  • Range: 0.0 to 100.0 %
  • Default: 20.0 %
  • Description: Percentage difference from local mean intensity (used in Relative method)

Auto Air Gray Value​

  • Description: Automatically estimate the air gray value
  • Type: Checkbox

Air Gray Value​

  • Range: -1,000,000.0 to 1,000,000.0
  • Default: 0.0
  • Description: Reference intensity value for air/background

Filter Result (Collapsible)​

Advanced filtering options to refine detected defects:

Probability Threshold​

  • Range: 0.0 to 1.0
  • Default: 0.0
  • Step: 0.01
  • Description: Minimum probability threshold for defect classification

Minimum Size​

Choose units:

  • Volume: 0.0 to 999,999,999.99 mm³ (default: 0.0)
  • Voxels: 1 to 1,073,741,824 voxels (default: 8)

Maximum Size​

Choose units:

  • Volume: 0.0 to 999,999,999.99 mm³ (default: 0.0)
  • Voxels: 1 to 1,073,741,824 voxels (default: 10,000)

Compactness Range​

  • Range: 0.0 to 1.0 for both min and max
  • Default: 0.0 to 1.0
  • Description: Filter by shape compactness measure

Sphericity Range​

  • Range: 0.0 to 1.0 for both min and max
  • Default: 0.0 to 1.0
  • Description: Filter by how spherical the defects are

Volume Fraction Range​

  • Range: 0.0 to 100.0 % for both min and max
  • Default: 0.0 % to 100.0 %
  • Description: Filter by volume fraction of defects

Equivalent Diameter Range​

  • Range: 0.0 to 1,000,000,000.0 mm for both min and max
  • Default: 0.0 to 1,000,000.0 mm
  • Description: Filter by equivalent sphere diameter

Maximum Count​

  • Range: 0 to 1,073,741,824
  • Default: 0 (no limit)
  • Description: Maximum number of defects to detect

Workflow​

  1. Load your volume data and ensure it is active.
  2. Open the Voids and Inclusions tool from the Segmentation tab.
  3. Select the Target object(s) to analyze.
  4. Configure Analysis Type:
    • Choose Mode (Void or Inclusion)
    • Choose Method (Absolute or Relative)
  5. Optional: Enable ROI Mask and select a mask to analyze within a specific region.
  6. Configure Analysis Parameters:
    • For Absolute method: Set Absolute contrast (or enable auto)
    • For Relative method: Set Relative contrast (%)
    • Set Air gray value (or enable auto)
  7. Optional: Expand Filter Result section to refine detection:
    • Set size filters (minimum/maximum in volume or voxels)
    • Set shape filters (compactness, sphericity)
    • Set volume fraction and equivalent diameter ranges
    • Set maximum count to limit number of detected defects
  8. Click Apply to run the detection.
  9. Review the detected defects and adjust parameters if needed.
  10. Click Reset to Default to restore default settings.

Use Cases​

Industrial CT Inspection​

Detect manufacturing defects such as:

  • Air bubbles in cast parts
  • Porosity in additive manufacturing
  • Foreign particle contamination
  • Delamination in composite materials

Medical Imaging​

Identify anatomical features such as:

  • Calcifications within soft tissue
  • Gas pockets in the digestive system
  • Foreign bodies
warning

For industrial quality control applications, validate results against known samples and established inspection standards. Detection sensitivity depends on image resolution, noise levels, and contrast settings.

Tips​

  • Method Selection:
    • Absolute: Best when you know the specific intensity threshold
    • Relative: Best for materials with varying baseline intensity
  • Auto Options: Enable "Auto absolute contrast" and "Auto air gray value" for automatic parameter estimation
  • ROI Mask: Use this to focus analysis on specific regions and exclude irrelevant areas
  • Size Filtering: Set appropriate min/max size to exclude noise while capturing relevant defects
  • Shape Filtering: Use compactness and sphericity ranges to filter by defect shape characteristics
  • Calibration: Test on samples with known defects to optimize detection parameters
  • Reset Button: Use "Reset to Default" to quickly restore all settings to default values

Output​

The tool generates:

  • A mask containing all detected voids and/or inclusions.
  • Optional: Separate masks for each detected defect.
  • Statistical information including count, volume, and size distribution.

See Also​