Intercepts

3D Measurements > Intercepts

Random Lines

Measures metrics such as mean intercept by drawing a specified number of random lines through the features in the reconstruction.

1. Number of Lines

Number of lines to draw

2. Noise Removal

Method for removing small intercepts

• Reject < / =: Simply ignores intercepts below a certain length
• Fit to Noise: (Only for “Random Lines”) Fits an exponential to the first few bins and subtracts this exponential out the intercept histogram.

3. Noise Thresholds

Thresholds for either the minimum intercept length (for “Reject </=”), the number of bins to use for “Fit to Noise”

4. Partial Intercepts

Choose whether to discard or keep intercepts that start or end at an image edge

5. Save All Intercepts

Choose whether to save all intercept lengths into text files

6. Lines Along Vector

Choose whether to draw all “Random Lines” along a specific direction. Starting points of each line will still be random.

Measurements

• Mean Intercept – Objects: Average length of intercepts which pass through selected features (objects)
• Mean Intercept – Holes: Average length of intercepts which pass through un-selected areas (holes)
• Mean Inverse Intercept – Objects: Average inverse length of intercepts which pass through selected features (objects)
• Mean Inverse Intercept – Holes: Average inverse length of intercepts which pass through un-selected areas (holes)
• Mode Intercept – Objects: Mode (most common) length of intercepts which pass through selected features (objects)
• Mode Intercept – Holes: Mode (most common) length of intercepts which pass through un-selected areas (holes)
• Mode Inverse Intercept – Objects: Mode (most common) inverse length of intercepts which pass through selected features (objects)
• Mode Inverse Intercept – Holes: Mode (most common) inverse length of intercepts which pass through un-selected areas (holes)
• Total Line Length: Total length of all lines which are drawn in order to collect intercepts.
• Total Intersections: Number of intersections produced between the drawn lines and intercepted features.

References

[1] ASTM E112-13, Standard Test Methods for Determining Average Grain Size, ASTM International, West Conshohocken, PA, 2013, www.astm.org