On the Fiber Identification Visualization tab next to the Results tab, several possibilities of visualizing the results are listed.

Identified Fibers

To visualize the fibers identified by the algorithm, click Load *.g32 in the GeoDict Result Viewer under the Fiber Identification Visualization tab.

Set the structure to invisible, to see only the identified fibers, by clicking Yes in the opening dialog.

The identified fibers are shown in a variety of colors.

Load Curved Fiber Fit / Load Straight Fiber Fit

In the same way, the curved fiber fit (and the straight fiber fit if Short Circular Fiber was selected in the Fiber-Shape Analysis panel of the Identify Fibers (AI) options) can be loaded by clicking on their Load *.gad buttons under the Fiber Identification Visualization tab. In the loaded .gad files, fibers are contained as analytical objects, with information about fiber diameter, etc. After the identification of fibers, the analytic information contained in the .gad files can be used for modifications of the structure model or further calculations that require fiber analytic data.

Load Labeled Structure

Clicking the (Load labeled structure) Load *.gdt button under the Fiber Identification Visualization tab, loads the fibers together with the identified centerlines.

Visualize the loaded labeled structure with the centerlines in 2D (View → 2D Cross section in the menu bar).

Looking at the centerlines helps you judge how well the fibers were identified and whether the threshold setting is appropriate.

• If the centerlines are broken or fragmented, try running FiberFind – Identify Fibers (AI) again with a lower threshold.
• If the centerlines look too thick, increasing the threshold may improve the result.

You can explore the influence of the threshold interactively by loading the Confidence Field as described in the following.

Load Confidence Field

Click the (Load Confidence Field) Load *.npz button to load the unsegmented data of the fiber identification. The confidence field is stored channel_1:Numpy Field, so it is recommended to only check and load this component.

Set the structure to invisible, by unchecking the Structure tab in the Visualization panel, above the Visualization area of the GUI.

Show the result only for the fibers, by deselecting the material with ID 0 in the Visibility pull-down menu of the Volume Field tab.

The Threshold parameter defines the limit probability value for the decision whether a voxel is a centerline voxel or not. Select >= as Clip Mode to see the voxels that are identified for separate fibers if this value were to be set as Threshold for the fiber identification (see Fiber identification section).

The goal is to find a threshold which does not result in fragmented centerlines but also does not fuse the centerlines of neighboring fibers. For this example a default threshold value of 0.5 would lead to a strong fragmentation of fibers as many voxels are not identified to be the centerline of a fiber and thus the fiber itself is subdivided into multiple parts. The representation of identified fibers with threshold 0.5 in the Volume Field tab implies that the fibers are too thin (left side of the following figure).

A threshold of 0.2 in turn seem to be a more appropriate value for this example, as seen below.

Taking this observation into account an Identify Fibers (AI) run can be done by setting the threshold to 0.2 and, if an identification result is available already, using the neural network output nnOutput.npz in order to save computation time (see Fiber identification section).

Load Fiber-Oriented Distribution

Select the (Load Fiber-Orientation Distribution) Load *.gof button to load information about the fiber orientation.

Select e.g. Orientation:AngleToZ to get a visualization of the angle with respect to the z-axis for each identified fiber segment.

This option is available only if Save Fiber-Orientation Distribution as .gof was selected on the Output Options tab.

Again, set the structure to invisible by unchecking the Structure tab in the Visualization panel, above the Visualization area of the GUI. Show the result only for the fibers by deselecting the material with ID 0 in the Visibility pull-down menu of the Volume Field tab.

Since in the example shown here, fibers are oriented mainly in x- and y-direction, the angle to the z-axis is high for most of the segments.

Load Fiber Segmented by Property

Load the structure with fibers of different type assigned to different material IDs in *.gdt format or with analytic data in *.gad format, by clicking Load *.gdt for Load Fibers Segmented by Property and Load *.gad for Load Fibers Segmented by Property (analytic fibers), respectively.

Fibers with different material IDs, according to the number of different fiber types selected under the Results tab, are shown in the Visualization Area.

Additionally, GAD objects can be loaded and visualized for the fibers segmented by property with the last available button Load Fibers Segmented by Property (analytical fibers).