Module: Thickness Map ()

Description:

Computes the local thickness for each voxel in a binary image, defined as the diameter of the largest ball containing the voxel and entirely inscribed in the object, following the definition of Hildebrand&Ruegsegger, J.Microscopy, 185:1, 1997.

It starts by computing a euclidean distance map inside the object. In a second step, the thickness map T is initialized with the values of the distance map. For each voxel v, with distance map value (v), the ball B centered on v and with radius D is browsed. The thickness T of these neighboring voxels w is set to max(T(w),D(v)). Finally, the thickness map is multiplied by 2 to obtain the largest ball diameter.

Three variants are proposed which consider differently the boundary voxels of the binary object.

Connections:

Data [required]
Input binary image.

Ports:

Boundary Voxels

• "excluded": computes the distance inside the object, starting from the boundary voxels belonging to the object.
• "included": computes the distance inside the object, starting from the boundary voxels just outside the object.
• "averaged": averages the two distance maps.