Generating Convex Hulls

Dragonfly lets you generate convex hulls as filled or outlined regions of interest or multi-ROIs, or as meshes. Convex hulls are calculated from the minimum set of points that define a polygon containing all of the labeled voxels of a region of interest or all of the labeled voxels of each connected component in a multi-ROI. If you imagine the points as pegs on a board, you can find the convex hull by surrounding the pegs by a loop of string and then tightening the string until there is no more slack.

In the illustration below, a convex hull as a mesh (in blue) was generated from a region of interest describing the outline of a mechanical part.

Convex hull as a mesh

The options for generating convex hulls include the following:

Convex Hull as a Filled ROI or Multi-ROI… Generates a convex hull as a filled region of interest for the selected ROI, or as a series of convex hulls for each connected component in the selected multi-ROI. You should note that each connected component in the multi-ROI will be filled.

Convex Hull as an Outer Shell ROI or Multi-ROI… Generates a convex hull as an outlined region of interest for the selected ROI, or as a series of convex hulls for each connected component in the selected multi-ROI. You should note that each connected component in the multi-ROI will be outlined.

Convex Hull as a Mesh… Generates a convex hull as a mesh for the selected ROI.