Slice-n-Swipe: A free-hand gesture user interface for 3D point cloud annotation.

Three-dimensional point clouds are generated by devices such as laser scanners and depth cameras, but their output is a set of unstructured, unlabeled points. Many scenarios require users to identify parts of the point cloud through manual annotation. Inspired by the current generation of "natural user interface" technologies, we present Slice-n-Swipe, a technique for 3D point cloud annotation based on free-hand gesture input. The technique is based on a chef's knife metaphor, and uses progressive refinement to allow the user to specify the points of interest. We demonstrate the Slice-n-Swipe concept with a prototype using the Leap Motion Controller for free-hand gesture input and a 3D mouse for virtual camera control.