Figure 2.

Training stage (a) and testing stage (b). (a) The red region is the neighborhood, where all the vertices on the spherical space are used as training samples. (b) The green region is the neighborhood, where all the individual trees are combined together to form a forest in the testing stage. Note that the red and green regions in (a) and (b) could have different sizes. [Color figure can be viewed at http://wileyonlinelibrary.com.]