]>Shells and Spheres: An <i>n</i>-Dimensional Framework for Medial-Based Image Segmentation : Figure 1
980872.fig.001
Figure 1: Each pixel is shown as a number indicating its integer distance from the central pixel. If we denote the central pixel as 𝐱 , then pixels labeled 𝑛 are members of the set 𝐻 𝑛 ( 𝐱 ) . For example, the pixels labeled “3” (shown in bold) comprise the shell 𝐻 3 ( 𝐱 ) .