Figure 9.

Segmentation of homogenous targets: (a) the corpus callosum in a T2 MR image (case 3) and (b) the glioma in a T1c MR image (case 7). The ROIs, which are indicated by the yellow boxes, are shown in the zoomed‐in views for clarity. (a)$-1$ SPs labeled inside (green) and outside (red) of the corpus callosum; (a)$-2$ segmentation by RW; (a)$-3$ segmentation by GC; (a)$-4$ segmentation by SPARSE. The red and green curves in (a)$-2,-3,-4$ represent the calculated and ground truth segmentations, respectively. The yellow arrow in (a)$-2,-3$ indicates the oversegmentation; (b) segmentation of a glioma in a T1c MR image (case 7): (b)$-1$ SPs labeled inside (green) and outside (red) of the brain glioma on only one transversal slice; (b)$-2$ segmentation by RW; (b)$-3$ segmentation by GC; (b)$-4$ segmentation by SPARSE. Upper and lower rows in (b) are the transversal and coronal slices, respectively. The red and green masks in (b)$-2,-3,-4$ represent the calculated and ground truth segmentation; the yellow arrows in (b)$-2,-3$ indicate the oversegmentation.