820214.fig.004a
(a)
820214.fig.004b
(b)
820214.fig.004c
(c)
Figure 4: (a) Labeling process using the image gradient magnitude: (left) image gradient magnitude; (center) zooming image area; (right) the numbers are the pixel intensities, red is the stating pixel, green is minimum pixel intensity in the 8-connected neighborhood (in yellow), and the arrow is the searching direction. (b) and (c) are image partitioning in rat lung explants for Figures 1(a) and 1(b).