ISODATA visualization — three snapshots.

• (1) Five arbitrary initial cluster means plotted in 2-D spectral space.
• (2) After the first pass — cluster means have shifted toward the actual pixel densities.
• (3) Second pass — means have stabilized closer to true cluster centers.

Source: ERDAS Field Guide, Figures 6-3/6-4/6-5, pp. 215–216.