We propose a new scanning method for image signals using a tree structure of automata. The tree is scanned selectively along the signal path for realizing both lower power consumption and a kind of image compression by skipping nonactive elements. We designed the node automata along with photo-detectors of 3232 in a 7.2 mm7.2 mm chip using a 1.5µm CMOS technology. We demonstrate applications of the tree structure using its feature of selective activation; a moving picture compression using inter-frame difference, an adaptive resolution scan like human eyesight and a motion compensation as examples.