ABSTRACT
In the Two preceding chapters, we examined some basic aspects of the visual system. In Chapter 3, we studied the mechanisms that transduce light energy into the energy required by our neural processing apparatus. In Chapter 4, we outlined some of the prerequisites for vision, with an emphasis on the importance of edges and change. Although you may not be consciously aware of edges, you certainly can notice them when we call your attention to them. For instance, as you look at this textbook, you can readily perceive the letters on the page as patterns of edges. Your book’s cover forms edges against a background that is itself filled with edge information. Edges abound, yet you do not see edges—you see objects! You see letters, books, faces, tables, chairs, and walls. Of course, most of these objects are three-dimensional. To simplify our discussion of shape perception, we’ll defer most of the discussion of how we perceive the depth of such objects until the next chapter.
