
Chapter 1
Introduction
1.1 Images and Pictures
As we mentioned in the Preface, human beings are predominantly visual creatures: we
rely heavily on our vision to make sense of the world around us. We not only look at things
to identify and classify them, but we can scan for differences, and obtain an overall rough
“feeling” for a scene with a quick glance.
Humans have evolved very precise visual skills: we can identify a face in an instant; we
can differentiate colors; we can process a large amount of visual information very quickly.
However, the world is in constant motion: stare at something for long enough and it will
change in some way. Even a large ...