Introduction

A picture may be worth a thousand words, but it requires far more computer memory to store. Images are stored on computers as collections of bits representing pixels, or points forming the picture elements. (A bit is a binary unit of information which can answer one “yes” or “no” question.) Since the human eye can process large amounts of information, many pixels—some 8 million bits’ worth—are required to store even moderate-quality images. These bits provide the “yes” or “no” answers to 8 million questions that determine what the image looks like, though the questions are not the “is it bigger than a bread-box?” variety but a more mundane “what color is this or that pixel?”