Sampling and the Fast Fourier Transform

Abstract

Image simulation or image processing with the computer presumes that the image is somehow represented inside the computer. A digital computer naturally operates on numerical data. Therefore an image must be represented as a two dimensional array of numbers inside the computer. Each number is one pixel or spot in the image whose intensity is proportional to its numerical value. The trick is to have a sufficiently large number of pixels so that when they are displayed as an image the individual numbers or pixels are not individually distinguishable. Sampling the image in this manner leads to some specific rules and limitation that are summarized in this chapter.