Compression Algorithm Fundamentals

Abstract

As stated in Chapter 1, an image is a representation of an object. Technically speaking, images are two-dimensional signals received by the human visual system. When an image is digitized, it becomes a digital image. The most basic requirement for digital image compression is the digitization of an image object (or simply an image) such as a physical picture, a document page, and the like. The digitization of an image involves two processes, sampling and quantization. The sampling process maps a physical image into an array of pixels by spatially sampling points of the physical image. The quantization process on the other hand, uses a limited number of bits to represent each pixel.