ABSTRACT
The growth in global use of the Internet, coupled with improvements in methods of transmitting digital data, such as the widespread adoption of broadband and wireless networking, mean that an ever greater range of information is represented using digital imagery. Improvements in digital image sensor technology enable the production of larger digital images at acquisition. In many cases the unique attributes of images, for example their spatial and statistical structures and the typical characteristics of natural images in the frequency domain are exploited to reduce file size. In a digital image, the information is contained in the arrangement of pixel values, but the data are the set of binary digits that represent it when it is transmitted or stored. In images where there are repeating patterns, there may be correlation between groups of pixels. The process of coding in the context of image compression involves assigning a set of binary digits to source symbols.
