1 - Motivation

Summary

The importance of compression

It is easy to recognize the importance of data compression technology by observing the way it already pervades our daily lives. For instance, we currently have more than a billion users [1] of digital cameras that employ JPEG image compression, and a comparable number of users of portable audio players that use compression formats such as MP3, AAC, and WMA. Users of video cameras, DVD players, digital cable or satellite TV, hear about MPEG-2, MPEG-4, and H.264/AVC. In each case, the acronym is used to identify the type of compression. While many people do not know what exactly compression means or how it works, they have to learn some basic facts about it in order to properly use their devices, or to make purchase decisions.

Compression's usefulness is not limited to multimedia. An increasingly important fraction of the world's economy is in the transmission, storage, and processing of all types of digital information. As Negroponte [2] succinctly put it, economic value is indeed moving “from atoms to bits.” While it is true that many constraints from the physical world do not affect this “digital economy,” we cannot forget that, due to the huge volumes of data, there has to be a large physical infrastructure for data transmission, processing, and storage. Thus, just as in the traditional economy it is very important to consider the efficiency of transportation, space, and material usage, the efficiency in the representation of digital information also has great economic importance.