A few years ago, images and video were represented using ``de facto'' file formats, typically developed by a single organization, with specifications released to the public. Nowadays, international standardization organizations cooperate to come up with international standards for the same purposes, building their decisions on years of research. A couple of standards, such as JPEG for still images and MPEG for video, are fully defined, while others are being worked upon.
This chapter will give an introduction to image and video representation, starting with the sampling process. Compression plays an important role in modern schemes for video representation, so the next two sections focus on image compression, including describing the compression method used in JPEG. After discussing single image compression, the following sections are dedicated to video compression, and how one may exploit similarities in nearby frames of a video sequence. This section includes brief descriptions of the standards H.261 and MPEG.
The reader may want a basic knowledge of data compression before reading this chapter. Consult appendix A or any of it's referenced papers for an introduction.